【摘 要】
：
以L-和D,L-乳酸为原料熔融缩聚制备聚乳酸,采用旋光度法1、H核磁共振法和13C核磁共振法和X-射线衍射等方法研究催化剂对聚乳酸微结构的影响。D,L-乳酸采用非立构选择性催化剂
【机 构】
：
南京林业大学化工学院,南京林业大学图书馆技术部,
论文部分内容阅读
以L-和D,L-乳酸为原料熔融缩聚制备聚乳酸,采用旋光度法1、H核磁共振法和13C核磁共振法和X-射线衍射等方法研究催化剂对聚乳酸微结构的影响。D,L-乳酸采用非立构选择性催化剂萘磺酸缩聚时,所得的聚乳酸为消旋的非晶态聚合物。而采用SnCl2/对甲苯磺酸和SnCl2/萘磺酸等立构选择性催化体系时,D,L-乳酸缩聚所得的聚乳酸是L-构型为主的结晶聚合物,且SnCl2/萘磺酸体系的聚乳酸具有更高的光学活性。采用不同催化剂,D,L-乳酸可缩聚制备不同结构和性能的聚乳酸。
Poly (lactic acid) was prepared by melt polycondensation of L- and D, L-lactic acid. The effects of catalyst on the microstructure of polylactic acid were investigated by optical rotation method (1H NMR), 13C NMR and X-ray diffraction. D, L-lactic acid non-stereoselective catalyst naphthalene sulfonic acid polycondensation, the resulting polylactic acid racemic amorphous polymer. In the case of stereoselective catalytic systems such as SnCl2 / p-toluenesulfonic acid and SnCl2 / naphthalene sulfonic acid, polylactic acid obtained by polycondensation of D, L-lactic acid is a L-configuration-based crystalline polymer and SnCl2 / Acid system of polylactic acid has a higher optical activity. Using different catalysts, D, L-lactic acid polycondensation to prepare different structures and properties of polylactic acid.
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