A simple method of evaluating non-isothermal crystallization kinetics in multicomponent polymer systems

A new simple method of evaluating non-isothermal crystallization kinetics is proposed. The procedure based on mathematical treatment of DSC cumulative crystallization curves at their inflection point provides three kinetic parameters: temperature of start of crystallization (T-s), temperature of maximum crystallization rate (T-i) and numerical value of the maximum crystallization rate (s(i)), and also final crystallinity after cooling (CRc). The method is demonstrated on the system poly(epsilon-caprolactone)/pol-y(lactic acid)/clay C15 and related microfibrillar composite. The method provides the values of T-s and T-i with standard deviation sigma = 0.3 and 0.4 degrees C, respectively. The coefficient of variation nu of s(i) and CRc is 5.8 and 1.5%, respectively. The proposed method does not refer to any crystallization model and does not require exact determination of the starting time. It is particularly useful for characterizing a series of samples derived by modification of the neat polymer. (C) 2015 Published by Elsevier Ltd.