Highly crystalline thermoplastic terephthalic acid copolymers - contain terephthalic acid gp, ethylene glycol gp and co-diol gps

摘要

Highly crystalline and rapidly crystallising thermoplastic terephthalic acid copolymers contg. >90 mole% terephthalic acid groups, based on the dicarboxylic acid component, 90-95 mole% ethylene glycol group, and 0.5-10 mole% Co-diol groups, based on the diol component, are characterised in that (a) the co-diols used have 2 primary OH groups, (b) these 2 OH groups are separated by 3-4C and (c) the co-diols are opt. substd. by 2 alkyl groups contg. 2-3C. The prods. crystallise much faster than pure polyethylene terephthalate and have very high m.pt., which are desirable features for moulding.