PROCESS FOR PREPARING COPOLYESTERS AND PRODUCTS OBTAINED THEREBY

摘要

1402973 Preparing copolyesters EASTMAN KODAK CO 1 Feb 1973 [2 Feb 1972] 5117/73 Heading C3R [Also in Division G2] A process for preparing a second polyester from a first polyester comprises (a) mixing (i) a first polyester having the structure where R 1 is an aliphatic radical, an alicyclic radical or an aromatic radical, R 2 is an aliphatic radical or an alicyclic radical, x is 0 or 1 and n is a positive integer, (ii) a dicarboxylic acid HO 2 C-R 3 -CO 2 H where R 3 is an aliphatic radical, an alicyclic radical or an aromatic radical, and (iii) an aromatic diester R 4 O 2 CAr-CO 2 R 5 where R 4 and R 5 are alkyl radicals, cycloalkyl radicals or aryl radicals and Ar is an arylene radical; (b) heating the mixture to form a melt and (c) removing the non-polymeric byproducts of the reaction whereby the reaction equilibrium is driven in the direction of polymer formation and the second polyester is obtained. The reactants used in the examples are (i) as first polyester:- polyethylene terephthalate, polyethylene isophthalate, polyethylene sebacate, polyethylene adipate, polyethylene azelate, poly- 1,3-trimethylene terephthalate), poly-(1,6-hexamethylene terephthalate), poly- (ethylene-2,6-naphthalate), poly-(1,4-cyclohexylene dimethylene terephthalate), poly-(2,2- dimethyl-1,3-trimethylene terephthalate) and poly - (2,2,4,4 - tetramethyl - 1,3 - cyclobutylene terephthalate), (ii) as dicarboxylic acid:- terephthalic, isophthalic, sebacic, adipic and azeloic acids, and (iii) as aromatic diester:- bisphenol A diacetate, p-phenylene diacetate and m-phenylene diacetate.