高分子量立构复合结晶的三枝化PPO-PDLA-PLLA嵌段共聚物  

Three-arm Stereocomplexed PPO-PDLA-PLLA Copolymer with High Molecular Weight

作　　者：李伟[1] 马艳[1] 李远翔[1] 范仲勇[1] 

机构地区：[1]复旦大学材料科学系,上海200433

出　　处：《高等学校化学学报》2014年第7期1553-1558,共6页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:51373041)资助~~

摘　　要：以三枝化低不饱和度聚环氧丙烷(PPO)引发D-丙交酯(D-LA)逐步开环聚合,合成了三枝化聚环氧丙烷-聚右旋乳酸(PPO-PDLA)共聚物.用辛酸亚锡Sn(Oct)2与PPO-PDLA端羟基反应进行Sn(Oct)封端,制备了三枝化PPO-PDLA-Sn(Oct)预聚物.再于130℃下,以其作为大分子引发剂与L-丙交酯(L-LA)开环聚合,合成了分子量>105的三枝化PPO-PDLA-PLLA嵌段共聚物.活性端基的引入,降低了聚合反应温度,从而降低了聚合中的酯交换或热降解反应发生的概率.实现了高分子量PPO-PDLA-PLLA嵌段共聚物的合成.结构测试结果表明,合成的嵌段共聚物具有分子结构易控及立构规整度高等特点.在结晶-熔融-再结晶重复热处理下,三枝化PPO-PDLA-PLLA嵌段共聚物仅发生立构复合聚乳酸结晶,且结晶能力稳定.Three-arm poly （propylene oxide） （PPO） was used as a macroinitiator for the ring-opening polymerization（ROP） of D-lactide to obtain three-arm poly （propylene oxide）-block-poly （D-lactic acid）（ PPO- PDLA）. PPO-PDLA eopolymer was then reacted with stannous octoate [Sn（Oct） 2 ] to obtain Sn（Oct） end- capped PPO-PDLA [ PPO-PDLA-Sn （Oct） ]. The PPO-PDLA-Sn （Oct） can be used as an efficient macroinitiator for the ROP of L-lactide to synthesize three-arm PPO-PDLA-PLLA at 130 ℃, which reduces the occurrence of hydrolysis and transesterification reaction. PPO-PDLA-PLLA copolymers with high molecular weight were synthesized by this novel and simple method. The results show that the composite of PPO-PDLA-PLLA can be easily tuned by controlling the feed ratio of L-lactide and D-lactide, and the stereoregularity of PPO-PDLA- PLLA is high. Moreover, the stereocomplexes of PPO-PDLA-PLLA can survive melting to reform the stereocomplex crystallites.

关 键 词：封端 开环聚合 立构嵌段聚乳酸 三枝化PPO—PDLA—PLLA嵌段共聚物 立构复合结晶 

分 类 号：O631[理学—高分子化学]