PLASTICS MATERIALS

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PLASTICS MATERIALS Powered By Docstoc
					                   Solid Materials

 Metals                      Plastics              Ceramics


Thermo -settings                                 Thermoplastics


   Commodity                 Engineering              Specialty




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                       PLASTICS
THERMOPLASTICS                         THERMOSETTING PLASTICS
• Linear or slightly branched          • Do not form linear chain –
  polymer –                              forms 3 –dimensional
  addition/condensation                  structure
• Repeated softened at                 • Hard and infusible and
  elevated temperature and               cannot be softened without
  solidified on cooling                  decomposition
• No chemical changes occur            • Molecules are held by
• Molecules are held by                  primary forces.
  secondary forces


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FAMILIES OF POLYMER MATERIALS




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Polymers are a large class of materials consisting of many small molecules (called
monomers) that can be linked together to form long chains, thus they are known
as macromolecules




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          Amorphous Vs Crystalline
An amorphous solid is formed when the chains have little orientation
throughout the bulk polymer. The glass transition temperature is the
point at which the polymer hardens into an amorphous solid. This term
is used because the amorphous solid has properties similar to glass.

     In the crystallization process, it has been observed that relatively
short chains organize themselves into crystalline structures more readily
than longer molecules.

     Therefore, the degree of polymerization (DP) is an important
factor in determining the crystallinity of a polymer. Polymers with a high
DP have difficulty organizing into layers because they tend to become
tangled
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Thermoplastics From melt to solid




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 Various Thermoplastics
                                       PI
Specialty
                               PSU PTFE
Polymers                             LCP
                             PES
                              PPSU    HPPA

Engineering                              PA
Polymers                      PC         POM
                                                  PET
                       PPO               PBT
                                           TPE
              ABS         PMMA
Commodities                               PP-GF    PE-UHMW
              PS             PVC
                                            PP            PE-HD
                    SAN                           PE-LD

              AMORPHOUS                       CRYSTALLINE



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               Why Use Thermoplastics?
   Increased performance
               Corrosion resistance
               Weight reductions (specific strength & stiffness)
         Cost reduction!
               Parts consolidation & net shape formation
               Process elimination (painting, machining, assembly)
               Economics of injection molding
    Properties can be altered to suit the needs
    Good strength/weight ratio
    Tough & durable
    Non toxic
    Easy processability
    Chemical/Moisture Resistant
    Fire retardant
    Do not rust/corrode.
    Resistant to microbes
    Attractive colours
    Good weatherability
    Practically maintenance free
    Reusable / Recyclable


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Low Density Polyethylene
        (LDPE)




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STRENGTHS                                                   LIMITATIONS

• Very low cost                                               • Susceptible to environmental stress
• Excellent chemical resistance                                 cracking
• Very good process-ability
                                                              • Low strength, stiffness and maximum
• High impact strength at low     temperature                   service temperature
• Excellent electrical insulating properties
• Very low water absorption                                   • High gas permeability, particularly carbon
• FDA compliant
                                                                dioxide
• Can be transparent in thin film form
                                                              • Poor UV resistance
• Since it is non-polar, electrical properties are
 almost independent of temperature and frequency              • Highly flammable
• Tg is well below the room temperature
                                                              • High-frequency welding and joining
                                                                impossible

                                                              • Poor scratch and abration resistance



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                      Processability
                              General information

The most common process used for LDPE is extrusion (tubes, blow and cast films,
cables, ...). LDPE can also be processed by injection molding or rotomolding.



                                     Extrusion

Melt temperature : 180-240°C
Higher melt temperatures are needed for extrusion-coating (280-310°C).
A three zone screw with a L/D ratio of around 25 is recommended.



                                Injection molding

Melt temperature : 160-260°C
Post mold shrinkage lies between 1.5 and 3.5 %.


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  Applications                                            Key performances

 Packaging

                                                           •Low cost
Pharmaceutical and squeeze bottles
                                                           •Processability
                                                           •Flexibility

Caps and closures                                          •Low cost
Tamper evidents                                            •High flexibility
                                                           •Processability

Liners
Trash bags                                                 •Low cost
Films for food packaging (frozen, dry goods ...)           •High flexibility
Laminations                                                •Processability

Consumer goods

Housewares                                                 •Low cost
                                                           •Processability
Flexible toys                                              •Flexibility

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Applications                                             Key performances

Agriculture
                                                    •Low cost
Agricultural films                                  •Good mechanical properties
                                                    •Processability, excellent drawdown
Pipes & Fittings

                                                    •Low cost

Water pipes and hoses                               •Excellent chemical resistance
                                                    •Very low water absorption
                                                    •Processability
Wiring & Cables

                                                    •Low cost
Sub-conductor insulators
Cable jacketing                                     •Good electrical insulating properties
                                                    •Processability


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Linear Low Density Polyethylene
               (LLDPE)




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                Strengths                                        Limitations
• Higher tensile strength than LDPE               • Lower gloss than LDPE

• Higher impact and puncture resistance           • Narrower temperature range for heat
  than LDPE                                         sealing than LDPE

• Lower thickness films can be blown              • Lower processability than LDPE
  compared to LDPE
                                                  • Susceptible to stress cracking
• Improved sealability
                                                  • Lower stiffness than polypropylene
• Excellent chemical resistance
                                                  • High mold shrinkage
• Very good processablity
                                                  • Poor UV resistance
• High impact strength at low temperature
                                                  • Low heat resistance
• Excellent electrical insulating properties
                                                  • High-frequency welding and joining
• Very low water absorption                         impossible

• High environmental stress crack
  resistance
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                               General information

The most common process used for LLDPE is extrusion (tubes, blow and cast films,
cables, ...). LLDPE can also be processed by injection molding or rotomolding.



                                      Extrusion

Melt temperature : 205-260°C
A three zone screw with a L/D ratio of around 25 is recommended.



                                 Injection molding

Melt temperature : 160-260°C




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  Applications                                             Key performances

 Packaging
Bags and pouches                                  •Low cost
Films for food packaging (frozen, dry             •High flexibility
goods)                                            •Processability
Agriculture
                                                  •Low cost
Agricultural films                                •Good mechanical properties
                                                  •Processability, excellent Drawdown
Pipes & Fittings

                                                  •Low cost
                                                  •Excellent chemical resistance
Water pipes
                                                  •Very low water absorption
                                                  •Processability

Wiring & Cables
                                                  •Low cost
Cable jacketing
                                                  •Good electrical insulating properties
Cable insulators
                                                  •Processability
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    Applications of LDPE & LLDPE




Green House                            Bottle Caps




Cable Sheathing                          Pouch
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High Density Polyethylene
            (HDPE)




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                           Strengths                                    Limitations


•Higher notched impact strength than other PE
•Higher wear resistance than other PE                      •Not melt processable
•Higher energy absorption capacity at high stress
rates than other PE                                        •Higher Cost than PE
•Higher heat deflection temperature than other PE
•Higher stress crack resistance than other PE
•Very low water absorption
•FDA compliant
•Good thermal stability
•Tg is well below room temperature
•High tensile strength, stiffness, creep resistance,
abrasion resistance than LDPE
•Non-polar in nature
•Very good chemical resistance
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                                General information

PE-UHMW is not melt processable, because of its extremely high viscosity. It can be
processed by ram extrusion and compression molding.

  Applications                                          Key performances
 Engineering

                                              Excellent sliding properties
 Linings of bunkers, silos and hoppers        High wear resistance
                                              High toughness


                                              Low friction with metal
 Conveying applications (bottling,            High wear resistance
 packing and transport equipment)             High impact strength
                                              Noise reduction


                                              Good corrosion resistance
                                              Excellent chemical resistance
 Pump casings
                                              Practical heat resistance
                                              Abrasion resistance
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Polypropylene
           (PP)




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                    Strengths                                         Limitations
•Low cost                                                  • Poor resistance to UV, need to
•Good chemical resistance against most                      be stabilized
inorganic acids, alkalis, and salts                        • Embrittles below -20°C
•Good resistance to environmental stress                   • Low upper service temperature,
cracking when in contact with alcohols, esters,             90-120C
detergents, or polar hydrocarbons                          • Attacked by highly oxidizing
•Very good fatigue resistance                               acids, swell rapidly in chlorinated
•Very low density                                           solvents and aromatics
•Excellent dielectric properties                           • Heat-ageing stability is adversely
•More rigid than PE and retains mechanical                  affected by contact with metals
properties at elevated temperatures                        • Post moulding dimensional
•Mechanical and electrical properties unaffected            changes due to crystallinity
by submersion in water                                      effects
•Can be FDA compliant                                      • Limited impact resistance
•Good resistance to steam sterilization                    • Low scratch resistance
•Excellent hinge characteristics                           • Poor paint adhesion
•Can be joined by hot-gas, hot-tool, induction, or
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                               General information

These resins are not hygroscopic and may be used as received without need for
drying.
At temperatures above 220ºC, EVA resins can evolve toxic fumes.

                                 Injection molding
Melt temperature : 180 - 300°C
Mold temperature : 20 - 60°C. Higher the mold temperature then better the surface
gloss.
High injection pressure and speed are recommended.
                                      Extrusion

A three-zone screw with a total L/D ratio of 20-25 is generally recommended.
Melt temperature is, generally, in the overall range of 240-270ºC .

                                    Blow molding

Melt temperature should lie between 190 and 220°C.
Mold temperature should lie between 20 and 40°C.


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Applications                                               Key performances

Packaging
                                                      Low cost
Flexible packaging (Food and                          Good barrier properties
confectioneries, Tobacco, Clothin ...)                Good processability
                                                      Good puncture resistance

                                                      Low cost
                                                      Good processing stability
Rigid packaging (crates, bottles, pots ...)
                                                      High strength
                                                      Good surface finish

                                                      Low cost
Caps and closures for beverage and                    Good processing stability
cosmetic applications                                 High strength
                                                      Good surface finish

Fibers / Textiles / Carpets

Nonwovens                                             High flexibility
Film tapes                                            Good resistance to rupture
Strapping ...                                         Good chemical resistance
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Applications                                       Key performances

Health Care

                                             •Sterilization resistance
Syringes
                                             •Good chemical resistance

                                             •Transluscent
Household products / Consumer goods

                                             •Good cost to impact balance
Transluscent parts
                                             •Excellent processability

                                             •Transluscent

Housewares
                                             •Good cost to impact balance
Furniture
Appliances
                                             •Excellent processability
Luggage
Toys
                                             •Long-term use
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Polyvinyl Chloride
           (PVC)




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            Strengths                                        Limitations


Rigid PVC
•Low cost                                             •Difficult to melt process
•High stiffness                                       •Becomes brittle at 5°C (when not
•Intrinsic flame retardant                            modified with impact modifiers and/or
•Suitable for transparent applications                processing aids)
•Better chemical resistance than plasticized          •Limited solvent stress cracking
PVC                                                   resistance
•Good electrical insulation properties                •Low continous service temperature of
•Good vapour barrier properties                       50°C
•FDA compliant
•Good dimensional stability at room
temperature



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                               General information

Thermal stabilization is required for processing rigid PVC, otherwise material may
decompose during processing.
PVC is sensitive to the thermal history and the window of processing temperatures is
quite small.
Drying before processing is highly recommended, moisture rate should be lower than
0.3%.



                                 Injection molding

Melt temperature should lie between 170 and 210°C.
Mold temperatures of 20 to 60°C are more suitable.
Mold shrinkage lie between 0.2 and 0.5%.
Screw with an L/D ratio of 15 to 18 is recommended.

                                      Extrusion

Extrusion temperatures are 10-20°C below injection molding temperatures in order to
avoid premature thermal degradation.
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Applications                                            Key performances

Electrical
Insulation pipes
Jacketing                                          •Low cost
Electricity distribution boxes
Switches                                           •Good electrical properties
Transparent distributor box housings
Plug housings                                      •Stiffness
Battery terminals
                                                   •Inherent flame retardant
   Engineering

Pressure pipes
                                                   •Low cost
Ventilation ducts
Thermostat housings
                                                   •Versatile performance profile
Fittings
Pipe connections
                                                   •Stiffness
Claddings
Ventilators
                                                   •Good chemical resistance


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Applications                                           Key performances

Building and Construction
Waste water pipes and fittings
Grating covers
Fencing                                                 •Low cost
Decking
Siding                                                  •Processability
Drain pipes
Roofing sheets                                          •Stiffness
Sanitary installations
Window profiles                                         •Flame retardant
Fascia boards
    Consumer goods

                                                        •Low cost
Toys
Vases                                                   •Stiffness
Cases
                                                        •Processability

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 Applications                                              Key performances

Packaging
                                                              •Low cost
Disposable pots
Spice and cream containers
                                                              •Practical stiffness
Ball point pen cases
Blisters
                                                              •Transparency
Capsules
Trifolds
                                                              •Processability
Bottles for vegetable oil, juices, wine or non-food
packaging (cosmetics ...)
                                                              •Good chemical resistance

Pipes & Fittings

                                                              •Low cost

Pipes Fitttings                                               •Practical stiffness and
                                                              impact strength

                                                              •Good chemical resistance
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        Strengths                                          Limitations

Flexible PVC
                                              •Properties can change with time, due to
•Low cost
                                              plasticizer migration
•Good resistance to UV
                                              •Tends to degrade at high temperatures
•Flexible
                                              •Attacked by ketones; some grades
•High impact strength
                                              swollen or attacked by chlorinated and
•Good resistance to acids, alkalis, oils
                                              aromatic hydrocarbons, esters, some
and many corrosive inorganic chemicals
                                              aromatic ethers and amines, and nitro-
Good electrical insulation properties
                                              compounds
•Non-flammable
                                              •Non suitable for food contact with some
•Easier to process than rigid PVC
                                              plasticizers
•Versatile performance profile
                                              •Lower chemical resistance than rigid PVC

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                               General information

Drying before processing is highly recommended, moisture rate should be lower
than 0.3%.



                                 Injection molding

Melt temperature should lie between 170 and 210°C.
Mold temperatures of 20 to 60°C are more suitable.
Mold shrinkage lie between 1 and 2.5%.



                                      Extrusion

Extrusion temperatures are 10-20°C below injection molding temperatures in order
to avoid premature thermal degradation.




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Applications                                         Key performances

Electrical
Cable and wire insulation
Plugs
                                            Flexibility
Cable jackets
                                            Good electrical properties
Sockets
                                            Low cost
Cable heads
Distributors
   Engineering
Gaskets
Stuffing boxes
                                            Flexibility
Pipes
                                            Versatile performance profile
Hoses
                                            Low cost
Coatings
Protective caps for pipes.
   Building and construction
Seals for windows and doors
Swimming bath linings                          Flexibility
Floor and wall coverings                       Good weathering resistance
Roofing                                        Low cost
Doorstops                                      Flame retardant
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Wire coverings
Applications                                       Key performances

Consumer Goods
Toys                                Flexibility
Handbags                            Good weathering resistance
Tablecloths                         Low cost
Cases                               Processability

   Sports & Leisures

Balls                               Flexibility
Ski sunglasse seals                 Good weathering resistance
Inflatable dinghies                 Low cost

   Footwear

                                    Flexibility
Shoe soles
                                    Good weathering resistance
Boots
                                    Low cost

   Gardening

                                       Flexibility
Garden hoses                           Good weathering resistance
                                       Low cost
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Applications                                                Key performances

Automotive

Car body seals                               •Flexibility
Dashboard skins
Artifical leather seats                      •Good weathering resistance
Sun visors
                                             •Low cost
Healthcare / Medical

                                             •Flexibility
Blood storage bags
Drainage tubes                               •Hemocompatible

                                             •Low cost




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Types of Profiles :
        Hollow Profiles
        Foam Profiles
 Doors :
       Aluminium Frame + Hollow
      Profile
       PVC Frame + Hollow Profile
       PVC Frame + Foam Sheet
 Door Frame
 Windows
       Sliding
       Casement
             Single Glazing
             Double Glazing
 Partitions
 False Ceiling
 Miscellaneous
 (Viz... Kitchen Cabinets etc.)




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Versatility of PVC

      From
     Footwear…..




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Polystyrene
          (PS)




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               Strengths                                    Limitations


•Low cost                                  •Brittle at room temperature
•Transparent
                                           •Poor mechanical properties above 70°C
•High stiffness
•Good dimensional stability                •Poor chemical resistance, especially to
•Good processability                       organic solvents

•Good electrical properties, low           •Susceptible to UV degradation
dielectric loss
•Excellent resistance to gamma             •Highly flammable
radiation
                                           •Limited resistance to organic solvents, when
•FDA compliant                             compared to polyolefins.
•Low moisture absorption
                                           •Possesses tendency to stress cracking
•Low mould shrinkage
                                           Low creep strength under repeated stress
•Very low thermal conductivity




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  High Impact Polystyrene
             Strengths                                      Limitations
Tougher than PS crystal                    Reduced transparency compared to PS crsytal

Low cost                                   Reduced electrical properties compared to PS
                                           crystal
Good dimensional stability
                                           Poor chemical resistance, especially to organic
Good processability                        solvents

Good electrical properties, low            Susceptible to UV degradation
dielectric loss

Excellent resistance to gamma              Highly flammable and toxic smoke
radiation


FDA compliant




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                                 General information

Crystal polystyrene can be processed by every conventional technique used for
thermoplastics.
Drying is normally not necessary. But if necessary (high transparency and high gloss
required), the product can be dried for 2 hours at about 80°C.



                                   Injection Molding

A melt temperature of 180-280°C is recommended.
Generally, mold temperature should lie between 30 and 50°C. For thin wall objects
moulded at short cycle times it could be useful to cool down the mould down to
10°C.
Mold shrinkage lies between 0.4 and 0.7% depending on the grade used.



                                        Extrusion

Grades with a high viscosity are suitable for extrusion.
A melt temperature of 180-220°C is generally used.
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Applications                                            Key performances

Packaging

                                                   Low cost
                                                   Ease of process and decoration
Food packaging                                     Food contact approvals
(dairy packaging, meat trays, egg cartons,         Possibility to be produced by lots
fruit and vegetable trays)                         Recyclability of the material
                                                   High stiffness



                                                   Low cost
Consumer packaging (cassettes and CD               Ease of decoration
shell and covers, jewel box ...)                   Ease of process
                                                   Possibility to be produced by lots
                                                   Recyclability


                                                   Ease of process
Industrial packaging (small foamed shapes          Low cost
...)                                               Recyclability
                                                   Possibility to be produced by lots
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 Applications                             Key performances

Consumer Goods
                                        Low cost
Toys                                    Processability
Cutlery                                 Available in a wide range of colors
                                        Low density

Disposables                             Low cost
(cups, forks, knives, spoons,           Recyclable
plates…)                                Processability
                                        FDA compliant

                                        Low cost
Shower stalls
                                        Ease of process
Door lights
                                        Possibility of printing and design
Envelope frames ...
                                        Safety when broken (contrary to glass for
                                        shower stalls for instance)
    Optics

                                          Transparency
Light diffusers                           Low cost
                                          Processability
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                                          Stiffness
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POLYMETHYLMETHAACRYLATE (PMMA)




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          Strengths                                         Limitations

•Outstanding transparency                             •Poor impact resistance


•Excellent UV resistance                              •Limited heat resistance (80°C)


•High color brightness and stability                  •Limited chemical resistance, attacked
                                                      by organic solvents

•Surface hardness
                                                      •Poor wear and abrasion resistance

•Half the weight of glass
                                                      •Cracking under load possible

•Good dimensional stability


•Good insulating properties


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                               General information

Pre-drying is not necessary if a vented cylinder is used but if a normal cylinder is
used then PMMA must be processed dry and it is advisable to pre-dry the granules
for up to 8 hours at 70-100°C. Surface defects and blisters will form if damp
granules are processed.



                                 Injection Molding

Melt temperature : 200-250°C
Mold temperature : 40-80°C
High injection pressures are needed because of poor flow properties and it may be
necessary to inject slowly to get the correct flow.



                                      Extrusion

Extrusion temperature : 180-250°C
A degassing screw with an L/D ratio of 20-30 is recommended.

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Applications                              Key performances

Building & Construction

Windows                         High transparency
Port-holes                      UV resistance
Domes                           Surface hardness
Optics
                                Optical properties
                                Transparency
Sunglasses
                                UV resistance
                                Surface hardness

                                Good optical performance
Diffuser panels                 Resistance to weathering
                                Hardness
                                Chemical resistance

                                High clarity
Watch glasses                   Lower weight than glass
                                High surface quality

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Applications                        Key performances

Automotive
                    Optical properties
Rear lights
                    Colorability
Indicators
                    Weathering resistance

                    High transparency and clarity
Dashboard covers    Scratch resistance
                    Chemical resistance

    Electrical

                    Transparency and excellent optical properties
Lamp covers         Processability
                    Chemical resistance

    Packaging

                    Transparency
Blister packaging   Hardness
                    Thermoformability
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Applications                                Key performances

Automotive
                                       Transparency
Pens                                   Gloss
                                       Goods processability
                                       Resistance to greases
Plates
                                       FDA compliant
Salad bowls
                                       Good surface finish
Healthcare / Medical
                                       Good processability
Toothbrushes                           Transparency
                                       Chemical resistance
                                       Optical clarity
Blood sample tubes
                                       Biocompatible
Diagnostic dishes
                                       Resistance to sterilization
Industrial

                                       High versatility
Point-of-purchase displays             Good compatibility with other materials
                                       Good surface finish
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ETHYLENE VINYL ACETATE (EVA)




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                    Strengths                                     Limitations

•Highly flexible , even at low temperatures
(-25°C)
                                                   Poor heat resistance


•Highly compatible with a lot of elastomers,
                                                   •Reduced barrier properties
TP and other materials (SBr, EPDM, TPE,
                                                   compared to LDPE
PE, PVC, asphaltum ...)


                                                   •Attacked by polar solvents,
•Better tear resistance than LDPE
                                                   hydrocarbons, oxydants and strong
                                                   acids
•Excellent resistance to environmental
stress cracking
                                                   •Reduced creep resistance,
                                                   compared to LDPE
•FDA compliant


•Good UV and ozone resistance

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                                General information

These resins are not hygroscopic and may be used as received without need for
drying.
At temperatures above 220ºC, EVA resins can evolve toxic fumes.

                                  Injection molding

Experience has shown screws normally used for injection molding of low density
polyethylene to be satisfactory.
Melt temperature : 150-200°C
Mold temperature : 15-40ºC

                                       Extrusion

A three-zone screw with a total L/D ratio of at least 20 is recommended.
Melt temperature is, generally, in the overall range of 95-205ºC .
The melt temperature depends upon the melt index of the resin, the % vinyl acetate
and the part configuration.


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Applications                               Key performances

Packaging

                                                         •High flexiblity
 Stretch film for shrink wrapping
                                                         •Good tear resistance

                                                         •FDA compliant

                                                         •Good sealability
 Sealable layer in multilayer food packaging
                                                         •Flexibility

                                                         •FDA compliant
 Personal safety/ Protection equipment

                                                         •High flexibility
 Flexible gloves
                                                         •Good resistance to rupture

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                                                         •Good chemical resistance     63
Applications                      Key performances

Automotive


                     •Good sound absorption
Sound proofing
                     •Good adhesion with many substrates
Footwear

                     •Good impact absorption
Soles (EVA foam)
                     •Good adhesion with many substrates
Wiring & Cables

                     •Good adhesion with many substrates
Wire coating
                     •Highly flexible




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Seals, Toys, Helmet Parts                       Corrugated Tubes




                 Shoe Components




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