聚DL-乳酸的合成及其热性能研究

以辛酸亚锡为催化剂催化丙交酯开环聚合DL-乳酸(PDLLA)。研究了影响PDLLA分子量的因素包括丙交酯单体的纯度、催化剂的浓度、反应温度、反应时间及真空度等。用DSC，TGA分析了不同分子量PDLLA的警警化转变和热失重。结果表明，PDLLA是热不稳定聚合物，残留的单体、催化剂及低聚物是影响PDLLA热稳定性的因素，除去其中残留的单体、催化剂及低聚物可以提高PDLLA的热稳定性。

Synthesis and Thermal Capability Studying of Poly(DL-lactide)

Poly(DL-lactide)(PDLLA) was synthesized by the ring-opening polymerization of DL-lactide using staunous octoate as a catalyst. The factors affecting the PDLLA molecular weight were found to be the monomer purity, the catalyst concentration, the polymerization temperature, the polymerization time and the vacuum. The glass transition temperature and the thermal decomposition of PDLLA were determined by DSC and TGA. The results showed that PDLLA was a thermal unstable polymer. Reducing the residue of monomer, catalyst and oligomer can enhance the thermal stability of PDLLA.