Authors: Shaohui Wang Weibing Xu Zhengfa Zhou Fengmei Ren
Publish Date: 2010/02/06
Volume: 25, Issue: 1, Pages: 12-19
Abstract
The nonisothermal crystallization kinetics of polypropylene PP PP/anhydrite composites were investigated by differential scanning calorimetry DSC with various cooling rates The Avrami analysis modified by Jeziorny and a method developed by Mo were employed to describe the nonisothermal crystallization process of these samples The difference in the exponent n between PP and PP/anhydrite composites indicated that nonisothermal kinetic crystallization corresponded to tridimensional growth with heterogeneous nucleation The values of halftime Z c and FT showed that the crystallization rate increased with the increasing of cooling rates for PP and PP/anhydrite composites but the crystallization rate of PP/anhydrite composites was faster than that of PP at a given cooling rate The method developed by Ozawa did not describe the nonisothermal crystallization process of PP very well Moreover the method proposed by Kissinger was used to evaluate the activation energy of the mentioned samples The result showed that the activation energy of PP/anhydrite was greatly larger than that of PP
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