Page 271 - Carrahers_Polymer_Chemistry,_Eighth_Edition

234 Carraher’s Polymer Chemistry

TABLE 7.3
Common Elastomers and Their Uses
Common Name (Chemical Composition) Abbreviation Uses and Properties
Acrylonitrile–butadiene–styrene (terpolymer) ABS Oil hoses, fuel tanks, gaskets, pipe and fi ttings,
appliance and automotive housings. Good resistance to
oils and gas
Butadiene rubber BR Tire tread, hose, belts. Very low hysteresis; high
rebound
Butyl rubber (from isobutene and 0.5%–3% IIR Innertubes, cable sheathing, tank liners, roofi ng, Seals,
isoprene) coated fabrics. Very low rebound; high hysteresis
Chloroprene rubber (polychloroprene) CR Wire and cable insulation, hose footwear, mechanical
automotive products. Good resistance to oil and fi re,
good weatherability
Epichlorohydrin (epoxy copolymers) Seals, gaskets, wire and cable insulation. Good
resistance to chemicals
Ethylene–propylene rubbers (random EP or EPM Cable insulation, window strips. Outstanding insulative
copolymers with 60%–80% ethylene) properties
Ethylene–propylene–diene (random EPDM Good resistance to weathering, resistant to ozone attack
terpolymers)
Fluoroelastomers (fl uorine-containing Wire and cable insulation, aerospace applications.
copolymers) Outstanding resistance to continuous exposure to high
temperatures, chemicals, and fl uids
Ionomers (largely copolymers of ethylene Golf ball covers, shoe soles, weather stripping

and acid-containing monomers with metal Tough, flame-resistant, good clarity, good electrical
ions) properties, abrasion-resistant
Natural rubber (polyisoprene) NR General-purpose tires, bushings, and couplings, seals,
footwear, belting. Good resilience
Nitrile rubber (random copolymer of NBR Seals, automotive parts that are in contact with oils and
butadiene and acrylonitrile) gas, footwear, hose Outstanding resistance to oils and
gas, little swelling in organic liquids

Polysulfide Adhesive, sealants, hose binders
Outstanding resistance to oil and organic solvents
Polyurethanes PU Sealing and joining, printing rollers, fi bers, industrial
tires, footwear, wire and cable coverings
Silicones (generally polydimethylsiloxane) Medical applications, flexible molds, gaskets, seals.

Extreme-use temperature range
Styrene–butadiene rubber (random SBR Tire tread, footwear, wire and cable covering, adhesives.
copolymer) High hysteresis

interlinked network. While there has been a lot of research done with such graft materials they have
not yet become very important commercially.

-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-
| | | (7.36)
(B) n (B) n (B) n

Thermoplastic elastomers can also be achieved through physical mixing of hard and soft seg-

ments (Table 7.6). These are fine dispersions of a hard thermoplastic polymer and an elastomer. The
two materials generally form interdispersed cocontinuous phases. Often the physical combining is
achieved through intense mechanical mixing but in some cases, such as with polyporpylene and

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