直接熔融聚合法制备生物降解材料PCEL

Direct Synthesis of Biodegradable PCEL by Melt Polycondensation

研究了直接熔融聚合法合成生物降解材料聚己内酯/聚乙二醇/聚乳酸三元共聚物(PCEL)的聚合工艺,分别讨论了原料投料比、催化剂种类及用量、聚合温度及时间等因素对共聚产物PCEL特性黏数的影响,确立了最佳的反应条件。在本实验条件下,最适宜的直接熔融共聚合工艺为：投料比为n(PEG)/n(ε-CL)/n(D,L-LA)=10/ 63/27；催化剂为氯化亚锡,用量为反应物质量的0．5%；在压力70 Pa、120℃下预聚合除水3 h后,再经180℃熔融共聚16 h。所合成的聚己内酯/聚乙二醇/聚乳酸(PCEL)共聚物的特性黏数[η]最高可达0．445 7 dL/g。

The direct synthesis technology for biodegradable polycaprolaetone/pelyethylene glycol/polylactide （PCEL） tri-component copolymer from lactic acid （D, L-LA）, ε-caprolactone （ε-CL） and polyethylene glycol （PEG, ^-Mn= 600）, by means of melt polycondensation was studied. The influences of material ratio, catalysts category and quality, polymerization temperature and time on the intrinsic viscosity of PCEL were studied, and the optimum reaction conditions were determined. PCEL with the highest intrinsic viscosity of 0.4457dL/g was produced by pre-condensed at 120℃ and 70Pa for 3h, then copolymerized at 180℃ and 70Pa for 16h by the catalysis of 0.5 % SnCl2 when the molar ratio of PEG/ε-CL/D, L-LA was 10/63/27.