尼龙-64的非等温结晶动力学研究

Study on Nonisothermal Crystallization Kinetics of Nylon-64

用差示量热扫描热分析仪(DSC)对在超临界CO2下聚合制备的尼龙-64样品进行了非等温结晶研究。用Jeziorny法和莫志深法对Avrami修正的方程进行了非等温结晶动力学处理,计算并得到了相关非等温结晶动力学参数。Jeziorny法处理的结果表明,尼龙-64样品的非等温结晶过程包括2个阶段,在主期结晶阶段,当冷却速率低于10℃/min时,Avrami指数n为3.59～4.12,表明主要是均相成核和晶粒三维增长;当冷却速率高于10℃/min时,晶粒的增长维度受阻;在次期结晶阶段,晶粒主要是一维增长。用莫志深法得到的a值为1.26～1.33,F(T)为6.35～13.02。此外,用Kissinger方法和Takhor方法求得尼龙-64样品的非等温结晶活化能分别为-192.05kJ/mol和-172.61kJ/mol。

The samples of nylon-64 that prepared under supercriticat CO2 are investigated by differential scan- ning calorimetry（DSC）. And its nonisothermal crystallization kinetics is studied using the Avrami equations modified by Jeziomy and Mo. Some important kinetics parameters are calculated and obtained. The results attained by Jeziorny method show that the nonisothermal crystallization kinetics of nylon64 includes two stages, in main crystallization stage, when the cooling rate under 10~C/min,the Avrami index （n） between 3.59 and 4. 12, which show most of the nucleations process are homogeneous and the three dimension growth of the crystal particles. And the growth of the crystal particles is restricted when the cooling rate exceeds 10℃/min. In the inferior crystallization stage, most of the growth of the crystal particles are the one dimension. The a value obtained by Mo method is from 1.26 to 1.33, and the F（T） is from 6.35 to 13.02. In addition, the activation energy of nonisothermal crystallization {or nylon-64 ob- tained by Kissinger method and Takhor method are --192. 05kJ/mol and --176.21kJ/mol, respectively.