+ All Categories
Home > Documents > Classes of Polymeric Materials

Classes of Polymeric Materials

Date post: 07-Feb-2016
Category:
Upload: kael
View: 58 times
Download: 0 times
Share this document with a friend
Description:
Classes of Polymeric Materials. Professor Joe Greene CSU, CHICO. Topics. Introduction Thermoplastics General Commercial plastics Thermosets General Commercial thermosets Elastomers General Commercial elastomers. Introduction. Polymeric materials can be either - PowerPoint PPT Presentation
Popular Tags:
143
1 Classes of Polymeric Materials Professor Joe Greene CSU, CHICO
Transcript
Page 1: Classes of Polymeric Materials

1

Classes of Polymeric Materials

Professor Joe Greene

CSU, CHICO

Page 2: Classes of Polymeric Materials

2

Topics• Introduction• Thermoplastics

– General

– Commercial plastics

• Thermosets– General

– Commercial thermosets

• Elastomers– General

– Commercial elastomers

Page 3: Classes of Polymeric Materials

3

Introduction• Polymeric materials can be either

– Thermoplastics, thermosets, and elastomers.– Each section is presented in appropriate groups

• Thermoplastics come in a variety of forms– Pellets, powder (1-100 microns), flake, chip, cube, dice, – Shipped in packages of choice

– Bags (50 lbs), drums (200 lbs), boxes, cartons, gaylords (1000 lb), – Tank-truck loads (15 tons), rail cars (40 – 80 tons)

• Bulk supplies are stored in silos and conveyed pneumatically

• Thermosets are supplied in powder or liquid form– Supplied in drums, tank-trucks, and railroad cars.

• Rubbers are supplied in bale form.

Page 4: Classes of Polymeric Materials

4

Commercial Thermoplastics • Olefins

– Unsaturated, aliphatic hydrocarbons made from ethylene gas– Ethylene is produced by cracking higher hydrocarbons of natural gas or

petroleum• LDPE commercialized in 1939 in high pressure process

• Branched, high pressure, and low density polyethylene• HDPE commercialized in 1957 in low pressure process

• Linear, low pressure, high density

• The higher the density the higher the crystallinity• Higher the crystallinity the higher the modulus, strength, chemical

resistance, • PE grades are classified according to melt index (viscosity) which is a

strong indicator of molecular weight.– Injection molding requires high flow, extrusion grade is highly elastic,

thermoforming grade requires high viscosity or consistency

Page 5: Classes of Polymeric Materials

5

Principal Olefin Monomers• Ethylene Propylene

• Butene-1 4-Methylpentene

C C

H H

H H

C C

C2H5 H

H H

C C

CH3 H

H H

C C

C5H6 H

H H

CH3

Page 6: Classes of Polymeric Materials

6

Several Olefin Polymers• Polyethylene Polypropylene

• Polyisobutene Polymethylpentene

C C

C5H6 H

H H

CH3

n

C C

H H

H H

n

C C

C2H5 H

H H

n

C C

CH3 H

H H

n

Page 7: Classes of Polymeric Materials

7

Polymers Derived from Ethylene Monomer

X Position Material Name AbbreviationH Polyethylene PECl Polyvinyl chloride PVCMethyl group Polypropylene PPBenzene ring Polystyrene PSCN Polyacrylonitrile PANOOCCH3 Polyvinyl acetate PvaCOH Polyvinyl alcohol PVACOOCH3 Polymethyl acrylate PMAF Polyvinyl fluoride PVF

Note:Methyl Group is:

|H – C – H | H

Benzene ring is:

X Position Y Position Material Name AbbreviationF F Polyvinylidene fluoride PVDFCl Cl Polyvinyl dichloride PVDCCH3 (Methyl group) CH3 Polyisobutylene PBCOOCH3 CH3 Polymethyl methacrylate PMMA

Page 8: Classes of Polymeric Materials

8

Addition Polymerization of PE• Polyethylene produced with low (Ziegler) or high pressure (ICI) • Polyethylene produced with linear or branched chains

OR

CCH

H

H

H

n

C C

H H

H H

C C

H H

H H

C C

H H

H H

C C

H H

H H

C C

H H

H H

……

C C

H H

H H

C C

H H

H H

C C

H

H H

C C

H H

H H

C C

H H

H H

……

Page 9: Classes of Polymeric Materials

9

Mechanical Properties of Polyethylene• Type 1: (Branched) Low Density of 0.910 - 0.925 g/cc

• Type 2: Medium Density of 0.926 - 0.940 g/cc

• Type 3: High Density of 0.941 - 0.959 g/cc

• Type 4: (Linear) High Density to ultra high density > 0.959

Mechanical PropertiesBranched LowDensity

MediumDensity

HighDensity

Linear High Density

Density 0.91- 0.925 0.926- 0.94 0.941-0.95 0.959-0.965

Crystallinity 30% to 50% 50% to 70% 70% to 80% 80% to 91%

MolecularWeight

10K to 30K 30K to 50K 50K to 250K 250K to 1.5M

TensileStrength, psi

600 - 2,300 1,200 - 3,000 3,100 - 5,500 5,000 – 6,000

TensileModulus, psi

25K – 41K 38K – 75 K 150K – 158K

150K – 158 K

TensileElongation, %

100% - 650% 100%- 965% 10% - 1300% 10% - 1300%

Impact Strengthft-lb/in

No break 1.0 – nobreak

0.4 – 4.0 0.4 – 4.0

Hardness, Shore D44 – D50 D50 – D60 D60 – D70 D66 – D73

Page 10: Classes of Polymeric Materials

10

Physical Properties of Polyethylene Physical Properties of polyethylene

Branched Low Density

Medium Density High Density

Linear High Density

Optical

Transparent to opaque

Transparent to opaque

Transparent to opaque

Transparent to opaque

Tmelt

98 – 115 C 122 – 124 C 130 – 137 C 130 –137 C

Tg -100 C -100 C -100 C -100 C H20 Absorption

Low < 0.01 Low < 0.01 Low < 0.01 Low < 0.01

Oxidation Resistance

Low, oxides readily

Low, oxides readily

Low, oxides readily Low, oxides readily

UV Resistance

Low, Crazes readily

Low, Crazes readily

Low, Crazes readily Low, Crazes readily

Solvent Resistance

Resistant below 60C

Resistant below 60C

Resistant below 60C Resistant below 60C

Alkaline Resistance

Resistant Resistant Resistant Resistant

Acid Resistance

Oxidizing Acids

Oxidizing Acids Oxidizing Acids Oxidizing Acids

Page 11: Classes of Polymeric Materials

11

Processing Properties of Polyethylene

Processing PropertiesBranched LowDensity

Medium Density HighDensity

Linear High Density

Tmelt 98 – 115 C 122 – 124 C 130 – 137 C 130 –137 C

Recommended TempRange (I:Injection, E:Extrusion)

I: 300F – 450FE: 250F – 450F

I: 300F – 450FE: 250F – 450F

I: 350F – 500FE: 350F – 525F

I: 350F – 500FE: 350F – 525F

Molding Pressure 5 – 15 psi 5 – 15 psi 12 – 15 psi 12– 15 psi

Mold (linear) shrinkage(in/in)

0.015 – 0.050 0.015 – 0.050 0.015 – 0.040 0.015 – 0.040

Page 12: Classes of Polymeric Materials

12

Special Low Versions of PolyethyleneProduced through catalyst selection and regulation of reactor conditions

• Very Low Density Polyethylene (VLDPE)• Densities between 0.890 and 0.915

• Applications include disposable gloves, shrink packages, vacuum cleaner hoses, tuning, bottles, shrink wrap, diaper film liners, and other health care products

• Linear Low Density Polyethylene (LLDPE)• Densities between 0.916 and 0.930

• Contains little if any branching by co-polymerizing ethylene at low pressures in presence of catalysts with small amounts of -olefin co-monomers (butene, hexene, octene) which play the role of uniform short branches along linear backbone.

• Properties include improved flex life, low warpage, improved stress-crack resistance, better impact, tear, or puncture versus conventional LDPE

• Applications include films for ice, trash, garment, and produce bags at thinner gage.

Page 13: Classes of Polymeric Materials

13

Special High Versions of PolyethyleneProduced through catalyst selection and regulation of reactor conditions

• Ultra High Molecular Weight Polyethylene (UHMWPE)

– Extremely high MW at least 10 times of HDPE (MW=3M to 6M)

– Process leads to linear molecules with HDPE

– Densities are 0.93 to 0.94 g/cc and Moderate cost– High MW leads to high degree of physical entanglements that

• Above Tmelt (130 C or 266F), the material behaves in a rubber-like molecule rather than fluid-like manner causing processing troubles, high viscosities

• Processed similar to PTFE (Teflon)

– Ram extrusion and compression molding are used.

Page 14: Classes of Polymeric Materials

14

Special High Versions of PolyethyleneProduced through catalyst selection and regulation of reactor conditions

• Ultra High Molecular Weight Polyethylene (UHMWPE)– Properties include outstanding properties like engineering plastic or

specialty resin• Chemical inertness is unmatched; environmental stress cracking

resistance and resistance to foods and physiological fluids,

• Outstanding wear or abrasion resistance, very low coefficient of friction, excellent toughness and impact resistance.

– Applications: • pump parts, seals, surgical implants, pen tips, and butcher-block cutting

surfaces. , chemical handling equipment, pen tips, prosthetic wear surfaces, gears

Page 15: Classes of Polymeric Materials

15

Special Forms of Polyethylene• Cross-linked PE (XLPE)

– Chemical cross-links improve chemical resistance and improve temperature properties.

– Cross-linked with addition of small amounts of organic peroxides • Dicumyl peroxide, etc.

– Crosslinks a small amount during processing and then sets up after flowing into mold.

– Used primarily with rotational molding– Extruded Products

• Films (shrink wrap film in particular)• Pipes• Electrical wire and cable insulation

Page 16: Classes of Polymeric Materials

16

Copolymers of Polyethylene• Ethylene-Vinyl Acetate (EVA)

– Repeating groups is ethylene with a vinyl acetate functional that reduces the regularity of the chain; thus the crystallinity and stiffness

– Part of the pendent group are highly polar which makes film with increased water vapor permeability, increased oil resistance and cling.

– Vinyl acetate reduces crystallinity and increases chemical reactivity because of high regions of polarity.

– Applications include flexible packaging, shrink wrap, auto bumper pads, flexible toys, and tubing with vinylacetate up to 50%

C C

H H

H H

C C

H OC = OC

H H

n m

Page 17: Classes of Polymeric Materials

17

Copolymers of Polyethylene• Ethylene-vinyl alcohol (EVOH)

• Contains equal amounts of two repeat units that act as– Barrier layers or as interlayers (tie layers) between incompatible materials due to strong

bonding of vinylalcohol repeat units.

• Ethylene-ethyl acrylate (EEA) Ethylene-methyl acrylate (EMA)• Properties range from rubbery to tough ethylene-like properties• Applications include hot melt adhesives, shrink wrap, produce bags, bag-in-box

products, and wire coating.• Produced by addition of methyl acrylate monomer (40% by weight) with ethylene gas

– reduces crystallinity and increases polarity

• Tough, thermally stable olefin with good rubber characteristics.• Applications include food packaging, disposable medical gloves, heat-sealable layers,

and coating for composite packaging

Page 18: Classes of Polymeric Materials

18

Copolymers of Polyethylene• Ethylene-carboxylic acid (EAA, EMAA)– Small amounts of acrylic acid (AA) or methacrylic acid (MAA) that feature carboxyl acid

groups (COOH) are notable adhesives, especially to polar substrates, including fillers and reinforcements

– Problems include tackiness and corrosive to metals and crosslinking nature

• Ionomers– Modified ethylene-methacrylic acid copolymers where some of the carboxyl acid groups are

converted into corresponding metallic salts (metal metacrylate), where the metals are sodium or zinc.

– Ionic bonds are formed between these cationic and the remaining anionic acid groups. Results in a quasi crosslinked polymer at low temperature and is reversible at high temperature

– Useful properties, e.g., adhesive and paints to metals (polarity), resistance to fats and oils, Flex, puncture, impact resistance

– Applications: golf balls, bowling pin covers, ski boot shells, films

Page 19: Classes of Polymeric Materials

19

Copolymers of Polyethylene• Ethylene-Propylene (EPM)

– Ethylene and propylene are copolymerized in random manner and causes a delay in the crystallization.

– Thus, the copolymer is rubbery at room temp because the Tg is between HDPE (-110C) and PP (-20C).

– Ethylene and propylene can be copolymerized with small amounts of a monomer containing 2 C=C double bonds (dienes)

– Results in a co-polymer, EPR, or thermoplastic rubber, TPR

C C

H H

H H

n

C C

CH3 H

H H

m

Page 20: Classes of Polymeric Materials

20

Mechanical Properties of PE Blends

Mechanical Properties of PE BlendsEthylene-vinylacetate

Ethylene-vinylalcohol

Ethylene-ethyl acrylate

Ethylene-methylacrylate

Density 0.922 – 0.943 1.14 – 1.19 0.93 0.942 – 0.945

TensileStrength, psi

2,200 – 4,000 8,520 – 11,600 1,600 – 2,100 1,650

TensileModulus, psi

7K – 29K 300 K – 385 K 4K – 7.5 K 12 K

TensileElongation, %

300% - 750% 180%- 280% 700% - 750% 740%

Impact Strengthft-lb/in

No break 1.0 – 1.7 No break

Hardness, Shore D17 – D45 D27 – D38

Page 21: Classes of Polymeric Materials

21

Processing Properties of PE Blends

Processing PropertiesEthylene-vinylacetate

Ethylene-vinylalcohol

Ethylene-ethylacrylate

Ethylene-methylacrylate

Tmelt 103 – 108 C 142 – 181 C 83 C

Recommended TempRange (C: Compression) (I:Injection, E:Extrusion)

C: 200-300FI: 300F – 430FE: 300F – 380F

I: 365F – 480FE: 365F – 480F

C: 200 – 300FI: 250F – 500F

E: 300F – 620F

Molding Pressure 1 – 20 psi 1 – 20 psi

Mold (linear) shrinkage(in/in)

0.007 – 0.035 0.015 – 0.035

Page 22: Classes of Polymeric Materials

22

Polypropylene History

• Prior to 1954 most attempts to produce plastics from polyolefins had little commercial success– PP invented in 1955 by Italian Scientist F.J. Natta by addition

reaction of propylene gas with a sterospecific catalyst titanium trichloride.

– Isotactic polypropylene was sterospecific (molecules are arranged in a definite order in space)

– PP is not prone to environmental stress-cracking like PE

• Polypropylene is similar in manufacturing method and in properties to PE

• Tg of PP = -25C versus Tg of PE of -100C

Page 23: Classes of Polymeric Materials

23

Chemical Structure• Propylene

• Isotactic- CH3 on one side of polymer chain (isolated). Commercial PP is 90% to 95% Isotactic

C C

CH3 H

H H

C C

CH3 H

H H

C C

CH3 H

H H

C C

CH3 H

H H

C C

CH3 H

H H

C C

CH3 H

H H

n

Page 24: Classes of Polymeric Materials

24

Polypropylene Stereostatic Arrangements •Atactic- CH3 in a random order (A- without; Tactic- order) Rubbery and of limited commercial value.

•Syndiotactic- CH3 in a alternating order (Syndio- ; Tactic- order)

C C

CH3 H

H H

C C

H H

H CH3

C C

CH3 H

H H

C C

H H

H CH3

C C

CH3 H

H H

C C

CH3 H

H H

C C

H H

H CH3

C C

H H

H CH3

C C

CH3 H

H H

C C

H H

H CH3

Page 25: Classes of Polymeric Materials

25

Addition Polymerization of PP• Polypropylene produced with low pressure process (Ziegler)

• Polypropylene produced with linear chains

• Polypropylene is similar in manufacturing method and in properties to PE

• Differences between PP and PE are– Density: PP = 0.90; PE = 0.941 to 0.965

– Melt Temperature: PP = 176 C; PE = 110 C

– Tg of PP = -25C versus Tg of PE of -100C– Service Temperature: PP has higher service temperature

– Hardness: PP is harder, more rigid, and higher brittle point

– Stress Cracking: PP is more resistant to environmental stress cracking

Page 26: Classes of Polymeric Materials

26

Advantages/Disadvatages of Polypropylene• Advantages

– Low Cost

– Excellent flexural strength

– Good impact strength

– Processable by all thermoplastic equipment

– Low coefficient of friction

– Excellent electrical insulation

– Good fatigue resistance

– Excellent moisture resistance

– Service Temperature to 126 C

– Very good chemical resistance

• Disadvantages– High thermal expansion

– UV degradation

– Poor weathering resistance

– Subject to attack by chlorinated solvents and aromatics

– Difficulty to bond or paint

– Oxidizes readily

– flammable

Page 27: Classes of Polymeric Materials

27

Mechanical Properties of Polypropylene Mechanical Properties of Polypropylene

Polypropylene LDPE(For Comparison)

HDPE(For Comparison)

Density 0.90 0.91- 0.925 0.959-0.965

Crystallinity 30% to 50% 30% to 50% 80% to 91%

Molecular Weight 200K to 600K 10K to 30K 250K to 1.5M

Molecular WeightDispersity MWD(Mw/Mn)

Range ofMWD forprocessing

Range of MWDfor processing

Range of MWDfor processing

Tensile Strength,psi

4,500 – 5,500 600 - 2,300 5,000 – 6,000

Tensile Modulus,psi

165K – 225K 25K – 41K 150K – 158 K

TensileElongation, %

100% - 600% 100% - 650% 10% - 1300%

Impact Strengthft-lb/in

0.4 – 1.2 No break 0.4 – 4.0

Hardness, Shore R80 - 102 D44 – D50 D66 – D73

Page 28: Classes of Polymeric Materials

28

Physical Properties of Polyethylene Physical Properties of Polypropylene

Polypropylene LDPE HDPEOptical Transparent to

opaqueTransparent toopaque

Transparent to opaque

Tmelt 175 C 98 – 115 C 130 –137 C

Tg -20 C -100 C -100 CH20Absorption

0.01 – 0.03 Low < 0.01 Low < 0.01

OxidationResistance

Low, oxidesreadily

Low, oxidesreadily

Low, oxides readily

UV Resistance Low, Crazesreadily

Low, Crazesreadily

Low, Crazes readily

SolventResistance

Resistantbelow 80C

Resistant below60C

Resistant below 60C

AlkalineResistance

Resistant Resistant Resistant

AcidResistance

OxidizingAcids

Oxidizing Acids Oxidizing Acids

Page 29: Classes of Polymeric Materials

29

Processing Properties of Polyethylene

Processing PropertiesPolypropylene LDPE HDPE

Tmelt 175 C 98 – 115 C 130 –137 C

Recommended TempRange (I:Injection, E:Extrusion)

I: 400F – 550FE: 400F – 500F

I: 300F – 450FE: 250F – 450F

I: 350F – 500FE: 350F – 525F

Molding Pressure 10 -20 psi 5 – 15 psi 12– 15 psi

Mold (linear) shrinkage(in/in)

0.010 – 0.025 0.015 – 0.050 0.015 – 0.040

Page 30: Classes of Polymeric Materials

30

Several Olefin Polymers• Polybutylene (PB)

– Based on butene-1 monomer

– Plus comonomers (small amt)

– Melt Point 125C similar to PE

– Tg, -25C is closer to PP

– Good creep & ESC resistance

– Good for pipe and film extrusions

C C

C2H5 H

H H

n

C C

HCH H

H H

H3C C CH3

n

• Polymethylpentene (PMP)– Trade name is TPX

– Crystallizes to high degree (60%)

– Highly transparent (90% transmis)

– Properties similar to PP

– Density is 0.83 g/cc, Tg =30C

– Stable to 200C, Tm=240C

– Creep and chemical resistance is good and low permeability.

– Electrical properties are excellent

– Process by injection & extrusion

– Good for lighting, packaging, trays, bags, coffee makers, wire covering, connectors, syringes.

– Poor ESC and UV

H

Page 31: Classes of Polymeric Materials

31

Polyolefin_Polybutylene • History

– PB invented in 1974 by Witco Chemical

– Ethyl side groups in a linear backbone

• Description

– Linear isotactic material

– Upon cooling the crystallinity is 30%

– Post-forming techniques can increase crystallinity to 55%

– Formed by conventional thermoplastic techniques

• Applications (primarily pipe and film areas)

– High performance films

– Tank liners and pipes

– Hot-melt adhesive

– Coextruded as moisture barrier and heat-sealable packages

C C

CH2 H

H H

CH3

Page 32: Classes of Polymeric Materials

32

Properties of Polybutylene

Mechanical Properties of PolybutylenePolybutylene Polypropylene LDPE

(For Comparison)HDPE(For Comparison)

Density 0.908 -.917 0.90 0.91- 0.925 0.959-0.965

Crystallinity 30% to 50% 30% to 50% 30% to 50% 80% to 91%

Tensile Strength,psi

4,000 4,500 – 5,500 600 - 2,300 5,000 – 6,000

Tensile Modulus,psi

10K – 40K 165K – 225K 25K – 41K 150K – 158 K

TensileElongation, %

300% - 400% 100% - 600% 100% - 650% 10% - 1300%

Impact Strengthft-lb/in

No break 0.4 – 1.2 No break 0.4 – 4.0

Hardness Shore D55 – D65 R80 - 102 D44 – D50 D66 – D73

Page 33: Classes of Polymeric Materials

33

Polyolefin_Polymethylpentene (PMP) • Description

– Crystallizes to 40%-60%

– Highly transparent with 90% transmission

– Formed by injection molding and blow molding

• Properties

– Low density of 0.83 g/cc; High transparency

– Mechanical properties comparable to polyolefins with higher temperature properties and higher creep properties.

– Low permeability to gasses and better chemical resistance

– Attacked by oxidizing agents and light hydrogen carbon solvents

– Attacked by UV and is quite flammable

• Applications

– Lighting elements (Diffusers, lenses reflectors), liquid level

– Food packaging containers, trays, and bags.

C C

CH2 H

H H

H3C-CH-CH3

Page 34: Classes of Polymeric Materials

34

Properties of Polymethylpentene Mechanical Properties of Polymethylpentene

Polymethyl-pentene

Polypropylene LDPE(For Comparison)

HDPE(For Comparison)

Density 0.83 0.90 0.91- 0.925 0.959-0.965

Crystallinity 40% to60% 30% to 50% 30% to 50% 80% to 91%

Tensile Strength,psi

4,000 – 5,000 4,500 – 5,500 600 - 2,300 5,000 – 6,000

Tensile Modulus,psi

160K – 200K 165K – 225K 25K – 41K 150K – 158 K

TensileElongation, %

100% - 400% 100% - 600% 100% - 650% 10% - 1300%

Impact Strengthft-lb/in

0.4 – 1.0 0.4 – 1.2 No break 0.4 – 4.0

Hardness R80 – R100 R80 - 102 D44 – D50 D66 – D73

Page 35: Classes of Polymeric Materials

35

PVC Background • Vinyl is a varied group- PVC, PVAc, PVOH, PVDC, PVB

– Polyvinyls were invented in 1835 by French chemist V. Regnault when he discovered a white residue could be synthesized from ethylene dichloride in an alcohol solution. (Sunlight was catalyst)

– PVC was patented in 1933 by BF Goodrich Company in a process that combined a plasticizer, tritolyl phosphate, with PVC compounds making it easily moldable and processed.

– PVC is the leading plastic in Europe and second to PE in the US.

– PVC is made by suspension process (82%), by mass polymerization (10% ), or by emulsion (8%)

– All PVC is produced by addition polymerization from the vinyl chloride monomer in a head-to-tail alignment.

– PVC is amorphous with partially crystalline (syndiotactic) due to structural irregularity increasing with the reaction temperature.

– PVC (rigid) decomposes at 212 F leading to dangerous HCl gas

Page 36: Classes of Polymeric Materials

36

PVC and Vinyl Products• Rigid-PVC

– Pipe for water delivery

– Pipe for structural yard and garden structures

• Plasticizer-PVC or Vinyl– Latex gloves

– Latex clothing

– Paints and Sealers

– Signs

Page 37: Classes of Polymeric Materials

37

PVC and PS Chemical Structure• Vinyl Groups (homopolymers produced by addition polymerization)

– PVC - poly vinylidene - polyvinylalcohol (PVOH)

chloride (PVDC)

– polyvinyl acetate (PVAc) - PolyStyrene (PS)

C C

H Cl

H H

n

C C

H Cl

H Cl

n

C C

H OCOCH3

H H

n

C C

H OH

H H

n

C C

H

H H

n

Page 38: Classes of Polymeric Materials

38

Mechanical Properties of Polyvinyls Mechanical Properties

PVC (rigid) PVC (Flexible) PVB PVDCDensity, g/cc 1.30-1.58 1.16-1.35 1.05 1.65-1.72

Tensile Strength,psi

6,000 - 7,500 1,500 -3,500 500 - 3,000 3,500 - 5,000

Tensile Modulus,psi

350K – 600K 160K –240K

TensileElongation, %

40% - 80% 200%-450% 150% - 450% 160% -240%

Impact Strengthft-lb/in

0.4 - 22 Range Range 0.4 - 1

Hardness Shore D65-85 Shore A50-100 M60-65

CLTE10-6 mm/mm/C

50 -100 70-250 190

HDT 264 psi 140 F -170F 130F -150F

Page 39: Classes of Polymeric Materials

39

Physical Properties of Polyvinyls PVC (rigid) PVC (Flexible) PVB PVDC

Optical Transparent Transparent Transparent Transparent

Tmelt 75 – 105 C 75 – 105 C 49 172C

Tg 75 -105C 75-105C 49 -15C

H20Absorption

0.04-0.4% (24h) 0.15-0.75% (24h) 0.09-0.16% (24h) 0.1% (24h)

OxidationResistance

good good good good

UV Resistance Poor Poor Poor good

SolventResistance

Soluble inAcetone, and

Cyclohexanol.Partially in

Toluene

Soluble inAcetone, and

Cyclohexanol.Partially in

Toluene

Dissolved in ketonesand esters

good

AlkalineResistance

Excellent Excellent Excellent good

AcidResistance

good good good good

Cost $/lb $0.27 $0.27 $ $1.62

Page 40: Classes of Polymeric Materials

40

Processing Properties of Polyvinyls

PVC (rigid) PVC (Flexible) PVB PVDCTmelt 75 – 105 C 75 – 105 C 49 172C

Recommended TempRange (I:Injection, E:Extrusion,C: Compression)

I: 300F – 415FC: 285F-400F

I: 320F – 385FC: 285F - 350F

I: 250F – 340FC: 280F-320F

I: 300F – 400FC: 260F-350FE: 300F-400F

Molding Pressure 10-40 kpsi 8-25 kpsi 0.5-3kpsi 5 - 30 kpsi

Mold (linear) shrinkage(in/in)

0.002 – 0.006 0.010 – 0.050 0.005 - 0.025

Page 41: Classes of Polymeric Materials

41

Vinylchloride Co-Polymers• Chlorinated PVC (CPVC)

– Possible to chemically modify PVC by substituting Cl for H– Cl content can be raised from 56.8% in PVC to 62%-72%– CPVC has improved chemical and temperature resistance that can be used for

pipe and hot water applications, even boiling water.

• Vinylchloride-vinylacetate (PVC-VAC)– Internally plasticizing PVC with 3% to 30% vinyl acetate– Impact properties and processing ease are improved for

• Floor coverings, phonograph records.

• Polyalloys– Improves impact resistance of rigid PVC by blending with elastomers, e.g.,

EVA, Nitrile rubber (NBR), Chloronated PE.– Blend PVC with PMMA and SAN for better transparency– Blend PVC with ABS for improved combustion resistance

Page 42: Classes of Polymeric Materials

42

Vinylchloride Co-Polymers• Polyvinylidenechloride (PVDC)

– Homopolymer can crystallize. Tg = -18C, Tm = 190C

• Decomposition temperature is slightly above melt temperature of abut 200C

• PVDC has outstanding barrier properties for O2, CO2, and H2O.

• Copolymerized with 10-15% vinyl chloride to create Saran Wrap.

• Copolymerize with acrlonitrile and acrylate esters up to 50%.

• Coplymerization reduces crystallinity to 35-45% and the Tmelt ot 175C

• Polyvinyl acetate (PVAC)– Not used as a plastic

• Noncrystallizing

• Low Tg = 30C, it is– It is best as a major ingredient in adhesives and paint, Elmers Glue

– Vinylacetate repeat units form the minor component in imporant copolymers with vinylchloride (PVC-PVAC) and ethylene (EVA)

C C

H Cl

H Cl

n

C C

H OCOCH3

H H

n

Page 43: Classes of Polymeric Materials

43

Vinylchloride Co-Polymers• Polyvinylalcohol (PVAL or PVOH)

– Homopolymer is very polar can crystallize– Water soluable. Tg = 80C, Tm = 240C– Random copolymer that is derived from PVAC– Used as a release film for reinforced plastics or barrier film.

• Polyvinylbutyral (PVB)– Random copolymer (PVB-PVAL)

• containing 10-15% VAL• Low Tg = 50C

– Used in plasticized form as adhesive interlayer• For windshield safety glass (Saflex from Monsanto)• Powder is extruded into sheet and then placed between two layers of glass

– Requires• Toughness, transparency, weatherability, and adhesion to glass.

C C

H OH

H H

n

C C

H CH2

H H

nCH2CH3

Page 44: Classes of Polymeric Materials

44

PS Background • PS is one of the oldest known vinyl compounds

– PS was produced in 1851 by French chemist M. Berthelot by passing benzene and ethylene through a red-hot-tube (basis for today)

– Amorphous polymer made from addition polymerization of styrene– Homopolymer (crystal): (2.7 M metric tons in ’94) GPPS (General Purpose PS)

• Clear and colorless with excellent optical properties and high stiffness.• It is brittle until biaxially oriented when it becomes flexible and durable.

– Graft copolymer or blend with elastomers- High Impact Polystyrene (HIPS):

• Tough, white or clear in color, and easily extruded or molded.• Properties are dependent upon the elastomer %, but are grouped into

– medium impact (Izod<1.5 ft-lb), high impact (Izod between 1.5 to 2.4 ft-lb) and super-high impact (Izod between 2.6 and 5 ft-lb)

– Copolymers include SAN (poly styrene-acrylonitrile), SMA (maleic anhydride), SBS (butadiene), styrene and acrylic copolymers.

– Expandable PS (EPS) is very popular for cups and insulation foam.

• EPS is made with blowing agents, such as pentane and isopentane. • The properties are dependent upon cell size and cell size distribution

Page 45: Classes of Polymeric Materials

45

Polystyrene Polymers

• Poly-para-methyl-styrene (PPMS)– Similar to PS (Tg=100C) with a slightly higher Tg=110C

– Low cost alternative to PS in homo and co-polymers

• Poly-alpha-methyl-styrene (PAMS)– High Tg =160C and better Temp resistance

– Not much commercial importance by itself

– Has significant use in copolymers

• Rubber-toughened impact polystyrene (HIPS)– Random copolymerization with small fraction of elastomer type repeat units.

Lowers Tg

– Block copolymerization of elastomeric component is more expensive, but keeps Tg same as PS

C C

H

H H

nCH3

C C

H

H

n

CH3

Page 46: Classes of Polymeric Materials

46

PSB, SAN, ABS Chemical Structure• PSB (copolymer -addition) * Styrene- acrylonitrile (SAN)

• ABS acrylonitrile butadiene styrene (Terpolymer- addition)

C C

H

H H

km

C C

H C:::N

H H

n

C C

CH3 CH3

H H

C C

H

H H

k m

C C

CH3CH3

H H

C C

H

H H

k

C C

H C:::N

H H

n

Page 47: Classes of Polymeric Materials

47

Polystyrene Co-Polymers• Styrene-Butadiene (PSB)

– Tg= % of each PS (100C) and Butadiene (-80C)

• Example, 50% PS and 50% B, Tg=10C– Easy to copolymerize and can be rubbery (butadiene-dominant) or plastic like

(styrene-like), out 70% of the PSB is styrene dominant– Random (styrene dominant) copolymers have been used in emulsion (latex) form to

produce coatings (paints).– Block copolymers are commercial butadiene styrene-plastics

• Styrene Acrylonitrile (SAN)– Random copolymer of 30% polyacrylonitrile repeat units yields

• Increased Temp performance and transparent, ease to process• Resistant to food and body oils

– Used for transparent medical products, houseware care items– Polyalloys (blends) with polysulphone

Page 48: Classes of Polymeric Materials

48

Polystyrene Co-Polymers• Acrylonitrile Butadiene Styrene (ABS)

– First introduced in the late 1940s as replacement for rubber.– Terpolymer: Three repeat units vary according to grade (20%A, 20%B, 60%S)

• Acrylonitrile for chemical and temperature resistance• Butadiene for impact resistance; Styrene for cost and processability• Graft polymerization techniques are used to produce ABS

– Very versatile applications that are injection molded and extruded• Rigid pipes and fittings, thermoformed refrigerator door liners, Legos toys• Small boat hulls, telephone and computer housings

• Family of materials that vary from high gloss to low matte finish, and from low to high impact resistance.• Additives enable ABS grades that are flame retardant, transparent, high heat-resistance, foamable, or UV-

stabilized

• ABS-based polyalloys (blends)– PVC/ABS for flame resistance – TPU/ABS for polyurethane; PSU/ABS for polysulphone– PC/ABS for temperature and impact resistance (Saturn door)

• .

Page 49: Classes of Polymeric Materials

49

Mechanical Properties of PS, ABS, SAN

Mechanical PropertiesPS ABS SAN

Density, g/cc 1.04 1.16-1.21 1.07

Tensile Strength,psi

5,000 - 7,200 3,300 - 8,000 10,000 -12,000

Tensile Modulus,psi

330K-475K 320K-400K 475K-560K

TensileElongation, %

1.2% - 2.5% 1.5%-25% 2%-3%

Impact Strengthft-lb/in

0.35-0.45 1.4-12 0.4-0.6

Hardness M60-75 R100-120 R83, M80

CLTE10-6 mm/mm/C

50 -83 65- 95 65-68

HDT 264 psi 169F - 202F 190F - 225F 214F - 220F

C C

H

H H

n

Tg =100C

Page 50: Classes of Polymeric Materials

50

Physical Properties of PS, ABS, SAN PS ABS SAN

Optical

Transparent Transparent Transparent

Tmelt

100 C 125C 120C

Tg 70 -115C 110 -125C 120C

H20 Absorption

0.01-0.03% (24h)

0.2-0.6% (24h)

0.15-0.25% (24h)

Oxidation Resistance

good good good

UV Resistance

fair fair fair

Solvent Resistance

Soluble in Acetone, Benzene,

Toluene and Methylene dichloride

Soluble in Toluene and

Ethylene dichloride, Partially in Benzene

Dissolved in ketones and esters

Alkaline Resistance

Excellent Excellent Poor: attacked by oxidizing agents

Acid Resistance

Poor: attacked by oxidizing agents

Poor: attacked by oxidizing agents

good

Cost $/lb

$0.41 $0.90 $0.87

Page 51: Classes of Polymeric Materials

51

Processing Properties of PS, ABS, SAN

PS ABS SANTmelt 100 C 125C 120C

Recommended TempRange (I:Injection, E:Extrusion)

I: 350F – 500FE: 350F- 500FC: 300F - 400F

I: 380F – 500FC: 350F - 500F

I: 360F – 550FE: 360F -450FC:300F - 400F

Molding Pressure 5 - 20 kpsi 8-25 kpsi 5-20 kpsi

Mold (linear) shrinkage(in/in)

0.004 – 0.007 0.004 – 0.008 0.003 – 0.005

Page 52: Classes of Polymeric Materials

52

Acrylic and Cellulosic Background • Acrylics (1901)

– Includes acrylic and methacrylic esters, acids, and derivatives.

– Used singularly or in combination with other polymers to produce products ranging from soft, flexible elastomers to hard, stiff thermoplastics and thermosets.

• Cellulosics (1883)– Cellulose nitrate was first developed in the 1880s.

– First uses were billiard balls, combs, and photographic film.

– Cellulose acetate was developed in 1927 reduced the limitations of flammability, and solvent requirement.

– In 1923, CA became the first material to be injection molded.

– Cellulose acetate butyrate (CAB) in1938 and Cellulose acetate propionate (CAP) in 1945 found applications for hair brushes, toothbrushes, combs, cosmetic cases, hand tool handles, steering wheels, knobs, armrests, speakers, grilles, etc.

Page 53: Classes of Polymeric Materials

53

Acrylics Chemical Structure

• Acrylics- Basic formula - Polymethyl acrylate

• Polymethyl methacrylate -AcrylateStyreneAcrylonitrile (ASA)

C C

H COOR2

H R1

n

C C

H COOCH3

H H

n

C C

H COOCH3

H CH3

n

C C

H C:::N

H H

k

C C

H

H H

m

C C

H COOH

H H

n

Page 54: Classes of Polymeric Materials

54

Applications for PC and Acrylics

• PC (high impact strength, transparency, excellent creep and

temperature) – lenses, films, windshields, light fixtures, containers, appliance

components and tool housings

– hot dish handles, coffee pots, popcorn popper lids, hair dryers.

– Pump impellers, safety helmets, beverage dispensers, trays, signs

– aircraft parts, films, cameras, packaging

• Acrylics– Optical applications, outdoor advertising signs, aircraft windshields,

cockpit covers, bubble bodies for helicopters

– Plexiglass, window frames, (glass filled): tubs, counters, vanities

Page 55: Classes of Polymeric Materials

55

Mechanical Properties of Acrylic, PC, PC/ABS

Mechanical PropertiesAcrylic PC ABS PC/ABS

Density, g/cc 1.16- 1.19 1.2 1.16-1.21 1.07 - 1.15

Tensile Strength,psi

5,000 - 9,000 9,500 3,300 - 8,000 5,800 - 9,300

Tensile Modulus,psi

200K – 500K 350 K 320K-400K 350K -450K

TensileElongation, %

20 - 70% 110% 1.5%-25% 50%-60%

Impact Strengthft-lb/in

0.65 -2.5 16 1.4-12 6.4 - 11

Hardness M38-M68 M70 R100-120 R95 -R120

CLTE10-6 mm/mm/C

48 - 80 68 65- 95 67

HDT 264 psi 165-209F 270 190F - 225F 225F

Page 56: Classes of Polymeric Materials

56

Physical Properties of Acrylic, PC, PC/ABS Acrylic PC ABS PC/ABS

Optical Transparent Transparent Transparent Transparent

Tmelt 105C 150C 125C 135C

Tg 75 -105C 110 -125C 110 -125C 120C

H20Absorption

0.01-0.03% (24h) 0.2-0.6% (24h) 0.2-0.6% (24h) 0.15-0.25% (24h)

OxidationResistance

good good good good

UV Resistance fair fair fair fair

SolventResistance

Soluble inAcetone, Benzene,Toluene, ethylene

dichloride

Partially Soluble inAcetone, Benzene,

Toluene. Dissolves inhot benzene-toluene

Soluble in Tolueneand Ethylene

dichloride, Partially inBenzene

Soluble in Tolueneand Ethylene

dichloride, Partially inBenzene

AlkalineResistance

Excellent Excellent Excellent Poor: attacked byoxidizing agents

AcidResistance

Poor: attacked byoxidizing agents

Poor: attacked byoxidizing agents

Poor: attacked byoxidizing agents

good

Cost $/lb $0.41 $0.90 $0.90 $0.87

Page 57: Classes of Polymeric Materials

57

Advantages• PC

– High impact strength, excellent creep resistance, transparent

– Very good dimensional stability and continuous temp over 120 C

• Acrylics– Optical clarity, weatherability, electrical properties, rigid, high gloss

Disadvantages• PC

– High processing temp,UV degradation

– Poor resistance to alkalines and subject to solvent cracking

• Acrylics– Poor solvent resistance, stress cracking, combustibility, Use T 93C

Page 58: Classes of Polymeric Materials

58

Polyamide History • PA is considered the first engineering thermoplastic• PA is one of many heterochain thermoplastics, which has atoms other

than C in the chain.• PA invented in 1928 by Wallace Carothers, DuPont, in search of a

“super polyester” fiber with molecular weights greater than 10,000. First commercial nylon in 1938.

• PA was created when a condensation reaction occurred between amino acids, dibasic acids, and diamines.

• Nylons are described by a numbering system which indicates the number of carbon atoms in the monomer chains– Amino acid polymers are designated by a single number, as nylon 6

– Diamines and dibasic acids are designated with 2 numbers, the first representing the diamine and the second indicating the adipic acid, as in nylon 6,6 or nylon 6,10 with sebacic acid.

Page 59: Classes of Polymeric Materials

59

Chemistry & Chemical Structurelinear polyamides• Thermoplastic nylons have amide (CONH) repeating link

• Nylon 6,6 - poly-hexamethylene-diamine (linear)NH2(CH2)6NH2 + COOH(CH2)4COOH

hexamethylene diamine + Adipic Acid

n[NH2(CH2)6NH . CO (CH2)4COOH ] + (heat)

nylon salt

[NH2(CH2)6NH . CO (CH2)4CO ]n + nH2O

Nylon 6,6 polymer chain

• Nylon 6 - polycaprolactam (linear)[NH(CH2)5CO ]n

Page 60: Classes of Polymeric Materials

60

Chemistry & Chemical Structurelinear polyamides

• Nylon 6, 10 - polyhexamethylenesebacamide (linear)

[NH2(CH2)6NH . CO (CH2)8CO]n

• Nylon 11 - Poly(11-amino-undecanoic-amide (linear)[NH(CH2)10CO ]n

• Nylon 12 - Poly(11-amino-undecanoic-amide (linear) [NH(CH2)11CO ]n

• Other Nylons– Nylon 8, 9, 46, and copolymers from other diamines and acids

Page 61: Classes of Polymeric Materials

61

Chemistry & Chemical StructureAromatic polyamides (aramids)• PMPI - poly m-phenylene isophthalamide (LCP fiber)

[ -NHCO - NHCO ]n

• PPPT - poly p-phenylene terephthalamide (LCP fiber)

[ -NHCO - NHCO ]n

• Nomax PMPI - – first commercial aramid fiber for electrical insulation. LCP fibers feature straight chain crystals

• Kevlar 29 PPPT- – textile fiber for tire cord, ropes, cables etc.

• Kevlar 49 PPPT - reinforcing fiber for thermosetting resins

Page 62: Classes of Polymeric Materials

62

Chemistry & Chemical StructureTransparent polyamides

• PA- (6,3,T)

[CH2C3H6C2H4-NHCO - NHCO ]n

• PA - (6,T)

[(CH2) 6NHCO - NHCO ]n

• Transparent polyamides are commercially available • Reduced crystallization due to introduction of side groups

Page 63: Classes of Polymeric Materials

63

Applications for Polyamides

• Fiber applications– 50% into tire cords (nylon 6 and nylon 6,6)

– rope, thread, cord,belts, and filter cloths.

– Monofilaments- brushes, sports equipment, and bristles (nylon 6,10)

• Plastics applications– bearings, gears, cams

– rollers, slides, door latches, thread guides

– clothing, light tents, shower curtains, umbrellas

– electrical wire jackets (nylon 11)

• Adhesive applications– hot melt or solution type

– thermoset reacting with epoxy or phenolic resins

– flexible adhesives for bread wrappers, dried soup packets, bookbindings

Page 64: Classes of Polymeric Materials

64

Mechanical Properties of Polyamides Mechanical Properties of Nylon

Nylon 6 Nylon 6,6 Nylon 6,10 Nylon 6,12Density, g/cc 1.13-1.15 1.13-1.15 1.09 1.06-1.10

Crystallinity 30-% - 50% 30-% - 50% 30-% - 50% 30-% - 50%

Molecular Weight 10,000–30,000 10,000–30,000 10,000–30,000 10,000–30,000

Tensile Strength,psi

6,000 – 24,000 14,000 8,500 – 8,600 6,500 – 8,800

Tensile Modulus,psi

300K 230K – 550K 250 K 220 - 290 K

TensileElongation, %

30% - 100% 15%-80% 70% 150%

Impact Strengthft-lb/in

0.6 – 2.2 0.55 – 1.0 1.2 1.0 –1.9

Hardness R80 - 102 R120 R111 M78

Page 65: Classes of Polymeric Materials

65

Physical Properties of Polyamide Nylon 6 Nylon 6,6 Nylon 6,10 Nylon 6,12

Optical Translucent toopaque

Translucent toopaque

Translucent to opaque Translucent to opaque

Tmelt 210C -220 C 255C – 265C 220 C 195 -219 C

Tg

H20Absorption

1.3-1.9% (24h)8.5-10 (Max)

1.0-2.8% (24h)8.5% (Max)

1.4% (24h)3.3% (Max)

0.4 – 1.0% (24h)2.5 –3 % (Max)

OxidationResistance

good good good good

UV Resistance Poor Poor Poor Poor

SolventResistance

Dissolved byphenol &

formic acid

Dissolved byphenol & formic

acid

Dissolved by phenol &formic acid

Dissolved by phenol &formic acid

AlkalineResistance

Resistant Resistant Resistant Resistant

AcidResistance

Poor Poor Poor Poor

Cost $/lb $1.30 $1.30 $3.00 $3.10

Page 66: Classes of Polymeric Materials

66

Advantages Disadvantages of Polyamide• Advantages

– Tough, strong, impact resistant– Low coefficient of friction– Abrasion resistance– High temperature resistance– Processable by thermopalstic methods– Good solvent resistance– Resistant to bases

• Disadvantages– High moisture absorption with dimensional instability

• loss of up to 30 % of tensile strength and 50% of tensile modulus– Subject to attack by strong acids and oxidizing agents– Requires UV stabilization– High shrinkage in molded sections– Electrical and mechanical properties influenced by moisture content– Dissolved by phenols

Page 67: Classes of Polymeric Materials

67

Additives and Reinforcements to PA• Additives- antioxidants, UV stabilizers, colorants, lubricants• Fillers

– Talc– Calcium carbonate

• Reinforcements– Glass fiber- short fiber (1/8” or long fiber 1/4”)– Mineral fiber (wolastonite)– carbon fibers– graphite fibers– metallic flakes– steel fibers

Page 68: Classes of Polymeric Materials

68

Properties of Reinforced Nylon

Nylon 6,6 Nylon 6,6 with30% short glass

Nylon 6,6 with30% long glass

Nylon 6,6 with30% carbon fiber

Density, g/cc 1.13-1.15 1.4 1.4 1.06-1.10

Crystallinity 30-% - 50% 30-% - 50% 30-% - 50% 30-% - 50%

Molecular Weight 10,000–30,000 30,000 10,000–30,000 10,000–30,000

Tensile Strength,psi

14,000 28,000 28,000 32,000

Tensile Modulus,psi

230K – 550K 1,300K 1,400 K 3,300 K

TensileElongation, %

15%-80% 3% 3% 4%

Impact Strengthft-lb/in

0.55 – 1.0 1.6-4.5 4.0 1.5

Hardness R120 R120 E60 R120

Moisture % 1.0-2.8% (24h)8.5% (Max)

0.7-1.1 (24h)5.5-6.5 (Max)

0.9 (24h)5.5-6.5 (Max)

0.7 (24h)5 (Max)

Cost $/lb $1.40 $1.70 $2.00 $2.70

Page 69: Classes of Polymeric Materials

69

Other Heterochain Polymers

• Polyimide– Developed by Du Pont in 1962

– Obtained from a condensation polymerization of aromatic diamine and an aromatic dianhydride

– Characterized as Linear thermoplastics that are difficult to process

– Many polyimides do not melt but are fabricated by machining

– Molding can occur if enough time for flow is allowed for T>Tg

• Advantages– High temperature service (up to 700C)

– Excellent barrier, electrical properties, solvent and wear resistance

– Good adhesion and ezpecially suited for composite fabrication

ONCO

NCO

CO CO

Page 70: Classes of Polymeric Materials

70

Other Heterochain Polymers• Polyimide Disadvantages

– Difficulty to fabricate and requires venting of volatiles– Hydroscopic and Subject to attacks by alkalines– Comparatively high cost

• Applications• Aerospace, electronics, and nuclear uses (versus flurocarbons)

• Office and industrial equipment; Laminates, dielectrics, and coatings

• Valve seats, gaskets, piston rings, thrust washers, and bushings

• Polyamide-imide• Amorphous member of imide family, marketed in 1972 (Torlon), and

used in aerospace applications such as jet engine components

• Contains aromatic rings and nitrogen linkage

• Advantages include: High temperature properties (500F), low coefficient of friction, and dimensional stability.

Page 71: Classes of Polymeric Materials

71

Other Heterochain Polymers• Polyacetal or Polyoxymethylene (POM)

• Polymerized from formaldehyde gas• First commercialized in 1960 by Du Pont• Similar in properties to Nylon and used for plumbing fixtures, pump impellers,

conveyor belts, aerosol stem valves, VCR tape housings

• Advantages• Easy to fabricate, has glossy molded surfaces, provide superior fatigue endurance,

creep resistance, stiffness, and water resistance.• Among the strongest and stiffest thermoplastics.• Resistant to most chemicals, stains, and organic solvents

• Disadvantages• Poor resistance to acids and bases and difficult to bond• Subject to UV degradation and is flammable• Toxic fumes released upon degradation

H-O-(CH2-O-CH2-O)NH:R

Page 72: Classes of Polymeric Materials

72

Mechanical Properties Nylon 6 Acetal Polyimid Polyamide-imide

Density, g/cc 1.13-1.15 1.42 1.43 1.41

Crystallinity 30-% - 50%

Molecular Weight 10,000–30,000

Tensile Strength,psi

6,000 – 24,000 10,000 10,000 26,830

Tensile Modulus,psi

300K 520K

TensileElongation, %

30% - 100% 40% - 75%

Impact Strengthft-lb/in

0.6 – 2.2 0.07 0.9 2.5

Hardness R80 - 102 R120 E50 E78

Tmelt 210 - 220 C 175-181 C Tg=275CMoisture24 hrmax

1.3 - 1.9%8.5 - 10%

0.25 to 0.40%1.41%

0.32% .28%

Optical Translucent toopaque

Translucent toopaque

opaque Transparent toopaque

Page 73: Classes of Polymeric Materials

73

Polyester History • 1929 W. H. Carothers suggested classification of polymers into two

groups, condensation and addition polymers.

• Carothers was not successful in developing polyester fibers from linear aliphatic polyesters due to low melting point and high solubility. No commercial polymer is based on these.

• p-phenylene group is added for stiffening and leads to polymers with high melting points and good fiber-forming properties, e.g., PET.

• Polymers used for films and for fibers

• Polyesters is one of many heterochain thermoplastics, which has atoms other than C in the chain.

• Polyesters includes unsaturated (thermosets), saturated and aromatic thermoplastic polyesters.

Page 74: Classes of Polymeric Materials

74

Chemistry & Chemical Structurelinear polyesters (versus branched)

• Thermoplastic polyesters have ester(-C-O) repeating link• Polyester (linear) PET and PBT

C6H4(COOH)2 + (CH2)2(OH)2 -[(CH2)2 -O- C - C-O]-

terephthalic acid + ethylene glycol Polyethylene terephthalate (PET)

C6H4(COOH)2 + (CH2)4(OH)2 -[(CH2)4 -O- C - C-O]-

terephthalic acid + butylene glycol Polybutylene terephthalate (PBT)

O

O O

O O

Page 75: Classes of Polymeric Materials

75

Chemistry & Chemical Structurelinear polyesters (versus branched)

• Wholly aromatic copolyesters (LCP)– High melting sintered: Oxybenzoyl (does not melt below its decomposition temperature. Must be compression molded)– Injection moldable grades: Xydar and Vectra

– Xydar (Amoco Performance Products)• terephthalic acid, p,p’- dihydroxybiphenyl, and p-hydroxybenzoic acid

– Grade 1: HDT of 610F– Grade 2: HDT of 480 F

– Vectra (Hoechst Celanese Corp.)• para-hydroxybenzoic acid and hydroxynaphtholic acid

– Contains rigid chains of long, flat monomer units which are thought to undergo parallel ordering in the melt and form tightly packed fibrous chains in molded parts.

Page 76: Classes of Polymeric Materials

76

PET Chemical Structure and Applications• The flexible, but short, (CH2)2 groups tend to leave the chains

relatively stiff and PET is notes for its very slow crystallization. If cooled rapidly from the melt to a Temp below Tg, PET solidifies in amorphous form.

• If PET is reheated above Tg, crystallizaiton takes place to up to 30%.• In many applications PET is first pre-shaped in amorphous state and

then given a uniaxial (fibers or tapes) or biaxial (film or containers) crystalline orientation.

• During Injection Molding PET can yield amorphous transparent objects (Cold mold) or crystalline opaques objects (hot mold)

Page 77: Classes of Polymeric Materials

77

PBT Chemical Structure and Applications

• The longer, more flexible (CH2)4 groups allow for more rapid crystallization than PET.

• PBT is not as conveniently oriented as PET and is normally injection molded.

• PBT has a sharp melting transition with a rather low melt viscosity.

• PBT has rapid crystallization and high degree of crystallization causing warpage concerns

Page 78: Classes of Polymeric Materials

78

Thermoplastic Aromatic Copolyesters• Polyarylesters

– Repeat units feature only aromatic-type groups (phenyl or aryl groups) between ester linkages.

– Called wholly aromatic polyesters– Based on a combination of suitable chemicals

• p-hydroxybenzoic acid• terephthalic acid• isophthalic acid,• bisphenol-A

– Properties correspond to a very stiff and regular chain with high crystallinity and high temperature stability

– Applications include bearings, high temperature sensors, aerospace applications– Processed in injection molding and compression molding– Most thermoplastic LCP appear to be aromatic copolyesters

Page 79: Classes of Polymeric Materials

79

Applications for Polyesters (PET)• Blow molded bottles

• 100% of 2-liter beverage containers and liquid products

• Fiber applications • 25% of market in tire cords, rope, thread, cord, belts, filter cloths.

• Monofilaments- brushes, sports equipment, clothing, carpet, bristles

• Tape form- uniaxially oriented tape form for strapping

• Film and sheets• photographic and x-ray films; biaxial sheet for food packages

• Molded applications- Reinforced PET [Rynite, Valox, Impet]• luggage racks, grille-opening panels, functional housings such as windshield

wiper motors, blade supports, and end bells

• sensors, lamp sockets, relays, switches, ballasts, terminal blocks

• Appliances and furniture• oven and appliance handles, coil forms for microwaves

• panel pedestal bases, seat pans, chair arms, and casters

Page 80: Classes of Polymeric Materials

80

Applications for Polyesters (PBT and LCP)

• PBT - 30 M lbs in 1988• Molded applications (PBT) [Valox, Xenoy, Vandar, Pocan]

– distributers, door panels, fenders, bumper fascias– automotive cables, connectors, terminal blocks, fuse holders and motor

parts, distributor caps, door and window hardware

• Extruded applications– extrusion-coat wire– extruded forms and sheet produced with some difficulty

• Electronic Devices (LCP) [26 M lbs] [Terylene, Dacron, Kodel]

– fuses, oxygen and transmission sensors– chemical process equipment and sensors– coil

Page 81: Classes of Polymeric Materials

81

Mechanical Properties of Polyesters

Mechanical Properties of polyesterPET PBT LCP Polyester

Density, g/cc 1.29-1.40 1.30 - 1.38 1.35 - 1.40

Crystallinity 10% - 30% 60% >80%

Molecular Weight

Tensile Strength,psi

7,000 – 10,500 8,200 16,000 – 27,000

Tensile Modulus,psi

400K - 600K 280K – 435K 1,400K - 2,800K

TensileElongation, %

30% - 300% 50%-300% 1.3%-4.5%

Impact Strengthft-lb/in

0.25 - 0.70 0.7 - 1.0 2.4 - 10

CLTE10-6 in/in/C

65 60-95 25-30

HDT 264 psi 70F -100F 122F - 185F 356F -671F

Page 82: Classes of Polymeric Materials

82

Physical Properties of Polyester PET PBT LCP Polyester

Optical Transparent toOpaque

Opaque Opaque

Tmelt 245C -265 C 220C – 267C 400 C - 421 C

Tg 73C - 80C

H20Absorption

0.1 - 0.2% (24h) 0.085% (24h)0.45% (Max)

<0.1% (24h)<0.1% (Max)

OxidationResistance

good good good

UV Resistance Poor Poor none

SolventResistance

Attacked byhalogen

hydrocarbons

good good

AlkalineResistance

Poor Poor Poor

AcidResistance

Poor Poor fair

Cost $/lb $0.53 $1.48 $7.00 - $10.00

Page 83: Classes of Polymeric Materials

83

Advantages and Disadvantages of Polyesters• Advantages

– Tough and rigid and PBT has low moisture absorption

– Processed by thermoplastic operations

– Recycled into useful products as basis for resins in such applications as sailboats, shower units, and floor tiles

– PET flakes from PET bottles are in great demand for fiberfill for pillows and sleeping bags, carpet fiber, geo-textiles, and regrind for injection and sheet molding

• Disadvantages– Subject to attack by acids and bases

– Low thermal resistance

– Poor solvent resistance

– Must be adequately dried in dehumidifier prior to processing to prevent hydrolytic degradation.

Page 84: Classes of Polymeric Materials

84

Thermoplastic Copolyesters• Copolyester is applied to those polyesters whose synthesis uses

more than one glycol and/or more than one dibasic acid.• Copolyester chain is less regular than monopolyester chain and as

a result has less crystallinity• PCTA copolyester (Poly cyclo-hexane-dimethanol-terephthalate

acid) [amorphous]– Reaction includes cyclohexanedimethanol and terephthalic acid with

another acid substituted for a portion of the terephthalic acid– Extruded as transparent film or sheets that are suitable for packaging

applications (frozen meats shrink bags, blister packages, etc..)

• Glycol-modified PET (PETG) [amorphous]– Blow-molded containers, thermoformed blister packages.

Page 85: Classes of Polymeric Materials

85

ABS, PC Background • ABS was invented during WWII as a replacement for rubber

– ABS is a terpolymer: acrylonitrile (chemical resistance), butadiene (impact resistance), and styrene (rigidity and processing ease)

– Graft polymerization techniques are used to produce ABS– Family of materials that vary from high gloss to low matte finish, and

from low to high impact resistance.– Additives enable ABS grades that are flame retardant, transparent, high

heat-resistance, foamable, or UV-stabilized.

• PC was invented in 1898 by F. Bayer in Germany– Commercial production began in the US in 1959.– Amorphous, engineering thermoplastic that is known for toughness,

clarity, and high-heat deflection temperatures.– Polycarbonates are linear, amorphous polyesters because they contain

esters of carbonic acid and an aromatic bisphenol.

Page 86: Classes of Polymeric Materials

86

Polyamide History • PA is considered the first engineering thermoplastic• PA is one of many heterochain thermoplastics, which has atoms other

than C in the chain.• PA invented in 1928 by Wallace Carothers, DuPont, in search of a

“super polyester” fiber with molecular weights greater than 10,000. First commercial nylon in 1938.

• PA was created when a condensation reaction occurred between amino acids, dibasic acids, and diamines.

• Nylons are described by a numbering system which indicates the number of carbon atoms in the monomer chains– Amino acid polymers are designated by a single number, as nylon 6

– Diamines and dibasic acids are designated with 2 numbers, the first representing the diamine and the second indicating the adipic acid, as in nylon 6,6 or nylon 6,10 with sebacic acid.

Page 87: Classes of Polymeric Materials

87

Chemistry & Chemical Structurelinear polyamides• Thermoplastic nylons have amide (CONH) repeating link

• Nylon 6,6 - poly-hexamethylene-diamine (linear)NH2(CH2)6NH2 + COOH(CH2)4COOH

hexamethylene diamine + Adipic Acid

n[NH2(CH2)6NH . CO (CH2)4COOH ] + (heat)

nylon salt

[NH2(CH2)6NH . CO (CH2)4CO ]n + nH2O

Nylon 6,6 polymer chain

• Nylon 6 - polycaprolactam (linear)[NH(CH2)5CO ]n

Page 88: Classes of Polymeric Materials

88

Chemistry & Chemical Structurelinear polyamides

• Nylon 6, 10 - polyhexamethylenesebacamide (linear)

[NH2(CH2)6NH . CO (CH2)8CO]n

• Nylon 11 - Poly(11-amino-undecanoic-amide (linear)[NH(CH2)10CO ]n

• Nylon 12 - Poly(11-amino-undecanoic-amide (linear) [NH(CH2)11CO ]n

• Other Nylons– Nylon 8, 9, 46, and copolymers from other diamines and acids

Page 89: Classes of Polymeric Materials

89

Chemistry & Chemical StructureAromatic polyamides (aramids)

• PMPI - poly m-phenylene isophthalamide (LCP fiber)

[ -NHCO - NHCO ]n

• PPPT - poly p-phenylene terephthalamide (LCP fiber)

[ -NHCO - NHCO ]n

• Nomax PMPI - first commercial aramid fiber for electrical insulation. LCP fibers feature straight chain crystals

• Kevlar 29 PPPT- textile fiber for tire cord, ropes, cables etc.• Kevlar 49 PPPT - reinforcing fiber for thermosetting resins

Page 90: Classes of Polymeric Materials

90

Chemistry & Chemical StructureTransparent polyamides

• PA- (6,3,T)

[CH2C3H6C2H4-NHCO - NHCO ]n

• PA - (6,T)

[(CH2) 6NHCO - NHCO ]n

• Transparent polyamides are commercially available • Reduced crystallization due to introduction of side groups

Page 91: Classes of Polymeric Materials

91

Applications for Polyamides

• Fiber applications– 50% into tire cords (nylon 6 and nylon 6,6)

– rope, thread, cord,belts, and filter cloths.

– Monofilaments- brushes, sports equipment, and bristles (nylon 6,10)

• Plastics applications– bearings, gears, cams

– rollers, slides, door latches, thread guides

– clothing, light tents, shower curtains, umbrellas

– electrical wire jackets (nylon 11)

• Adhesive applications– hot melt or solution type

– thermoset reacting with epoxy or phenolic resins

– flexible adhesives for bread wrappers, dried soup packets, bookbindings

Page 92: Classes of Polymeric Materials

92

Mechanical Properties of Polyamides Mechanical Properties of Nylon

Nylon 6 Nylon 6,6 Nylon 6,10 Nylon 6,12Density, g/cc 1.13-1.15 1.13-1.15 1.09 1.06-1.10

Crystallinity 30-% - 50% 30-% - 50% 30-% - 50% 30-% - 50%

Molecular Weight 10,000–30,000 10,000–30,000 10,000–30,000 10,000–30,000

Tensile Strength,psi

6,000 – 24,000 14,000 8,500 – 8,600 6,500 – 8,800

Tensile Modulus,psi

300K 230K – 550K 250 K 220 - 290 K

TensileElongation, %

30% - 100% 15%-80% 70% 150%

Impact Strengthft-lb/in

0.6 – 2.2 0.55 – 1.0 1.2 1.0 –1.9

Hardness R80 - 102 R120 R111 M78

Page 93: Classes of Polymeric Materials

93

Physical Properties of Polyamide Nylon 6 Nylon 6,6 Nylon 6,10 Nylon 6,12

Optical Translucent toopaque

Translucent toopaque

Translucent to opaque Translucent to opaque

Tmelt 210C -220 C 255C – 265C 220 C 195 -219 C

Tg

H20Absorption

1.3-1.9% (24h)8.5-10 (Max)

1.0-2.8% (24h)8.5% (Max)

1.4% (24h)3.3% (Max)

0.4 – 1.0% (24h)2.5 –3 % (Max)

OxidationResistance

good good good good

UV Resistance Poor Poor Poor Poor

SolventResistance

Dissolved byphenol &

formic acid

Dissolved byphenol & formic

acid

Dissolved by phenol &formic acid

Dissolved by phenol &formic acid

AlkalineResistance

Resistant Resistant Resistant Resistant

AcidResistance

Poor Poor Poor Poor

Cost $/lb $1.30 $1.30 $3.00 $3.10

Page 94: Classes of Polymeric Materials

94

Advantages Disadvantages of Polyamide

• Advantages– Tough, strong, impact resistant– Low coefficient of friction– Abrasion resistance– High temperature resistance– Processable by thermopalstic methods– Good solvent resistance– Resistant to bases

• Disadvantages– High moisture absorption with dimensional instability

• loss of up to 30 % of tensile strength and 50% of tensile modulus– Subject to attack by strong acids and oxidizing agents– Requires UV stabilization– High shrinkage in molded sections– Electrical and mechanical properties influenced by moisture content– Dissolved by phenols

Page 95: Classes of Polymeric Materials

95

Additives and Reinforcements to PA• Additives- antioxidants, UV stabilizers, colorants, lubricants• Fillers

– Talc– Calcium carbonate

• Reinforcements– Glass fiber- short fiber (1/8” or long fiber 1/4”)– Mineral fiber (wolastonite)– carbon fibers– graphite fibers– metallic flakes– steel fibers

Page 96: Classes of Polymeric Materials

96

Properties of Reinforced Nylon

Nylon 6,6 Nylon 6,6 with30% short glass

Nylon 6,6 with30% long glass

Nylon 6,6 with30% carbon fiber

Density, g/cc 1.13-1.15 1.4 1.4 1.06-1.10

Crystallinity 30-% - 50% 30-% - 50% 30-% - 50% 30-% - 50%

Molecular Weight 10,000–30,000 30,000 10,000–30,000 10,000–30,000

Tensile Strength,psi

14,000 28,000 28,000 32,000

Tensile Modulus,psi

230K – 550K 1,300K 1,400 K 3,300 K

TensileElongation, %

15%-80% 3% 3% 4%

Impact Strengthft-lb/in

0.55 – 1.0 1.6-4.5 4.0 1.5

Hardness R120 R120 E60 R120

Moisture % 1.0-2.8% (24h)8.5% (Max)

0.7-1.1 (24h)5.5-6.5 (Max)

0.9 (24h)5.5-6.5 (Max)

0.7 (24h)5 (Max)

Cost $/lb $1.40 $1.70 $2.00 $2.70

Page 97: Classes of Polymeric Materials

97

Other Heterochain Polymers

• Polyimide– Developed by Du Pont in 1962

– Obtained from a condensation polymerization of aromatic diamine and an aromatic dianhydride

– Characterized as Linear thermoplastics that are difficult to process

– Many polyimides do not melt but are fabricated by machining

– Molding can occur if enough time for flow is allowed for T>Tg

• Advantages– High temperature service (up to 700C)

– Excellent barrier, electrical properties, solvent and wear resistance

– Good adhesion and ezpecially suited for composite fabrication

ONCO

NCO

CO CO

Page 98: Classes of Polymeric Materials

98

Other Heterochain Polymers• Polyimide Disadvantages

– Difficulty to fabricate and requires venting of volatiles– Hydroscopic– Subject to attacks by alkalines– Comparatively high cost

• Applications– Aerospace, electronics, and nuclear uses (competes with flurocarbons)– Office and industrial equipment; Laminates, dielectrics, and coatings– Valve seats, gaskets, piston rings, thrust washers, and bushings

• Polyamide-imide– Amorphous member of imide family, marketed in 1972 (Torlon), and used in

aerospace applications such as jet engine components– Contains aromatic rings and nitrogen linkage– Advantages include: High temperature properties (500F), low

coefficient of friction, and dimensional stability.

Page 99: Classes of Polymeric Materials

99

Other Heterochain Polymers• Polyacetal or Polyoxymethylene (POM)

– Polymerized from formaldehyde gas– First commercialized in 1960 by Du Pont– Similar in properties to Nylon and used for plumbing fixtures, pump impellers, conveyor

belts, aerosol stem valves, VCR tape housings

• Advantages– Easy to fabricate, has glossy molded surfaces, provide superior fatigue endurance, creep

resistance, stiffness, and water resistance.– Among the strongest and stiffest thermoplastics.– Resistant to most chemicals, stains, and organic solvents

• Disadvantages– Poor resistance to acids and bases and difficult to bond– Subject to UV degradation and is flammable– Toxic fumes released upon degredation

H-O-(CH2-O-CH2-O)NH:R

Page 100: Classes of Polymeric Materials

100

Mechanical Properties Nylon 6 Acetal Polyimid Polyamide-imide

Density, g/cc 1.13-1.15 1.42 1.43 1.41

Crystallinity 30-% - 50%

Molecular Weight 10,000–30,000

Tensile Strength,psi

6,000 – 24,000 10,000 10,000 26,830

Tensile Modulus,psi

300K 520K

TensileElongation, %

30% - 100% 40% - 75%

Impact Strengthft-lb/in

0.6 – 2.2 0.07 0.9 2.5

Hardness R80 - 102 R120 E50 E78

Tmelt 210 - 220 C 175-181 C Tg=275CMoisture24 hrmax

1.3 - 1.9%8.5 - 10%

0.25 to 0.40%1.41%

0.32% .28%

Optical Translucent toopaque

Translucent toopaque

opaque Transparent toopaque

Page 101: Classes of Polymeric Materials

101

Polyester History • 1929 W. H. Carothers suggested classification of polymers into two

groups, condensation and addition polymers.

• Carothers was not successful in developing polyester fibers from linear aliphatic polyesters due to low melting point and high solubility. No commercial polymer is based on these.

• p-phenylene group is added for stiffening and leads to polymers with high melting points and good fiber-forming properties, e.g., PET.

• Polymers used for films and for fibers

• Polyesters is one of many heterochain thermoplastics, which has atoms other than C in the chain.

• Polyesters includes unsaturated (thermosets), saturated and aromatic thermoplastic polyesters.

Page 102: Classes of Polymeric Materials

102

Chemistry & Chemical Structurelinear polyesters (versus branched)

• Thermoplastic polyesters have ester(-C-O) repeating link• Polyester (linear) PET and PBT

C6H4(COOH)2 + (CH2)2(OH)2 -[(CH2)2 -O- C - C-O]-

terephthalic acid + ethylene glycol Polyethylene terephthalate (PET)

C6H4(COOH)2 + (CH2)4(OH)2 -[(CH2)4 -O- C - C-O]-

terephthalic acid + butylene glycol Polybutylene terephthalate (PBT)

O

O O

O O

Page 103: Classes of Polymeric Materials

103

Chemistry & Chemical Structurelinear polyesters (versus branched)

• Wholly aromatic copolyesters (LCP)– High melting sintered: Oxybenzoyl (does not melt below its decomposition temperature. Must be compression molded)– Injection moldable grades: Xydar and Vectra

– Xydar (Amoco Performance Products)• terephthalic acid, p,p’- dihydroxybiphenyl, and p-hydroxybenzoic acid

– Grade 1: HDT of 610F– Grade 2: HDT of 480 F

– Vectra (Hoechst Celanese Corp.)• para-hydroxybenzoic acid and hydroxynaphtholic acid

– Contains rigid chains of long, flat monomer units which are thought to undergo parallel ordering in the melt and form tightly packed fibrous chains in molded parts.

Page 104: Classes of Polymeric Materials

104

PET Chemical Structure and Applications• The flexible, but short, (CH2)2 groups tend to leave the chains

relatively stiff and PET is notes for its very slow crystallization. If cooled rapidly from the melt to a Temp below Tg, PET solidifies in amorphous form.

• If PET is reheated above Tg, crystallizaiton takes place to up to 30%.• In many applications PET is first pre-shaped in amorphous state and

then given a uniaxial (fibers or tapes) or biaxial (film or containers) crystalline orientation.

• During Injection Molding PET can yield amorphous transparent objects (Cold mold) or crystalline opaques objects (hot mold)

Page 105: Classes of Polymeric Materials

105

PBT Chemical Structure and Applications

• The longer, more flexible (CH2)4 groups allow for more rapid crystallization than PET.

• PBT is not as conveniently oriented as PET and is normally injection molded.

• PBT has a sharp melting transition with a rather low melt viscosity.

• PBT has rapid crystallization and high degree of crystallization causing warpage concerns

Page 106: Classes of Polymeric Materials

106

Thermoplastic Aromatic Copolyesters• Polyarylesters

– Repeat units feature only aromatic-type groups (phenyl or aryl groups) between ester linkages.

– Called wholly aromatic polyesters– Based on a combination of suitable chemicals

• p-hydroxybenzoic acid• terephthalic acid• isophthalic acid,• bisphenol-A

– Properties correspond to a very stiff and regular chain with high crystallinity and high temperature stability

– Applications include bearings, high temperature sensors, aerospace applications– Processed in injection molding and compression molding– Most thermoplastic LCP appear to be aromatic copolyesters

Page 107: Classes of Polymeric Materials

107

Applications for Polyesters (PET)• Blow molded bottles

– 100% of 2-liter beverage containers and liquid products

• Fiber applications – 25% of market in tire cords, rope, thread, cord, belts, and filter cloths.

– Monofilaments- brushes, sports equipment, clothing, carpet, bristles

– Tape form- uniaxially oriented tape form for strapping

• Film and sheets– photographic and x-ray films; biaxial sheet for food packages

• Molded applications- Reinforced PET [Rynite, Valox, Impet]

– luggage racks, grille-opening panels, functional housings such as windshield wiper motors, blade supports, and end bells

– sensors, lamp sockets, relays, switches, ballasts, terminal blocks

• Appliances and furniture– oven and appliance handles, coil forms for microwaves, and panels

-- pedestal bases, seat pans, chair arms, and casters

Page 108: Classes of Polymeric Materials

108

Applications for Polyesters (PBT and LCP)

• PBT - 30 M lbs in 1988• Molded applications (PBT) [Valox, Xenoy, Vandar, Pocan]

– distributers, door panels, fenders, bumper fascias– automotive cables, connectors, terminal blocks, fuse holders and motor

parts, distributor caps, door and window hardware

• Extruded applications– extrusion-coat wire– extruded forms and sheet produced with some difficulty

• Electronic Devices (LCP) [26 M lbs] [Terylene, Dacron, Kodel]

– fuses, oxygen and transmission sensors– chemical process equipment and sensors– coil

Page 109: Classes of Polymeric Materials

109

Mechanical Properties of Polyesters

Mechanical Properties of polyesterPET PBT LCP Polyester

Density, g/cc 1.29-1.40 1.30 - 1.38 1.35 - 1.40

Crystallinity 10% - 30% 60% >80%

Molecular Weight

Tensile Strength,psi

7,000 – 10,500 8,200 16,000 – 27,000

Tensile Modulus,psi

400K - 600K 280K – 435K 1,400K - 2,800K

TensileElongation, %

30% - 300% 50%-300% 1.3%-4.5%

Impact Strengthft-lb/in

0.25 - 0.70 0.7 - 1.0 2.4 - 10

CLTE10-6 in/in/C

65 60-95 25-30

HDT 264 psi 70F -100F 122F - 185F 356F -671F

Page 110: Classes of Polymeric Materials

110

Physical Properties of Polyester PET PBT LCP Polyester

Optical Transparent toOpaque

Opaque Opaque

Tmelt 245C -265 C 220C – 267C 400 C - 421 C

Tg 73C - 80C

H20Absorption

0.1 - 0.2% (24h) 0.085% (24h)0.45% (Max)

<0.1% (24h)<0.1% (Max)

OxidationResistance

good good good

UV Resistance Poor Poor none

SolventResistance

Attacked byhalogen

hydrocarbons

good good

AlkalineResistance

Poor Poor Poor

AcidResistance

Poor Poor fair

Cost $/lb $0.53 $1.48 $7.00 - $10.00

Page 111: Classes of Polymeric Materials

111

Advantages/Disadvantages of Polyesters• Advantages

– Tough and rigid

– Processed by thermoplastic operations

– Recycled into useful products as basis for resins in such applications as sailboats, shower units, and floor tiles

– PET flakes from PET bottles are in great demand for fiberfill for pillows and sleeping bags, carpet fiber, geo-textiles, and regrind for injection and sheet molding

– PBT has low moisture absorption

• Disadvantages– Subject to attack by acids and bases

– Low thermal resistance

– Poor solvent resistance

– Must be adequately dried in dehumidifier prior to processing to prevent hydrolytic degradation.

Page 112: Classes of Polymeric Materials

112

Thermoplastic Copolyesters• Copolyester is applied to those polyesters whose synthesis uses

more than one glycol and/or more than one dibasic acid.

• Copolyester chain is less regular than monopolyester chain and as a result has less crystallinity

• PCTA copolyester (Poly cyclo-hexane-dimethanol-terephthalate acid) [amorphous]– Reaction includes cyclohexanedimethanol and terephthalic acid with

another acid substituted for a portion of the terephthalic acid– Extruded as transparent film or sheets that are suitable for packaging

applications (frozen meats shrink bags, blister packages, etc..)

• Glycol-modified PET (PETG) [amorphous]– Blow-molded containers, thermoformed blister packages.

Page 113: Classes of Polymeric Materials

113

ABS Background • ABS was invented during WWII as a replacement for

rubber– ABS is a terpolymer: acrylonitrile (chemical resistance), butadiene

(impact resistance), and styrene (rigidity and processing ease)

– Graft polymerization techniques are used to produce ABS

– Family of materials that vary from high gloss to low matte finish, and from low to high impact resistance.

– Additives enable ABS grades that are flame retardant, transparent, high heat-resistance, foamable, or UV-stabilized.

Page 114: Classes of Polymeric Materials

114

PEEK History • Polyether-ether-ketone (PEEK) and Polyether ketone (PEK)

– PEEK invented by ICI in 1982. PEK introduced in 1987

• PEEK and PEK are aromatic polyketones– Volume for polyketones is 500,000 lbs per year in 1990. Estimated

to reach 3 to 4 million by 2000.

– Cost is $30 per pound (as of October 1998)

• Product Names– ICI: Vivtrex

– BASF: Ultrapak

– Hoechst Celanese: Hostatec

– DuPont: PEKK

– Amoco: Kadel

Page 115: Classes of Polymeric Materials

115

Chemistry & Chemical Structure• PEEK- Poly-ether-ether-ketone

O O C

• PEK- Poly-ether-ketone

O C

O

n

O

n

Page 116: Classes of Polymeric Materials

116

Chemical Synthesis• Synthesis of polyketones

– PEK: Formation of the carbonyl link by polyaroylation from low cost starting materials. Requires solvents such as liquid HF. Excessive solvents and catalyst cause the high material cost.

– PEEK: Formation of ether link using phenoxide anions to displace activated halogen.O

C ClOHF, catalyst

O

nO C + HCl + CO2 +H20

PEK

K2CO3, DPS

O

C FF OHOH+ PEEK + CO2 +H20 +KF

Page 117: Classes of Polymeric Materials

117

PEEK and PEK Applications• Aerospace: replacement of Al

– Fuel line brakes to replacement of primary structure

• Electrical– wire coating for nuclear applications, oil wells, flammability-critical mass

transit.

– Semi-conductor wafer carriers which can show better rigidity, minimum weight, and chemical resistance to fluoropolymers.

• Other applications– Chemical and hydrolysis resistant valves (replaced glass)

– Internal combustion engines (replaced thermosets)

– Cooker components (replaced enamel)

– Automotive components (replaced metal)

– High temperature and chemical resistant filters from fiber

– Low friction bearings

Page 118: Classes of Polymeric Materials

118

Mechanical Properties of PEEK Mechanical Properties

PEEK LCP Polyester Nylon 6,6Density, g/cc 1.30-1.32 1.35 - 1.40 1.13-1.15

Tensile Strength,psi

10,000 – 15,000 16,000 – 27,000 14,000

Tensile Modulus,psi

500K 1,400K - 2,800K 230K – 550K

TensileElongation, %

30% - 150% 1.3%-4.5% 15%-80%

Impact Strengthft-lb/in

0.6 – 2.2 2.4 - 10 0.55 – 1.0

Hardness R120 R124 R120

CLTE10-6 mm/mm/C

40 - 47 25-30 80

HDT 264 psi 320 F 356F -671F 180F

Page 119: Classes of Polymeric Materials

119

Physical Properties of PEEK Physical Properties

PEEK LCP Polyester Nylon 6,6Optical Opaque Opaque Translucent to opaque

Tmelt 334 C 400 C 255C – 265C

Tg 177 C

H20Absorption

0.1-0.14% (24h)0.5% (Max)

0.1% (24h)0.1% (Max)

1.0-2.8% (24h)8.5% (Max)

OxidationResistance

good Good good

UV Resistance Poor good Poor

SolventResistance

good good Dissolved by phenol &formic acid

AlkalineResistance

good Poor Resistant

AcidResistance

good fair Poor

Cost $/lb $30 $7 - $10 $1.30

Page 120: Classes of Polymeric Materials

120

Properties of Reinforced PEEK Mechanical Properties Reinforced

PEEK PEEK 30%glass fibers

PEEK with 30%carbon fibers

Density, g/cc 1.30-1.32 1.52 1.43

Tensile Strength,psi

10,000 – 15,000 23,000 – 29,000 31,000

Tensile Modulus,psi

500K 1,300K – 1,600K 1,900K – 3,500K

TensileElongation, %

30% - 150% 2%-3% 1% - 4%

Impact Strengthft-lb/in

1.6 2.1 – 2.7 1.5 – 2.1

Hardness R120 R120

CLTE10-6 mm/mm/C

40 - 47 12-22 15-22

HDT 264 psi 320 F 550F -600F 550F -610F

Page 121: Classes of Polymeric Materials

121

Processing Properties of PEEK

Processing PropertiesPEEK LCP Polyester Nylon 6,6

Tmelt 334 C 400 C - 420 C 255C – 265C

Recommended TempRange (I:Injection, E:Extrusion)

I: 660F – 750FE: 660F – 725F

I: 540F – 770F I: 500F – 620F

Molding Pressure 10 -20 kpsi 5 - 16 kpsi 1 -20 kpsi

Mold (linear) shrinkage(in/in)

0.011 0.001 – 0.008 0.007 – 0.018

Page 122: Classes of Polymeric Materials

122

Advantages and Disadvantages of Polyketones

• Advantages– Very high continuous use temperature (480F)– Outstanding chemical resistance– Outstanding wear resistance– Excellent hydrolysis resistance– Excellent mechanical properties– Very low flammability and smoke generation– Resistant to high levels of gamma radiation

• Disadvantages– High material cost– High processing temperatures

Page 123: Classes of Polymeric Materials

123

Polyphenylene Materials •Several plastics have been developed with the benzene ring in the backbone

»Polyphenylene

»Polyphenylene oxide (amorphous)

»Poly(phenylene sulfide) (crystalline)

»Polymonochloroparaxylene

O OO

S S S

CH2 CH2

Cl Cl

Page 124: Classes of Polymeric Materials

124

PPO and PPS Materials*Advantages of PPS *Advantages of PPO

- Usage Temp at 450F - Good fatigue and impact strength

- Good radiation resistance - Good radiation resistance

- Excellent dimensional stability - Excellent dimensional stability

- Low moisture absorption - Low oxidation

- Good solvent and chemical resistance

- Excellent abrasion resistance

*Disadvantages of PPS *Disadvantages of PPO- High Cost - High cost

- High process temperatures -Poor resistance to certain chemicals

- Poor resistance to chlorinated hydrocarbons

Page 125: Classes of Polymeric Materials

125

PPO and PPS Applications*PPS Applications *PPO Applications

- Computer components - Video display terminals

- Range components - Pump impellers

- Hair dryers - Small appliance housings

- Submersible pump enclosures - Instrument panels

- Small appliance housings - Automotive parts

Page 126: Classes of Polymeric Materials

126

PPS and PPO Mechanical Properties Mechanical Properties

PPS PPO Nylon 6,6Density, g/cc 1.30 1.04 – 1.10 1.13-1.15

Tensile Strength,psi

9,500 7,800 14,000

Tensile Modulus,psi

480K 360K 230K – 550K

TensileElongation, %

1% - 2% 60% - 400% 15%-80%

Impact Strengthft-lb/in

< 0.5 4 - 6 0.55 – 1.0

Hardness R123 R115 R120

CLTE10-6 mm/mm/C

49 60 80

HDT 264 psi 275 F 118F -210F 180 F

Page 127: Classes of Polymeric Materials

127

PPS and PPO Physical Properties Physical Properties

PPS PPO Nylon 6,6Optical Opaque Opaque Translucent to opaque

Tmelt 290 C 250 C 255 C – 265 C

Tg 88 C 110 – 140 C

H20Absorption

> 0.02% (24h) 0.01% (24h) 1.0-2.8% (24h)8.5% (Max)

OxidationResistance

good good good

UV Resistance fair fair Poor

SolventResistance

Poor inaromatics

Poor inaromatics

Dissolved by phenol &formic acid

AlkalineResistance

good good Resistant

AcidResistance

poor good Poor

Cost $/lb $2 $1.80 $1.30

Page 128: Classes of Polymeric Materials

128

PPS and PPO Processing Properties

Processing Properties

PPS PPO Nylon 6,6

Tmelt 290 C 250 C 255C – 265C

Recommended Temp Range (I:Injection, E:Extrusion)

I: 600F – 625F I: 400F – 600FE: 420F – 500F

I: 500F – 620F

Molding Pressure 5 – 15 kpsi 12 - 20 kpsi 1 -20 kpsi

Mold (linear) shrinkage (in/in) 0.007 0.012 – 0.030 0.007 – 0.018

• PPS frequently has glass fibers loaded up to 40% by weight»Tensile strength = 28 kpsi, tensile modulus = 2 Mpsi, HDT = 500F

•PPO is frequently blended with PS over a wide range of percentages. (Noryl from G.E.)

Page 129: Classes of Polymeric Materials

129

Section Review – Polyesters is one of many heterochain thermoplastics, which has atoms

other than C in the chain.

– Polyesters includes unsaturated (thermosets), saturated and aromatic thermoplastic polyesters.

– Condensation polymerization for Polyester

– Thermoplastic polyesters have ester(-C-O) repeating link

– Linear and aromatic polyesters

– Most thermoplastic LCP appear to be aromatic copolyesters

– Effects of reinforcements on polyester

– Effects of moisture environment on nylon

– If cooled rapidly from the melt to a Temp below Tg, PET solidifies in amorphous form. If reheated PET acquires 30% crystallinity

– PET has rigid group of (CH2)2 ; PBT has more flexible (CH2)4

– Copolyester chain is less regular than monopolyester chain and as a result has less crystallinity

O

Page 130: Classes of Polymeric Materials

130

Section Review

– PEEK and PEK are aromatic polyketones. – Ketone groups have R - O - R functionality.– Chemical structure of PEEK and PEK depicts benzene - oxygen - benzene

in backbone.– PEEK and PEK are used primarily in applications requiring high

temperature use and chemical resistance.– AP2C is a special version of PEEK with 68% continuous carbon fiber.– Polyphenylene materials are plastics with the benzene ring in the

backbone.– PPO and PPS are characterized as heterochain thermoplastics, which has

atoms other than C in the chain.– PPO and PPS are made via Condensation Polymerization.– PPS frequently has glass fibers loaded up to 40% by weight.– PPO is frequently blended with PS over a wide range of percentages.

O

Page 131: Classes of Polymeric Materials

131

Section Review • Major Topics

– Vinyl is a varied group- PVC, PVAc, PVOH, PVDC, PVB.

– PVC is the leading plastic in Europe and second to PE in the US.

– PVC is produced by addition polymerization from the vinyl chloride monomer in a head-to-tail alignment.

– PVC is partially crystalline (syndiotactic) with structural irregularity increasing with the reaction temperature.

– PVC (rigid) decomposes at 212 F leading to dangerous HCl gas

X1

– Vinyls have (CH2CX2) repeating link

– PS is Amorphous and made from addition polymerization

– PC is amorphous and made from condensation polymerization

– Effects of reinforcements on PP and PS

Page 132: Classes of Polymeric Materials

132

Section Review • Major Topics

– Isotactic, atactic, sydiotactic polypropylene definitions

– Differences between PP and PE

– Molecular Weight definition and forms (Weight Average, Mw, and Number Average, MA )

– Polydispersity definition and meaning

– Relation between Molecular weight and Degree of Polymerization (DP)

– Mechanical, physical, and processing properties of PP, Polybutylene, and polymethylpentene

– PP is produced with linear chains

Page 133: Classes of Polymeric Materials

133

Section Review • Key Terms and Concepts

– Polyolefin

– Molecular weight

– Number average molecular weight, weight average MW

– Polydispersity

– Polymer shrinkage

– Polymer blends

– Tensile Modulus

– Izod Impact Strength

Page 134: Classes of Polymeric Materials

134

Homework Questions #21. Define Polyvinyls, PS, PP, HDPE, chemical structure.

2. Compare the density PVC, PVB, PS, and PVDC which is higher/lower than PP.

3. Compare the density of HDPE, LDPE, UHMWPE, LLDPE to PP?

4. What is the tensile strength of PP with 0%, 30% glass fibers? What is the tensile modulus?

5. Plot tensile strength and tensile modulus of PVC, PS, PP, LDPE and HPDE to look like:

Tensile Strength,Kpsi

Tensile Modulus, Kpsi200 500

10

50

xLDPE

xHDPE

Page 135: Classes of Polymeric Materials

135

Homework Questions #2

6. Four typical Physical Properties of PVC are Optical = _______, Resistance to moisture= ______ , UV resistance= _____, solvent resistance=_______

7. The Advantages of PP are ________, ________, _______, and __________.

8. The Disadvantages of PP are ________, ________, _______, and __________.

9. Glass fiber affects PP by (strength) ________, (modulus)________, (impact)_______, (density) __________, and (cost) ____________.

10. Two Blends PVC are ___________, and __________.

Page 136: Classes of Polymeric Materials

136

Homework Questions #2

11. Define Polypropylene chemical structure

12. Does commercial PP have Isotactic, atactic, sydiotactic form.

13. If MW of PP is 200,000, what is the approx. DP?

14. Polydispersity represents the distribution of _______and _____

15. Density of PP is _____ which is higher/lower than HDPE.

16. PP mechanical properties are higher/lower than LDPE and HDPE

17. Plot tensile strength and tensile modulus of PP, LDPE and HPDE to look like the following

Tensile Modulus,Kpsi

Tensile Strength, Kpsi2 5

10

50

xLDPE

xHDPE

Page 137: Classes of Polymeric Materials

137

Homework Questions #2

18. Four typical Physical Properties of PP are Optical = _______, Resistance to moisture= ______ , UV resisance= _____, solvent resistance=_______

19. The Advantages of PP are ________, ________, _______, and __________.20. The Disadvantages of PP are ________, ________, _______, and __________.21. Glass fiber affects PP by (strength) ________, (modulus)________,

(impact)_______, (density) __________, and (cost) ____________.22. Five polyolefins are ________, ________, _______, ______, and __________.

Page 138: Classes of Polymeric Materials

138

Homework Questions

1. Define PEEK, PPO and PPS chemical structures.

2. How are the properties of PEEK and PPS alike?

3. Density of PEEK is _____, PPS is _____ , and PPO is _____ , which is higher/lower than PBT and nylon?

4. What is the tensile strength of PEEK with 0%, 30% glass fibers? What is the tensile modulus?

5. Plot tensile strength and tensile modulus of PEEK, PPO, PPS, PET, PBT, Nylon 6, PP, LDPE and HPDE to look like the following

Tensile Modulus,Kpsi

Tensile Strength, Kpsi2 5

10

50

xLDPE

xHDPE

Page 139: Classes of Polymeric Materials

139

Homework Questions

6. Four typical Physical Properties of PEEK are Optical = _______, Resistance to moisture= ______ , UV resistance= _____, acid resistance=_______

7. The Advantages of PEEK are ________, ________, _______, and __________.

8. The Disadvantages of PEEK are ________, ________, _______, and __________.

9. How are the properties of PPO and PPS alike? How are they different?

10. What are 3 advantages that Nylon has over PPO and PPS?_________________________________ _________________________________________________.

Page 140: Classes of Polymeric Materials

140

Homework Questions

1. Define PBT and PET chemical structure.

2. Why was Carothers not successful in developing polyesters?

3. Density of PET is _____ which is higher/lower than PBT and nylon?.

4. What is the tensile strength of PET with 0%, 30% glass fibers? What is the tensile modulus?

5. Plot tensile strength and tensile modulus of PET, PBT, Nylon 6, PP, LDPE and HPDE to look like the following

Tensile Modulus,Kpsi

Tensile Strength, Kpsi2 5

10

50

xLDPE

xHDPE

Page 141: Classes of Polymeric Materials

141

Homework Questions

6. Four typical Physical Properties of Polyester are Optical = _______, Resistance to moisture= ______ , UV resistance= _____, acid resistance=_______

7. The Advantages of Polyester are ________, ________, _______, and __________.

8. The Disadvantages of Polyester are ________, ________, _______, and __________.

9. Glass fiber affects Polyester by (strength) ________, (modulus)________, (elongation)_______, (density) __________, and (cost) ____________.

10. What affect does the copolymer have on the crystallinity of polyesters and why?_________________________________ _________________________________________________.

Page 142: Classes of Polymeric Materials

142

Homework Questions

1. Define Nylon 6,6 and Nylon 6 and Nylon 6,12 chemical structure

2. If MW of PA is 50,000, what is the approx. DP?

3. Density of PA is _____ which is higher/lower than PP.

4. What is the tensile strength of nylon 6,6 with 0%, 30% glass fibers? What is the tensile modulus?

5. Plot tensile strength and tensile modulus of Nylon 6, PP, LDPE and HPDE to look like the following

Tensile Modulus,Kpsi

Tensile Strength, Kpsi2 5

10

50

xLDPE

xHDPE

Page 143: Classes of Polymeric Materials

143

Homework Questions

6. Four typical Physical Properties of PA are Optical = _______, Resistance to moisture= ______ , UV resisance= _____, solvent resistance=_______

7. The Advantages of PA are ________, ________, _______, and __________.

8. The Disadvantages of PP are ________, ________, _______, and __________.

9. Glass fiber affects PA by (strength) ________, (modulus)________, (impact)_______, (density) __________, and (cost) ____________.

10. Two Aromatic PA are ___________, and __________.


Recommended