【作者】 吴小蒙； 马艳； 李伟； 范仲勇；

【Author】 Xiaomeng Wu;Yan Ma;Wei Li;Zhongyong Fan;Department of Materials Science,Fudan University;

【机构】 复旦大学材料科学系；

【摘要】 以正辛醇(Oct.)和三枝化环氧丙烷三元醇(PPO)为起始剂,开环聚合D型丙交酯(DLA),分别合成线型和三枝化的右旋聚乳酸(Oct-PDLA、PPO-PDLA)预聚体。采用辛酸亚锡对预聚体进行封端处理,再与L型丙交酯(LLA)进行逐步开环聚合,合成了一系列分子量>2?105的线型辛醇-右旋聚乳酸-左旋聚乳酸(Oct-PDLA-PLLA)和三枝化环氧丙烷聚醚多元醇-右旋聚乳酸-左旋聚乳酸(PPO-PDLA-PLLA)嵌段共聚物新材料。通过差示扫描量热仪(DSC)和广角X射线衍射(WAXD)对材料进行表征。结果显示,线型Oct-PDLA-PLLA和三枝化PPO-PDLA-PLLA嵌段共聚物的异构体链段分子间生成立构复合晶体(sc-PLA),其结晶温度(90℃)比PLLA低15℃,熔点约为200℃比PLLA高出30℃左右。此外,在结晶-熔融-再结晶过程中,PDLA-PLLA嵌段共聚物都仅发生立构复合聚乳酸结晶,说明该类材料具有良好的热稳定性。更多还原

【Abstract】 Linear and triarm Oct-PDLA and PPO-PDLA block copolymers were synthesized by ring-opening polymerization of D-lactide(DLA) using octanol and low unsaturated poly(propylene oxide)(PPO) as the initiator. Then, the PDLA-PLLA block copolymers were successfully synthesized with various high molecular weight by ring-opening process of L-lactide(LLA) using functioned prepolymer as the macromolecular initiator. The results show that the crystallization temperature of block copolymers decreased 15oC and the melt temperatures increased 30oC compared with neat PLLA. Furthermore, the stereocomplexes of block copolymers were able to survive from melting to reform the stereocomplex crystallites.更多还原