有机金属磷酸盐/聚乳酸复合材料的非等温结晶动力学研究

Non-isothermal Crystallization Kinetics of PLLA/NA Composites

采用DSC对有机金属磷酸盐/左旋聚乳酸(NA/PLLA)复合材料的非等温结晶动力学进行了研究,并对所得数据用Jeziony方程进行了处理。结果表明有机金属磷酸盐(NA)能有效地提高PLLA的结晶度。NA对PLLA结晶过程的影响是成核效应和阻碍分子链的运动的协同作用,而且冷却速率的提升提高了添加剂对分子链的阻碍作用。Jeziony理论分析表明PLA及其复合材料的Avrami指数n均在2～3之间,前期PLA及PLA/NA复合材料可能以二维生长方式生长,而且NA的加入并未改变PLA的成核机理和生长方式。

The non-isothermal crystallization kinetics of PLLA/NA composites were studied by DSC. The Jeziorny equation was used to analyze the data. The results indicated that NA can increase the crystallization of PLLA. The effect of NA on the crystallization process of PLLA including nucleation effect and impeding chain diffusion, and the impeding effect was stronger when the cooling rate was higher. It was found that the values of Avrami parameternfor PLLA and PLLA/NA composites were in the range of 2 - 3, The results showed that the crystallization process developed two dimensional circular diffusion controlled growth, the adding of NA did not change the nucleating mechanism and grouping way.