Amorphous and Semi-Crystalline plastics.ppt

The International Association of Plastics DistributorsThe International Association of Plastics Distributors

The IAPD Plastics Primer, Module 4

Amorphous and Semi-CrystallineEngineering Thermoplastics

Materials, properties and applications.

Prepared by the IAPD Education Committee (Module 4)

Presented courtesy of Modern Plastics Inc.



IMIDE MATERIALS Key Characteristics: Very High Cost Per Pound Excellent Properties Above 400°F Excellent Electrical Properties Excellent Dimensional Stability Low Coefficient of Friction

Materials: PI

PAI PBI

IAPD THERMOPLASTICS RECTANGLE

AMORPHOUS HIGH PERFORMANCE PLASTICS

Key Characteristics High Cost

High Temperature High Strength & Good Stiffness

Good Chemical Resistance Transparency

Hot Water & Steam Resistance

Materials: Polysulfone

Polyetherimide Polyethersulfone Polyarylsulfone

SEMI-CRYSTALLINE HIGH PERFORMACE PLASTICS

Key Characteristics: High Cost

High Temperature High Strength

Good Electrical Properties Outstanding Chemical Resistance

Low Coefficient of Friction Good Toughness

Materials: PVDF PTFE

ECTFE FEP PFA PPS

PEEK

AMORPHOUS ENGINEERING PLASTICS

Key Characteristics: Moderate Cost

Moderate Temperature Resistance Moderate Strength

Good Impact Resistance Translucency

Good Dimensional Stability Good Optical Qualities

Materials: Polycarbonate Modified PPO Modified PPE

Thermoplastic Urethane

SEMI-CRYSTALLINE ENGINEERING PLASTICS



Good Chemical Resistance Good Bearing and Wear Properties

Low Coefficient of Friction Difficult to Bond

Materials: Nylon Acetal PET PBT

UHMW-PE

SEMI-CRYSTALLINE COMMODITY PLASTICS

Key Characteristics: Low Cost

Low Temperature Resistance Low Strength

Excellent Chemical Resistance Low Coefficient of Friction

Near Zero Moisture Absorption Very Good Electrical Properties

Good Toughness

Materials: Polyethylene

Polypropylene Polymetnylpentene(TPX)

AMORPHOUS COMMODITY PLASTICS


Low Temperature Resistance] Low Strength

Good Dimensional Stability Bond Well

Typically Transparent

Materials: Acrylic

Polystyrene ABS PVC

PETG CAB

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AMORPHOUS PLASTICS KEY CHARACTERISTICS: Soften Over a Broad Range Of Temperatures

Easy to Thermoform Tend to Be Transparent

Bond Well Using Adhesives and Solvents Prone To Stress Cracking Poor Fatigue Resistance

Stuctural Applications Only (Not for Bearing & Wear)

SEMI-CRYSTALLINE PLASTICS KEY CHARACTERISTICS: Sharp Melting Point

Difficult to Thermoform Tend to Be Opaque

Difficult To Bond Using Adhesives and Solvents Good Resistance To Stress Cracking

Good Fatigue Resistance Good For Bearing and Wear, As Well As Structural Applications



Amorphous Engineering ThermoplasticsKey Characteristics

• Moderate cost, strength and temperature resistance

• Good impact resistance

• Translucency

• Good dimensional stability

• Excellent optical qualities



Amorphous Engineering ThermoplasticsMaterials

• Polycarbonate (PC)• Polyphenylene Oxide (PPO)• Polyphenelyne Ether (PPE)• Thermoplastic Urethane (TPU)



Polycarbonate (PC)Strengths

Excellent clarity

Excellent toughness

Good heat resistance

Excellent electrical properties

Intrinsic flame-retardancy

Excellent strength



Polycarbonate (PC)Limitations

• Continual exposure to hot water causes gradual embitterment

• Most aromatic solvents, esters and ketones can cause crazing and cracking



Polycarbonate (PC)Applications

• Vandal resistant windows

• Machine guards

• Outdoor signs

• Sky lights

• Backboards

• Bike, roller blading protective wear



Modified Polyphenylene Oxide (Mod PPO) Modified Polyphenylene Ether (Mod PPE) Key Characteristics

• High dielectric strength

• Available in FDA compliant grades

• Less expensive than polycarbonate (PC)

• Good chemical resistance to strong acids, bases and water

• Wide range of processing

• Good creep resistance



Modified Polyphenylene Oxide (Mod PPO) Modified Polyphenylene Ether (Mod PPE) Applications

• Electrical housings in appliance, computers, business

equipment, etc.

• Water purification equipment parts

• Insulators

• Gears



Thermoplastic Polyurethane (TPU)Key Characteristics

• Wide range of service temperatures• Wide range of harness options• Excellent tear resistance• Excellent compression strength• Excellent resistance to non polar solvents• Excellent electrical properties• Excellent abrasion resistance• High tensile strength



Thermoplastic Polyurethane (TPU)Applications

• Impact resistant housings

• Valves

• Water filter caps

• Geophysical cable spacer



Semi-Crystalline Engineering Thermoplastics Key Characteristics

• Moderate cost, strength

• Moderate temperature resistance

• Good chemical resistance

• Good bearing and wear properties

• Low COF

• Difficult to bond



Semi-Crystalline Engineering Thermoplastics Materials

• Polyamide (PA) — Nylon• Polyoxymethylene (POM) — Acetal• Polyethylene terephthalate (PET)• Polybutylene terephthalate (PBT)• Ultra high molecular weight polyethylene

(UHMW-PE)



Nylon (PA) Strengths

• Good strength• Good toughness• Fair heat resistance• Good chemical resistance• Low COF



Nylon (PA) Limitations

Strong acidic environments Areas where moisture absorption is of

concern Areas experiencing high operating

temperatures



Nylon (PA) Applications

• Film• Automotive• Electrical/electronics• Consumer goods



Cast PA vs. Extruded PA• Extruded nylon can be produced in almost any grade • Cast nylon grades are limited to Type 6, Type 6 1/2 and some

Type 12 • Generally Nylon 6/6 and Nylon 6 (cast or extruded) are

interchangeable in most applications (physical property differences are minor)

• Nylon 6/6 is stronger and stiffer than Nylon 6, and has more resistance to compression

• Nylon 6 has better elongation values than Nylon 6/6, providing better ductility

• Cast Nylon can be produced in large profiles and custom shapes, and is generally less expensive than extruded grades



Acetal (POM)Strengths

• Good dimensional stability• Good wear resistance• Excellent strength• Excellent stiffness• Good rigidity• Low moisture absorption• Low COF



Acetal (POM)Limitations

• Centerline porosity in copolymers

• Using copolymer in hot water environments (boiling/steam)

• Strong acidic environments• Strong alkali environments• Areas experiencing high operating

temperatures



Acetal (POM)Applications

• Bearings• Bushings• Valve seats• Washers• Nozzles• Spools• Cams



Thermoplastic PolyestersKey Characteristics

Good range of mechanical properties

Good dimensional stability

Superior chemical resistance

Good electrical properties



Thermoplastic Polyesters Materials

• Polyethylene terephthalate (PET)• Polybutylene terephthalate (PBT)



Polyethylene Terephthalate (PET)Polybutylene Terephthalate (PBT)Key Characteristics

• High dimensional stability under heat• High stiffness and hardness• Good bearing strength• Good electrical properties• Good resistance to chemicals• Good stress-cracking resistance• Excellent flow characteristics



Thermoplastic PolyestersApplications

• Pump components• Automotive components• Food packaging components• Insulators



Thermoplastic PolyestersCaution!

Watch high temperature environments!

Use caution when recommending thermoplastic polyesters in applications requiring high temperature resistance, above 93-121oC/200-250oF.



Ultra High Molecular Weight PE (UHMW-PE)Strengths

• Highest abrasion resistance and impact strength of any plastic

• Very low COF• Excellent cryogenic (low temperature) material• Self-lubricating• FDA/USDA compliant



Ultra High Molecular Weight PE (UHMW-PE)Limitations

• Only good until 82oC/180oF• Not a self-supporting material• High cost for tooling for custom extrusion and

custom parts



Ultra High Molecular Weight PE (UHMW-PE)Applications

• Guides • Wear strips• Liners



IMIDE MATERIALS Key Characteristics: Very High Cost Per Pound Excellent Properties Above 400°F Excellent Electrical Properties Excellent Dimensional Stability Low Coefficient of Friction

Materials: PI

PAI PBI

IAPD THERMOPLASTICS RECTANGLE

AMORPHOUS HIGH PERFORMANCE PLASTICS

Key Characteristics High Cost

High Temperature High Strength & Good Stiffness

Good Chemical Resistance Transparency

Hot Water & Steam Resistance

Materials: Polysulfone

Polyetherimide Polyethersulfone Polyarylsulfone

SEMI-CRYSTALLINE HIGH PERFORMACE PLASTICS

Key Characteristics: High Cost

High Temperature High Strength

Good Electrical Properties Outstanding Chemical Resistance

Low Coefficient of Friction Good Toughness

Materials: PVDF PTFE

ECTFE FEP PFA PPS

PEEK

AMORPHOUS ENGINEERING PLASTICS



Good Impact Resistance Translucency

Good Dimensional Stability Good Optical Qualities

Materials: Polycarbonate Modified PPO Modified PPE

Thermoplastic Urethane

SEMI-CRYSTALLINE ENGINEERING PLASTICS



Good Chemical Resistance Good Bearing and Wear Properties

Low Coefficient of Friction Difficult to Bond

Materials: Nylon Acetal PET PBT

UHMW-PE

SEMI-CRYSTALLINE COMMODITY PLASTICS


Low Temperature Resistance Low Strength

Excellent Chemical Resistance Low Coefficient of Friction

Near Zero Moisture Absorption Very Good Electrical Properties

Good Toughness

Materials: Polyethylene

Polypropylene Polymetnylpentene(TPX)

AMORPHOUS COMMODITY PLASTICS


Low Temperature Resistance] Low Strength

Good Dimensional Stability Bond Well

Typically Transparent

Materials: Acrylic

Polystyrene ABS PVC

PETG CAB

SE

MI-C

RY

ST

AL

LIN

E P

LA

ST

ICS

AM

OR

PH

OU

S P

LA

ST

ICS

AMORPHOUS PLASTICS KEY CHARACTERISTICS: Soften Over a Broad Range Of Temperatures

Easy to Thermoform Tend to Be Transparent

Bond Well Using Adhesives and Solvents Prone To Stress Cracking Poor Fatigue Resistance

Stuctural Applications Only (Not for Bearing & Wear)

SEMI-CRYSTALLINE PLASTICS KEY CHARACTERISTICS: Sharp Melting Point

Difficult to Thermoform Tend to Be Opaque

Difficult To Bond Using Adhesives and Solvents Good Resistance To Stress Cracking

Good Fatigue Resistance Good For Bearing and Wear, As Well As Structural Applications

Documents

Amorphous and Semi-Crystalline plastics.ppt