Process for the preparation of copolyesters based on 2,2,4,4-tetramethyl-1,3-cyclobutanediol and 1,4-cyclohexanedimethanol

摘要

Disclosed is a process for the preparation of high molecular weight, thermoplastic copolyesters by reacting a diester composition comprising a dialkyl ester of terephthalic acid with a diol composition comprising a first diol component comprising 2,2,4,4-tetramethyl-1,3-cyclobutanediol and a second diol component comprising 1,4-cyclohexanedimethanol. The diester composition can be reacted with the first diol component to produce a polyester oligomer that can be reacted further with the second diol component to produce a modified polyester oligomer. The modified polyester oligomer can then be heated to form a copolyester. The process reduces the precipitation of poly(1,4-cyclohexylene dimethylene) terephthalate in the reaction mixture.