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Metal Replacement – High Performance Plastics for Healthcare

Presented by a Network of Industry ExpertsSolvay Specialty Polymers Maria Gallahue-WorlQuadrant EPP Jim HebelPMC Jay Haverstraw

OMTEC – June 15, 2011

© 2011 Solvay Specialty Polymers2

Agenda

SOLVAY SPECIALTY POLYMERSIntroductionHealthcare market today – trending towards high performance plasticSelection criteria – Which plastic do I use?

QUADRANT EPPWhy Choose Stock ShapesHow to be Successful Designing with Plastic ShapesEvolution of Plastics and Application Examples

PMCWhen to Choose Injection MoldingDesign BasicsInjection Molding Process OverviewTooling, Moldability and Case Studies

Guided Tour – Converting Pellets to a Plastic Part


Solvay Group – Who are we?

International Industrial Group Active in Chemistry

EUR 7.1 billion Turnover in 2010

16,800 employees in 40 countries

Pending purchase of Rhodia will add EUR 5.2 billion in sales and 14,000 employeesHeadquarters in Brussels, Belgium

Solvay Solexis

Solvay Advanced Polymers

Solvay Padanaplast

SolVin PVDC

Four Leading Companies Create One Global Business Unit


Solvay Specialty Polymers …

Leading in discovering, developing and deliveringhigh-performance specialty polymersthat meet the challenges facing society


Fluorinated Fluids

Fluoro/Perfluorelastomers

Partially-Fluorinated Polymers

Fluoropolymer Coatings

Fully-Fluorinated Polymers

Polymer Processing Aids

Cross-Linkable Compounds

Spire® Ultra Polymers

Solviva® Biomaterials

Sulfone Polymers

Semi-Aromatic Polyamides

Liquid Crystal Polymers

High-Barrier Polymers

PRODUCT FAMILIES

More Products with More Performance™


Summary of Healthcare Trends

Healthcare trends influencing material selection

Pressures to control costs

Long-term benefits by shifting away from all-metal implants

Ever-changing regulatory environment

Focus on preventing spread of infectiousdiseases

Desire to improve practitioner comfort

Differentiation of products using color

Ability to improve efficiency of procedures


External Factors - Costs

Driving cost pressures

Challenging insurance reimbursement climate globally

Healthcare reform legislation in US

Excise tax - $20B over 10 years

More limited venture capital funding

Get product to market as cheaply and quickly as possible


Internal Factors - Costs

Cost of high performance metal & metal alloys

Expense associated with producing & maintaining metal instruments

High central service costs

Effect on Material Selection

Single-use instruments

Metal-to-plastic conversions

Replacing metal with plastics can lower costs


Shift Away from Metals - Implants

Metal-on-Metal ImplantsConcern related to toxicity due to metal particulates

Stress Shielding in load bearing componentsBone resorption leads to higher revision rates

Effect on Material SelectionHybrid technologies incorporating both metals, plastics and other materials

Opportunities for materials with strength to weight ratio similar to bone

Metal-to-plastic conversions for all applications


Regulatory Requirements

Challenging regulatory landscape

Evolving requirements for 510(k) clearance

More stringent CE Mark requirements

Greater requirements on all tiered suppliers


Materials desired that have precedence and known regulatory path

Onus on raw material suppliers to provide extensive data to support biocompatibility of materials


Preventing Spread of Infectious Disease

Hospitals must control the spread of infectious disease, especially resistant microbes

More aggressive cleaners and disinfectants used on more devices and equipment


Pushing the performance limits of many traditional plastics, such as PC/ABS blends


Practitioner comfort

Ergonomic designs

Reduce fatigue

Improve comfort and control


Overmolded silicone grips

Metal-to-plastic conversions

Lightweight plastics improve practitioner comfort


Stand out in a competitive marketplace

Visual communication

Create brand awareness


Biocompatible pigments

Autoclavable colored plastics

Colored plastics give you the look you want and the performance you need

Product differentiation


Improved Efficiency

Lower costs & reduce potential for errors

More Efficient Procedures Improve inventory tracking and management

Quick visual confirmation

Placement verification

Effect on Material SelectionRFID tags

Color coding

Transparency

Radio-opacity


Overwhelming Number of Plastics Available

How do I find the best plastic for my healthcare application?


Key Criteria for Healthcare Applications

Six Key Considerations for Material Selection

1. Duration of Contact

2. Biocompatibility

3. Product Life Cycle

4. Sterilization Method

5. Cleaning and Disinfecting

6. Property Requirements


Duration of Contact

How long is the device in contact with bodily fluids or surgically formed body cavity?

Limited Exposure <24 hoursProlonged Exposure >24 hours <30 daysPermanent Exposure >30 days

Important to confirm with the supplier that their materials are offered for use in implantable devices


Biocompatibility

Fundamental requirement

Testing standards are defined by ISO 10993:1-2009 and FDA G-95 Guidance document

based on duration and type of contact with human body

USP Class VI compliance is typically not sufficient, especially for implantable devices

Does your material supplier have an Master Access File (MAF) registered with the FDA and, if so, how/when may you receive an access letter?

MAF’s typical for materials used in implantable devices but not typically available to those used in limited exposure devices


Product Life Cycle

Single-Use Devices

Sterilized once

Cleaning & disinfecting are not required

As-molded properties

Reusable devices require higher performing plastics

Reusable Devices

Sterilized repeatedly

Cleaned & disinfected repeatedly

Long-term properties(up to 3+ years)

OR


Sterilization Method

High-Energy Gamma RadiationRadiation kills microorganism(25 or 40 KGy)Common for single-use devices

Ethylene Oxide GasDisrupts microorganism’s DNA to prevent reproductionFor materials that degrade with heat or irradiation

Vaporized Hydrogen PeroxideLow-temperature sterilizationCycle times 30 or 40 minutes

Methods

Steam AutoclavePressurized steam up to 134C for 20 minutes50 to 1,000+ cyclesCommon for reusable devices


Compatibility with Sterilization Methods

Only plastics with high heat resistance and excellent hydrolytic stability can withstand repeated steam sterilization

PEEK

Steam (up to 134°C for 18 minutes)

Ethylene Oxide

Hydrogen Peroxide

Gamma Radiation

10 cycles

500 cycles

1,000 cycles

100 cycles

25 cycles 40 kGy

Polycarbonate

Polysulfone

Polyphenylsulfone


Chemical resistance varies greatly among plastics and is largely dependent on molecular structure

Other influential factors include

Type of reagent

Temperature

Reagent concentration

Frequency of exposure

Stress on fabricated part

Cleaning & Disinfection


Compatibility with Common Disinfectants

at Room Temperature PC PSU PPSU PEEK

Bleach Solution, 10%

CaviCide®

Cidex®

Enivirocide®

Manu-Klenz®

Quaternaries®

Sani-Cloth® HB

Vesphene® IISE

Wex-Cide®

Excellent

Good

Poor

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Excellent

Good

Good

Poor

Poor

Poor


Retention of Mechanical Properties

Look past the data sheet (as-molded properties)

Strength and toughness for the life of the product (2-3 years)

1,000+ cycles of cleaning, disinfecting and steam sterilization

Property Requirements

Consider the cumulative effects of chemical environment and sterilization method


Criteria to Narrow Material Choices

Product Life Cycle

Biocompatibility

Retention of Properties

Sterilization, Cleaning and Disinfection

Depends on level of compliance needed

PC, ABS, PC/ABS, PARASingle Use Reusable

PSU, PPSU, PEEK

PSU, PPSU, PEEK

PPSU, PEEK

Increased performance requirements significantly decreases the number of suitable materials

Duration of ContactNon-Implant Implant

PSU, PPSU, PEEK, PEKKPEI, PSU, PPSU, PEEK


Now What?

Designing in PlasticIsn’t Harder

It’s Just Different

Quadrant – Who are we? How do we fit?

Why Choose Stock Shapes

How to be Successful Designing with Plastic Shapes

Evolution of Plastics and Application Examples

Agenda Topics

• Polymer Corporation

• Polypenco

• DSM Engineering Plastic Products

• ERTA Inc.

• Symalit

• Poly-Hi Solidur

A global company formed by joining top regional leaders:• Quadrant consists of over 2,400 employees located in 43 sites around the world. Corporate

headquarters in Zurich, Switzerland.

• Currently an all plastics company owned by 50% Mitsubishi Plastics.

• Heavy focus on Advanced Engineered Thermoplastic STOCK SHAPES.

Quadrant Engineered Plastic Products

Over 60 years of innovation in engineering plastics

Part size

Production quantity

Large

800 kg

Small

0.01 kg

Medium

Low

1 pcs

High

10,000 pcs

Custom Casting- best choice for large parts of any quantity- economical alternative to machining

for quantities as low as 50 pcs- several parts can be made from one mould,

improving design, flexibility and costLow Pressure Casting

Machining- limited to stock size availability- high production cost for 500 or more piece quantities

Injection molding- Cost effective for high

volume parts.- High design and

tooling cost.- Size and shape

limitations.

Some Pellet-to-Part Conversion Options?

Why Choose Stock Shape Thermoplastics?

What is a stock shape thermoplastic?

• Rod, sheet, tube that can be machined into a final component.

• Standard materials to highly specialized Advanced Engineered materials.

Why choose a stock shape thermoplastics?

• Prototype Parts

• Small volume machineable quantities where cost of injection molding tool is not cost effective.

• Size and shape is not conducive to injection molding.

Biocompatibility – Available on Shapes Too!!

Quadrant’s Life Science Grade (LSG) Materials - Full range of biocompatibility testing on stock shape material in full accordance with USP and ISO 10993 guidelines.

QUADRANT LSG PC

QUADRANT LSG PSU

DURATRON LSG (Ultem) PEI

QUADRANT LSG (Radel) PPSU

KETRON® LSG PEEK

KETRON® - CA30 LSG PEEK

KETRON® - GF30 LSG PEEK

ACETRON® LSG 7 colors POM

Proteus® LSG PP (heat stabilized)

• - Systemic Toxicity (acute)

• - Intracutaneous Reactivity

• - Implantation test

• - Sensitization

• - Cytotoxicity

• - Human blood compatibility

• - USP-Physicochemical

• - Heavy metal content

USP VI

ISO

USP V

ISO

ISO

ISO

ISO

ISO

Documentation of Test Results accompany every material shipment.

Why Choose Stock Shape Thermoplastics?

75°C

140°C

240°C

PE-LD

PE-HD

POM

PA

PAI

PET-P

PBT

UHMW-PE

PPS

PP

P E E K

PTFE

PMMAABS

PS

PVC

PC

P B I

PPSU

PSU

PPO

P E I

a m o r p h o u s(transparent)c r y s t a l l i n e

T h

e r m

a l

/ C h

e m

i c

a l

P e

r f o

r m

a n

c e

465°F

285°F

165°F

General Purpose

Engineering Plastics(GEP)

Advanced Engineering

Plastics(AEP)

Commodity Plastics

660°F / 350°C

Broad Material Portfolio – Material Selection is Critical


Avoid the common pit-falls which can lead to “failures” resulting in lost time, lost money, and lost confidence in your plastic design.

Often times, such failures are the result of poor material selection or poor design.


Reasons for machined plastic component failures?• Temperature or chemical exposure• Improper clearance• Cracking due to impact or fatigue• Unable to hold desired tolerances• Material movement…i.e. bowing or warping

Component design with machined plastic is much different than traditional materials.

Machining with Plastics is not hard.Machining with Plastics is just different versus traditional materials.

Understanding a few simple tips can make the difference!

Simple Design Modifications and the Right Approach can make the difference:


Machining• Heat generation during machining is one of the largest problems we see and

can lead to tolerance limitations, brittleness, burring, poor surface finish, and rapid tool wear.

• Factors critical to machining success:Fixturing techniquesProper feed-rates and tooling speedsProper tooling and correct geometriesUse of water-based coolant


Tolerance Expectations for Machined Parts:

• Keep the part cool during machining to maintain tolerance control. Utilize Quadrant recommended machining guidelines.

• For typical thermoplastics expect to hold 0.1% to 0.2% tolerance on all dimensions.

• For tighter tolerance control, consider rough machining (within .030”) and allowing the part to stress relieve for 24 to 48 hrs.

Extreme Finish:Vapor polished medical components.

Simple Design Modifications and the Right Approach can make the difference:


Increase Strength and Toughness:• Where possible, we recommend putting a radius on any

sharp corners (.020” to .030” radius).• When threading into plastic, always use a coated tap.

Proper Running Clearance:• Self-lubricated polymer bearings are maintenance

free and offer extended wear life.• To fully recognize these benefits, proper running

clearance is critical.

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Evolution of Plastics & Application Examples

Traditional Plastics– UHMW PE– nylon (PA)– acetals (POM)– Polycarbonate– PEEK

Improvedperformance

Advanced Plastics withEnhanced Technology:– Ertalyte TX PET (240° F)– Quadrant Udel PSU (350° F)– Quadrant Radel PPSU (380° F)– Duratron Torlon PAI (532oF)– Duratron PBI (up to 800° F)

Highestperformance

Metals– stainless steel– aluminum– bronze– cast iron

Standardperformance

Ongoing Materials Evolution

Newer materials, blends, &

fillers continue to push

performance envelope

Case Study – Fluid Control Valve

Problem: Aggressive fluids resulted in corrosion problems in metal components and unreliable service.

Benefits:• Corrosion of parts was completely eliminated• Bonus of weight savings vs metal equates to higher fuel efficiencies • Dimensional control improved via lower CLTE vs Vespel• Lower part cost for Duratron (Torlon) T4203 PAI vs Vespel

Duratron® (Torlon®) PAI

Application: Precision Fluid Control Needle Valve Accurate and reliable fluid control on a commercial airplane is maintained via this miniature valve.

Application Requirements:• Dimensional stability via low CLTE and fine machining features• Minimal dimensional change at temperatures down to -50° F• Resist aggressive fluids and aircraft fuel.

Stainless Steel

Material Evolution

Vespel® PI

®Vespel is a registered trademark of DuPontTorlon is a registered trademark of Solvay Advanced PolymersDuratron is a trademark of Quadrant EPP

Case Study – Surgical Instrument

Problem: Prior materials did not offer ideal transparency combined with repeat autoclavablity for long life.

Benefits:• PSU provided significant increase in autoclavability vs polycarbonate for added part life• Quadrant’s Life Science Grade (LSG) PSU offered biocompatibility certification on stock shape for

added peace-of-mind• Surgeons greatly preferred improved transparence vs Ultem

Quadrant (Udel®) PSU

Application: Breast Cancer Treatment Applicator.Surgeons required pin-point accuracy and clarity for applicator placed directly in tumor bed. Used to deliver low energy, high dosage and spare surrounding tissue.

Application Requirements:• ISO 10993 / USP biocompatibility for 24 hour contact• Optical clarity with excellent machinability /polishing for fine features• Resist repeated steam exposure

Polycarbonate

Material Evolution

Ultem® PEI

®Ultem is a registered trademark of DuPontUdel is a registered trademark of Solvay Advanced Polymers

Case Study – Medical Device

Problem: Prior materials were too heavy and repeated autoclave cycles resulted in corrosion and material breakdown.

Benefits:• PPSU provided significant increase in autoclavability vs other polymers for added part life.• Quadrant’s Life Science Grade (LSG) PPSU offered biocompatibility certification on stock shape for

added peace-of-mind

Quadrant (Radel®) PPSU

Application: Surgical Instrument TraysLife Science Industry requires long-life, light-weight, and durable material for surgical instrument caddy.

Application Requirements:• ISO 10993 / USP biocompatibility for 24 hour contact• Dimensional stability with excellent machine-ability for tolerance control.• Resist repeated steam exposure

Stainless Steel

Material Evolution

®Radel is a registered trademark of Solvay Advanced Polymers

Tips for the Design and Maintenance Engineers

• documented ISO Quality Systems with the capability to provide lot-to-lot traceability, specification review, and material certifications.

• technical support including, application and design assistance

• assistance and support that will enable you to shorten the learning curve associated with selecting and machining plastics.

• a technical safety net that offers people and resources to assist in your project.

When selecting machineable plastics look for:

www.quadrantepp.com

Goto “Machinist’s Toolkit”

PMC, LLC Confidential Information 42PMC, LLC Confidential Information

Fundamentals of Injection Molding

Who is PMC

When to choose injection molding

Functionality considerations

Design basics

Injection molding process overview

Part moldablity and tooling implications

Case Study


Who is PMC?

HistoryContinuous operation & private ownership since 1929Markets served

Medical, Commercial Electronics, Automotive

Medical Market Focus1. High-Temperature & Implantable Biomaterials

Implantable devices and instrumentation

Metal-to-plastic conversion expertise

Innovative process development of new materials and applications

Variety of specialty, high-temperature & biomaterialsPEEK, TPU, PPS, PPSU, PSU, Ixef® (Polyarlyamide), Bioabsorbables

Highly-filled materials (Glass (standard & long), Minerals, PTFE, Carbon (Fiber & Black), Silicone)

2. Medical/Surgical Device & Instrumentation• Injection molding & complete contract manufacturing of finished devices

• Special vertical molding machine for innovative insert molding of instruments

• Assembly, kitting and sterile packaging


Manufacturing Process Selection

When is injection molding a good choice?Higher volume – >500

Low cost per partHigher initial investment - $10k or more

Complex geometryPart cosmetics – colors, texturesInsert molding – bi-material assembliesPart design strength requirements benefit from flow orientation and fiber alignment.Tight tolerancesScrap reduction


Functionality – End Use Environment

AssemblyAssembly techniques may dictate material selection.

Production quantitiesThe number of parts needed may influence decisions, including processing methods, mold design, material choice, assembly techniques, and finishing methods.

Cost constraintsMarket will only bear a finite cost.

Processing Processing method will effect design.

StressTensile, compression, flexural, torsion, shear, cyclic, impact


Functionality - Environmental exposure

Consider all environments - manufacturing, shipping, sterilization, storage, end-use, disposal

TemperatureChemical ExposureElectrical Performance – insulate or conduct? Weather Resistance – Humidity, UV.Radiation – Light and sterilizationAppearance – Color, light transmissivity, texture.Agency Approvals – USP Class VI, ISO 10993.Life Expentancy – reusable or single use?


Part Geometry – Nominal Wall Thickness

Nominal Wall ThicknessSelecting the proper nominal wall thickness is one of the first and most important part design decisionsMaintain uniform wall thickness to minimize part warpageand dimensional control problems


Part Geometry – Nominal Wall Thickness

Core out or redesign thick sections for a more uniform wall thicknessWhen wall thickness can not be uniform, round or taper the thickness transitions to minimize molded-in stress


Part Geometry – Ribs

To increase part stiffness, ribs are typically a better option than increasing nominal wall thickness

Ribs widths should not exceed 80% of nominal wall to avoid causing sink marks or surface blemishes.For a given stiffness, it is better to increase the number of ribs rather than the height.

For thick ribs "core out" the rib from the back to maintain a uniform wall thickness.


Part Geometry – Holes

Holes are easily produced in molded parts.Core pins that protrude into the mold cavity make the holes when the part is molded. Through holes in molded parts are easier to produce than blind holes, which do not go all the way through a part. Blind holes are made by core pins supported on one end only. The pins can be deflected and pushed off center by the pressures of the molten plastic material during the molding process.


Part Geometry – Bosses

Bosses are used for locating, mounting, and assembly purposes.

Avoid bosses that merge into sidewalls. Use ribs and gussets for support.Avoid tall bosses – required draft can cause the top of the boss to be too thin to fill or the bottom of the boss too thick. Also, long thin core pins are difficult to core properly. Consider using cores from both sides or gussetsBoss wall thickness should be less than that of the nominal wall to avoid sink and warp issues.


Injection Molding Machine/Process Overview

Plastic pellets are normally dried and fed through a hopper into the reciprocating screw.The material melts as it travels forward when the screw turns.Screw movement forces the molten material into the moldAfter the material in the mold solidifies, the mold opens and the part is ejected.


Moldability

Moldability is the ease with which a material is processed in the part design. The key elements of the molding sequence are:

Fill → Pack → Cool → Eject


Moldability – Fill & Pack

Fill – The first stage of plastic injectionFlow length — the distance from the gate to the last area fill — must be within acceptable limits for the plastic resin chosen. Excessively thin walls may develop high molding stresses, cosmetic problems, and filling problems

Pack - Adding material to the mold for complete fill of the cavity and for compensating the shrinkage that occurs during cooling.


Moldability – Cool & Eject

Part design has a large impact on part cooling.Uneven wall thickness will cause a cooling rate differential within the part.

Differential shrink causes molded-in stress which can lead to part warp.

The increased shrink of thicker wall sections can cause the formation of sink marks on the outside wall of the part or internal, non-visible voids.

Eject - Cooling is complete when a dimensionally stable part can be ejected without distortion or excessive stress.


Anatomy of an injection tool


Tooling Considerations – Gate Location

Defines flow direction and lengthDefines weld line positionGate into the thickest sections to avoid packing problems and sinkLocate gates so material flows in the direction of reinforcement structures (ribs)Consider cosmetic requirementsAvoid gating into or near areas that will be subject to high levels of applied stress


Tooling Considerations – Weld Lines

Holes in the nominal wall will divide the material flow into two fronts. The point at which the two flow fronts rejoin on the opposite side is called a weld line.

Weaker than surrounding plastic material, especially with reinforced thermoplastics.Define gate location to keep weld lines in a low stress area of the part.Can exhibit poor cosmetics.


Tooling Considerations – Draft

Draft - providing angles or tapers on product features that lie parallel to the direction of release from the mold eases part ejection.

Draft all surfaces parallel to the direction of steel separationAngle walls and other features that are formed in both mold halves to facilitate ejection and maintain uniform wall thicknessAdditional draft is needed for textured surfaces.


Tooling Considerations – Undercuts

Undercuts are design features that place portions of the mold in the way of the ejecting plastic part.

Some undercuts can be stripped off of a core.Most undercuts need complex mold actions to create; however, clever part design can eliminate these expensive tooling investments by using bypassing steel or through holes


Metal to Plastic ConversionCase Study 1

Orthopedic targeting guide

Objective: To replace a titanium device with a lower cost polymer design

Design Challenges: Maintain the required tolerance between the proximal and distal

guide locatorsMeet the cost targets with an annual volume of less than 2000

units

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Solutions:Polymer w/ metal insert option

Metal insert added $40 to the part costTooling cost increased to add features to retain the metal insert

Polymer solutionSelected high flow composite materials with optimal flex modulusDesigned an I-beam profileModified gate size and nominal wall thickness to optimize the orientation of carbon fiber Mold flow and FEA utilized to refine the design

Cost Map:Titanium Design $ 300 (appox)Polymer w/ metal insert $ 90Polymer $ 20

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Orthopedic CannulatedGuide

Objective: To replace a costly titanium guide

Design Challenges: This guide is anchored to the bone at the surgical site using a

serrated featureInjection molding features with sharp points requires special

tooling features or secondary operationsAnnual volumes of less than 1,000 units

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Solutions:Polymer w/ metal insert option

Insert molding a titanium insert with sharp pointsInsert cost and tooling costs were not attractive

Polymer solutionSelected Solvay Ixef material (High flow + high flex modulus)Molded sharp points with no flash or secondary operations

Cost Map:Titanium Design $400+ with chronic quality issuesPolymer w/ metal insert $ 70Polymer solution $ 15

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Injection Molding Key Points

Injection molding offers superior cost advantages for mid to high volume product applications

Good injection molded plastic part design begins with a full definition of all part requirements and selection of a material that will satisfy those requirements

Component geometry must follow basic rules for molded part design

OEM, injection molder, and material supplier should work cooperatively early in the design cycle to insure successful product design and manufacturing execution

PMC, LLC Confidential Information 66


Tradition of Scientific Innovation

SOLVAY’S Council of Physics - 1911

Solvay

Einstein

Curie

Rutherford

Nernst

Planck


Summary

There is a trend toward high-performance plastics in the healthcare industry

Use key performance criteria to target material selection

Designing in plastic – it’s not hard, just different

There are multiple ways to achieve a plasticsolution that fits the needs of theapplication and project

For best chance of success – engageyour plastic supply chain expertsearly in your design


How can wehelp you?

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