环氧丙烷聚醚三元醇／聚乳酸嵌段共聚物的合成与性能  

Synthesis and Characterization of Poly(propylene oxide-lactide) Diblock Copolymer

作　　者：逯琪[1] 杨冬梅[1] 张宇婷[1] 于瀛[1] 李速明[1] 涂建军[2] 王巍[2] 范仲勇[1] 

机构地区：[1]复旦大学材料科学系,上海200433 [2]上海石油化工研究院,上海201208

出　　处：《化学学报》2009年第3期249-254,共6页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.20474013,20674013);上海市重点学科建设项目(No.B113)资助项目

摘　　要：以低不饱和度环氧丙烷聚醚三元醇与L型及DL型丙交酯为原料,合成了不同单体物质的量比的聚醚与聚乳酸嵌段共聚物.采用FTIR,1HNMR,GPC对共聚物的结构进行了表征;用DSC,DTA对共聚物的玻璃化转变温度、熔点及热分解温度进行了研究.结果表明,丙交酯在聚醚多元醇端羟基的引发下发生开环反应,得到聚环氧丙烷L型乳酸(POLLA)或聚环氧丙烷DL型乳酸(PODLA)二嵌段共聚物.POLLA二嵌段共聚物具有结晶能力,且随着L型聚乳酸链段的增长而增强.PODLA二嵌段共聚物为非晶态聚合物.两种共聚物的玻璃化转变温度与共聚物的组成有关,其值介于聚醚和聚乳酸玻璃化转变温度之间.与聚醚三元醇相比,二嵌段共聚物的耐热性得到提高,其热分解温度提高了30～60℃,约为235～262℃.共聚物的结构和组成对材料的热降解机制有很大影响.PODLA在高温区发生热氧化降解。Different molar ratios of poly（propylene oxide-lactide） diblock copolymers were synthesized from low unsaturated poly（propylene oxide） triols and L- or DL-lactide monomers. The structure of the copolymers was determined by means of FTIR, ^1H NMR and GPC, and the thermal behavior was characterized by DSC and TGA. The results turned out that poly（propylene oxide-L-lactide） （POLLA） or poly（propylene oxide-DL-lactide） （PODLA） diblock copolylmers were synthesized by ring-opening polymerization of lactide with poly（propylene oxide） triol. The POLLA diblock copolymers were semi-crystalline copolymers, and the crystallinity was increased with the increase of LLA segments. However, the PODLA diblock copolymers were amorphous ones. The glass transition temperature of the copolymers was influenced by the composition of the copolymers, and the tested Tg was between the values of the two homopolymers. Compared with poly（propylene oxide）, the thermal stability of the diblock copolymers was improved. The thermal decomposition temperature of the copolymers was between 235 and 262 ℃, which was 30-60 ℃ higher than that of poly（propylene oxide）. The results also showed that the chemical structures of various diblock copolymers had an effect on the thermal decomposition kinetic of samples. The mechanism of thermal oxidative decomposition of PODLA was observed in a high temperature region.

关 键 词：聚环氧丙烷 聚乳酸 嵌段共聚物 合成 性能 

分 类 号：O631.3[理学—高分子化学]