A copolyester includes repeating units derived from an aliphatic glycol, terephthalic acid, and the monomer of formula (I):
wherein n=2, 3 or 4; Z is C═O; comonomer (I) constitutes a proportion of the glycol fraction of the copolyester and is present in a range of from about 5 to about 15 mol % of the glycol fraction of the copolyester; wherein said copolyester is semi-crystalline. A process tor making the copolyester includes annealing a copolyester of formula (I) at 20-80° C. below the crystalline melting point (Tm) and above the glass transition temperature (Tg).
共聚聚酯包括由脂肪族
乙二醇、
对苯二甲酸和式 (I) 单体衍生的重复单元:
其中 n=2、3 或 4;Z 为 C═O;共聚单体 (I) 占共聚聚酯
乙二醇部分的比例,其含量为共聚聚酯
乙二醇部分的约 5 至约 15 摩尔%;所述共聚聚酯为半结晶。制造共聚聚酯的工艺包括在低于结晶熔点(Tm)和高于
玻璃化温度(Tg)的 20-80°C 下退火式(I)共聚聚酯。