book of abstracts - brightlands rolduc polymer conference · 5 abstract id 35 title designing a...

BrightlandsRolduc PolymerConference

Innovative Polymer Materials for Future Health

September 9-11, 2019

Book of Abstracts

Content list BIOBASED AND BIODEGRADABLE POLYMERS FOR MEDICAL APPLICATIONS ......................................... 3

POLYMERS FOR DRUG DELIVERY AND DIAGNOSTICS AND TREATMENT .............................................. 28

POLYMERS FOR PERSONAL CARE, MEDICAL DEVICES, HYGIENE AND MEDICAL PACKAGING .............. 51

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BIOBASED AND BIODEGRADABLE POLYMERS FOR MEDICAL APPLICATIONS Abstract ID 115 Title α-amino acid based polyester copolymers for biomedical applications Author(s) Mr Vahid Ansari1 2

P / Mr Andrea Calore1 2 / Prof Lorenzo Moroni1 / Dr Jules A.W. Harings3 / Dr Katrien V. Bernaerts3 C C: Corresponding author P: Presenting author Affiliation(s) 1 Complex Tissue Regeneration Department, MERLN Institute for Technology Inspired Regenerative Medicine, Maastricht University 2 Brightlands Materials Center 3 Aachen-Maastricht Institute for Biobased Materials (AMIBM), Maastricht University Content A special class of polyester copolymers including α-amino acids in the backbone was synthesized for biomedical applications. Introducing α-amino acids in the structure can decrease the effective acidity of the degradation products in comparison to the hydroxy acids of degraded polyesters such as PLA. The thermal stability and mechanical properties of the synthesized polyester copolymers were studied in comparison with a commercial biomedical grade copolymer of L-lactide and glycolide in an 82/18 molar ratio (PLG8218). The synthesized copolymers exhibited proper thermal stability with glass transition temperatures much lower than that of PLG (56 °C). These Tg values, reasonably below the body temperature, provide access to appealing mechanical properties and biodegradation of these polymers in vivo. Furthermore, with their suitable mechanical properties, coupled with higher ductility and thermal stability than PLG, they can be introduced as favorable polymers for biomedical applications in the future. Presentation mode Oral presentation & poster presentation

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Abstract ID 110 Title Controlling Blood Coagulation in Supramolecular Vascular Access Grafts via Feedback-Response Mechanisms Author(s) Ir. Boris Arts1 C P / Prof. Dr. Patricia Dankers1 C: Corresponding author P: Presenting author Affiliation(s) 1 University of Technology Eindhoven Content Currently 1 in 1000 patients in the US suffer from end-stage renal disease and require hemodialysis. Hemodialysis is a medical procedure to remove waste products from the blood where the blood circulation of the patient is directly connected to a dialysis machine via an arteriovenous fistula (AVF) or vascular access graft (VAG). Due to the high failure rate of AVFs the alternative, VAGs, have been widely applied. However the primary failure of VAGs are due to its low patency rates (the time the graft remains open), which is primarily caused by thrombosis. Several studies showed that coating the inner lining of the graft, e.g. with heparin, improves the patency rate by the inhibition of blood clot formation and reduction of platelet adhesion. However major concerns are expressed regarding the long-term efficacy of those coatings, mainly because the coating may become unstable, or become ineffective due to the formation of a physical barrier by blood proteins. Therefore the aim of this study is to introduce a feedback-response system on the surface of these grafts to control the blood coagulation pathway and thereby improve the use of those vascular grafts for haemodialysis. Heparin is conjugated to the surface of our supramolecular polymer-based VAGs via a thrombin cleavable peptide. When in contact with whole blood the enzyme thrombin is designed to cleave the peptide causing heparin to be released (response). In turn heparin can form an inhibitory complex with anti-thrombin, naturally present in blood, thereby inhibiting thrombin activity and decreasing heparin release (feedback). To this extent a thrombin cleavable and non-cleavable peptide were synthesized. Their activity was assessed in solution and at the surface of supramolecular polymer films. It was shown that the Michaelis-Menten constant was a factor 1000 lower compared to the in vivo sequences in fibrinogen. Also when substituting the glycine amino acid residue at the cleavage site to an aspartic acid the peptide was not susceptible to thrombin. When thrombin cleavable peptides were incorporated in supramolecular polymer films the peptide could still be cleaved. However no significant difference was observed in cleaving efficiency between different amounts of additive in the film. It is postulated that this is an effect of additive presentation at the surface. Atomic force microscopy and water contact angle measurements indicate that the additive is present at the surface. Presentation mode Oral presentation

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Abstract ID 35 Title Designing a biobased, elastin inspired polymer-peptide hybrid for tissue-engineering applications Author(s) Anna M. J. Coenen1 P C / Katrien V. Bernaerts1 / Jules A. W. Harings1 / Samaneh Ghazanfari1 / Stefan Jockenhoevel1 2 C: Corresponding author P: Presenting author Affiliation(s) 1 Maastricht University, Aachen-Maastricht Institute for Biobased Materials (AMIBM), Brightlands Chemelot Campus 2 RWTH Aachen University, AME-Helmholtz Institute for Biomedical Engineering, Department of Biohybrid & Medical Textiles (BioTex) Content Tissue-engineering is a fast growing research area that aims to overcome the organ shortage and post-transplantation complications, such as organ rejection and calcification. Furthermore, engineered tissues have the ability to grow and remodel in vivo, reducing the need for multiple surgeries. Tissue-engineered heart valves (TEHVs), for example, are a promising alternative course of treatment compared to current treatment options, such as mechanical or bovine heart valves. However, TEHVs have to meet both mechanical and biological requirements of a native heart valve to lead to a successful implantation. Within the native heart valve collagen and elastin physio-mechanically cooperate to allow for the opening and closing of the heart valve. In general, collagen provides the strength whereas elastin provides the necessary flexibility. Unfortunately, current TEHVs exhibit higher stiffness compared to their native counterparts due to limited elastin produced by the cells in vivo. To introduce the elasticity into the TEHVs an elastic polymer-peptide hybrid (EPPH) inspired by the native elastin structure is physio-chemically designed. Native elastin consists of alternating hydrophobic and hydrophilic blocks causing the high elasticity of the molecule. In the EPPH, the hydrophobic blocks are maintained by using elastin-like polypeptides (ELPs) but coupled to polydioxolane (PDXL), a potential biobased polymer. For the coupling of the ELP to PDXL, it is important that bifunctional-PDXL is synthesized. However, the cationic ring-opening polymerization of dioxolane is prone to cyclization. To obtain the linear polymer, different reaction conditions were screened and analyzed with a combination of MALDI-ToF and GPC to study their influence on the cyclization. Additionally, the influence of purification of the reaction was studied. Finally, the combination of the synthetic PDXL with the ELPs will result in a highly tunable and biocompatible material for heart valve tissue-engineering.

Presentation mode Oral presentation & poster presentation

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Abstract ID 180 Title LCA of the Solvent-free Shvo-catalyzed Hydrogenation of Levulinic Acid to Gamma-valerolactone Author(s) Christian van Slagmaat1

P C , Marie Delgove 1 , Yvonne van der Meer 1 C: Corresponding author P: Presenting author Affiliation(s) 1 Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University Content Levulinic acid (LA) was recognized as a ‘Top value added chemical from biomass by the US DOE Office of Energy Efficiency and Renewable Energy in 2004, and received a tremendous amount of attention in modern chemical research. Among the numerous transformations of LA, we highlight its hydrogenation to γ-valerolactone (GVL) as a key pathway towards biobased adipic acid - our desired final product. Although the hydrogenation of LA can be established with a wide variety of catalysts according to literature, certain difficulties are still to be overcome. For example, catalyst poisoning by typical bio-derived impurities and over-reduction are well known issues. In order to provide an alternative catalyst for biobased GVL production that could fulfill the requirements for efficient catalytic performance, a robust homogeneous ruthenium type was selected: the Shvo catalyst. In this work, the solvent-free H2-mediated hydrogenation of LA to GVL was established using various precursors of the well-known Shvo catalyst. Kinetic studies of the optimized reaction were compared to earlier reported examples of this conversion using formic acid (FA) [1] and isopropanol (IPA) [2] as hydrogen donor. Key to this comparison is the fact that the use of H2 does not yield additional byproducts, while the use of FA and IPA produce stoichiometric amounts of CO2 and acetone, respectively. Hence, our new catalytic concept was subjected to a prospective life cycle assessment (LCA), in order to verify its contribution towards a practice of environmentally benign chemistry. This LCA was conducted on laboratory scale in a gate-to-gate¬ setting for the hydrogenation reactions, while the catalyst synthesis was modelled as cradle-to-gate (Scheme 1). From the investigations of various aspects to this hydrogenation reaction, the environmental impacts for the electric energy consumption and for the catalyst synthesis were determined to be the major contributors. Ultimately, the solvent-free H2-mediated LA hydrogenation established in this work was evidenced to be the environmentally friendliest concept. Scheme 1: The studied boundaries for the production of GVL from LA on laboratory scale: Comparative gate-to-gate assessment including [1] the syntheses of the Shvo catalyst precursors, [2] the transfer hydrogenation of the substrate using FA as reductant, [3] the transfer hydrogenation of the substrate using IPA as reductant, [4] the hydrogenation of the substrate using H2. All syntheses and chemical transformations take downstream processing and electrical energy consumption into account.


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Abstract ID 29 Title Biohybrid small caliber vascular grafts with tunable compliance and off-the shelf availability Author(s) Dr. Alicia Fernández Colino1 P C / Frederic Wolf1 / Prof. Thomas Schmitz-Rode2 / Prof. José Carlos Rodríguez-Cabello3 / Prof. Stefan Jockenhoevel1 4 / Dr. Petra Mela1 C: Corresponding author P: Presenting author Affiliation(s) 1 Dept. of Biohybrid & Medical Textiles (Biotex), AME –Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University 2 Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University 3 Bioforge Lab, University of Valladolid, CIBER-BBN, Valladolid 4 AMIBM-Aachen-Maastricht-Institute for Biobased Materials, Maastricht University Content Introduction Vascular disease is a leading cause of death worldwide1, but small diameter vascular bypass grafting is restricted by the limited availability of autologous vessels, and the suboptimal performance of prosthetic grafts. In this work, we aim at developing biohybrid vascular implants that combine the off-the-shelf availability, normally provided by synthetic grafts, with the hemocompatibility and remodeling capability of native vessels. Materials and Methods The vascular grafts were fabricated by combining clickable elastin-like recombinamers (ELRs)2,3 with technical textile components (warp knitted polyvinylidene fluoride (PVDF) and electrospun polycaprolactone (PCL) meshes). The fabrication materials were processed by injection-molding and salt-leaching/gas foaming techniques. SEM was used to investigate the microstructure. The hemocompatibility of the grafts was investigated by platelet adhesion. The mechanical characterization included burst strength, suture retention and compliance tests. Cellular studies were carried out with smooth muscle cells and endothelial progenitor cells, and subsequently analyzed by immunohistochemistry. Results and Discussion The developed vascular grafts featured elastic properties and hemocompatibility provided by the ELRs, besides suturability, long term stability, burst strength and tunable compliance provided by the technical textile components. Different from the clinically available prosthesis, the biohybrid vascular grafts were able to match the compliance of the native vessels in the low, normal and higher pressure ranges. Cellular studies showed cell infiltration, ECM production, and endothelialization, which make these grafts of high interest for in situ tissue engineering. Conclusions Overall, our biohybrid fabrication strategy has resulted in promising off-the-shelf hemocompatible vascular grafts for endogenous tissue regeneration by addressing the known limitations of current vessel substitutes. [1] Townsend, N., et al. Eur Heart J. 37, 3232 (2016) [2] Gonzalez de Torre, I., et al. Acta Biomaterialia. 10, 2495 (2014) [3] Fernández-Colino A., et al. Materials Science and Engineering: C. 88, 140 (2018) Presentation mode Oral presentation

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Abstract ID 111 Title Biodegradable polymers blends base on polylactic acid (PLA), polyhydroxybutyrate (PHB) and thermoplastic starch (TPS) Author(s) Ms Ivana Galisova1 P C / Mr Patrik Jurkovic1 / Mr Roderik Plavec1 / Mr Jozef Feranc1 / Ms Ida Vaskova1 / Mrs Zuzana Vanovcanova1 / Ms Katarina Tomanova1 / Mrs Leona Omanikova1 / Ms Elena Medlecka1 / Ms Lucia Danisova1 / Mr Jan Bockaj1 / Prof Pavol Alexy1 / Ms Martina Repiska1 C: Corresponding author P: Presenting author Affiliation(s) 1 Faculty of Chemical and Food Technology Slovak University of Technology in Bratislava Content The current pressure of society and legislation leads to use of higher among of new type biomaterials, mainly as a replacement for commercial plastics. Plastics are called biomaterials if they are either from renewable sources or biodegradable. But only polymers, which fulfill both these parameters are considered to be really environmental. PLA, polyhydroxyalkanoates and TPS belong to this class of materials. Unfortunately each of them has application or processing disadvantages. We can prepare materials with good processing properties and better toughness by combination of these polymers and additives with appropriate concentration ratio. But also special preparing methods of these blends are necessary to prepare materials with the best properties. We deal with two generations of these blends: •1st generation contains two polymers (PLA, PHB) and different additives [1] •2nd generation contains three polymers (PLA, PHB, TPS) and different additives [2] We have achieved considerable increase of elongation at break by combination of these polymers in comparison with the initial polymers. We have also significantly improved the heat deflection temperature. It becomes surprising that the combination of brittle initial polymers leads to the preparation of flexible and tough material. Our blends have not only good physico-mechanical properties but also they are still biodegradable in different conditions. 1st generation is able to degrade in industry compost while 2nd generation is even degradable in home compost, soil and water. Properties of the final products can be adjusted to their purpose by the qualitative and quantitative composition of polymeric blends. It is therefore possible to prepare plastics suitable for foil in packaging industry, injection molding, additive manufacturing and, due to their biocompatibility, also plastics suitable for medical applications. [1] Alexy, P. et al. PCT/SK2012/000004 Biologically degradable polymeric composition with high deformability [2] Alexy, P. et al. PCT/SK2017/050009 Biodegradable polymer blend and method for its preparation Presentation mode Poster presentation

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Abstract ID 136 Title New kids in lactone polymerization: highly active and robust iron and zinc guanidine complexes as superior catalysts Author(s) Prof. Dr. Sonja Herres-Pawlis1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 RWTH Aachen University Content Polylactide (PLA) has conquered the bioplastics market since it is fully CO2 neutral, biodegradable and biocompatible. The monomer of PLA, lactide (LA), is synthesized via a biotechnological route from starch biomass and degrades depending on chain length and crystallinity in few months. Lactone polymerization is most efficiently done in a ring-opening polymerization (ROP) via the coordination-insertion mechanism. It excels other polymerization mechanisms with fast polymerization rates, high control on the polymerization and producing high molar mass polymers. The industrially used catalyst for the polymerization of LA is tin(II)octanoate (Sn(Oct)2) with alcohol as co-initiator, however, while the polymer degrades, tin residues will accumulate in the environment (e.g. via industrial composters). Sn(Oct)2 is used as catalyst for PLA even as food packaging material, nevertheless the toxicity of tin is known. A huge variety of catalysts are already known for the ROP of LA, but to date none could stand the high criteria of industrial application to substitute the tin compound. An alternative to Sn(Oct)2 should only contain biocompatible metals and be highly active in industrial conditions: it has to polymerize under solvent-free conditions with small catalyst loadings and must be robust towards air, moisture and small amounts of impurities in technical grade LA. Due to their good biocompatibility, high Lewis acidity and low cost, zinc and iron are prominent metal candidates for sustainable catalysts. Zinc catalysts have been thoroughly investigated. In comparison, iron catalysts have been given less attention. A number of iron(II) halide salts and carboxylic acid derivatives were investigated, but no superior polymerization activity could be observed. However, due to their sensitivity, the polymerization conditions needed exclude them from industrial relevance. We recently showed for the first time that iron(II) can be active in the polymerization of LA with a neutral bis(pyrazolyl)-bipyridinylmethane ligand system. We herein present the first robust complexes with a biocompatible metal being more active in the polymerization of LA than Sn(Oct)2. To go ahead on the way towards a sustainable catalyst for the industrial polymerization of lactide, more iron(II) and zinc hybrid guanidine complexes are investigated concerning their molecular structure and applied to the ring-opening polymerization of lactide. The complexes can polymerize unpurified technical grade rac-lactide as well as recrystallized ʟ-lactide in bulk with monomer to initiator ratios of more than 5000:1 in a controlled manner via the coordination-insertion mechanism to long chain polylactide. Moreover, the ROP of caprolactone and copolymers with lactide will be reported. For some complexes, even polymerization under “immortal” conditions has been observed. [1] P. M. Schäfer, M. Fuchs, A. Ohligschläger, R. Rittinghaus, P. McKeown, E. Akin, M. Schmidt, A. Hoffmann, M. A. Liauw, M. D. Jones, S. Herres-Pawlis, ChemSusChem 2017, 10, 3547 [2] P. M. Schäfer, P. McKeown, M. Fuchs, R. D. Rittinghaus, A. Hermann, J. Henkel, S. Seidel, C. Roitzheim, A. N. Ksiazkiewicz, A. Hoffmann, A. Pich, M. D. Jones, S. Herres-Pawlis, Dalton Trans. 2019, DOI: 10.1039/C8DT04938F [3] R. D. Rittinghaus, P. M. Schäfer, P. Albrecht, C. Conrads, A. Hoffmann, A. Ksiazkiewicz, O. Bienemann, A. Pich, S. Herres-Pawlis, ChemSusChem 2019, doi.org/10.1002/ cssc.201900481

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Abstract ID 87 Title Spider silk from plants: a biobased green polymer Author(s) Dr. Julia Jansing1 C P / Prof. Dr. Udo Conrad2 / Asst. Prof. Dr. Luisa Bortesi1 C: Corresponding author P: Presenting author Affiliation(s) 1 Maastricht University, Aachen-Maastricht Institute for Biobased Materials, Molecular and Applied Biotechnology 2 Institute of Plant Genetics and Crop Plant Research – IPK, Gatersleben, Germany Content Spider silks are remarkable natural polymers and their tensile strength and extensibility make them interesting for both medical and technical applications. Because spiders are territorial it is not possible to farm them for the production of large quantities of silk fibers. For any commercial application, it is therefore necessary to produce the spider silk proteins recombinantly in another organism. Spider silk proteins are large molecules with a highly repetitive structure, and are challenging to produce for most host cells. Dragline silk is of particular interest because it is the strongest known natural material. However, so far it has not been possible to produce native-like silk fibers in satisfactory amounts in any of the tested expression systems. We believe that plants are the best suited platform for the inexpensive large-scale manufacturing of silk fibers. They are cheap to grow, can produce large quantities of recombinant protein, and are amenable to metabolic engineering. Due to the repetitive nature of the spider silk protein fibers, a few amino acids are used disproportionally. The dragline silk for example consists of 40% glycine and 20% alanine. This can lead to a depletion of these amino acids and their tRNAs in the host cell, which in turn limits the production of the silk protein. We developed a metabolic engineering approach aimed at increasing the production of glycine and alanine and their tRNAs. With this approach, we want to optimize the production conditions for the repetitive spider silk proteins in planta and increase the yields. Presentation mode Poster presentation

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Abstract ID 47 Title Biodegradable pcl/gel nanofibers for tissue engineering: effect of halloysite on physical and biological properties Author(s) Prof. Viera Khunova1 C P / Ing. Veronika Pavlinakova2 3 / Ing. David Pavlinak4 / Ing. Zdenka Fohlerová2 C: Corresponding author P: Presenting author Affiliation(s) 1 Faculty of Chemical and Food Technology, Slovak University of Technology 2 Central European Institute of Technology, Brno University of Technology 3 Institute of Materials Chemistry, Brno University of Technology 4 CEPLANT, Masaryk University, Brno Content Halloysite nanotubes (HNTs), two-layered aluminosilicate clay, have a lot of advantages in comparison with both, natural and synthetic nanofillers. For polymer nanocomposites the most important is that HNTs act as reinforcing natural nanofillers. Further benefit is that HNTs can be used as a low-cost nanocontainers for encapsulation and subsequently control release diverse chemically and biologically active substances, capture of tumor cells, adsorption of pollutants, pigments, stabilisers, catalyst carrier and many others (1). In this work we studied the effect of three types of HNTs with different geometry and surface area on structure, morphology, mechanical properties and biocompatibility of polymer nanofibers based on blend of polycaprolactone (PCL) and gelatin (Gel). Elastic biodegradable PCL/Gel nanofibers containing halloysite nanotubes have been prepared by electrospinning process respecting principles of “green chemistry”. Unlike HNTs based polymer nanocomposites, in PCL/Gel/HNTs nanofibers significant reinforcing effect of HNTs has been confirmed up to 6 wt%. In nanofibers containing just 0.5 wt% of HNTs even multiply improvement of mechanical properties has been achieved. Based on the interaction with mouse fibroblasts NIH-3T3 cells all studied PCL/Gel/HNTs nanofibers have been confirmed as non-cytotoxic, moreover there was not observed any effect of HNTs types on their biocompatibility. To summarise, studied PCL/Gel/HNTs nanofibers have a great potential for application in tissue engineering as they are high strenght, biodegradable, biocompatible and non-toxic. Acknowledgment This research was supported by Ministry of Education of the Slovak Republic, Grant VEGA 1/0486/19 and by Ministry of Education Youth and Sports of Czech Republic, LO1411 (NPU I). [1] R.F. Fakhrullin, Y.M. Lvov, Halloysite clay nanotubes for tissue engineering, Nanomedicine 2016, (1117), 2243-2246 Presentation mode Oral presentation

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Abstract ID 124 Title Understanding blends of thermotropic LCP’s Author(s) Ir Gijs de Kort1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 AMIBM Content Blends of thermoplastic polymers and main chain thermotropic LCP’s have been a topic of study for over 40 years. The anisotropic nature of these LCP’s allows for effective reinforcement in blends[1], given that the blend has a suitable morphology[2]. A great benefit of thermotropic LCP’s over other means of reinforcement is that they are processable in the melt, which means that composites are producible via conventional processing techniques (eg. extrusion and injection molding) and that the resulting composites are potentially recyclable. High melting temperatures of commercially available thermotropic LCP’s, and failure to obtain the right morphology are factors limiting the actual application of these types of composites. In this study, blends containing two different thermotropic LCP’s were evaluated. We compared a commercially available, fully aromatic LCP and a bio-based, aromatic-aliphatic LCP[3,4] (in-house). Both these LCP’s allow processing at relatively low temperatures (Tprocessing< 240°C). The flow- and thermal behavior of the LCP’s and matrix were analyzed via rheology. The morphology of the composite after different processing steps was assessed via a combination of microscopy (POM), electron microscopy (SEM), and wide-angle X-ray diffraction (WAXD). The mechanical behavior of the different composites was evaluated via tensile testing. From the thermal behavior and flow behavior of the LCP’s and the matrix, we were able to understand the development the morphology of the blends during the processing and understand relevant differences in the morphology and mechanical properties of the final object. Additionally, the recyclability of this type of composite was investigated. The insights gained in this study have allowed us to better understand composites containing thermotropic LCP’s and provided valuable information to evaluate the success of a combination of filler and matrix beforehand. [1] DeMeuse, M. T. & Kiss, G. Liquid crystal polymers (LCPs) as a reinforcement in high temperature polymer blends. High Temperature Polymer Blends (Woodhead Publishing Limited, 2014). [2] Lee, M. W. et al. Novel approach to fibrillation of LCP in an LCP/PP blend. J. Appl. Polym. Sci. 86, 2070–2078 (2002). [3] Wilsens, C. H. R. M. et al. Processing and performance of aromatic-aliphatic thermotropic polyesters based on vanillic acid. Polym. (United Kingdom) 60, 198–206 (2015). [4] de Kort, G. W. et al. Effect of shear rate on the orientation and relaxation of a vanillic acid based liquid crystalline polymer. Polymers (Basel). 10, 6–9 (2018).

Presentation mode Oral presentation

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Abstract ID 150 Title Tandem Synthesis of Biodegradable Camphoric-based Polyesters and their Chemical Functionalizations Author(s) Dr Zahra Mazloomi1 P C / Ass. Prof. Carine Robert1 / Prof. Christophe Thomas1 C: Corresponding author P: Presenting author Affiliation(s) 1 Chimie ParisTech PSL University, CNRS, Institut de Recherche de Chimie Paris Content Aliphatic polyesters outperform other promising biodegradable polymers due to their wide range of applications from packaging to more advanced biomedical devices.1 Several efficient catalysts have been reported for synthesis of the polyesters by using cyclic anhydrides and epoxides via ring-opening polymerization (ROP) reactions.2 Our group initiated a research effort to synthesis aliphatic polyesters by tandem catalytic transformation using commercially available salen complexes, while monomers (that is, cyclic anhydrides) are synthesized from dicarboxylic acids and subsequently copolymerized with epoxides via ring opening polymerization process (Scheme 1).3 In order to further extend the applications of thermoplastics, it is necessary to tune their physico-chemical properties. In particular the introduction of functional groups is highly desirable to impart hydrophilicity and to allow post-polymerization derivatization.4 In this communication I will present our progress in the synthesis of new biosourced polyesters containing olefinic moiety and their post-functionalization via cross metathesis, epoxidation and dihydroxylation. Besides, their thermal properties will be represented that measured by DSC analysis. [1] E. Villemin, Y. C. Ong, C. M. Thomas, G. Gasser, Nat. Rev. Chem. 2019, 3, 261-282. [2] M. J.-L. Tschan, E. Brulé, P. Haquette and C. M. Thomas, Polym. Chem., 2012, 3, 836-851. [3] C. Robert, F. de Montigny and C. M. Thomas, Nature Commun., 2011, 2, 586, doi: 10.1038 / ncomms1596. [4] L. Fournier, C. Robert, S. Pourchet, A. Gonzalez, L. Williams, J. Prunetc, C. M. Thomas, Polym. Chem., 2016, 7, 3700-3704.


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Abstract ID 5 Title Towards the first high-performance, semi-crystalline polyesters based on bis-pyrrolidones obtained from renewable itaconic acid Author(s) Geert Noordzij1 2

C P / Mrs Manta Roy1 / Ass. Prof Karel Wilsens1 / Prof Sanjay Rastogi1 C: Corresponding author P: Presenting author Affiliation(s) 1 Aachen-Maastricht Institute for Biobased Materials, Maastricht University 2 Chemelot InSciTe Content Itaconic acid, a cheap and renewable building block, can readily be transformed in mono- and bis-pyrrolidone-carboxylic acid monomers by reaction with a mono- or diamine monomer. Through an Aza-Michael addition reaction, these amine groups react with the double bond of itaconic acid, after subsequent ring-closing a pyrrolidone group with a carboxylic acid functionality is generated. Following this route, a wide range of mono- and bis-pyrrolidone-carboxylic acid monomers can be generated by using different (di-)amine functionalized monomers. The obtained monomers can readily be polymerized into various polyesters and polyamides, as has been shown by several research groups in the past. Unfortunately, until date, all bis-pyrrolidone dicarboxylic acid based polymers reported in literature are amorphous in nature. In those polymers, the absence of semi-crystallinity results in a significant amount of water absorption, which plasticizes and softens the materials.1 Therefore, semi-crystallinity is essential to minimize water absorption, and to ensure high performance of these materials. In this work, for the first time, we report on semi-crystalline polyesters based on pyrrolidone carboxylic acid monomers synthesized from itaconic acid. Through careful selection of the used diamines in the synthesis of bis-pyrrolidone-carboxylic acids, and by subsequent polymerization with various diols, polymers with melting temperatures between 150 °C and 220 °C are obtained. Furthermore, the biomass content in these materials is 75% or higher. We have optimized the monomer synthesis procedure, and identified several side-products. Using standard polycondensation conditions high molecular weight material (25 kg/mol (Mn), 55 kg/mol (Mw)) was readily obtained. Lastly, the crystallization behavior and thermo-mechanical performance of these materials is described. And thus paving the way for new, high-performance polyesters with a high biomass content.


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Abstract ID 155

Title Cytotoxicity and Antibacterial Activity of Silk Fibroin Based Wound Dressing Films Incorporated with Ginger Extract Author(s) Zehra Özbaş4 C P / Ayça Bal Öztürk1 2 / Zeynep Püren Akgüner2 / Seda Özgen3 / Bengi Özkahraman5 / Fatma Elif Çepni Yüzbaşıoğlu6 / Özgür Çakır6 C: Corresponding author P: Presenting author Affiliation(s) 1 Istinye University, Faculty of Pharmacy, Department of Analytical Chemistry 2 Istinye University, Institute of Health Sciences, Department of Stem Cell and Tissue Engineering 3 Cankırı Karatekin University, Faculty of Engineering, Department of Food Engineering 4 Cankırı Karatekin University, Faculty of Engineering, Department of Chemical Engineering 5 Hitit University, Faculty of Engineering, Department of Polymer Engineering 6 Istanbul University, Faculty of Science, Department of Molecular Biology and Genetics Content In the present study, a new antibacterial polymeric wound dressing film was developed for faster and effective treatment of skin tissue losses caused by trauma or burning in the tissue engineering approach. As known, bacterial infections should be minimized during the healing of wounds. For this purpose, the wound dressing films were synthesized with microcapsulated ginger extract which possess antioxidant activity to be gained antibacterial properties. Ginger extracts were obtained by extraction from ginger, then the extract were mixed with sodium alginate, and the solution were dripped into calcium chloride solution to synthesize microcapsules. The dressing material was prepared in the form of a hydrogel film based on silk fibroin/chitosan/gelatin by using solvent casting method in the presence of a crosslinker. The hydrogel films were characterized by FTIR, and the bacterial activities and cytotoxicity studies were carried out. The antibacterial activity of the film was tested by an inhibition zone method. Umbilical cord-derived mesenchymal stem cells (MSCs) were used to determine cytotoxic effect of the hydrogel films. As a result, the developed wound dressing films have a promising dressing materials for biomedical application because of its enhanced antibacterial activity and low cytotoxicity. Presentation mode Poster presentation

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Abstract ID 81 Title Functional fibrin-based hydrogels for controlling cell/biomaterial interactions in biohybrid implants Author(s) Prof. Dr. rer. nat. Andrij Pich1 2

P / Miriam Al Enezy-Ulbrich1 2 C

/ Svenja Wein3 4 / Hanna Malyaran3 4 / Nicole Terefenko1 2 / Karl Martin Graff1 2 / Norina Labude3 4 / Prof. Dr. rer. nat. Sabine Neuss3 4 C: Corresponding author P: Presenting author Affiliation(s) 1 Institute for Technical and Macromolecular Chemistry, Research Area Functional and Interactive Polymers, RWTH Aachen University 2 DWI - Leibniz Institute for Interactive Materials, RWTH Aachen University 3 Helmholtz Institute for Biomedical Engineering, BioInterface Group, RWTH Aachen University 4 Institute of Pathology, RWTH Aachen University Content Today’s implant research focuses on the enhancement of both their biocompatibility and reproducibility. Even though cardiovascular implants are commonly used, they only have a limited lifetime which also affects their properties and functionality.[1,2] Many research activities face the optimisation of implant properties. Formation of blood clots in mechanical implants (heart valves), bacterial biofilms (dental implants) or the degradation of bioprotheses should be prevented.[3–5] Also, the organ implant may still be rejected by the patient’s body.[6] The aim of this work is the synthesis of a biohybrid heart valve with a fibrin-based gel-matrix with textile reinforcement. The goal is to design a functional tool-box for fibrin-based biohybrid hydrogels to allow patient-specific individualisation of implants. The analysis of the biohybrid hydrogels will focus on the mechanical properties and morphology of the gels as well as on the cell/biomaterial interactions and the long-term behaviour of the cells in the biohybrid implant. All gels consist of natural fibrin and synthetic linear reactive copolymers based on poly(N-vinylpyrrolidone; Figure 1). This gel serves as an extracellular matrix for human stem cells which are cultured on and in the hydrogel. For this reason, the compatibility of the hydrogel is analysed regarding to viability, proliferation, apoptosis and necrosis behaviour and cytotoxicity. Also, the hydrogel’s properties have an influence on stem cell differentiation with respect to adipogenic, osteogenic, chondrogenic and myogenic differentiation (Figure 2). First experiments have shown that the use of copolymers have a high impact on the hydrogel’s properties and their long-term stability. To analyse that influence a variety of copolymers was synthesised, varying in their chemical composition, functional groups and molecular weights. The addition mode of the components (fibrinogen, copolymer, thrombin) and their ratios also play an important role in the hydrogel synthesis. Additionally, the copolymer binds to both, fibrinogen and fibrin. Softer gels can by synthesised without thrombin. We demonstrate that the synthesised gels show differences in their pore size, their storage modulus and their stress-strain behaviour. Long-term stable hydrogels also support the proliferation behaviour of human stem cells. This enables the myogenic differentiation of the cells on the hydrogels. The pore size of the hydrogels was analysed by using different microscopy and staining methods, while the characterisation of the mechanical properties was conducted by using rheology. First experiments show that the hydrogels which were synthesised with 3 mol% comonomer and the pure fibrin gel demonstrate strain-softening behaviour. Future experiments will deal with the synthesis of hydrogels with copolymers of high molecular weight to see whether they develop a strain-stiffening behaviour. Apart from that it will be interesting to analyse the implants in vitro to predict their behaviour after transplantation in vivo.

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[1] Baron, T. H., Kamath, P. S. & McBane, R. D. Management of Antithrombotic Therapy in Patients Undergoing Invasive Procedures. N. Engl. J. Med. 368, 2113–2124 (2013). [2] Siracuse, J. J. et al. Prosthetic graft infections involving the femoral artery. J. Vasc. Surg. 57, 700–705 (2013). [3] Baril, D. T. et al. Outcomes of lower extremity bypass performed for acute limb ischemia. J. Vasc. Surg. 58, 949–956 (2013). [4] Manji, R. A., Menkis, A. H., Ekser, B. & Cooper, D. K. C. Porcine bioprosthetic heart valves: The next generation. Am. Heart J. 164, 177–185 (2012). [5] Iyer, A. et al. Early Postoperative Bioprosthetic Valve Calcification. Hear. Lung Circ. 22, 873–874 (2013). [6] Shinoka, T. & Miyachi, H. Current Status of Tissue Engineering Heart Valve. World J. Pediatr. Congenit. Hear. Surg. 7, 677–684 (2016).

Presentation mode Poster presentation

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Abstract ID 90 Title Innovative flow chemistry for sustainable formulations Author(s) Dr Raphaël Riva1 C P / Dr Jean-Christophe Monbaliu1 / Dr Daniel Molin2 / Prof Christine Jérôme1 C: Corresponding author P: Presenting author Affiliation(s) 1 University of Liège 2 Maastricht University Content IN FLOW is an innovative cross-border R&D project involving 4 EMR cutting-edge partners in the fields of biochemical product formulation, characterization and engineering. The main R&D challenge of IN FLOW is to introduce new formulation technologies that allow fast and cheap degradable packaging of e.g. drugs in pills or creams. Our applied methodologies will allow companies to create novel high potential products for e.g. health- and personal care industry. The knowledge and technology that will be developed in IN FLOW provides public and private actors full advantages to fasten market introduction of their products. Our IN FLOW technology makes use of sophisticated in-house designed devices and know-how to create novel product formulations of (bio)degradable carriers loaded with ingredients with high efficiency. These carriers can be used as compounds in end-products like pills with direct applicability in healthcare, nutraceutical, cosmetic and pharmaceutical industries. The 3 main IN FLOW objectives are: 1- The development of the IN FLOW Community and Open Technology Platform: To ensure sustainability of the IN FLOW technologies, an Open Technology Platform will be established. This Platform includes all technology, protocols, and formulations of the IN FLOW portfolio. All IN FLOW hardware and facilities required for end-product production and validation will be made available for collaboration with companies, during and after the running-time of the project through this platform. 2- Creation of knowledge, infrastructure and best practice: Our second objective is to develop the IN FLOW R&D infrastructure, technologies and protocols for the production of the biodegradable carriers. By focusing on product innovation with a market-driven R&D approach and investments in facilities and protocols to upscale production to industrial level, a strong asset for supporting industrial R&D and market introduction is secured. 3- Creation of final products following public-private innovation trajectories: IN FLOW R&D revolves around 7 innovation trajectories with IN FLOW technology being applied to synthesize degradable biomaterials that answer to market demands of end-users. Added value of the cross-border collaboration for IN FLOW is provided by the BioMIMedics input generated by RWTH DWI, CERM ULiège and UM. In continuing this cross-border collaboration and enforcing the industrialization potential by partnering with Sirris, a strong consortium is created. Via a market-driven approach (trajectories), defined by private end-users (SMEs) through the open technology platform, IN FLOW will create innovative products and technologies. By combining unique EMR know-how, technologies and state-of-the-art infrastructures in an open innovation platform, IN FLOW proactively creates synergy for higher scale capacity for all actors. Presentation mode Poster presentation

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Abstract ID 65

Title Cellulose Aerogel Fibers: Development of a Multi-Functional Wound Dressing Author(s) Mr Matin Rostamitabar1 P C / Ass.Prof Samaneh Ghazanfari1 / Prof. Gunnar Seide1 / Prof. Stefan Jockenhoevel1 2 C: Corresponding author P: Presenting author Affiliation(s) 1 Aachen-Maastricht Institute for Biobased Materials (AMIBM), University of Maastricht 2 Institute of Applied Medical Engineering, RWTH Aachen Content Introduction: Porous cellulose aerogel fibers having high porosity, low density and high specific surface area can be a suitable material to design multi-functional wound dressings. The structure of the nano-porous network inside the fibers can be tuned based on the release profile of each bio-active agent that covers a particular phase of the wound healing process. After fiber production, gas anti-solvent crystallization inside the pores by supercritical CO2 will be applied to create fibers with different morphologies and to load them with different bio-active agents. Then, loaded fibers with specified morphological characteristics containing different agents and non-loaded fibers to provide thermal insulation and drainage of wound exudate will be assembled together as non-woven. In this study, material characterization, fiber spinning and cytotoxicity of spun alcogel fibers were investigated. Materials and Methods: Calcium thiocyanate tetrahydrate (Ca(SCN)2·4H2O) (>95%) and two different types of cellulose powder, medium (C) and highly purified (S), were used for preparing the solution. Samples were washed with the absolute ethanol (all from Sigma Aldrich). -Material characterization: The viscometry of cellulose samples showed that the degree of polymerization for the cellulose type C and S was 159 and 800, respectively. Size exclusion chromatography for the precise result was carried out with the calibration of pullulan standards. -Production of cellulose solution and alcogel fibers: The salt melt hydrate system of Ca(NCS)2·xH2O (x≦4)+yH2O (y≦6) [1] is able to dissolve cellulose (1-6% wt.) at 110 °C, and it can be spun by the extrusion or wet-spinning method. Dissolution of the cellulose takes 10-60 min depending on the cellulose Mw, concentration and the final temperature. A stable gel was formed below 80◦C and evaluated by the temperature sweep test. The fibers were spun by a micro-extruder [2] and wet-spinning unit. The ethanol bath was used for the regeneration and coagulation. To remove residual salt from the fibers, they were washed in fresh absolute ethanol for a week. -Cytotoxicity test: To investigate the effect of the processing parameters, drying and drug loading on the fiber cytotoxicity, they should be evaluated gradually. As a result, the cytotoxicity of the cellulose powders ( Cs , CC) and the alcogel fibers (Fs, FC) on the skin fibroblast cells were evaluated by the XTT assay [3]. Results and discussion: The SEC data showed Mw of 149.3 kg/mol and PDI of 6.146 for type C and Mw 374.7 of kg/mol and PDI of 14.19 for type S. Furthermore, opaque white alcogel fibers with diameter of 0.5 and 1 mm were produced. After washing steps, they were dried in ambient temperature, leading to xerogel formation of the fibers. In addition, the cells stayed viable when cultured with both powders and fibers. The proliferation of the fibroblast cells in cellulose powders happened only in Cs as it was highly purified. However, the viability of Fs was lower than Fc due to the presence of the trapped salt between the longer chains of Cs. The SEM images of the Fs proved the presence of the trapped salt between the chains of the fibers. Therefore, to improve the washing step efficiency, ion-exchange resins should be used. In the next steps, fibers can be loaded and dried with supercritical CO2. [1] Hattori, M., et al., Polymer Journal, 1998. 30: p. 43. [2] Karadagli, I., et al., the Journal of Supercritical Fluids, 2015. 106: p. 105-114. [3] Roehm, N.W., et al., Journal of Immunological Methods, 1991. 142(2): p. 257-265.

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Abstract ID 125 Title Enzymatically depolymerizable thermosets based on renewable bis(pyrrolidone) dicarboxylic acids with bis(2-oxazoline)s: A potential route towards chemical recycling Author(s) Mrs. Manta Roy1 C P / Asst. Prof. Dr. Karel Wilsens1 / Prof. Dr. Sanjay Rastogi1 C: Corresponding author P: Presenting author Affiliation(s) 1 Maastricht University Content Adding to the circularity of polymers, we report on the synthesis of functional mono and aliphatic bis(pyrrolidone)based dicarboxylic acid (BPD) monomers, starting from renewable itaconic acid and various diamines/naturally occurring amino acids. These monomers are used as component in thermally curable and enzymatically depolymerizable bis(2-oxazoline) resins. The BPD monomers are synthesized in bulk using aza-Michael addition of a diamine and two equivalents of itaconic acid. This synthesis and purification route is considered green as it uses no solvents resulting in >99% purity and >95% yield. Through NMR, GPC, DSC and FTIR analysis, we demonstrate that these BPD monomers exhibit significantly enhanced curing rates in 2-oxazoline resins compared to aliphatic dicarboxylic acids. We observe that the rate of 2-oxazoline ring opening addition with carboxylic acid functionalities is determined by dicarboxylic acid, whereas the ring opening addition of the 2-oxazoline functionality with amide groups is determined by bis(2-oxazoline) compound.[1] Overall, the used procedures provide excellent control over reaction chemistry, temperatures, and chemical composition of the cured materials. Additionally, the thermosets obtained after curing proved to be plasticized by water, thereby facilitating a brittle to ductile transition in their mechanical response. Although hydrolysis proceeds at a sufficiently slow rate to not affect the mechanical response for at least one month, it is also the hydrolysis of ester bonds and partially the secondary amide bonds that allows for chemical recycling of the BPD monomers. As a consequence, BPD monomer crystallizes from solution, allowing for chemical re-use. These features are demonstrated through rheology, DMTA(dynamic mechanical thermal analyser), DSC, GPC, LC-MS and micro tensile testing. Followed by chemically recycling the renewable bis pyrrolidone monomers, the rest over crosslinked networks of secondary and tertiary amide bonds could potentially be enzymatically degradable with the enzymes found in soil. These thermosets might find its potential usage where slow and controlled release of functionalized carboxylic acids is desired over time. One potential application lies in the field of adhesives, or in the field of tissue regeneration. In collaboration with Chemelot Innovation and Learning Labs (CHILL) for supporting in the material analysis. This project has received funding from the INTERREG V program Flanders-Netherlands (Puur Natuur: 100% Biobased), the cross-border collaboration program financially supported by the European fund for regional developement. [1] Roy, M.; Noordzij, G. J.; van den Boomen, Y.; Rastogi, S.; Wilsens, C. H. R. M. Renewable (Bis)Pyrrolidone Based Monomers as Components for Thermally Curable and Enzymatically Depolymerizable 2-Oxazoline Thermoset Resins. ACS Sustain. Chem. Eng., 6 (4), 5053–5066, (2018) Presentation mode Oral presentation & poster presentation

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Abstract ID 63 Title Enzymatic conversion of chitin into high value functional oligosaccharides Author(s) Christian Schmitz1

P / Dr Stefan Rasche2 1 / Ass. Prof Luisa Bortesi1 C C: Corresponding author P: Presenting author Affiliation(s) 1 Aachen-Maastricht Institute for Biobased Materials, Maastricht University 2 Fraunhofer Institute for Molecular Biology and Applied Ecology IME Content Chitin is the second most abundant polysaccharide in the world and typically emerges as a by-product in food industry during the processing of marine crustaceans. Despite its limited natural scope of applications, chitin is getting increasing attention in medical, agrochemical, food and cosmetic industry as it can be converted to the highly bioactive derivatives chitosan and chitosan oligomers (COS), that exhibit structure-function related properties such as anti-bacterial, -fungal,- inflammatory and -tumor effects. Current chemical COS production processes pose a high environmental burden due to the excessive use of acidic and basic reagents, are hardly controllable with regards to product properties in terms of degree of polymerization and degree of acetylation and require extensive purification efforts for the removal of harmful reactants. Recently, less-detrimental approaches that integrate an enzymatic conversion by means of chitinases and/or chitosanases, and chitin-deacetylases have been proposed as the reaction mechanisms are better controllable and furthermore yield defined chitosan and COS mixtures. Within the Aachen-Maastricht Institute for Biobased Materials (AMIBM), an enzymatic In-vitro conversion process of chitin will be developed to generate defined COS. These products will then be utilized as coating agents to functionalize novel technical and medical products using AMIBM infrastructure. The basis for the process development is a novel marine microorganism (designated „Chi5“) ¬¬secreting a mixture of chitinases and chitin-deacetylases. After recombinant enzyme production and characterization, an In-vitro enzyme cocktail will be established using the Design-of-Experiments (DoE) approach in order to generate defined chitosan-oligomers. Sequencing of the „Chi5“ genome was carried out and the genes encoding five chitinases and five chitin-deacetylases were identified, cloned and expressed heterologous by Escherichia coli. Enzyme characterization and analysis of degradation products by means of degree of polymerization and degree of acetylation is currently ongoing.


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Abstract ID 146 Title Property Analysis of Poly(butylene adipate-co-terephthalate)/Polylactide Blends and Comparative Observation of Tear Propagation Test Methods Author(s) Mr Shen Su1

C P C: Corresponding author P: Presenting author Affiliation(s) 1 Fraunhofer UMSICHT, Fraunhofer Institute for Environmental, Safety, and Energy Technology, Oberhausen, Germany Content Biobased and biodegradable polymeric materials have increasingly drawn the attention of the public and plastic industry. Blending poly(butylene adipate-co-terephthalate) (PBAT) with polylactide (PLA) is a practical and economic method to achieve a combination of properties from both components. In this study, blend properties of pressed sheets, flat and blown films are investigated depending on the PBAT/PLA ratios, and the methods for tear propagation resistance of blown films are comparatively observed respectively. Firstly, PBAT/PLA blends were prepared using compounding extrusion. Secondly, the compounds were processed into pressed sheets, flat and blown films on labscale equipment. Subsequent, the thermal, morphological and mechanical properties of the test specimens were explored. The PBAT/PLA ratio affects the manufacturability and quality of blown films and flat films. Differential scanning calorimetry and scanning electron microscopy indicate that unmodified PBAT and PLA are immiscible. For evaluating the tear propagation resistance of blown films, results of Elmdendorf and trouser tear tests are compared with each other, and both test methods are discussed. Furthermore, tensile properties are analyzed relating to blend ratio and processing method. Finally, the mutual interaction of the polymer ratio, the manufacturability and preparation method as well as the mechanical properties are discussed. Presentation mode Poster presentation

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Abstract ID 114 Title Analyzing the sustainability impact of bio-based materials from a life-cycle perspective Author(s) Dr. Yvonne van der Meer1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 Aachen-Maastricht Institute for Biobased Materials (AMIBM), Maastricht University Content Bio-based materials are promising sustainable substitutes for fossil based materials. Biomass is an abundant renewable resource for bio-based materials, thereby creating a continuous loop of CO2 sequestration and CO2 emission with reduced greenhouse gas emissions. They also offer the option for (enzymatic) green production routes and can provide an additional waste stratregy, i.e. biodegradation. In addition, bio-based materials offer economic development potential for rural areas [1]. However, bio-based materials are not intrinsically sustainable. Sustainability issues like competition with food security and reduced biodiversity have already been identified and should be taken care of when further developing the bio-based economy [2]. Hence, sustainability assessment is essential to develop bio-based materials that are also sustainable. Life Cycle Assessment (LCA) is a recognized and standardized methodology [3] to quantify the environmental impacts of a product. LCA considers the entire life cycle of a product and is a valuable tool to avoid shifting environmental impacts from one life cycle stage to another stage. LCA also supports decision makers to avoid creating a new environmental issue while solving an environmental issue. Bio-based materials generally show a lower climate change impact, but only if greenhouse gas emissions from indirect land use change are not taken into account [4]. Furthermore, bio-based materials may have higher environmental impacts in other impact categories, such as eutrophication [4]. Therefore, it is of vital importance to assess the environmental impact and to include the environmental performance of bio-based materials when expanding the industrial production of bio-based materials [4,5]. Our research portfolio comprises LCA studies of bio-based materials that are still under development at laboratory, pilot, or industrial scale. In this way, feedback loops with sustainability information are created to support the selection of the most promising options for further development towards novel or more sustainable bio-based materials. Investigating the full life cycle of a bio-based product reveals how the sustainability performance can be improved within the whole value chain. This contribution will present several LCA studies related to bio-based materials to illustrate how LCA can support the development of sustainable bio-based materials. This contribution will highlight the sustainability opportunities for bio-based materials as well as the challenges, such as sustainability issues related to the biomass feedstock. The current limitations of LCA will also be addressed. By developing a portfolio of LCA studies along the bio-based value chain, we aim to provide a solid framework for environmental impact assessment of bio-based value chains. Moreover, integration of environmental LCA with Life Cycle Costing provides a more comprehensive view on the full sustainability performance of bio-based materials.

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[1] J.W.A. Langeveld, J. Dixon, and J.F.Jaworski, Development Perspectives Of The Biobased Economy: A Review. Crop Sci., 50, S-142-S-151 (2010). [2] A. Elbehri, A. Segerstedt, and P. Liu, Food and Agriculture Organization of the United Nations Biofuels and the sustainability challenge: a global assessment of sustainability issues, trends and policies for biofuels and related feedstocks, Trade and Markets Division, Food and Agriculture Organization of the United Nations, Rome (2013). [3] International Organization for Standardization (ISO) Environmental management - Life cycle assessment: Principles and framework. ISO14040 (2006). [4] M. Weiss, J. Haufe, M. Carus, M. Brandão, S. Bringezu, B. Hermann, and M.K. Patel, A Review of the Environmental Impacts of Biobased Materials. J. Ind. Ecol., 16, S169–S181 (2012). [5] P. Pawelzik, M. Carus, J. Hotchkiss, R. Narayan, S. Selke, M. Wellisch, M. Weiss, B. Wicke, and M.K. Patel, Critical aspects in the life cycle assessment (LCA) of bio-based materials – Reviewing methodologies and deriving recommendations. Resour. Conserv. Recycl., 73, 211–228 (2013). Presentation mode Oral presentation

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Abstract ID 181 Title Investigation of supramolecular interactions between raft polymers and polyphenols by isothermal titration calorimetry Author(s) Susanne Braun 1 C P / Prof. Andrij Pich 1 2 3

C: Corresponding author P: Presenting author Affiliation(s) 1 DWI - Leibniz Institute for Interactive Materials, RWTH Aachen University, Forckenbeckstraße 50, 52074 Aachen, Germany 2 Institute for Technical and Macromolecular Chemistry, Research Area Functional and Interactive Polymers, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany 3 Aachen Maastricht Institute for Biobased Materials, Maastricht University, Urmonderbaan 22, 6167 RD Geleen, Netherlands Content hydrogen bonds, van der Waals, Coulomb and dipole-dipole interactions are forming structurally defined molecular assemblies.[1] In nature many mechanisms are based on spontaneous association via non-covalent forces. Especially for the approach of biomimicry it is of enormous interest to study and understand supramolecular interactions. A well-known biopolymer with the ability to store the information of our genome coded by a pattern of hydrogen bonds is deoxyribonucleic acid (DNA).[2] One method to characterize interactions between two components in aqueous solutions is isothermal titration calorimetry (ITC), a method by which a complete thermodynamic profile can be obtained by only one measurement. This label-free and non-destructive technique allows to determine the binding affinity (KD), the reactions stoichiometry (N), the enthalpy (ΔH) as well as the entropy (ΔS).[3] In this research we investigated the interactions of polyphenols with linear RAFT polymers, containing carboxy groups as acceptors for hydrogen bonds, by ITC. Polyphenols are reactive metabolites which are naturally occurring in plant-based foods. Many polyphenols are providing a lot of hydroxy groups for hydrogen bonding and are used to prepare nature inspired biomaterials.[4] A deeper understanding of the interactions between linear RAFT polymers and polyphenols may allow the realization of new and more efficient synthetic routes for the preparation of structures assembled by supramolecular interactions. One goal of supramolecular chemistry is the control of intermolecular, non-covalent interactions to achieve a storage of information on a molecular level.[2] Additionally, supramolecular chemistry is focusing on so called hostguest systems suitable for both selective catalysis and medical drug delivery systems.[5, 6] References [1] R. Eckel, R. Ros, B. Decker, J. Mattay, D. Anselmetti, Angew. Chem. 2005, 117, 489–492. [2] J-M. Lehn, Science 2002, 295, 2400–2403. [3] S. Vega, O. Abian, A. Velazquez-campoy, Methods 2015, 76, 99–115. [4] S. Quideau, D. Deffieux, C. Douat-Casassus, L. Pouysegu, Angew. Chem. Int. Ed. 2011, 50, 586–621. [5] D. J. Cram, J. M. Cram, Science 1974, 183, 803–810. [6] S. Kubik, Chem. unserer Zeit 2017, 51, 372–383. Presentation mode Poster presentation

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POLYMERS FOR DRUG DELIVERY AND DIAGNOSTICS AND TREATMENT Abstract ID 156 Title In vitro targeting of synthesized folic acid-conjugated poli(amino ester) based-hyperbranched polymeric nanoparticles Author(s) Assist. Prof. Dr Ayça Bal Öztürk1 2

C P / Ms Zeynep Püren Akgüner2 / Mr Sherif Domingo3 / Ms Tuğba Erol3/ Assist. Prof. Dr Hakan Darıcı4 2 / Associate Prof. Dr. Serkan Emik3 C: Corresponding author P: Presenting author Affiliation(s) 1 Department of Analytical Chemistry, Faculty of Pharmacy, Istinye University, Istanbul 34010, Turkey 2 Department of Stem Cell and Tissue Engineering, Institute of Health Sciences, Istinye University, Istanbul 34010, Turkey 3 Department of Chemical Engineering, Faculty of Engineering, Istanbul University, Istanbul 34320, Turkey 4 Department of Histology and Embryology, Faculty of Medicine, Istinye University, Istanbul 34010, Turkey Content Cancer is one of the major diseases in the worldwide. Current antitumor agents are restricted during the chemotherapy due to their high toxicity, poor solubility in aqueous media and low specificity, leading to systemic toxicity and severe side effects. Development of targeted drug nanocarriers enhance the undesirable effects of anticancer drugs and also selectively deliver them at a sustained rate directly to cancerous tissues. In this work, we developed pH sensitive tumor-targeted nanoparticular drug delivery platform based hyperbranched poly(amino ester) as core part and poly(ethylene glycol)-b-poly(ε-caprolactone) diblock polymers as shell part, in which folic acid was conjugated on surface of hyperbranched polymer. Nanoparticles with dimensions of <100 nm was prepared by nanoprecipitation method. It was found that anti-cancer drug release from nanoparticles at pH 5.5 was found to be faster than pH 7.4 due to pH sensitive nature of the polymeric system. Blank and drug loaded nanoparticles were tested for their targeting and anticancer properties on L929 mouse fibroblast cell lines and HeLa (human cervical cancer cells) cell lines cancer cell lines with the help of MTT assay. Cellular uptake studies showed that the developed nanoparticles were successfully internalized in folate receptor overexpressed cancer cells, but not in normal cells. As a result, our all results showed that the developed nanoparticular system could be used as a potential drug carrier for the targeted cancer therapy.

Acknowledgment: This work supported by Turkish Scientific and Technical Research Council (TUBITAK) (Grant No: 117Z732).


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Abstract ID 34 Title MEDWORM concept for a drug delivery & removal system Author(s) Industrial & architectural designer Rinus van den Berg1 2

C P C: Corresponding author P: Presenting author Affiliation(s) 1 DSM 2 ex DSM designer Content Medworm is a concept for a flexible steer able needle, a kind of "robot", that can perform various functions inside the human body. Medworm is an extension of existing catheter technology and follows the trend for minimal invasive operations. Medworm is a concept in which a variety of technologies comes together…like advanced materials and coatings, new DES concepts, micro-electronics and patient specific device control systems. It is a logic step from existing methods to perform surgical operation in a human body via arteries. In this sense the artery is used as a passage/road to get access to the targeted area. Medworm is an "extension" of this concept but is able to move through the body outside the artery system. It can move through non virtual (f.i. muscles) & virtual spaces (f.i. stomach, thorax, heart, brains). The flexible needle is steered by using a motion controller that actually drills and pushes itself into the human body to a specific spot. It uses a kind of Tom-Tom road map of the individual patients body based on a previous required MRI scan data. Presentation mode Oral presentation

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Abstract ID 169 Title Cells feel the beat Author(s) Dr Yashoda Chandorkar1 P C / Mr Arturo Castro Nava1 / Mr Sjören Schweizerhof1 / Mr Marcel van Dongen1 / Dr. Tamas Haraszti1 / Dr Jens Köhler1 / Dr Hang Zhang1 / Dr. Reinhard Windoffer2 / Dr Ahmed Mourran1 / Prof. Dr. Martin Möller1 / Prof. Dr. Ing Laura de Laporte1 3 C: Corresponding author P: Presenting author Affiliation(s) 1 DWI Leibniz Institute for Interactive Materials e.V. Aachen, Germany 2 Institute of Molecular and Cellular Anatomy, Uniklinik, RWTH Aachen University 3 ITMC Institute of Technical and Macromolecular Chemistry, RWTH Aachen University Content https://www.nature.com/articles/s41467-019-11475-4 Presentation mode Oral presentation

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Abstract ID 121 Title An infusion method for encapsulating lipophilic components into V-type granular cold-water swelling starch Author(s) Prof. Bart Goderis1 C P / Dr. Dorien Dries1 / Prof. Jan Delcour1 C: Corresponding author P: Presenting author Affiliation(s) 1 KU Leuven Content Recently KU Leuven research groups introduced a method to produce granular cold water swelling starch (GCWSS) [1]. Heating native granular starch in aqueous ethanol leads to disruption of the native crystallinity and conversion of the amylose (AM) fraction to V-type crystals. Solvent removal produces granules containing V-type crystals with empty AM single helices. Exposure to (cold) water induces crystal melting and a prompt granular swelling, which in turn causes an increase of the viscosity of the aqueous medium. It was furthermore demonstrated that when GCWSS is exposed to suitable ligands in aqueous alcohol, the ligands tend to infuse within the previously empty V-type AM helices [2,3]. Such complexes might be considered as drug delivery systems. For instance, AM complexed with salicylic acid, menthone and menthol, ibuprofen, warfarin, genistein, and esters of vitamins and fatty acids have been produced for controlled release purposes [4]. The formation of AM inclusion complexes can protect these bioactive compounds during their passage through the stomach, and be released in the small intestine by the enzymatic hydrolysis of AM [4]. The advantage of using the KU Leuven infusion method over classical preparation methods is that the infusion method does not rely on harsh chemicals and that it is rather fast. Moreover, inclusion is realized at low temperatures, which is an advantage for thermally unstable ligands. In a feasibility study, ascorbyl palmitate (AscP) was used as a model guest compound. The impacts of temperature and ethanol and AscP concentrations on encapsulation performance were investigated. First, native maize and potato starches were converted into V-type GCWSS by aqueous ethanol treatment at 95 °C. Exposing GCWSS to AscP induced the formation of inclusion complexes. Maximum degrees of AscP encapsulation were 2.9 and 1.5% (w/w) for maize and potato starch, respectively, as determined by proton nuclear magnetic resonance measurements. As maize GCWSS contained more ‘parent’ V-type crystals, it was capable of entrapping more AscP than potato GCWSS. A Trolox equivalent antioxidant capacity test allowed verifying that encapsulated AscP still had substantial antioxidant capacity (up to 70% of that of free AscP). [1] D.M. Dries, S.V. Gomand, B. Goderis, J.A. Delcour, Carbohydrate Polymers (2014), 114, 196-205. [2] D.M. Dries, S.V. Gomand, S.C. Pycarelle, M. Smet, B. Goderis, J.A. Delcour, Carbohydrate Polymers (2017) 165, 229-237. [3] D.M. Dries, L. Knaepen, B. Goderis, J.A. Delcour, Carbohydrate Polymers (2017) 165, 402-409. [4] L. Zhang, H. Cheng, C. Zheng, F. Dong, S. Man, Y. Dai, P. Yu, Journal of Drug Delivery Science and Technology (2016), 31, 101-107. Presentation mode Oral presentation

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Abstract ID 30 Title Star-shaped polypeptides as efficient gene delivery platform materials in scaffold guided bone regeneration Author(s) Prof Andreas Heise1 C P / Prof Sally-Ann Cryan1 / Prof Fergal O'Brien1 C: Corresponding author P: Presenting author Affiliation(s) 1 Royal College of Surgeons in Ireland (RCSI) Content The field of tissue engineering is increasingly recognizing that gene therapy can be employed for modulating in vivo cellular response thereby guiding tissue regeneration. However, the field lacks a versatile and biocompatible gene delivery platform capable of efficiently delivering transgenes to mesenchymal stem cells (MSCs). In this paper we describe the systematic exploration of architectural variations of star-shaped poly(L-lysine) polypeptide (star-PLL),1 derived from the ring-opening polymerization of N-carboxyanhydride (NCA) with varying number and length of poly(L-lysine) arms as potential nonviral gene delivery vectors for MSCs. We demonstrate that star-PLL vectors are capable of self-assembling with pDNA to form stable, cationic nanomedicines. Moreover, the feasibility of starPLL polyplexes is demonstrated in vivo for the healing of large, critically sized, segmental bone defects, which remains an unmet clinical need in modern orthopedic medicine. The approach utilizes starPLL/pDNA loaded biomaterial scaffolds as 3D templates to guide the regenerative process.


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Abstract ID 85

Title Hyperbranched Poly (N-Vinylcaprolactam): Tuning Architecture and Thermoresponsivity in Water Author(s) Anna Holzberger1 2

P C / Dr. rer. nat. Andrea Scotti3 / Dr. rer. nat., Univ Prof Walter Richtering3 / Dr. rer. nat., Univ Prof Andrij Pich1 2 C: Corresponding author P: Presenting author Affiliation(s) 1 DWI – Leibniz-Institut für Interaktive Materialien e.V. 2 RWTH Aachen Institut of Technical and Macromolecular Chemistry 3 RWTH Aachen Institute of Physical Chemistry Content Hyperbranched polymers (HP) can be placed between linear polymers and dendrimers in terms of their degree of branching, chain entanglement and viscosity, tapping into areas such as supramolecular chemistry, biomaterials and coatings.[1] HP can be readily produced via one-pot reactions, e.g. Reversible-Addition-Fragmentation Transfer (RAFT) polymerisation techniques. In this way, hyperbranched poly (N isopropylacrylamide) and derivatives, displaying Type II demixing behaviour in water, have been successfully synthesised, including end-group functionalisation with peptides.[2] However, hyperbranched analogues of poly (N vinylcaprolactam) (PVCL), which has a concentration- and molecular weight dependent phase transition behaviour in water,[3] remain unreported. Here, we investigate the first synthesis of hyperbranched PVCL using a xanthate-based chain transfer monomer, yielding molecular weights between 3 000 and 40 000 Da at typical polydispersities reported for this method. The characterisation included size exclusion spectroscopy, nuclear magnetic resonance spectroscopy, static light scattering, and small angle neutron scattering. Turbidity measurements using UV/Vis spectroscopy showed that the hyperbranched structures collapse and aggregate upon heating at 34 – 37 °C, lower temperatures than those reported for linear PVCL (around 42° C at comparable molecular weights). Whilst closing the gap between linear and highly branched architectures, the ability to tune the thermoresponsiveness of these structures around physiological temperatures makes them highly relevant for applications in the biomedical field. Furthermore, the ability to modify the xanthate end groups will allow to further tune solution behaviour of these structures, making them promising candidates for supramolecular chemistry. [1] Zheng, Y.; Li, S.; Weng, Z.; Gao, C. Hyperbranched Polymers: Advances from Synthesis to Applications. Chem. Soc. Rev. 2015, 44, 4091. [2] Swift, T.; Lapworth, J.; Swindells, K.; Swanson, L.; Rimmer, S. pH Responsive Highly Branched poly(N-Isopropylacrylamide) with Trihistidine or Acid Chain Ends. RSC Adv. 2016, 6 (75), 71345–71350. [3] Peng, H.; Kather, M.; Rübsam, K.; Jakob, F.; Schwaneberg, U.; Pich, A. Water-Soluble Reactive Copolymers Based on Cyclic N-Vinylamides with Succinimide Side Groups for Bioconjugation with Proteins. Macromolecules 2015, 48 (13), 4256–4268.

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Abstract ID 72 Title In situ forming hydrogel for sustained intraocular drug delivery Author(s) Ms Blessing Ilochonwu1 P C / Dr. Marko Mihajlovic1 / Dr. Tina Vermonden1 C / Prof. Wim Hennink1 C C: Corresponding author P: Presenting author Affiliation(s) 1 Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University Content INTRODUCTION Retinal diseases are the leading cause of visual impairment worldwide. Delivery of therapeutic proteins to the posterior segment of the eye faces significant challenges including frequent intraocular injections, related adverse effects and high costs of the treatment. The effectiveness of antibodies or antibody fragments has been shown, but despite the clinical success, achieving effective concentrations at the target tissue for an extended period is often challenging. This research project aims to design “in situ” forming hydrogels, which can be easily injected in the vitreous cavity close to the retina using a small needle. After injection, the polymeric solution undergoes a phase transition to form a cross-linked hydrogel at the site of administration, entrapping bioactives which will then be released over a prolonged period. In this study, Diels–Alder click reaction is used to cross-link two different polymers. Hyaluronic acid-based polymers bearing furan groups were successfully crosslinked with four arm-PEG10K-maleimide (4APM) yielding stable hydrogels. Rheological analysis and degradation studies were performed to investigate the physicochemical properties of the gels. The potential use of this hydrogel system for ocular applications was shown by testing the cytocompatibility to retinal cells, injectability to the vitreous, and sustained release of a therapeutic protein. RESULTS & DISCUSSION 1. Hydrogel characterization, injectability, cytocompatibility and release profile Hyaluronic acid (HA) with a molecular weight of 20kDa was successfully modified with furan functional groups (FU) to obtain a hyaluronic-furan polymer (HAFU). HAFU-4APM hydrogels were prepared by mixing an aqueous solution of HAFU and four arm-PEG10K-maleimide at physiological conditions to obtain transparent hydrogels. Network formation was visualized at 37ᴼC by a lack of flow upon tilting the vial upside down after 8-75 minutes depending on the polymer concentration and degree of substitution. Rheological analysis showed rapid network formation in the hydrogels. Using different polymer concentrations (5 wt%, 10 wt%, 15wt% ) of HAFU-4APM DS57 hydrogels showed that the gelation time and hydrogel stiffness are strongly dependent on polymer concentration (figure 2B). The hydrogel solution could be easily injected to the vitreous body of a porcine eye through a 29G needle. Swelling and degradation analysis showed that the hydrogel system is degradable at physiological pH and temperature by retro-Diels Alder reaction; therefore, surgical procedures to remove hydrogel from the vitreous would not be necessary. Furthermore, hydrogel degradation and swelling rate can be tuned by varying the polymer concentration and degree of substitution. A cell viability assay of hydrogel, polymer and leachables on retinal Mϋller cells showed no toxicity at the used concentrations after 24-hour exposure. HAFU-4APM DS57 hydrogels 10%wt and 16%wt could sustain the delivery of bevacizumab for 30 and 35 days respectively. CONCLUSION We designed, synthesized and characterized suitable drug delivery systems based on “in situ” forming hydrogels, which can be easily injected in the vitreous cavity. The polymeric solution undergoes a phase transition at 37oC at physiological conditions to form a cross-linked hydrogel, entrapping bevacizumab as a model protein for the treatment of age related macular degeneration(AMD ) and diebetic retinophaty (DR).

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Abstract ID 120 Title Co-assembly of diblock and monoblock elastin-like polypeptides for preparation of micellar drug delivery carriers Author(s) Dr Duc H. T. Le1 2

P C / Prof. Dr. Jan C. M. van Hest3 C: Corresponding author P: Presenting author Affiliation(s) 1 Department of Biomedical Engineering, Eindhoven University of Technology 2 Department of Biochemistry, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Medical Center 3 Department of Biomedical Engineering & Department of Chemical Engineering, Eindhoven University of Technology Content Elastin-like polypeptides (ELPs) are a group of recombinant protein polymers composed of a repeating pentapeptide sequence (Val-Pro-Gly-Xaa-Gly)n or (VPGXG)n, where X is any amino acid residues except proline. Possessing thermo-responsive properties, ELPs reversibly coacervate via hydrophobic interactions to form ordered structures upon increasing temperature. The specific temperature at which the phase separation occurs is defined as the transition temperature (Tt), which is programmable precisely through the designed sequence lengths and/or introduction of guest residues at the X positions. The well-controlled stimuli-responsive properties, together with the biocompatibility, biodegradability, and non-immunogenic nature, attract a great interest from material scientists in using ELPs for developing “smart” nanocarriers for encapsulating drugs and controlled release at disease sites. ELPs with an amphiphilic diblock structure, composed of two ELP block components with distinct Tts, have been explored extensively as delivery carriers for their ability to form micellar nanoparticles. When increasing to a temperature in between the two Tts, one ELP segment with the lower Tt, defined as the hydrophobic block, becomes hydrophobic and coacervates while the other segment, defined as the hydrophilic block, remains soluble; as a result, the diblock ELP assembles into homogeneous micelles with sizes less than 100 nm. Applications of ELP micelles were demonstrated in vitro and in vivo as functional nanocarriers for loading drugs within the hydrophobic core and delivering at the tumor sites, as well as for presentations of photosensitizers, and/or targeting proteins at the micelle corona (Pille et al., Biomacromolecules, 2017). Here, we demonstrate a new strategy for preparation of micelles using co-assembly of a diblock and a monoblock ELP. The ELP sequences are denoted as [AxBy-m], where A and B are the guest residues, x and y describe the ratio between A and B, and m is the number of repeats. The diblock and monoblock ELP was designated as a [A3G2-60]-[V4F-50] and a [V4F-50] sequence, respectively. While [V4F-50] aggregates into submicron-sized particles at ~24ºC, [A3G2-60]-[V4F-50] self-assembles into micelles at ~ 30ºC. When the temperature of a [A3G2-60]-[V4F-50] and [V4F-50] mixture at 1:1 molar ratio in PBS was gradually increased to 37ºC, polydisperse particles were detected by Dynamic Light Scattering (DLS). On the other hand, rapidly raising the temperature induced the formation of homogenous micelles with a diameter of ~52nm (PdI: 0.05), the diameter of which is larger than the micelles from the diblock alone (~42nm). This indicates that the monoblock ELP co-assembles with the hydrophobic chain from the diblock to form larger micelles. To visualize the co-assembly phenomenon, we labeled [V4F-50] with Cy3 and Cy5 to obtain two different [V4F-50] probes; these fluorescently labelled monoblocks when combined into the co-assembled micelles, will exhibit the fluorescence resonance energy transfer (FRET) phenomenon from Cy3 (donor) to Cy5 (acceptor) because both are embedded within the hydrophobic core. The labeled monoblocks did not alter the formation of homogenous micelles with the diblock ELP, as confirmed by DLS. Furthermore, a mixture of [A3G2-60]-[V4F-50] and [V4G-50]-Cy3 and Cy5 rapidly heated to 37ºC exhibited an increase in emission from the acceptor (Cy5) when exciting the donor (Cy3). Interestingly, upon cooling to different temperatures, the co-assembled micelles responded to the thermal trigger by increasing their size, for example, to ~150 nm at 30ºC. This thermo-responsive property could be useful for controlled release of drugs. We are currently developing co-assembled systems with monoblock ELP-chemodrugs and/or photosensitizer conjugates for multifunctional

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nanoparticles for dual therapy. Together with nanobodies at the micelle corona that can navigate the ELP micelles towards target cancer cells, we aim to investigate the efficacy of the functionalized micelles in treatment of ovarian cancer using photodynamic and chemotherapies. Presentation mode Oral presentation & poster presentation

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Abstract ID 148 Title Photosensitizers Encapsulated in Polymeric Micelles for PDT: Opportunities and Challenges Author(s) Dr Cornelus F. van Nostrum1 C P / Ms Yanna Liu1 / Prof Wim Hennink1 C: Corresponding author P: Presenting author Affiliation(s) 1 Utrecht University Content Polymeric micelles are potentially suitable drug delivery systems for hydrophobic drugs that are otherwise not injectable [1]. Micelles are self-assembled nanostructures that have a hydrophobic core to accommodate the drug, and a hydrophilic shell to maintain colloidal stability in a biological environment. As such, polymer micelles are also interesting systems to encapsulate and deliver photosensitizers upon intravenous injection, for photodynamic therapy of a variety of diseases such as cancer and atherosclerosis [2]. Besides solubilisation of the photosensitizers, micelles could also be interesting for site-selective delivery by passive or active targeting of the micelles including the photosensitizer, which may improve the efficacy of the photosensitizer and decrease side effects such as skin toxicity. However, in order to successfully deliver the photosensitizer to the diseased site, one must be sure that the photosensitizer remains inside the micelles during circulation after injection, and preferably that the drug is released by a trigger once arrived at the site of action (i.e. at tumor tissue, or in macrophages at atherosclerotic plaques) [3]. Usually change in pharmacokinetics and biodistribution are the prime outcome parameters to indicate stability of drug-loaded nanoparticles. However, to prevent excessive use of animals, reliable in vitro measurements are required that carefully predict in vivo stability. We will show that asymmetric flow-field flow fractionation (AF4) may do the trick. Furthermore, we will show examples of ways to improve stability and enable triggered release of micelles loaded with photosensitizers. [1] H. Cho, T.C. Lai, K. Tomoda, G.S. Kwon, Polymeric micelles for multi-drug delivery in cancer, AAPS Pharm. Sci. Tech. 16 (2015), 10-20. [2] C.F. van Nostrum, Polymeric micelles to deliver photosensitizers for photodynamic therapy, Adv. Drug Delivery Rev., 56 (2004), 9-16. [3] J.W.H. Wennink, Y. Liu, P. Makinen, F. Setaro, A. de la Escosura, M Bourajjaj, J. Lappalainen, L.Holappa, J.B. van den Dikkenberg, M. al Fartousi, P. Trohopoulos, S. Yla-Herttuala, T. Torres, W.E.Hennink, C.F. van Nostrum, Macrophage Selective Photodynamic Therapy by Meta-Tetra(hydroxyphenyl)chlorin Loaded Polymeric Micelles: a Possible Treatment for Cardiovascular Diseases, Eur. J. Pharm. Sci., 107 (2017), 112-125. Presentation mode Oral presentation & poster presentation

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Abstract ID 8 Title Functional Responsive Microgels for Healthcare Applications Author(s) Prof. Dr. Andrij Pich1 2

C P C: Corresponding author P: Presenting author Affiliation(s) 1 DWI Leibniz institute for Interactive Materials e.V, RWTH Aachen University 2 Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University Content Aqueous polymer microgels exhibit unique properties like high chemical functionality, reversible deformability, surface activity, and stimuli-responsiveness. Synthesis of aqueous microgels can be performed in controlled way to tune their size and size distribution, chemical functionality, surface charge, swelling degree, and colloidal stability. Functional microgels can be used as building blocks for the preparation of nanostructured materials of different dimensions and complexity. This contribution will focus on use of aqueous microgels as building blocks for the development of new soft materials for healthcare applications. Different approaches for the functionalization and attachment of microgels to different surfaces were developed utilizing adsorption, use of anchoring peptides or formation of covalent bonds. Surface-anchored stimuli-responsive microgels influence size, speed and dynamics of focal adhesions as well as cell motility forcing cells to move along highly directional trajectories.1 The modulation of microgel swelling degree and mechanical properties by the temperature or spacing serves as an effective tool for the regulation of cell motility. Microgels functionalized by zwitterionic groups or oligoPEGs provide hydrogel films with excellent protein-repelling properties. The attachment of bio-active compounds to the microgel surface allows fabricating anti-bacterial implant coatings with excellent biocompatibility.2 Due to their open structure and compartmentalized interior, microgels can load different molecules by hydrophobic or electrostatic interactions acting as smart carriers for metal ions, drugs, peptides or proteins.3 Microgels are soft, degradable and adaptive containers what ensures their efficient penetration in cells and potential application as carriers for the intracellular delivery of doxorubicin to tumors.4,5,6 The small size and fuzzy microgel surface increase their circulation time in-vivo providing optimal conditions for diagnostics. Gadolinium-loaded microgels were successfully used as an effective positive contrast agent for enhanced MR imaging of cancer cells in vitro as well as a subcutaneous tumor model in vivo.7 Our study suggests that the developed gadolinium-loaded microgels could be applied as a promising contrast agent for T1-weighted MR imaging of diverse biosystems. [1] A. S. Sechi, S. Ullmann, J. M. G. Freitas, R. P. Takehara, P. Wünnemann, R. Schröder, M. Zenke, A. Böker, G. Aydin, S. Rütten, Andrij Pich, Adv. Mater. Interf. 2016, 1600455. [2] M. Kather, M. Skischus, P. Kandt, A. Pich, G. Conrads, S. Neuss, Angew. Chem. Int. Ed., 2017, 129, 2537-2543. [3] R. A. Meurer, S. Kemper, S. Knopp, T. Eichert, F. Jakob, H. E. Goldbach, U. Schwaneberg, A. Pich, Angew. Chem. Int. Ed. 2017, 129, 7486-7492. [4] A. Melle, A. Balaceanu, M. Kather, Y. Wu, E. Gau, W. Sun, X. Shi, A. Pich, J. Mater. Chem. 2016, 4, 5127-5137. [5] H. Peng, X. Huang, L. Weger, A. Götz, M. Karperien, A. Pich, J. Mater. Chem., 2016, 4, 7572-7583. [6] H. Peng, X. Huang, A. Melle, M. Karperien, A. Pich, J. Colloid Interface Sci., 2019, DOI: 10.1016/j.jcis.2019.01.049 [7] W. Sun, S. Thies, J. Zhang, C. Peng, G. Tang, M. Shen, A. Pich, X Shi, ACS Appl. Mater. Interf. 2017, 9 (4), 3411–3418. Presentation mode Oral presentation

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Abstract ID 102 Title Tough Hydrogels for Applications in Tissue Engineering Author(s) Prof Louis Pitet1 C P / Sofie Houben1 C: Corresponding author P: Presenting author Affiliation(s) 1 Hasselt University Content Hydrogels are polymer networks swollen with large quantities of water (~90 %). The properties that can be accessed by tuning the composition of synthetic hydrogels is extraordinarily versatile, owing to the vast array of available building blocks and diverse cross linking strategies. Owing to the structural and compositional variability, hydrogels are also ideally suited for use in medical devices and drug delivery. They are also aptly suited for applications in tissue engineering. However, mimicry of native tissues like cartilage requires exceptional mechanical properties. This is a formidable task. This work describes several approaches to tough hydrogels that are made in a single pot system, and are thus amenable for injection and 3D bioprinting. The synthetic approach can be adapted to afford a large variety of building blocks, and can be tuned accordingly. These hydrogels should be compatible with native biological tissues and are designed specifically to exhibit responsive physical properties. Presentation mode Oral presentation

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Abstract ID 141 Title Controlled release of drugs using a new kind of encapsulant material: gas Author(s) Dr Albert Poortinga1 C P / Dr Rodrigo Araya-Hermosilla2 / Dr Paolo Pescarmona3 / Prof Francesco Picchioni3 C: Corresponding author P: Presenting author Affiliation(s) 1 Eindhoven University of Technology 2 Universidad Tecnológica Metropolitana Chili 3 University of Groningen Content Numerous materials have been applied to encapsulate drugs for controlled release applications but until recently one barrier material has been overlooked: gas. We have developed a new encapsulation technology in which drugs are encapsulated inside microbubbles, i.e. the drug is shielded from the environment by a shell of gas, as shown in Fig. 1 (Langmuir 29 (2013) 8782−8787). These structures are referred to as antibubbles. A major advantage of these encapsulates over conventional encapsulates is the fact that a gas shell represents an insurmountable barrier for nearly all drugs (since drugs are generally non-volatile), regardless of their properties such as hydrophobicity, molecular weight, etc. On the other hand, when the gas shell is made to rupture in response to an environmental trigger the encapsulated drugs will be instantaneously and completely released, through a process comparable to the popping of a well-known soap bubble. This is because antibubbles are inherently unstable. We have solved this by adsorbing microparticles at the interfaces of the antibubbles (so-called Pickering stabilization) which leads to antibubble lifetimes of weeks. Controlled release can be obtained though the use of microparticles that are responsive. We have produced polylactide microparticles and used these to stabilize antibubbles. Over time the PLA microparticles degrade until the antibubbles become unstable and burst, thereby releasing their content in a pulsatile manner. Similarly, we have also obtained a pulsatile release at the beginning of the intestines for oral delivery applications. We will show results for the taste-masking of drugs and the protection against stomach pH of probiotics. These results show that antibubbles are excellent candidates for drug delivery. Presentation mode Oral presentation

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Abstract ID 88 Title Design of poly(HEMA) particles in supercritical carbon dioxide for protein delivery Author(s) Dr Raphaël Riva1 P C / Dr Rahmet Parilti1 / Mr Jérémie Caprasse1 / Prof Christine Jérôme1 C: Corresponding author P: Presenting author Affiliation(s) 1 University of Liège Content Since many decades, polymers proved to be excellent candidates for the development of drug carriers in the pharmaceutical field. Indeed, the range of biocompatible polymers available on the market place allows to prospect new developments of drug carriers for active principle. A vast majority of the polymer nanocarriers have been designed and developed for the controlled and targeted release of hydrophobic drugs. Indeed, the development of delivery systems allowing (i) the solubilization of poorly soluble drugs, (ii) their transport and (iii) selective release to a specific site is a major challenge in the pharmaceutical field. Therefore, several types of nanosized vehicles have been developed, typically nanoparticles, dendrimers, or self-assembling systems such as liposomes or polymer micelles. However, there are still some challenges to design appropriate carriers for the delivery of therapeutic proteins or peptides. Although the history of the protein/peptide-based drugs dates back to insulin production, they have taken great attention since the last decades due to their possible broad range of therapeutic applications. They might offer more specific and safer therapies in comparison to small molecules drugs. Nonetheless, their encapsulation remains challenging specially to preserve their specific structure and activity in the formulations. For this purpose, hydrogel particles (nano-/microgels) have emerged as promising polymer carriers for such proteins. This work focuses on the synthesis of nano-/microgels encapsulating therapeutic proteins and peptides in supercritical carbon dioxide which confers environmentally benign features to the synthesis method. More precisely, hydrogel particles were obtained by free-radical dispersion polymerization of 2-hydroxyethyl methacrylate (HEMA) in supercritical carbon dioxide in presence of a crosslinker and a suitable stabilizer. Typically, the stabilizer, a block copolymer presenting a CO2-philic and a hydrophilic block, have been especially designed to present a photocleavable bond at the junction of the two blocks with the purpose to remove the fluorinated block after particles synthesis and as a consequence allows the poly(HEMA) particles to swell in water. The optimization of the dispersion polymerization conditions led to well-defined cross-linked particles. The process was robust enough to incorporate a drug or a peptide to encapsulate in one-pot synthesis into the particle network. In a subsequent step such drug loaded particles were dispersed successfully in aqueous media and shown sustained release of their content. This was demonstrated notably for the release of a bactericidal peptide. Presentation mode Oral presentation

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Abstract ID 80 Title Design, Synthesis and Characterization of Fully Zwitterionic, Functionalized Dendrimers for Drug Delivery Applications Author(s) Esther Roeven1 2 C P / Dr. Luc Scheres2 / Dr. Maarten Smulders1 / Prof. Han Zuilhof1 C: Corresponding author P: Presenting author Affiliation(s) 1 Wageningen University 2 Surfix BV Content Dendrimers are an interesting class of macromolecules due to the high level of control over their architecture. The presence of internal cavities and the possibility for multivalent interactions have made dendrimers interesting candidates for various applications. More specifically, zwitterionic dendrimers modified with an equal number of oppositely charged groups have found use in in vivo biomedical applications. However, the design and control over the synthesis of these dendrimers remains challenging, in particular with respect to achieving full modification of the dendrimer. In this work we show the design and subsequent synthesis of dendrimers that are highly charged whilst having zero net charge, i.e. zwitterionic dendrimers that are potential candidates for biomedical applications. First we designed and fully optimized the synthesis of charge-neutral carboxybetaine and sulfobetaine zwitterionic dendrimers. Following their synthesis, the various zwitterionic dendrimers were extensively characterized. In this study we also report for the first time the use of X-ray photoelectron spectroscopy (XPS) as an easy-to-use and quantitative tool for the compositional analysis of this type of macromolecules that can complement e.g. NMR and GPC. Finally, we designed and synthesized zwitterionic dendrimers that contain a variable number of alkyne and azide groups that allow straightforward (bio)functionalization via click chemistry.


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Abstract ID 100 Title Bio-Inspired Selenium-modified Microgels Author(s) Mr Kok Hui Tan1 2

P C / Dr Tetiana Kharandiuk3 / Dr Roman Nebesnyi3 / Prof Igor Potemkin4 /

Prof Dan Eugen Demco1 2 / Prof Andrij Pich1 2 5 C: Corresponding author P: Presenting author Affiliation(s) 1 DWI - Leibniz Institute for Interactive Materials 2 RWTH Aachen University 3 Technology of Organic Products Department, Lviv Polytechnic National University 4 Physics Department, Lomonosov Moscow State University 5 Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University Content In recent decades, microgels has captured intensive attraction due to its facile functionalization and biocompatibility. Depending on the selection of comonomers during the microgels synthesis, the porosity, functionality and responsiveness to external stimuli can be tuned [1, 2]. In this work, we aimed to use Poly(N-vinylcaprolactam) (PVCL) microgels as a scaffold, incorporated with diselenide-containing comonomer to mimics the structure of glutathione peroxidase1 (GPx1). Glutathione peroxidase 1 (GPx1), the most abundant GPx enzyme found in many mammals is verified for its importance in biological system. The selenocysteine amino acid in GPx contributes to its highly efficient antioxidative properties by catalyzing the reduction of peroxides (ROOH) into water then with the recovery of catalyst by glutathione (GSH) and NADPH and thus, protecting the cellular membrane from oxidative damages [3]. With respect to this, the synthesized selenium containing PVCL microgels possess high chemical stability, porous structure and high catalytic properties as compared to GPx1. In the preliminary studies, the diselenide groups in PVCL microgels can be cleaved upon addition of hydrogen peroxide and glutathione resulting in seleninic acid and selenol groups respectively. The activity of the selenium groups were proven catalytically active during the investigation with a model catalytic reaction: oxidation of acrolein into acrylic acid or methyl acrylate in organic solvent medium. Next, the uptake and release of the selenium-modified microgels will be investigated. Acknowledgements: This authors acknowledge Volkswagen Stiftung for the project A115859. Thank to SFB 985 “Functional Microgels and Microgels Systems” for financial support. [1] F. A. Plamper and W. Richtering Acc. Chem. Res. 2017, 50, 131-140. [2] G. Agrawal and R. Agrawal Polymers 2018, 10, 418. [3] G. Mugesh, W.-W. du Mont and H. Sies Chem. Rev. 2001, 101, 2125-2180. Presentation mode Poster presentation

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Abstract ID 108 Title Nanoporous smectic liquid crystalline nanoparticles for drug delivery Author(s) Serena Teora1 P C / Xiaohong Liu2 / Albert P. H. J. Schenning2 / Cornelus F. van Nostrum1 C: Corresponding author P: Presenting author Affiliation(s) 1 Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University 2 Department of Chemical Engineering and Chemistry, Eindhoven University of Technology Content Introduction Liquid crystals (LCs) are the intermediate state of matter in which molecules possess fluidity like liquids and orientational order similar to crystals [1]. The capability of LCs to self-assemble in highly ordered structures and the possibility to fix that in a polymer network, make them interesting for the construction of nanostructured materials. Recently, the Schenning group has developed pH-responsive nanoporous LC polymer particles [2]. In this work, we investigated those particles as adsorbents for capture and pH-triggered release of the cationic model drug methylene blue (MB). Methods Particles were synthesized from two LC monomers, i.e. the hydrogen bonded dimer 4-(6-acryloxy-hexyl-1-oxy)benzoic acid (6OBA) and the covalent cross-linker 4-((4-(6-(acryloyloxy)hexyloxy)phenoxy)carbonyl) phenyl 4-(6-(acryloyloxy)hexyloxy) (C6H) in a 9/1 w/w ratio. The precipitation polymerization was carried out at 95°C, at which the monomer mixture is in the smectic liquid crystalline phase. This resulted in nanoparticles with a diameter of approximately 600 nm and with radial ordering of smectic LC layers [2]. Subsequently, pores were created by an alkaline treatment with 10 mM NaOH which converts the benzoic acid groups to benzoate groups and thus breaks the hydrogen bonds in the polymer network. The adsorption of cationic MB as a model drug was performed by exposure of the nanoporous particles to MB solutions. Solutions with different concentrations of nanoparticles in 10 mM NaOH were exposed to MB solution (1 mg/mL) keeping total volume constant. MB/carboxylate ratio were chosen between 0.1 and 1.4 considering the absorption is based on 1:1 ionic interactions [2]. The amount of dye absorbed has been quantified by UV-vis spectroscopy comparing the concentrations of the dye in solution before and after exposure. The occupation degree (mol/mol) is expressed as amount of dye per amount of carboxylate moieties. The MB release was carried out adding buffer solutions of different pH (3 - 7.4) to the LCs suspension loaded with MB. Results and Discussion The negative charge of pores of the nanoparticles as a function of pH has been confirmed by zeta potential values (figure 1). Results show a gradual decrease in the negative zeta potential when pH was decreased, in accordance to the gradual protonation of the benzoate groups. Moreover, particles at lower pH tended to aggregate, as a result of the diminishing of the repulsive electrostatic forces. A maximum occupation degree of 94% could be reached when the MB/carboxylate ratio was 1.3. The absorption kinetics was monitored over 24 hours revealing the equilibrium has been reached in 15 minutes. This suggests high affinity and fast diffusion of MB in the nanoporous nanoparticles. The desorption of the dye has been investigated over 48 hours at different pH (figure 2). Results showed burst release (within 10 minutes) that was strongly pH-dependent and mainly occurred at pH <7. This can be explained considering that the carboxylate moieties are protonated by lowering the pH, resulting in an efficient desorption of MB from the adsorbent.

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Conclusion Nanopores present in the smectically ordered polymer nanoparticles could adsorb MB with high capacity and fast kinetics by electrostatic and supramolecular interactions. In combination with the triggered release at pH <7 make those LC nanoparticles highly promising system for intracellularly drug delivery. [1] Mo, J.; Milleret, G.; Nagaraj, M. Liquid Crystals Reviews 2017, 5 (2), 69-85. [2] van Kuringen, H. P. C.; Mulder, D. J.; Beltran, E.; Broer, D. J.; Schenning, A. P. H. J. Polymer Chemistry 2016, 7 (29), 4712-4716.


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Abstract ID 140 Title Microgels as delivery system for plant health Author(s) Mr Alexander Töpel1 2

P C / Ms Wenjing Xu1 2 / Ms Liudmyla Goncharenko3 2 / Dr Felix Jakob3 2 / Prof Ulrich Schwaneberg3 2 / Prof Andij Pich1 2 C: Corresponding author P: Presenting author Affiliation(s) 1 Institute of Technical and Macromolecular Chemistry, RWTH Aachen University 2 DWI Leibniz Institute for Interactive Materials 3 RWTH Aachen University, Lehrstuhl für Biotechnologie Content Health starts with a healthy diet which requires a healthy and contamination free feedstock and plants. Therefor it is necessary to significantly reduce the amount of fertilizers and pesticides that are applied on the fields. The biggest challenges of the application of pesticides and fertilizers are beside the used amounts, the duration of their efficiency. A key performance parameter of applied plant protection agents is their rainfastness. Rainfastness describes the wash off of agents applied to the plants. Increasing the rainfastness will lead to reduced pesticide usage. To overcome these challenges, a system that provides a constant release of the active agent and with a rainfasten binding will be beneficial. Polymers as carrier systems have a high potential for this application. Especially stimuli responsive microgels seem to be a promising candidate as smart delivery system. Microgels are three dimensional crosslinked polymer networks which swell in water. They are biocompatible polymers making them an interesting candidate for health and environmental application. By changing the chemical composition of the polymer network different properties can be implemented leading to the possibility to design the microgel for certain applications. Different commoners can introduce charges, reactive groups, degradable properties or a hydrophobic character to the microgel. We already showed that microgels can be applied to release fertilizers to cucumber leaves resulting in a fertilizer uptake by the plant and regreening of the leaves.[1] To prove the general applicability we designed microgels for different agricultural applications. Therefor we synthesized microgels which are able to interact with peptides, ions and hydrophobic molecules (pesticides). We are able to control the loading and the release process. To achieve a rainfastness binding of microgels to leave surfaces, we decorated the microgel surface with anchor peptides that are designed and engineered to bind on specific target plants and locations (only on the leafs and not on the fruits). We claim that this will lead to a reduction of applied pesticides and fertilizers with no negative effect to the plant health or harvest amount. [1] R. A. Meurer, S. Kemper, S. Knopp, T. Eichert, F. Jakob, H. E. Goldbach, U. Schwaneberg, A. Pich, Angew. Chem. Int. Ed. 2017, 56, 7380. Presentation mode Oral presentation

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Abstract ID 76 Title Polyampholyte Microgels as Carriers for Controlled Protein Interaction Author(s) Ms Wenjing Xu1 2

P C / Mr Andrey Rudov3 1 / Prof.Dr Andrij Pich1 2 4 / Prof.Dr Igor Potemkin1 3 / Prof. Dr Walter Richtering5 C: Corresponding author P: Presenting author Affiliation(s) 1 DWI – Leibniz Institute for Interactive Materials 2 RWTH-Aachen University, Institute for Technical and Macromolecular Chemistry 3 Physics Department, Lomonosov Moscow State University 4 Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University 5 Institute of Physical Chemistry, RWTH Aachen University Content Polyampholyte microgels as carrier systems to entrap guest molecules like proteins, dyes or nanoparticles has been intensively studied in the past years and has attracted great attention especially in the field of biomedical application. These kind of smart materials are extremely interesting due to their facile functionalization and their high biocompatibility. Through the right choice of monomers during the microgel synthesis, the balance between hydrophilicity/hydrophobicity, the presence of charges and particle size at a specific pH, and the response to external stimuli can be tuned. Guest molecules can be attached to the microgel polymer network either by chemical (covalent) bounds or physical (electrostatic) binding. Chemical binding is often used if diffusional leaking is undesired and the release of the guest molecule is realized through the degradation of the whole polymer network. Physical binding offers the opportunity to use pH as an external stimulus to trigger the release of the payload from microgels.[1] In this work, we synthesized differently structured polyampholyte microgels with controlled amounts and different distribution of acidic and basic moieties as colloidal carriers to study the loading and release of the model protein cytochrome c (cyt-c). Polyampholyte microgels were first loaded with cyt-c using the electrostatic attraction under pH 8 when the microgels were oppositely charged with respect to the protein. Then the protein release was investigated under different pH (3, 6 and 8) both with experimental methods and molecular dynamics simulations. For microgels with a random distribution of ionizable groups complete and accelerated (compared to polyelectrolyte counterpart), the release of cyt-c was observed due to electrostatic repulsive interactions. For core-shell structured microgels with defined ionizable groups, it was possible to entrap the protein inside the neutral core through the formation of a positively charged shell, which acts as an electrostatic potential barrier. We believe that this discovery allows the design of functional colloidal carriers with programmed release kinetics for applications in drug delivery, catalysis, and biomaterials.[2] [1] Adv. Drug Deliv. Rev.,2002 (54), 135. [2] Biomacromolecules, 10.1021/acs.biomac.8b01775 Presentation mode Poster presentation

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Abstract ID 191 Title Tailor made metal-free copolymers for drug delivery applications. Synthesis and scale-up. Author(s) Dr. Pavel Bartovský1 P C / Dr. Amador García Sancho1 / Dr. Laura Martí Montaner1 / Dr. Rafael Alonso Ruiz1 / Dr. Josep García García1 C: Corresponding author P: Presenting author Affiliation(s) 1 AIMPLAS Content For a variety of biomedical applications, the versatility of biocompatible polymers provides a true treasure chest. Their characteristics made them ideal candidates for transport and controlled release of biologically relevant compounds. By encapsulating drugs, biomolecules or contrast agents, particles of uniform size, surface functionality, and adjustable kinetics of release can be generated. Besides polymeric nano and microparticles, hydrogels can be designed for sustained local drug delivery and application via injection for regenerative medicine and medical imaging among others. The recent advances in additive fabrication create a new opportunity to design personalized devices and structures by 3D-printing and 3D-bioprinting that are biodegradable and can release drugs in a sustained and controlled manner. Despite of the growing number of scientific publications, there is a huge gap between basic research and pharmaceutical industry that prevents or retards the transfer of improved therapies to market and to the patient. Some of the common drawbacks are process upscaling, reproducibility, repeatability together with good manufacturing practice and regulatory compliance. Polyesters are among of the most versatile and better described polymers with many possible applications in drug delivery. Despite their outstanding performance, they can present cytotoxicity due to the residues of metal catalysts. We hereby report on a new method for enzymatic synthesis and scale-up of tailor made polyesters free of metal contaminants. The aim of our approach is to replace the traditional metal catalysts such as tin (II) 2-hexanoate which cause cytotoxicity. Synthesis of PLA, PLGA and PCL under variable conditions were selected as model reactions. Different enzymes (lipases) were employed to catalyse ring opening polymerization (ROP) of the cyclic monomers. Efficiency, selectivity and activity of the enzymes were determined. One interesting option for up-scaling of the synthesis is to employ reactive extrusion. This technology can be performed in a semi-continuous and continuous mode and allows to produce the desired copolymers in semi-industrial up to industrial scale. The resulting material is usually very pure thanks to the low reaction time in the extruder comparing to the traditional synthesis. This prevents the undesirable degradation of the product by heat and humidity as well as depolymerization. As a proof of concept, the obtained copolymers were used for controlled delivery of biomolecules (antibodies, miRNAs), contrast agents and markers for medical imaging as well as patches for applications in tissue engineering. Pavel Presentation mode Oral presentation

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POLYMERS FOR PERSONAL CARE, MEDICAL DEVICES, HYGIENE AND MEDICAL PACKAGING Abstract ID 27 Title How will new key regulations impact your materials cocktail for packaging & medical devices? Author(s) Cecile Balloffet1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 Clariant Plastics & Coatings Content - Key regulations with deadlines in 2020 will have a profound and still ‘unknown’ effect, directly impacting assessments of plastics. - ICH Q3D and USP661.1 and MDR EU 2017/745 bring new requirements that could 'shake' the industry if not well prepared. - Packaging and medical devices supply chain will need evaluate the impact of the new regulations. - This presentation will focus on how you might avoid to be ‘stirred’ into last minute changes. - Clariant provides solutions with its MEVOPUR® and REMAFIN-EP compound and concentrate range already compliant and supported by full-time specialists (e.g. Majority of ingredients tested to USP661.1, 87,88 and ICHQ3D). Presentation mode Oral presentation

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Abstract ID 113 Title Synthesis of temperature- and pH-responsive microgels and their incorporation into electrospun PLA-fibres Author(s) Susanne Braun1 P

C / Catalina Molano López1 / Georg-Philipp Paar2 3 / Thomas Gries3 / Stefan Jockenhoevel2 / Andreas Blaeser2 3 / Andrij Pich1 4 C: Corresponding author P: Presenting author Affiliation(s) 1 DWI - Leibniz Institute for Interactive Materials, RWTH Aachen University 2 Dept. of Biohybrid & Medical Textile (BioTex), AME-Applied Biomedical Engineering, Helmholtz Institute Aachen, RWTH Aachen University 3 Institut für Textiltechnik of RWTH Aachen University 4 Institute for Technical and Macromolecular Chemistry, Research Area Functional and Interactive Polymers, RWTH Aachen University Content Accessibility of innovative materials in the field of modern life sciences and medical care are crucial for the development of new technologies. Nowadays, the commercially used materials for degradable sutures, osteosynthesis and drug delivery systems are polyglycolic acid (PGA) and polylactic acid (PLA) even though their decomposition releases acidic by-products, which cause a localized lowering of the bodies pH.[1] Due to a sudden pH-drop inflammatory reactions could appear and lead to a total tissue destruction in the worst case.[2] In order to prevent this undesired reaction in the patients body, new biodegradable PLA materials with a self-regulating pH-degradation behaviour are required. In previous investigations, additives like carbonated calcium phosphates were incorporated into fibres in order to keep the pH during the degradation process at the implant region constant on a physiological level.[3] For a good buffering performance high amounts of incorporated additives are needed, but a sufficient saturation could not be realized, because of instabilities during the spinning process.[4] In this work the pH-regulated degradation should be achieved by incorporating stimuli-responsive microgels with amine functionalities into electrospun PLA-fibres. N-Vinylcaprolactam is used to achieve temperature responsive behaviour and 1-Vinylimidazole is added as a comonomer to introduce pH-responsive properties and to capture free protons with its amine functionality during the PLA degradation.[5] Those microgels are synthesized by precipitation polymerization and the insertion of a biodegradable crosslinker leads to the formation of monodisperse particles. The content of comonomer and crosslinker were varied to optimize the synthesis. In order to incorporate the most suitable microgels into the PLA-fibres, the spinning process was optimized as well. For this purpose, the influence of different organic solvents, molecular weights of PLA as well as the ratio of PLA to microgel have been investigated with the aim to obtain a homogeneous morphology with evenly spread microgels on the PLA-fibres surface. [1] F. W. Cordewener, M. F. van Geffen, C. A. P. Joiasse, J. P. Schmitz, R. R. M. Bos, F. R. Rozema, A. J. Pennings, Biomaterials 2000, 21, 2433-2442. [2] A. Weiler, H. Helling, U. Kirch, T. Zirbes, K. E. Rehm, J. Bone. Joint. Surg. 1996, 78 B, 369-376. [3] C. Schiller, M. Epple, Biomaterials 2003, 24, 2037–2043. [4] P. Schuster, Dissertation: Schmelzgesponnene Polyglykolid-Fasern mit pH-optimiertem Abbauverhalten 2014. [5] K. Fehér, T. Romstadt, C. A. Böhm, M. Kolkenbrock, M. F. Blau, J. Kuehlwetter, A. C. Molano Lopez, A. Pich, J. Hannen, L. Bürgermeister, N. Schaaps, F. Vogt, T. Gries, S. Jockenhövel, BioNanoMat 2015, 16, 259–264. Presentation mode Oral presentation

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Abstract ID 7 Title Self-diagnostic composites Author(s) Prof Enrico Dalcanale1 C P

C: Corresponding author P: Presenting author Affiliation(s) 1 Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma Content The possibility to detect fractures in polymers and composites at the very early stage is of paramount importance for in situ monitoring of mechanical stress and fatigue in structural polymeric materials. So far, most of the activity has been concentrated on mechanochromic thermoplastics, dye-containing polymeric materials that change their color upon mechanical solicitations.[1] Mechanoresponsive materials have been mainly realized by directly linking dyes into the polymer chains of elastomeric or on glassy crosslinked polymers. More recently a different damage-reporting strategy has been introduced, using aggregation-induced emission of fluorophores confined in core-shell microcapsules.[2] An alternative way to access self-diagnostic materials is to introduce supramolecular components where the stress-induced breaking of weak, reversible bonds results in an optical response. In this way, a precise detection of flaws at their initial stage is attainable, enabling an early assessment of the degradation. By also considering that in applications the acting stress state has often a multiaxial nature, the possibility to detect defects at their very first appearance provides a fundamental tool for the subsequent crack growth prediction. Along this line, the use of host-guest complexes as reporting agents for strain detection in silicon elastomers has been very recently proposed by us, using cavitands as hosts and N-methyl pyridinium derivatives as guests.[3] The supramolecular cross-linking complex provides fluorescence response upon dissociation induced by strain. The required amount of the reporting complex is so small (10-6 mol kg- 1) that the mechanical and optical characteristics of the matrix are completely preserved. Epoxy resins and their carbon fiber composites have been selected in view of their technological relevance as light weight replacements of aluminum and steel alloys as structural elements. Here we report the introduction of different host-guest complexes as weak cross-linking agents in Carbon Fiber Reinforced Composites the create selfdiagnostic structural composites in which the turn on fluorescence is observed under fatigue stress, well before the formation of the microcracks in the material. [1] Ciardelli, F., Ruggeri, G., Pucci, A. Dye-containing polymers: methods for preparation of mechanochromic materials, Chem. Soc. Rev. 2013, 42, 857. [2] Moore, J. S. et al. A robust damage-reporting strategy for polymeric materials enabled by aggregation-induced emission, ACS Cent. Sci. 2016, 2, 598. [3] Dalcanale, E. et al. Strain field self-diagnostic PDMS elastomers, Chem. Mater. 2017, 29, 7450.


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Abstract ID 61 Title Solid-state modification to prepare cross-linked polyamides with significant network dynamics Author(s) Dr. Han Goossens1 C P / Dr. Ramon Groote1 C: Corresponding author P: Presenting author Affiliation(s) 1 SABIC, Technology & Innovation Content In this work, cross-linked polyamide resins were prepared using solid-state modification (SSM). Polyamide-6 (PA-6) was cross-linked by incorporation of 10 or 20 mole% of a trifunctional ammonium salt at a SSM temperature of 200 °C (well below the melting temperature of PA-6). Successful incorporation of the cross-linker was achieved with and without an additional transamidation catalyst, provided that the corresponding ammonium salt was used in SSM. Cross-linking of these resins beyond their gel point was confirmed by DMTA measurements; furthermore, after SSM, these polymers were insoluble in good solvents for PA-6. Surprisingly however, test specimen of these covalently cross-linked PA networks could be welded and re-shaped at higher temperatures (~250 °C). As such, these cross-linked PA networks possessed properties that resemble those of vitrimers, a new class of permanently cross-linked polymer networks with network dynamics due to bond exchange reactions. It was found that both cross-linker exchange by transamidation reactions as well as chain slippage and reptation in less densely or non-cross-linked parts of the network contributed to the overall stress relaxation of these materials. Presentation mode Oral presentation

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Abstract ID 20 Title Smart stimuli-responsive liquid crystal polymer coatings for smart windows and sensors Author(s) Dr Nadia Grossiord1 C P / Ir. Ellen van Heeswijk2 / Dr Theo Hoeks1 / Dr André van Zyl1 / Prof. Albert Schenning2 C: Corresponding author P: Presenting author Affiliation(s) 1 SABIC 2 Eindhoven University of Technology Content Modifications aimed at adding stimulus-triggered functionality to surfaces have enabled many new advances, such as self-cleaning, self-replenishing, self-healing, thermal regulation, energy scavenging and anti-(bio)fouling materials. Nature appears to be an inexhaustible source of inspiration as many biological species display remarkable surface structures and chemistries, providing extraordinary properties. Some of the most famous examples of such surfaces are the super-hydrophobic lotus leaves and the water-repellent butterfly wings, the hydrodynamic drag-reducing shark skin, the super-adhesive gecko foot, the hooking device structure of the galium aparins fruits (which led to the invention of Velcro® brand hook and loop fasteners, Velcro Industries B.V.) as well as the reflecting liquid-crystal-based structures of the exoskeleton of the brilliant green beetle. In particular, one way to tune surface reflection of man-made surfaces relies on the use of (helix-shaped) cholesteric liquid crystal polymers (LCPs). The latter combine the stimuli-responsiveness of liquid crystals with the processability of macromolecules, yet they can be used as coatings. LCP coatings can undergo structural changes when light or a thermal, electric, chemical, mechanical or magnetic stimulus is applied. These microscopic changes can significantly modify the macroscopic properties of the surface such as the reflection band (e.g., color) or roughness. In particular, when (helix-shaped) cholesteric LCPs are oriented perpendicularly to a substrate, periodic changes of the refractive index due to the LC orientation change result in the creation of parallel planes of which the properties are described by Bragg’s law. In this contribution, the development and characterization of stimulus-responsive, flexible coatings made of cholesteric LCPs on a plastic substrate will be presented. In particular, we report a two-step, roll-to-roll compatible method for generating flexible LCP coatings durably bound to any plastic substrate. This procedure does not require surface pre-activation, post-polymerization purification steps, or controlled atmosphere. Additionally, LC alignment within the coating is controlled without use of any additive or alignment layer. This way, we were able to produce several types of responsive coatings: (i) flexible (printed) chemical sensors which can shift reflection band and therefore color when in contact with some specific solvents. In this way, they may potentially be tailored to detect specific markers in bodily fluids. (ii) flexible, temperature-responsive infra-red reflectors: these transparent coatings selectively reflected a large band of infra-red radiations at higher temperatures, and also enabled the infra-red radiations to pass through at lower temperatures. Potential applications for this technology include building heat management and smart windows. The development and characterization of flexible, photonic LC polymer coatings on plastic substrates will be discussed in this talk, as well as design rules to ensure fast switching responses and good mechanical properties. Presentation mode Oral presentation

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Abstract ID 175 Title Antibacterial biocompatible electrospun nanofibers based on PCL and erythromycine functionalized halloysite nanotubes Author(s) Ass. Prof. Viera Khunova1 C P / Ass. Prof. Petra Olejnikova1 / Dr. Zdenko Spitalsky2 / Ing. Maria Kovacova3 / Ass. Prof. Dusan Berkes1 / Dr. Kajal Ghosal4 C: Corresponding author P: Presenting author Affiliation(s) 1 Faculty of Chemical and Food Technology, Slovak University of Technology 2 Polymer Institute, Slovak Academy of Science 3 Polymer Institute, Slovak Academy of Sciences 4 Department of Pharmaceutics, Dr. B. C. Roy College of Pharmacy and AHS, Durgapur, India Content Halloysite nanotubes (HNTs) are naturally occurring two-layered aluminosilicate clays with chemical structure Al2Si2O5(OH)4·2H2O. For potential biomedical application, it is very important that unlike plate silicates HNTs can be used as a low-cost nanoscale container for encapsulation of a wide variety of substances including drugs, enzymes, and DNA. A remarkable feature of HNTs is the different surface chemistry at the inner (alumina) and outer (silica) sides of the tubes which enable selective modification of alumina and silica sides. A further important property essential for application in medicine is that HNT exhibits a high level of biocompatibility and are not toxic for the cells (1). Erythromycin inhibits bacterial cells by binding on the 50S ribosomal subunit, preventing the protein synthesis. In addition, erythromycin is clinically used in dermatology as a very effective topical antibiotic drug in the therapy of skin bacterial disease. This study explores HNTs functionalised with Erythromycin (HNTs/Eryth) as a model antibacterial active compound that has a wide range of antibacterial activity on both Gram-positive and Gram-negative bacteria. The antibacterial activity was evaluated as a sterile zone of inhibition around the biodegradable electrospun polycaprolactone (PCL) nanofibres containing 6.6% wt HNTs/Eryth. It was found that studied PCL/HNTs/Eryth nanofibres exhibit outstanding antibacterial properties and result in inhibition of both, Gram-negative (Escherichia coli) as well as Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis) bacteria. The PCL/HNTs/Eryth with strong antibacterial effect and good biocompatibility as well as cost-effective production have a great potential to take important place as new biomedical material. Acknowledgment This research was supported by the Slovak Research and Development Agency under the contract No APVV-17-0078 and by the National Scholarship Programme of The Slovak Republic (Kajal Ghosal). [1] Švachová, V., Khunová, V., Pavliňák, D., Fohlerová, Z., Vojtová, L., Polymer Engineering and Science, 2017, 57(6), pp. 506-512, doi: 10.1002/pen.24512 Presentation mode Poster presentation

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Abstract ID 51 Title Developing soft multiphase polypropylene copolymers for medical packaging: From structure to applications Author(s) Katja Klimke1 C P / Elena Pomakhina1 / Martina Sandholzer1 / Andreas Albrecht1 / Markus Gahleitner1 C: Corresponding author P: Presenting author Affiliation(s) 1 Borealis Polyolefine GmbH, Innovation Headquarters Linz, Austria Content In medical packaging applications, plasticised PVC is still a widely used material despite concerns about the long-term effects of certain plasticisers. In order for polyolefins to work in this sector, good transparency and softness combined with acceptable heat resistance are the most important requirements. Applications like infusion pouches or blow-fill-seal bottles have been demonstrated successfully with advanced random-heterophasic PP copolymers (RAHECOs) from a complex multistage production process. In order to optimise the material design, understanding the structure-property relationships of the obtained materials is a key element. Pilot-scale development of the respective compositions was accompanied by preparative fractionation, followed by fraction analysis via nuclear magnetic resonance (NMR) and other techniques. The findings of this study, correlations between the bulk structure and the application performance of the RAHECOs, alias SoftPP products, is presented in this work. Presentation mode Oral presentation

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Abstract ID 131 Title Anti-fouling zwitterionic coatings through surface-initiated atom transfer radical polymerization at supramolecular biomaterial surfaces Author(s) Ms. Muhabbat Komil1 2

P C / Mr. Bastiaan Ippel1 2 / Mr. Paul Bartels1,2 / dr. Maarten Smulders3 / Prof. dr. dr. Patricia Dankers1 2 C: Corresponding author P: Presenting author Affiliation(s) 1 Institute for Complex Molecular Systems, Eindhoven University of Technology 2 Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology 3 Laboratory of Organic Chemistry, Wageningen University Content Anti-fouling coatings on biomaterials act as cell and protein resistant surfaces. By decreasing immunological responses, the lifetime of a biomaterial is prolonged to carry out its function. One of the many possible ways to obtain anti-fouling material coatings is surface modification with zwitterionic polymers. The zwitterionic layer prevents adhesion by forming a hydration layer due to electrostatic hydrogen bonds between the water molecules and the charges of the zwitterion. By applying surface-initiated (SI) controlled radical polymerization, control over brush thickness, composition and architecture is achieved. This work demonstrates the grafting from approach of sulfobetaine methacrylate on quadruple hydrogen bonding ureidopyrimidinone (UPy) functional supramolecular biomaterials. Initially, UPy functional macroinitiator was synthesized and successfully incorporated into the supramolecular UPy-films at different concentration. Zwitterionic sulfobetaine methacrylate was grafted on the supramolecular film surfaces by SI atom transfer radical polymerization. The polymerization was carried out for various time points to evaluate the effect the polymer brush thickness on the anti-fouling performance. Post-grafting the surfaces increased the hydrophilicity, which was determined by contact angle goniometer. X-ray photoelectron spectroscopy revealed the presence of sulfur and quaternary ammonium atoms of the sulfobetaine moiety post-grafting. With atomic force microscopy, post grafting changes on the surface morphology of the biomaterial were visualized. Furthermore, in vitro cell culture experiments demonstrated a promising anti fouling performance, as polymer grafted biomaterials showed significant reduction in cellular adhesion on the biomaterial surfaces. This work expands our functional supramolecular biomaterial library with zwitterionic polymers, and can be easily applied to a variety of hydrophilic (meth-)acrylate and (meth-)acrylamide monomers. The next step towards anti-fouling biomaterials is surface modification of electrospun scaffolds, which can be used as potential synthetic biomaterials, amongst many others, with polymeric coatings. Additionally, we are currently working on polymerization of various hydrophilic monomers in solution with the UPy functional macroinitiator. Hereby, versatile pH-, temperature-responsive and bioactive polymers with UPy-functionality can be combined with our existing library of UPy-functional polymers, to achieve a wide range of functional supramolecular biomaterials, ranging from solid materials to hydrogels. Presentation mode Oral presentation

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Abstract ID 10 Title Polyolefin foam materials in medical, healthcare and injury-preventing applications; the scientific link between polymer building blocks and the performance of their foamed ‘species’ Author(s) Ing. John Krist1 2

C P C: Corresponding author P: Presenting author Affiliation(s) 1 Lightweight Materials 2 SABIC Foam Innovation Center Content Polyolefin foams have a wide field of applications in medical, healthcare and injury-preventing applications. Relevant applications include medical tape, cervical braces, medical packaging, healthcare-related footwear and complete body protection gear. Water resistance, moldable, soft, lightweight, cushioning or hypo-allergenic properties of the finished foamed products are some of the drivers that are considered by the industry when choosing polyolefin foams. The presentation will make a deep-dive into the basic polyolefin building blocks used to produce these foams, with a specific focus on Polyolefin Elastomers (POE), Polyolefin plastomers (POP), LDPE, PP-UMS and their blends. Material and/or molecular properties that define the required properties, such as strain hardening to provide physical foamability, are examined. Further intermediate processing steps are reviewed to obtain final product properties and shapes: • Direct physical foaming, generating ultra lightweight • Crosslinking to generate higher temperature resistance, resilience and thermoform-ability • Particle foams to create shapes by molding Finally, several analyses are executed to demonstrate how the final properties of the foams, both mechanical, thermal and morphological, are linked to the building blocks and their blends. Presentation mode Oral presentation & poster presentation

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Abstract ID 105 Title Contact-killing of Gram Positive and Gram Negative Bacteria on Various Substrates Covered with an Immobilized Hyperbranched Coating Author(s) Prof.dr. Ton Loontjens1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 University of Groningen Content Biomaterial based implants and devices are widely applied to restore human function and shape once beyond natural repair. However, biomedical material related infections is still a major drawback of implants. Antibacterial coatings may offer a technology to prevent infections on devices. Hyperbranched coatings (HBC) were immobilized via a novel coupling agent able to react with a substrate and the HBC. The next applied polyethyeleneimine controlled the crosslink density of the coatings and the quaternized amines were biocidal. High killing properties for Gram-positive and Gram-negative bacteria on contact were obtained. Presentation mode Oral presentation

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Abstract ID 157 Title Solutions to prevent physical and chemical changes of polypropylenes upon sterilization with gamma and ebeam irradiation Author(s) Dr Sarah van Mierloo1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 SABIC, Geleen, The Netherlands Content Although polypropylene is increasingly used for healthcare applications (drug delivery, labware, medical devices, medical diagnostics and healthcare packaging), it is known that high energy sterilization via gamma or e-beam irradiation generates radicals, leading to degradation of the polymer (chain scission playing a dominant role). Mechanical (embrittlement), rheological (reduced melt viscosity) and optical (yellowing) properties are most affected. During the irradiation procedure, polymer viscosity decreases and discoloration (mainly yellowing resulting from antioxidant conversion products) is occurring. Then, during post-irradiation storage, the polymer keeps degrading (enhanced thermo-oxidation), leading to increased brittleness and further yellowing, limiting shelf life of disposable articles, which makes long term studies necessary. The aim of this research work was to find suitable solutions for these undesired side effects of radiation sterilization in polypropylene healthcare applications. The influence of mobilizing agents, clarifying agents and stabilizers was studied. One objective was to prevent polymer discoloration, the other to maintain acceptable mechanical properties during and after post-irradiation storage. Appearance (color, haze), mechanical (tensile modulus, tensile (yield) strength and impact strength), rheological (MFI) and GPC measurements were applied to investigate the irradiation induced changes in polypropylene injection moulded plaques, including post-irradiation behaviour (different storage times). Surface chemical changes under influence of irradiation and subsequent storage were also studied using ATR-FTIR spectroscopy. Finally, oven ageing experiments were performed to investigate the effect of post-irradiation storage. Gamma irradiation (35 kGy and 55 kGy) and e-beam irradiation (40 kGy) were chosen for this study. Presentation mode Oral presentation

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Abstract ID 135 Title Healthcare Grade Polymer Data Validation to Enable Innovative Application Development Author(s) Mr Subhransu Sekhar Mohapatra1 C / Dr Prasad Dasappa1

/ Mr Nitesh Kumar Shet1 / Mr MSenthil Murugan1

/ Mr Richard Peters2

/ Mr L Chandrasekhar3 / Mr G Sadasivam3 / Dr. Syed Muhammad Kashif1

P C: Corresponding author P: Presenting author Affiliation(s) 1 SABIC Research & Technology Private Ltd 2 SABIC 3 SABIC Research & Technology Pvt Ltd Content Future healthcare needs demand innovative application developments that can be achieved by optimizing material performance, design development and cutting edge manufacturing processes. Prior to investing in tooling and production equipment, computer modeling is often used to create prototype designs. The availability of accurate material engineering data in this phase can help shorten the application development cycle. This paper will explain the process and importance of validated, comprehensive material data for healthcare-grade polymers to aid in a “first-time right” development approach for applications that require mechanical loading evaluation. The material data validation process starts with the selection of a representative part and the identification of the appropriate mechanical loadings representing its field application. Physical testing is performed on the validation parts molded with various polymer types, fiber composition, and filler distribution and the results are captured. In parallel, Computer Aided Engineering (CAE) models are developed at various levels of complexity, starting from the most basic single element level to the part validation level. Performance evaluations at these different levels of complexity are predicted using the polymer characterization data. The comparison results show excellent correlations between the virtual model predictions (CAE) of mechanical performance data and the physical test results. This helps to ensure a high level of confidence that the application developers can rely on while using the material data for virtual development processes. Presentation mode Oral presentation

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Abstract ID 129 Title Effect of transcrystalline layer against water absorption of bio-composites Author(s) Mr Alexandros Prapavesis1 C P / Prof. Dr. Ir. Aart Willem van Vuure1 C: Corresponding author P: Presenting author Affiliation(s) 1 Department of Materials Engineering, KU Leuven, Kasteelpark Arenberg 44, 3001 Heverlee, Belgium Content Materials selection has an important role in optimizing the relationship between properties and cost of prosthetics, particularly for third world countries. Natural fibres as a reinforcement could possibly have a potential to replace part of the traditional materials used in artificial limps [1] due to their good specific mechanical properties that often come at a moderate cost, good vibration damping, non-toxicity and natural aesthetic appearance. However, despite their potential the widespread use of natural fibre reinforced composites is limited by the hydrophilic nature of the fibres. When exposed to humid environments, natural fibres inevitably interact with the present water, where the absorbed moisture not only affects the internal structure of the fibre but also damages the fibre-matrix interface leading to a dramatic decrease in stiffness. One way of addressing this problem is through the development of protection methods for the fibres making them more water insensitive. It is well established that the degree and morphology of crystallinity in a polymer is of pivotal importance to the mechanical and barrier properties of the final product. Crystallites can act as obstacles to the diffusion path of water molecules because of the well packed structure of crystals, which essentially makes them behave as inert impermeable fillers in an amorphous matrix [2]. Additionally, foreign surfaces in a polymer melt (e.g. fiber surface) can act as nucleation agent promoting heterogeneous nucleation along the fibre surface resulting in the formation of a columnar layer known as transcrystalline (TC) layer [3]. In this study, we investigate the feasibility of using transcrystalline layers as an effective protection method against water absorption of flax/MAPP and flax/MA-HDPE composites. Both amorphous and annealed composites were manufactured by compression molding. Differential scanning calorimetry (DSC) and polarized optical microscopy was used to identify the TC layer. The effect of transcrystallinity on the mechanical properties was studied by 3-point bending, before and after hydrothermal exposure at 80% relative humidity. [1] D. Chandramohan and A. J. P. Kumar, “Fibre Reinforced Composites : a Promising Material for Artificial Limp,” Data-Enabled Discov. Appl., pp. 1–9, 2017. [2] Z. Duan and N. L. Thomas, “Water vapour permeability of poly(lactic acid): Crystallinity and the tortuous path model,” J. Appl. Phys., vol. 115, no. 6, 2014. [3] N. E. Zafeiropoulos, C. A. Baillie, and F. L. Matthews, “Study of transcrystallinity and its effect on the interface in flax fibre reinforced composite materials,” Compos. Part A Appl. Sci. Manuf., vol. 32, no. 3–4, pp. 525–543, 2001.


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Abstract ID 101 Title A story of romance: antifouling, functional zwitterionic polymer brushes on flat surfaces and beads Author(s) Dr. Maarten Smulders1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 Wageningen University, Laboratory of Organic Chemistry Content In order to enhance the sensitivity and selectivity of surface-based (bio)sensors, it is of crucial importance to diminish background signals that arise from the non-specific binding of biomolecules; a process called biofouling. Zwitterionic polymer brushes have been shown to be excellent antifouling materials.[1] However, for sensing purposes, antifouling does no suffice, but needs to be combined with the possibility to efficiently modify the brush with recognition units. So far this has only been achieved at the expense of either antifouling properties or binding capacity. In this contribution, firstly, a conceptually new approach is presented that relies on integrating both characteristics into a single, tailor-made monomer: a novel sulfobetaine-based zwitterionic monomer equipped with a clickable azide moiety.[2] Ultimately a surfaces is created that can specifically bind its target analyte, but repels all other bio(molecules) present in the medium. Micron- and nano-sized particles are extensively used in various biomedical applications. However, their performance is often also drastically hampered by the non-specific adsorption of biomolecules, which can cause false-positive and false-negative outcomes in diagnostic tests. Although antifouling coatings have been extensively studied on flat surfaces,[1] their use on micro- and nanoparticles remains largely unexplored, despite the widespread experimental (specifically, clinical) uncertainties that arise because of biofouling. In this contribution, the preparation of magnetic micron-sized beads coated with zwitterionic sulfobetaine polymer brushes that display strong antifouling characteristics is presented.[3] These coated beads can then be equipped with recognition elements of choice, to enable the specific binding of target molecules (Figure 1). A proof of principle is presented with biotin-functionalized beads that are able to specifically bind fluorescently labelled streptavidin from a complex mixture of serum proteins. Also, the versatility of the method is shown by demonstrating that it is possible to functionalize the beads with mannose moieties to specifically bind the carbohydrate-binding protein concanavalin A. Flow cytometry was used to show that thus-modified beads only bind specifically targeted proteins, with minimal/near-zero nonspecific protein adsorption. These antifouling zwitterionic polymer-coated beads, therefore, provide a significant advancement for the many bead-based diagnostic and other biosensing applications that require stringent antifouling conditions. In addition, using flow cytometry as read-out system, these beads offer a platform for the systematic comparison of zwitterionic and non-zwitterionic antifouling polymer brushes.[4] [1] J. Baggerman, M. M. J. Smulders and H. Zuilhof, Langmuir 2019, 35, 1072. [2] S. C. Lange, E. van Andel, M. M. J. Smulders, H. Zuilhof, Langmuir 2016, 32, 10199. [2] E. van Andel, I. de Bus, E. J. Tijhaar, M. M. J. Smulders, H. F. J. Savelkoul and H. Zuilhof, ACS Appl. Mater. Interfaces 2017, 9, 38211. [3] E. van Andel, S. C. Lange, S. P. Pujari, E. J. Tijhaar, M. M. J. Smulders, H. F. J. Savelkoul, H. Zuilhof, Langmuir 2019, 35, 1181. Presentation mode Oral presentation

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Abstract ID 86 Title Virtual chemistry lab: Designing improved materials using state-of-the-art computational chemistry simulations Author(s) Dr. Teun Sweere1 C P / Dr. Bhaskar Patham2 / Vijayakumar Sugur2 / Dr. Jan-Willem Handgraaf1 / Dr. Maria Soliman3 C: Corresponding author P: Presenting author Affiliation(s) 1 Culgi B.V., Leiden, The Netherlands 2 SABIC Technology & Innovation, SABIC Technology Center – Bangalore, India 3 SABIC Technology & Innovation, SABIC Technology Center – Geleen, The Netherlands Content Modeling and simulation are increasingly becoming a key complement to experiments in the field of material and formulation development. On the one hand, the enhanced leverage of information-technology for integration and analysis of vast amounts of legacy experimental data creates the possibility to identify unique materials solutions for challenging applications. On the other hand, the maturity of simulation approaches, ranging from quantum to continuum, combined with exponential growth of computational capacity, allows us to simulate material behavior with unprecedented amounts of detail. Development of new polymeric materials and formulations addressing a multitude of challenging demands – ranging from barrier, morphology, rheology, processability, thermo-mechanical, electromagnetic and optical or a combination of these – requires access to a vast amount of fundamental material properties. Experimental measurement of all the properties for each material candidate is an impractical proposition. Developing new materials with tailored properties then becomes an even more formidable task to take up on a purely empirical basis. In this context, we are employing multi-scale computational chemistry approaches as a practical and cost-effective way of complementing experimental measurements to (1) first estimate these fundamental material parameters of relevance to a property and (2) then to virtually iterate upon chemistries, formulations, and / or microstructures that offer the best performance for a chosen application. The multi-scale approaches – involving a combination of quantum chemistry, coarse-grained simulations and molecular dynamics simulation using atomistic renditions as well as field-based near-continuum approaches – are especially relevant for designing novel polymeric materials in an efficient way. The use of purely atomistic approaches with polymeric materials can result in long and computationally expensive simulations, often necessitating the use of simplifications to avoid the computational overhead. By employing multi-scale simulation schemes, we have developed and implemented several novel approaches involving coarse-grained simulations that allow rendition of more realistic polymers while significantly bringing down the associated computational costs and turnaround times. In this talk, we demonstrate these approaches using two case-studies. The first case study addresses the assessment of barrier and permeability properties of small gaseous and higher-molecular-weight organic permeants through polymers with olefinic as well as aromatic backbones. The second case study deals with the estimation of the morphology of block and graft copolymers relevant for a variety of applications. Presentation mode Oral presentation & poster presentation

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Abstract ID 132 Title Printing of Microgel Arrays for Regulation of Cell Motility and Adhesion Author(s) M.Sc Alexander Töpel1 2

P C / Prof Andrij Pich1 2 / Dr Antonio Sechi3

C: Corresponding author P: Presenting author Affiliation(s) 1 Institute of Technical and Macromolecular Chemistry, RWTH Aachen University 2 DWI Leibniz Institute for Interactive Materials 3 Institute of Biomedical Engineering, Dept. of Cell Biology, Uniklinik RWTH Aachen Content Microgels are three dimensional cross-linked polymer colloids which can react by a change of size onto outer stimuli. These stimuli can be pH, salt, temperature or light. Due to their swelling ability they can contain upto 90% water. This makes them an interesting polymeric material for interaction with biological systems. Topology and surface chemistry are powerful tools to affect cell adhesion and migration. We focused on use of microgels as building blocks for the decoration of biointerfaces. We developed recently a new technique that allows printing microgels on solid substrates. By using wrinkled PDMS templates we successfully printed stimuli-responsive poly(N Isopropylacrylamide) (pNIPAm) microgels in form of colloidal arrays on glass supports. By using low-pressure Argon plasma the microgels were chemically grafted onto the glass substrates. This process lead to highly stable microgel arrays in cell culture media. We could identify the influencing factors on the printing process and were able to print microgels of different size and cross-linking density. We demonstrated that our surface-grafted microgel arrays could serve as novel substrates for the analysis of cell adhesion and migration. Microgel arrays influenced size, speed and dynamics of focal adhesions as well as cell motility forcing cells to move along highly directional trajectories. Modulation of microgel state, spacing or cross-linking density served as an effective tool for regulation of cell motility. [1] S. Hiltl, M. Schürings, A. Balaceanu, V. Mayorga, C. Liedel, A. Pich, A. Böker, Soft Matter 2011, 7, 8231-8238. [2] A. S. Sechi, S. Ullmann, J. M. G. Freitas, R. P. Takehara, P. Wünnemann, A. Töpel, R. Schröder, M. Zenke, A. Böker, G. Aydin, S. Rütten, Andrij Pich, Adv Mater. Interf. 2016, DOI 10.1002/admi.201600455 . Presentation mode Oral presentation

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Abstract ID 152

Title Model Silicone Hydrogels: Morphology and Oxygen Permeability Author(s) Dr Meredith Wiseman1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 DSM Content Silicone hydrogel contact lenses are radically cured amphiphilic networks containing hydrophilic and siloxane moieties that must allow for permeability of oxygen and ions while remaining well mixed and homogeneous enough at large length scales to be transparent. We report on the morphology of a model silicone hydrogel system, rationalizing the macroscopic transport behavior in terms of nanoscale phase separation and chain mobility. Presentation mode Oral presentation

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Abstract ID 182

Title Advanced In-Operando Synchrotron-Based Tools for Studies of Microstructure, Thermal Transitions and Mechanical Behavior of Polymers Author(s) Prof Dimitri Ivanov 1 C P C: Corresponding author P: Presenting author Affiliation(s) 1 CNRS (France) Content The design of new polymer materials often requires a detailed knowledge of their structure and physical properties such as phase transitions (e.g., melting-reorganization) and mechanical behavior (e.g., mechanisms of deformation and rupture). In the present talk, we will dwell on the development of in-operando synchrotron-based techniques allowing to perform: 1) Simultaneous structural and mechanical experiments with resolution of the X-ray setup extending into the micrometer range; 2) High-resolution scanning with nanofocused X-ray beams with the beam footprint in the submicron range; 3) Combination of fast scanning chip calorimetry (FSC) with fast X-ray scattering employing single-photon-counting last-generation detectors. The setup allows performing continuous synchronous acquisition of the thermal and 2D X-ray data with time exposure on the order of one millisecond. The first topic will be exemplified for the case of newly developed super-soft and hyperelastic elastomers, in which the side chains grafted onto network strands act as both entanglement diluents and mechanical property regulators.[1] Precise and independent tuning of side-chain degree of polymerization and grafting density yields materials with Young’s moduli down to ~10^2 Pa and elongation-at-break up to 10.[2] These physically crosslinked bottlebrush networks replicate the modulus of polymeric gels and biological tissues and recreate tissue’s extreme strain-stiffening behavior.[2-3] The second and third topics will be illustrated for studies of thermal behavior of commodity semicrystalline polymers. In particular, the setup [4] allowed monitoring the early stages of crystallization of HDPE in order to evaluate the morphology and exact supercooling at the crystal growth front. To this end, the lattice parameters of the crystals, which are younger than 5 milliseconds were measured during fast cooling ramps at heating rates faster than 1000 K/s. The use of such rates allows bypassing the recrystallization processes on heating and cooling and facilitates in-depth analysis of the thermal behavior. By using heating and cooling rates much higher than the rates of recrystallization, the structural transformation corresponding to each of the observed thermal events can be extracted from X-ray data analyzed in detail. References 1. W.F.M. Daniel, et al. Nature Materials 15, 183 (2016); M. Vatankhah-Varnosfaderani, et al. Nature 549, 497 (2017). 2. M. Vatankhah-Varnosfaderani, et al. Science 359, 1509 (2018) 3. Charles Clair, et al., ACS MacroLetters (2019) 8, 530–534. 4. Rosenthal, et al. Journal of Synchrotron Radiation, 21 223 (2014). Presentation mode Oral presentation

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Abstract ID

Title Controlled structuring of polymers by processing – science, technology and medical technology applications Author(s) P.D. Coates1 p c / P. Caton-Rose1 / B.R. Whiteside1 / D. Vgenopoulos1 / G. Thompson1 / J. Sweeney1 / K. Nair1 / M. Babenko1 / C. Tuinea-Bobe1 / P.J. Hine2

C: Corresponding author P: Presenting author Affiliation(s) 1 University of Bradford 2 University of Leeds Content It is increasingly recognised that properties of polymers and polymer composites depend on the structure imparted during processing, which we term ‘process structuring’. Two major areas of controlled process structuring for enhanced polymer properties will be covered, namely solid phase orientation and ultra-precision micromoulding. These can involve routes to specific ‘property gradient’ and ‘property distribution’ products. Solid phase orientation processing at temperatures between Tg and the melting point provides a most striking example of process structuring, in terms of the magnitude of property changes which can be achieved—e.g., several hundred percent enhancements in physical properties. Molecular orientations and large scale effective morphological reorganisations achieved by drawing or other forming processes can be locked into the final product, which remain stable in final products. The products can be used for significant load bearing applications, or orientation may be intentionally recoverable in a controlled manner, for ‘shape memory’ products. Remarkable cost-effective improvements in properties can consequently be achieved in many polymers and polymer composites by solid phase orientation processing, with applications including medical technology (e.g. tissue fixations, stents, drug eluting implants), construction (the spin-out at www.eovationsllc.com ), high performance pipes, and personal products. Die drawing is a unique technology where solid polymers are drawn through a die or over mandrels, to achieve controlled enhancement of physical properties for many polymers, including selected axial or biaxial orientation distributions, at commercially viable production rates and at a range of length scales, e.g. 100 micron wall thickness tubes for bioresorbable stents, to tens of millimetres thick sections for structural applications, in either batch or continuous mode processing. Our fundamental studies of polymer deformation, include necking and structural evolution analyses, and FEA of processing, including current collaborations with leading Chinese research groups, in Sichuan and Changchun, for structure developments, and the potential for using oriented polymers in medical technology applications. Our ultra-precision micro moulding area involves controlled process-structuring of polymers, including control of morphologies e.g. for shape memory products, blends, electrically conducting materials, and geometries, e.g. surface feature control. We employ and develop extensive in-process measurements. Some commercialised or developing products, particularly in the medical devices area, are discussed. Presentation mode Oral presentation

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