摘要 |
<p>Fibre-forming polyesters are prepared by forming a polyester from a dicarboxylic acid and a glycol and reducing the concentration of the carboxyl end groups in the polyester by reaction with a glycidyl ether <FORM:1093840/C3/1> wherein R is an aliphatic, cycloaliphatic or aromatic group and R1 is H or an aliphatic, cycloaliphatic or aromatic group. In examples polyesters are prepared from dimethyl terephthalate and ethylene glycol i.p.o. Zn, Mn or Co acetate and Sb2O3 and optionally TiO2, and stabilized with triphenyl or tributyl phosphite; the properties with and without after-treatment are compared, the glycidyl compounds used being the phenyl, butyl, allyl, o-chlorophenyl and 2-chloroethyl glycidyl ethers. The intrinsic viscosities and softening points all lie in the ranges 0.63-0.985 and 254-262 DEG C. respectively; the ranges of carboxyl content are 31.5-53 equivalents/106 gm. and 6.0-28.7 equivalent/106 gm. without and with treatment, respectively.</p> |