Crystallization behavior and melting characteristics of PP nucleated by a novel supported β-nucleating agent

Abstract

The β-nucleated PP with high β-PP content was prepared by a novel supported β-nucleating agent, which was prepared with pimelic acid supported on nano-CaCO3 as support. The influences of the content of the support and supported β-nucleating agent, pre-melting temperature (Tmelt) and scan rates on crystallization behavior and melting characteristics, and the β-PP content of β-nucleated PP were determined by Differential Scanning Calorimeter (DSC) and Wide-Angle X-ray Diffraction (WAXD). The results indicated that the addition of supported β-nucleating agent markedly increased the crystallization temperature (Tc) of PP. Increasing the content of supported β-nucleating agent slightly increased the Tc, but had no influence on the melting temperatures (Tm) of β-nucleated PP. The Tc and Tm of β-nucleated PP decreased slightly with increasing the content of the support nano-CaCO3. The effects of scan rates and multiple scans with different Tmelt on the crystallization and melting behavior of PP nucleated by supported β-nucleating agent are similar to that of PP nucleated by calcium pimelate (CaHA). The β-PP content above 90 percent was obtained in PP nucleated by supported β-nucleating agent and was not influenced by the content of nano-CaCO3. The supported β-nucleating agent prepared by supporting pimelic acid on nano-CaCO3 is a β-nucleating agent with high efficiency and selectivity, and low cost.