| 摘要 |
1403324 Stabilized copolyesters E I DU PONT DE NEMOURS & CO 15 Feb 1973 [16 Feb 1972] 7532/73 Heading C3R A process for preparing a stabilized segmented thermoplastic copolyester comprises reacting a poly-(alkylene oxide) glycol of molecular weight 400-4000 and a carbon to oxygen ratio of 1À8:1 to 4À3 : 1, a diol of molecular weight less than 250 and a dicarboxylic acid of molecular weight less than 300, wherein at least the polycondensation is carried out in the presence of 4,4<SP>1</SP>-bis- (α,α-dimethylbenzyl) diphenylamine. The stabilizer is preferably present in an amount of 0À05 to 2À0% by weight, based on the copolyester. The examples describe preparing copolyesters from poly-(tetramethylene ether) glycol, 1,4- butanediol and dimethyl terephthalate in the presence of the above stabilizer. U.V. stabilizers and fillers, e.g. carbon black, silica gel, alumina, clay and chopped glass fibre, may be added to the copolyester. |
