writer：Chengqian Pan, Jing Lu, Binshuang Wu, Linbo Wu*, Bo-Geng Li.
keywords：Biodegradable polymers, Flexible copolyesters, Aliphatic–aromatic copolyesters, Crystallization, Glass transition
source：期刊
specific source：J Polym Environ (2017) 25(4):1051–1061
Issue time：2017年

Amorphous flexible (co)polyesters with low glass transition temperature (Tg) are very desirable in impact modification of biodegradable brittle polymers and synthesis of biodegradable elastomers. However, most flexible polyesters and binary copolyesters made from linear diacid(s) and diol(s) are crystalline polymers. In order to investigate the effect of monomer structure on the crystallization and Tg of such copolyesters, novel ternary or multiple flexible copolyesters containing various structural units were designed and synthesized in this study, and characterized with 1HNMR, GPC, DSC, WAXD, TGA and tensile testing. Introducing aromatic diacid (especially asymmetric one) or short-chain branched

diol is favorable to depress copolyester crystallization, and leads to higher Tg at the same time. From easily crystallized to fully amorphous copolyesters with low Tg were successfully synthesized by adopting different combination of structural units. In addition, the existence of aromatic structural unit in copolyesters is helpful to improve their tensile properties.