微胶囊化聚乙二醇非等温结晶动力学研究

Study on non-isothermal crystallization kinetics of microencapsulated polyethylene glycol particles

采用微胶囊化的方法制备出聚乙二醇(PEG)微胶囊粒子,研究其在三维受限条件下的非等温结晶行为。微胶囊化后的Avrami指数(n)小于未微胶囊化颗粒;未微胶囊化体系中,n随相对分子质量增加而增大,而微胶囊化后,n随相对分子质量的增加而减小;n在微胶囊化前后都随降温速率的降低而增大。

The microencapsulated polyethylene glycol （PEG） particles were prepared with the microencapsulation process for the purpose of studying its non-isothermal crystallization behaviors under three-dimensional restricted condition. The results show that the Avrami exponent of the microencapsulated PEG particles is smaller than that of the non-microencapsulated PEG particles. The Avrami exponent in the non-microencapsulated system decreases while the identical exponent in its microencapsulated counterpart increases as the relative molecular mass rises. However, the Avrami exponent always augments with lowering cooling rate no matter before or after microencapsulation.