中文摘要：

以辛酸亚锡为催化剂,通过开环聚合法制备了聚左旋乳酸-三亚甲基碳酸酯（PLLA-TMC）和聚右旋乳酸-三亚甲基碳酸酯（PDLA-TMC）无规共聚物.利用共聚物中PLLA/PDLA链段形成立构复合体,通过溶液浇注法制备了PLLA-TMC/PDLA-TMC立构复合聚乳酸材料（sc-PLA-TMC）.研究结果表明,聚合物链中的柔性TMC单元可以增强L（D）LA链段的运动能力,有助于不同旋光性的LA链段形成立构复合晶体,但也使得L（D）LA链段的规整度和序列长度降低.即随着共聚物链段中柔性TMC单元摩尔含量的增加,sc-PLA-TMC中同质结晶能力降低.当TMC含量≥5%时,仅生成熔点〉200℃的PLLA/PDLA立构复合结晶,表明sc-PLA-TMC的耐热性有所提高.蛋白酶K降解实验表明,PL（D）LA-TMC共聚物的降解速率不但比PLLA高,而且可通过共聚物中TMC含量进行调控.

英文摘要：

A series of copolymers with high molecular weight（ Mn 〉1 × 105） based on 1,3-trimethylene carbonate（ TMC） and L-lactide（ L-LA） or D-lactide（ D-LA） was synthesized by ring-opening polymerization using stannous octoate as catalyst. Then the stereocomplex sc-PLA films were prepared by mixing equal amount of the corresponding PLLA-TMC and PDLA-TMC solution and followed by solution casting. The chemical structure,thermal properties and enzymatic degradation behavior of sc-PLA films were characterized respectively. The results show that crystallinity of homochiral crystals in sc-PLA-TMC samples decreases with the increase of TMC content. Only stereocomplex crystals exist in sc-PLA-TMC samples when TMC contents beyond 5%. The enzymatic degradation results show that the degradation rate of samples is accelerated when TMC unit is introduced.