苯乙烯-丙烯等规立构嵌段共聚物(iPS-b-iPP)的非等温结晶动力学的研究

用DSC法研究了苯乙烯-丙烯等规立构嵌段共聚物的非等温结晶动力学。结果表明:冷却速率在5～20℃/min范围内,共聚物的非等温结晶动力学参数能很好地符合Avrami动力学方程,非等温结晶速率常数与冷却速率有关,动力学结晶能力则同时受到冷却速率和共聚物组成比的影响。文中还讨论了在非等温结晶条件下共聚物的结晶成核和生长方式与共聚物组成和结构的关系。联合Avrami方程和Ozawa方程推导的非等温结晶动力学方程较好地描述了iPS-b-iPP嵌段共聚物的非等温结晶动力学过程。

Studies on Non-Isothermal Crystallization Kinetics of iPS-b-iPP Block Copolymer

The non-isothermal crystallization kinetics of iPS-b-iPP block copolymers has been investigated by DSC.The results based on the Jeziorny's method show that in the range of cooling rate of 5 to 20℃/min, the kinetics of non-isothermal crystallization for all of samples is fitted for the Avrami equation quite well. The crystallization rate constant Z_crelates to the cooling rate, whereas the specific crystallizability G_cis dependent upon both the cooling rate and composition ratio of iPS-b-iPP copolymers.In addition, a discussion about the relationship between the growing mechanism of crystals and the composition ratio of iPS-b-iPP copolymers was made based on the Avrami exponents. Anew kinetics equation of non-isothermal crystallization derived by combining Avrami and Ozawa equation was proved to fit for kinetics of non-isothermal crystallization of iPS-b-iPPcopolymers.