Crystallization Behavior of Polypropylene with or without Sodium Benozte as a Nucleating Agent

摘要

The crystallization kineics of polypropylene (PP) with or without sodium benzoate as a nucleating agent were investigated by means of DSC and polarized optical microscopy in isothermal and nonisothermal modes. A modified Avrami equartion was applited to the kinetic analysis of isothermal crystallization. The addition of the nucleating agent up to its saturation concentration increased the crystallization temperature by 15 deg C and shortended both the isothermal and nonisothermal crystallization half-times. It was concluded that the sodium benzoate acted as a good nucleating agent for #alpha#-form PP. By adding the nuclefier to PP, adequately controlled spherulites increased the mechanical properties including especially the Izod impact streng and shortened cycle time of PP.