The Morphology and Tensile Strength of High Density Polyethylene/Nano-Calcium Carbonate Composites Prepared by Dynamic Packing Injection Molding

Abstract

In this article, dynamic packing injection molding (DPIM) was used to prepare pure high density polyethylene (HDPE) and its composite with nano-CaCO3 samples, whose mechanical properties were improved significantly. Compared with conventional injection molding (CIM), the enhancement of tensile strength of dynamic HDPE/ nano-CaCO3 samples are 122%. According to the SEM, WAXD, and DSC measurement, it was found that a much better dispersion of nano-CaCO3 was achieved by the technology of DPIM. More importantly, DPIM also caused an obvious increase in orientation of HDPE matrix. The crystallinity degree of HDPE in dynamic sample increased by 5.52% compared with a conventional one. The improvement in mechanical properties for dynamic HDPE/ nano-CaCO3 is attributed to the even distribution of nano-CaCO3 particles, the orientation of HDPE crystals, as well as increase of crystallinity degree under the influence of DPIM.