Thermoplastic copolyester elastomers modified with salts of aliphatic polycarboxylic acid

Abstract

A thermoplastic copolyester elastomer composition comprising (A) a copolyester consisting essentially of a multiplicity of long-chain ester units and short-chain ester units joined through ester linkages, said long-chain ester units being represented by the formula ##STR1## and said short-chain ester units being represented by the formula ##STR2## where G is a divalent radical remaining after the removal of hydroxyl groups from at least one long-chain glycol having a melting point of less than about 55.degree. C. and a number average molecular weight of from about 400-4000, R is a divalent radical remaining after removal of carboxyl groups from at least one dicarboxylic acid having a molecular weight of less than about 300, and D is a divalent radical remaining after the removal of hydroxyl groups from at least one aliphatic diol having a molecular weight of less than about 250, with the proviso that at least about 70 mole percent of the short-chain ester units are either ethylene terephthalate units or 1,4-butylene terephthalate units, said short-chain ester units being present in an amount of 15-95% by weight of said copolyester; and (B) from about 0.1 to 10% by weight based on said copolyester of at least one alkali metal salt of an aliphatic polycarboxylic acid containing at least 20 carbon atoms and having a molecular weight of less than about 1500.

Dependencies are inferred from the claim text.