PBAT/滑石粉复合材料的非等温结晶动力学研究

Study on Non-Isothermal Crystallization Kinetics of PBAT/talc Powder Composites

利用差示扫描量热法结合Avrami方程研究聚对苯二甲酸己二酸丁二醇酯(PBAT)和聚对苯二甲酸己二酸丁二醇酯/滑石粉复合材料(PBAT/talc)的非等温结晶动力学,根据Avrami方程的Jeziorny法和莫志深法对数据进行处理,并利用Kissinger法计算PBAT及其复合材料的非等温结晶活化能。结果表明:适量的滑石粉在PBAT基体中可起到异相成核作用,提高了PBAT的结晶温度和结晶速率,使晶粒尺寸减小;当talc质量分数为20%时,复合材料的结晶速率最快,非等温结晶活化能绝对值最大;但当talc含量过多时,复合材料熔体黏度明显增大,PBAT分子链运动受阻,进行规整有序排列的速度减小,导致结晶速率和非等温结晶活化能绝对值下降。

The non-isothermal crystallization behavior and kinetics of PBAT,PBAT/talc powder composites was studied by differential scanning calorimentry combined with the Avrami equation.The modified Avrami theories of Jeziorny and Mo's method were used to analyze the data.The activation energy of non-isothermal crystallization of PBAT and PBAT/talc powder composites were calculated by Kissinger's method.The results showed that proper talc powder had the effect of heterogeneous nucleation in crystallization,increased the crystallization temperature and crystallization rate of PBAT,and decreased the grain size.When the mass fraction of talc powder were 20%,the crystallization rate and absolute value of non-isothermal crystallization activation energy reached the highest value.However,when the talc content is too high,the melt viscosity of the composites increases significantly,the movement of the PBAT molecular chain is blocked,and the speed of regular and orderly arrangement decreases,resulting in a decrease in the crystallization rate and the absolute value of non-isothermal crystallization activation energy.