Names | |
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IUPAC name
Poly(oxy-1,4-butanediyloxycarbonyl-1,4-phenylenecarbonyl)
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Identifiers | |
ChemSpider |
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Properties[1] | |
(C12H12O4)n | |
Melting point | 223 °C (433 °F; 496 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Polybutylene terephthalate (PBT) is a thermoplastic engineering polymer that is used as an insulator in the electrical and electronics industries.[2] It is a thermoplastic (semi-)crystalline polymer, and a type of polyester. PBT resists solvents, shrinks very little during forming, is mechanically strong, is heat-resistant up to 150 °C (or 200 °C with glass-fibre reinforcement), and can be treated with flame retardants to make it noncombustible. It was developed by Britain's Imperial Chemical Industries (ICI).[3]
PBT is closely related to other thermoplastic polyesters.[2] Compared to PET (polyethylene terephthalate), PBT has slightly lower strength and rigidity, slightly better impact resistance, and a slightly lower glass transition temperature. PBT and PET are sensitive to hot water above 60 °C (140 °F). PBT and PET need UV protection if used outdoors, and most grades of these polyesters are flammable, although additives can be used to improve both UV and flammability properties.
PBT is produced by the polymerization of 1,4-butanediol and terephthalic acid.[4][5]