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 (Ts), temperature of maximum crystallization rate (Ti) and numerical value of the maximum crystallization rate (si), and also final crystallinity after cooling (CRc). The method is demonstrated on the system poly(ɛ-caprolactone)/poly(lactic acid)/clay C15 and related microfibrillar composite. The method provides the values of Ts and Ti with standard deviation σ = 0.3 and 0.4 °C, respectively. The coefficient of variation v of si 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.