Subsequent melting behavior after isothermal crystallization at different temperatures from the isotropic melt and nonisothermal crystallization kinetics and morphology of partially melting sPB were carried out by differential scanning calorimetry (DSC), polarized light microscopy (POM), respectively. Triple melting-endothermic peaks were observed for the polymer first isothermally crystallized at temperatures ranging from 141 to 149 degrees C, respectively, and then followed by cooling at 10 degrees C/min to 70 degrees C. Comparing with the nonisothermal crystallization from the isotropic melt, the nonisothermal crystallization for the partially melting sPB characterized the increased onset crystallization temperature, and the sizes of spherulites became smaller and more uniform. The Tobin, Avrami, Ozaxva, and the combination of Avrami and Ozawa equations were applied to describe the kinetics of the nonisothermal process. Both of the Tobin and the Avrami crystallization rate parameters (K-T and K-A, respectively) were found to increase with increase in the cooling rate. The parameter F(T) for the combination of Avrami and Ozawa equations increases with increasing relative crystallinity. The Ziabicki's kinetic crytallizability index G(Z) for the partially melting sPB was found to be 3.14. The effective energy barrier A/E describing the nonisothermal crystallization of partially melting sPB was evaluated by the differential isoconversional method of Friedman and was found to increase with an increase in the relative crystallinity. At the same time, Hoffman-Lauritzen parameters (U and K-g) are evaluated and analyzed from the nonisothermal crystallization data by the combination of isoconversional approach and Hoffmar Lauritzen theory. The K value obtained from DSC technique was found to be in good agreement with that obtained from POM technique. (c) 2006 Wiley Periodicals, Inc.