摘要
以L_乳酸单体为原料 ,通过熔融 -固相聚合法直接合成聚左旋乳酸 (PLLA) .筛选出SnCl2 为适宜的催化剂进行熔融聚合 ,聚合的最佳工艺条件为 :SnCl2 质量分数为0 .5 % ,180℃、70Pa下反应 10h .以熔融聚合制得的粘均相对分子质量为 5 0 0 0的PLLA为原料 ,于 6 0Pa下 ,以SnCl2 为催化剂进行变温固相聚合 (先在 135℃下反应 5h ,再在15 0℃下反应 10h) ,可使粘均相对分子质量提高到反应前的 5 .3倍 .
The appropriate conditions for the direct synthesis of poly( L _lactic acid) (PLLA) via melt_ solid polycondensation were studied with SnCl 2 as an optimal catalyst. The optimal reaction conditions for melt polycondensation were found, that is, 0.5%(mass fraction) SnCl 2, 180 ℃, 70 Pa and 10 h. In the following solid_state polycondensation, under absolute pressure 60 Pa with subsection temperature controlling (first at 135 ℃ for 5 h, then at 150 ℃ for 10 h), the viscosity_average relative molecular mass ( M η ) of PLLA could be 5.3 times higher than that of PLLA prepared only via melt polycondensation.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2002年第11期155-159,共5页
Journal of South China University of Technology(Natural Science Edition)
基金
广东省自然科学基金资助项目 (0 2 0 885 )
