后聚合直接法制备聚L-乳酸的研究

Study of Synthesis of Poly(I-lactic acid) by Postpolymerization on Direct Method

L-乳酸预聚物在SnCl_2·2H_2O和对甲苯磺酸双催化体系下,用直接法熔融后聚合合成聚乳酸,研究了后聚合反应时间、预聚物相对分子质量等因素对聚合产物的影响,采用核磁及粘度计法测定聚合物相对分子质量,通过红外、核磁、X-射线衍射等手段对聚合物进行了表征及测试,表明在适宜的工艺条件下,熔融后聚合直接法合成较高相对分子质量的聚L-乳酸是可行的。

Prepolymer of L-lactic acid is catalyzed by a tin chloride dihydrate/p-toluenesulfonic acid binary system. In this process, We study the synthesis of poly(l-lactic acid) by postpolymerization on direct method. The properties and structure of products were characterized by NMR, IR, DSC, X-ray diffraction and so on. The results show that high molecular weight poly(l-lactic acid) can be prepared by Postpolymerization on Direct Method at suitable technological conditions.