Analysis of the Non-isothermal Crystallization Kinetics of the Polyamide 6/M-lignin Composites

Abstract

In this study, investigations of the non-isothermal crystallization kinetics of polyamide 6 (PA6) and PA6/m-lignin composites were conducted by differential scanning calorimetry (DSC). The crystallization kinetics of the PA6, including crystallization temperature and rate, were characterized by monitoring the heat flow during cooling. The study found that the crystallization temperature shifted to lower temperatures and the crystallization kinetics slowed down with increasing lignin. Besides, the Avrami equation modified by Jeziorny and Mo’s method were used to study the non-isothermal crystallization kinetics of the neat PA6 and PA6 composites. The curve fit resulting from the modified Avrami equation was not convincing. However, Mo’s method did successfully characterize the overall non-isothermal crystallization kinetics for neat PA6 and the PA6 composites. In addition, the activation energies of the non-isothermal crystallization were calculated by the Kissinger method. It was found that the PA6 composite crystallization rate increased when adding less than 10% lignin. However, the more the content of m-lignin, the slower the crystallization rate. The same conclusion was reached based on the fitting results of the non-isothermal crystallization activation energies.