Crystalline Form Transition in Isotactic Polypropylene with addition of N,N′‐diphenyl Succinamide

Abstract

N,N′‐diphenyl succinamide (DPS) is found to be an active β nucleating agent for iPP in this study. The effect of crystallization temperature and the content of N,N′‐diphenyl succinamide on the formation of β‐iPP have been investigated by wide angle X-ray diffraction (WAXD) and polarized light microscopy (PLM). The results of WAXD indicate that the relative proportion of β‐form (K‐value) reaches a maximum of 92.4% with the addition of 0.2 wt% N,N′‐diphenyl succinamide, and the optimal crystallization temperature for growth of the β form is 120°C. The images of PLM show that the sizes of β‐spherulites enlarge with increasing crystallization temperature. The cell parameters of DPS show good lattice matching with the β‐crystal form of iPP.