Thermoplastic molding compositions

Claim 1

An improved molding composition, having improved mold releasability, said composition comprising: (a) a block copolymer derived from blocks of (i) a terminally reactive poly(1,4-butylene terephthalate) and (ii) a terminally reactive aromatic/aliphatic copolyester of a dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid, naphthalene dicarboxylic acids, phenyl indane dicarboxylic acid and compounds of the formula ##STR3## in which X may be alkylene or alkylidene of from 1 to 4 carbon atoms, carbonyl, sulfonyl, oxygen or a bond between the benzene rings, and an aliphatic dicarboxylic acid having from 6 to 12 carbon atoms in the chain and one or more straight or branched chain dihydric aliphatic glycols having from 4 to 10 carbon atoms in the chain, said copolyester having at least 10% of aliphatic units being derived from a dicarboxylic acid; or (iii) a terminally-reactive aliphatic polyester of a straight chain aliphatic dicarboxylic acid having from 4 to 12 carbon atoms in the chain and a straight or branched chain aliphatic glycol, said blocks being connected by interterminal linkages consisting essentially of ester linkages; (b) from about 0.25 to 4.5 percent by weight, based on the total composition, of a composition, of a polyolefin or olefin-based copolymer; and (c) from about 0.02 to about 0.5% by weight, based on the total composition, of talc.