不同二元醇制备的4种脂肪/芳香共聚酯的性能研究

利用4种不同的脂肪族二元醇（乙二醇、1,3 丙二醇、1,4 丁二醇、1,6 己二醇）与己二酸和对苯二甲酸二甲酯制备出4种不同脂肪/芳香比的共聚酯：（对苯二甲酸乙二醇-co-己二酸乙二醇）共聚酯（PETA）、（对苯二甲酸丙二醇-co-己二酸丙二醇）共聚酯（PPTA）、（对苯二甲酸丁二醇-co-己二酸丁二醇）共聚酯（PBTA）和（对苯二甲酸己二醇-co-己二酸己二醇）共聚酯（PHTA），并比较了它们的热性能和生物降解性能。结果表明：相同二元醇、不同脂肪/芳香物质的量比的共聚酯，随脂肪族单体含量的增加，玻璃化转变温度（T_g）单调降低，熔点（T_m）降低，生物降解能力增加；相同脂肪/芳香物质的量的比、不同二元醇制备的共聚酯，T_g随二元醇碳原子的增加而单调下降，T_m变化顺序为：T_m（PPTA）＞T_m（PBTA）＞T_m（PHTA）＞T_m（PETA），1,3-丙二醇体系的共聚酯具有最佳的耐热性能；生物降解能力随二元醇单体碳原子数的增加而增加。

Properties of four aliphatic/aromatic copolyesters based on different diols

Linear aliphatic/aromatic copolyesters have been synthesized. using dimethyl terephthalate, adipic acid and four diols (ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,6-hexanediol) with different aliphatic/aromatic feed molar ratios. The thermal properties and biodegradabilities of poly(ethylene terephthalate-co-ethylene adipate) (PETA), poly(propylene terephthalate-co-propylene adipate) (PPTA), poly(butylene terephthalate-co-butylene adipate) (PBTA) and poly(hexylene terephthalate-co-hexylene adipate) (PHTA) were studied. For copolyesters prepared from the same diol but with different feed molar ratios, the glass transition temperature (T_g) decreased monotonically and both the melting temperature (T_m) and biodegradabilities increased with increasing content of aliphatic unit. As far as copolyesters with the same aliphatic/aromatic feed molar ratios but prepared from different diols are concerned, the biodegradabilities increased and T_g decreased with the increasing number of carbon atoms in the aliphatic diol. The value of T_m was found to decrease in the order T_m (PPTA)＞T_m(PBTA)＞T_m (PHTA)＞T_m(PETA), indicating that PPTA has the best thermal properties. 