final conference 19.6 - sunpapsunpap.vtt.fi/pdf/final_conference/5_sunpap_missoum_2012.pdffinal...

AKD nano-emulsions: Innovative technique to increase

the solid content of NFC suspensions

Final Conference 19.6.2012

Karim Missoum, Mohamed Naceur Belgacem, Julien Bras*

*[email protected]

OUTLINES

AKD nano-emulsions : Innovative technique to increase the solid content of NFC

suspensions

2

I. NFC and Nano-emulsions: Introduction

II. Materials & Methods

III. Results & Discussions : Efficiency of grafting

IV. Conclusions & Perspectives

• Agglomeration when dried

• Difficult to re-disperse

• Poor compatibility with

hydrophobic polymers

From Fibers to Nanocelluloses

3

Impossible to use industrially Coating / extrusion etc…

• Gel at very low concentration

Drawbacks 2 to 10 m².g-1

1% OH accessible

51 m².g-1

3,1% OH accessible

Fiber x10

NFC

Siqueira, Bras et al. (Langmuir 2010)

2% wt

State of art: Chemical modification of NFC

4

• Very few scientific paper available in literature

• Few reactions studied: 3 main kinds of chemical modifications

Adsorption processes Molecules modification Polymer grafting

o Surfactant adsorption Syverud et al., 2011, Xhanari et al., 2011

o Polymer adsorption Aulin et al., 2008

o Silylation Andresen et al., 2006, Johansson et al., 2011

o Carbanilation Siquiera et al., 2010

o Esterification Tingault et al., 2010, Rodionova et al., 2011

Missoum et al., 2012

o Sn(Oct)2-Catalyzed ROP Lönnberg et al., 2011

o Cerium-induced reaction Littunen et al., 2011

NO WATER BASED PROCESSES

5

Proof of concept

- Limit the use of organic solvent

- Development of water based “green

processes”

Emulsion in

aqueous media

Strategy :

Project requirement :

- Limit hydrogen interactions with water by chemical modification

HO OH HO OH

RO OR

RO OR

Classical emulsions

6

Mechanism well-known since 70’s

H2O

H2O

100µm

Alkyl Ketone Dimer (AKD)

Micro vs. Nano-emulsions

More homogeneous coverage of NFC using nano-emulsions

2) AKD nano-emulsions 1) Classical AKD emulsions

7

Cellulose and AKD emulsions

8

• Interactions between AKD and cellulose well known (Linstrom T. et al., 2008)

• Classically used in papermaking industry processes

No papers dealing with grafting using a sizing agent onto NFC in water based media

To

da

y

To

morr

ow

• How to perform a nano-emulsion of AKD ?

• Interactions with NFC ?

Based on electrostatic interactions

9





OUTLINES


suspensions

Preparation of NE

Chemical Reaction

10

* O

OO

OH

OHOH

OH

OH

OH

OO n

Cellulose

* O

O

RO

O

OO

OR

ROOR

RO

Op

NH

O

or H depending on the DSR = CO-NH-(CH2)17-CH3

Cellulose octadecylcarbamate

* O

O

RO

O

OO

OR

ROOR

RO

Op

O

or H depending on the DSR = CO-(CH2)16-CH3

Cellulose stearate

i

ii

+

Modified cellulose

* O

O

R O

O

O O

O R

R O O R

R O

O p

O

R1

R (O=C-R1) or H depending on the DS

R1 (CH2)17CH3

Alkyl Ketone Dimer (AKD)

AKD + CHCl3

Water + surfactant

Mix

Sonification

Evaporation CHCl3

70

C

Tetradecyltrimethylammonium bromide (TTAB)

NFC-CTP NFC-TE/CTP

Procedure

Adsorption phenomena

AKD +

CHCl3 NFCs NE

+

+ +

+ +

+ +

+

+ +

+

+ +

+ +

+ +

+

+ +

-

- -

- -

- -

-

- -

-

- -

- -

- -

-

- -

+ ???

Surface charges of

NE and NFC ?

• NO well defined scientific paper for the determination of surface charge of NFC

• Nano-emulsion = Risk of agglomeration and destabilization (Sarazin et al. 2010)

Literature review

11

NFC-AKD

NFC-CTP

NFC-TE/CTP



III. Results & Discussions


1) Nano-emulsion & NFC

2) Interactions NFC/NE

3) Applications

OUTLINES


suspensions

12

Nano-emulsions

• Influence of dilution & surfactant (pilot) ?

• Spherical modeling ?

• Charge surface ?

+

+

+

+ +

+ +

+

+ +

+

+

+

+


AKD +

CHCl3 NFC NE

+

+ +

+ +

+ +

+

+ +

+

+ +

+ +

+ +

+

+ +

-

- -

- -

-

- -

-

+

13

Nanoemulsion : Fundamental Characterizations

14

• Stability parameters function of time and dilution volume : Checked

• Without Surfactant : Destabilization of the micelles till D = x100

0

100

200

300

400

500

600

700

800

0 50 100 150 200 250

Size

(n

m)

Time (min)

Size vs dilution volume vs timeWITHOUT surfactant

D x 2 D x10 D x 20 D x 40 D x 100 D x 200 D x 400

• Time of dilution:

5min/30min/1h/2h/3h/4h

Pilot condition:

Dilution x40

Time : 4h

Risk of destabilization

15

• Stability parameters function of time and dilution volume : Checked

• With Surfactant : Diameter conserved for high dilution volume

0

50

100

150

200

250

300

350

400

450

0 50 100 150 200 250

Size

(n

m)

Time (min)

Size vs dilution volume vs timeWITH surfactant

D x 2 D x10 D x 20 D x 40 D x 100 D x 200 D x 400

• Time of dilution:

5min/30min/1h/2h/3h/4h

Better to use

surfactant

solution for pilot

scale

Nanoemulsion : Fundamental Characterizations

Fundamental Characterizations

• Control of the size : Checked (range 60 – 160 nm)

Intensity = f (Micelles diameter)

-2

0

2

4

6

8

10

12

14

16

1 10 100 1000 10000

Micelles diameter

Inte

nsi

ty (

%)

AKD/H20 = 10/90 (w/w)

AKD/H20 = 4/96 (w/w)

AKD/H20 = 2.5/97.5 (w/w)

AKD/H20 = 1.5/98.5 (w/w)

AKD/H20 = 0.3/99.7 (w/w)

Ratio

AKD / H2O

Average

(nm)

10 / 90 155

4 / 96 121

2.5 / 97.5 88

1.5 / 98.5 83

0.3 / 99.7 58

Modeled on spherical particles equation 16

17

Validation of theoretical sphere modeling

BUT not adapted for charge measurements

Fundamental Characterizations

FE-SEM environnemental

• Gramm method (NaOH titration) for total charge of NFCs

• New method for characterization of NFC surface charges (polyDADMAC)

• NFC-TE/CTP better (60 times!) than NFC-CTP for the nano-emulsion

adsorption

Charge characterization


AKD +

CHCl3 NFC NE

+

+

+ +

+ +

+ +

+ + -

- -

- -

-

- -

-

+

-

- -

- -

-

- -

-

18

Materials Total Charge

(µeq/g)

Surf. Charge

(µeq/g)

Charges at

surface

NFC-CTP 20.6 5.9 30 %

NFC-TE/CTP 1300 1400 100 %





1) Nano-emulsion


3) Applications

OUTLINES


suspensions

19

NFC and nanoemulsion interactions


AKD +

CHCl3 NFC NE

+

+

+ +

+ +

+ +

+ + -

- -

-

- -

- -

-

+

• What about the phenomenon?

• What about the grafting

• Is it possible to visualize adsorption interactions?

20

NFC-CTP NFC-AKD NFC-TE/CTP NFC-TE-AKD

21


• Water sorption

• NFC-TE/CTP more

hydrophilic than NFC-CTP

• Hydrophobic behavior of

treated NFCs

• Absorption capacity strongly

decreased (with water) after

grafting

• Efficiency of AKD treatment

on NFCs properties

+ 350%

- 80 % - 93 %

NFC-TE/CTP and nano-emulsion interactions

22

• Contact angle and Infra-red measurements

Mean contact angle 0 = 90° for modified NFC

(CHx) stronger and presence of Ester vibration

= 90°

= 73°

Modified NFC-TE/CTP

NFC-TE/CTP

Modified

NFC-TE/CTP

NFC-TE/CTP

NFC/CTP and nanoemulsion interactions

23

• Contact angle and Infra-red measurements

4000 3000 2000 1500 1000 800

cm-1

Reference

1730 cm-1 => (C=O)

Ester function

2850 &2950 cm-1 => (CHx)

Aliphatic chain ok AKD

0

20

40

60

80

100

120

0 5 10 15 20 25 30 35 40 45 50

Conta

ct

angle

(degre

e)

Time (s)

Contact angle measured with water

Initial contact angle 0 = 115°and decrease (due to the porisity of film?)

(CHx) stronger and presence of Ester vibration

• Porosimetry

-1,00

0,00

1,00

2,00

3,00

4,00

5,00

6,00

7,00

8,00

9,00

0,0010,010,1110

dV

/D (

ml/

g/µ

m)

Diameter (µm)

Porosimetry Hg : Volume penetration vs Diameter

Neat NFC Modified NFC NE-AKD

• Pore size Distribution of

neat NFC broader than

modified NFC

• 3 different ranges of pore

size for modified NFC

Pores size

NFC-CTP From 4 to 20 nm

Centered on 7 nm

NFC-AKD 3 to 4 nm

4 to 10 nm

10 to 20 nm


• Similar results for NFC-TE/CTP and NFC-TE-AKD

Scale

24

NFC-CTP

NFC-AKD

25

Environmental FE-SEM : Wet conditions (49.2 % of humidity) NFC + AKD

NFC and nanoemulsion interactions “Nanomaterials” platform in Grenoble-FRANCE (Minatech)

Interest: work under wet conditions (0 to 100% of humidity) limitation of aggregation effect





1) Nano-emulsion


3) Applications

OUTLINES


suspensions

26

Adsorption Filtration Drying

Activation Redispersion

AKD +

CHCl3

NFC

NE

25°C – 4h

Bulk : Paper Post drying

Coating formula

+

+ +

+ +

+ +

+

+ +

+

+ +

+ +

+ +

+

+ +

-

- -

- -

- -

-

- -

-

- -

- -

- -

-

- -

Grafting

Procedure :

27

28

NANO-EMULSIONS : Rheology measurements

5% wt

1E-03

1E-02

1E-01

1E+00

1E+01

1E+02

1E+03

1E+04

1E+05

0 0,02 0,04 0,06 0,08 0,1 0,12 0,14

Concentration

Vis

coci

ty (

Pa.s

)

Influence of modified NFC content on viscosity at different shear rate

= 0.01 s-1 •

= 0.1 s-1 •

= 1 s-1 •

= 100 s-1 •

= 1000 s-1 •

28

29

Coating applications at lab scale

0E+00

1E+00

2E+00

3E+00

4E+00

5E+00

6E+00

7E+00

0 0,01 0,02 0,03 0,04 0,05 0,06 0,07 0,08 0,09 0,1 0,11 0,12 0,13 0,14

Concentration

Vis

coci

ty (

Pa.s

)

Influence of NFC content on viscosity

Unmodified NFC

Increase of solid content for a same viscosity

= 100 s-1 •

Modified NFC

5% - Redispersion 13% - Centrifugation 2.7% - Dilution 0.9% - Dilution

+ 12.8 %

NFC-AKD

NFC-CTP

Scale – up : Formulation

30

0E+00

1E+00

2E+00

3E+00

4E+00

5E+00

6E+00

7E+00

8E+00

0 0,01 0,02 0,03 0,04 0,05 0,06 0,07 0,08 0,09 0,1 0,11 0,12

Concentration

Vis

coci

ty (

Pa.s

)

Influence of NFC content on viscosity

Unmodified NFC

Increase of solid content for a same viscosity: Scale - up

= 100 s-1 •

Modified NFC

+ 3 %

NFC-AKD

NFC-CTP

0,00E+00

5,00E+01

1,00E+02

1,50E+02

2,00E+02

2,50E+02

3,00E+02

Ref CC + Water NFC

0.01 s-1

0,00E+00

5,00E-02

1,00E-01

1,50E-01

2,00E-01

2,50E-01

3,00E-01

3,50E-01

Ref CC + Water NFC

100 s-1

31

COATING COLOR : Rheology measurements

0,00E+00

5,00E+01

1,00E+02

1,50E+02

2,00E+02

2,50E+02

3,00E+02

NFC ModifiedNFC

0.01 s-1

0,00E+00

5,00E-02

1,00E-01

1,50E-01

2,00E-01

2,50E-01

3,00E-01

3,50E-01

NFC ModifiedNFC

100 s-1

0.01 s-1

100 s-1

-84 %

-93 %

31

Ref CC+ water NFC-CTP

Ref CC+ water NFC-CTP NFC-CTP NFC-AKD

OUTLINES


suspensions

32





Conclusions

• Nanoemulsion

- Validation of spherical model of nanoemulsion

- Size of micelles well controlled

- Impact of the surfactant in comparison to dilution volume and time

+

+

+ +

+ +

+ +

+ +

• Nanofibrillated cellulose

- Characterization of the total and surface charge (NFC-CTP & NFC-TE/CTP)

- All charges are at the surface for NFC-TE/CTP ! Better for adsorption -

- -

- - -

- -

-

• Interactions

- Water sorption, IR and contact angle well adapted for characterization

- “Hg” porosimetry shows 3 ranges of pores diameter with AKD treatment

- Visualization of AKD onto cellulosic nanofibers thanks to FE-STEM 33

Conclusions on Coating Colors

- Possibility to fill C.C with NFC-CTP and NFC-AKD

- Increase of the viscosity between “pure” C.C and “filled” C.C

- Diminution of viscosity between C.C filled with NFC-CTP and C.C filled with NFC-AKD

34


Good impact of chemical modification on coating

color viscosity

THANKS FOR YOUR ATTENTION

• Karim Missoum (PhD student in chemical engineering and material science)

[email protected]

Phone Number : +33 4 76 82 69 87

• Julien Bras (associate professor in Converting – Biomaterials – Packaging science)

[email protected]

Phone Number : +33 4 76 82 69 15

35

mailto:[email protected]






Acknowledgement

• The research leading to these results received funding

from the European Community’s Seventh Framework

Programme under Grant Agreement No 228802.

final conference 19.6 - sunpapsunpap.vtt.fi/pdf/final_conference/5_sunpap_missoum_2012.pdffinal...

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