文献类型：期刊文献

英文题名：Thermal and phase-separation behavior of injection-molded poly(L-lactic acid)/poly(D-lactic acid) blends with moderate optical purity

作者：Xu, Huijun[1];Tang, Songchao[1];Chen, Jianding[1];Yin, Peimin[2];Pu, Weiliang[2];Lu, Yuan[1]

机构：[1]E China Univ Sci & Technol, Shanghai Key Lab Adv Polymer Mat, Key Lab Ultrafine Mat, Minist Educ,Sch Mat Sci & Engn, Shanghai 200237, Peoples R China;[2]Shanghai Acad Biomat Corp Ltd, Shanghai 201512, Peoples R China

年份：2012

卷号：68

期号：4

起止页码：1135

外文期刊名：POLYMER BULLETIN

收录：;EI(收录号：20121614945917);WOS:【SCI-EXPANDED(收录号:WOS:000300329300019)】；

基金：This study is supported by the National Natural Science Foundation of China (No. 51173041), Shanghai Leading Academic Discipline Project (B502), and Shanghai Key Laboratory Project (08DZ2230500).

语种：英文

外文关键词：Polylactide; Stereocomplexes; Crystallization; Optical purity; Micro-phase separation

摘要：l-Lactide-rich poly(l-lactide) (LR-PLLA)/d-lactide-rich poly(d-lactide) (DR-PDLA) blends with moderate optical purity were prepared by conventional extrusion and followed by injection-molding process in this study. Thermal properties, crystalline structure, spherulite morphology, melt degradability, and thermal mechanical property were investigated by means of DSC, WAXD, POM, TG, and DMA. In comparison with LR-PLLA/DR-PDLA blends with higher optical purity, stereocomplex with less perfect structure was partially formed from the LR-PLLA/DR-PDLA blends with various compositions and showed lower melting temperature. Surprisingly, double melting peaks have appeared in blends with 40 or 50 wt% DR-PDLA. Annealing at higher temperature for blends with 50 wt% DR-PDLA resulted in three melting peaks. It is assumed that the optical purity would play a critical role, thus, producing limited amount of stereocomplex with less imperfect structure. Annealing would also induce the micro-phase separation behavior in LR-PLLA/DR-PDLA blends and significantly influence the thermal and degradable properties of blends.