Structure and properties of irradiated HDPE high-density polyethylene/calcium carbonate composites

Abstract

First, some groups of C=O and C–O were introduced onto high-density polyethylene (HDPE) chains by ultraviolet irradiation for short time in ozone atmosphere. The content of the groups was increased with increasing the irradiation time. The irradiated HDPE was blended with calcium carbonate (CaCO3) to prepare the composites. The melting temperature and crystallinity of HDPE in irradiated HDPE/CaCO3 composites were lower than the HDPE in HDPE/CaCO3 composites. Compared with the HDPE/CaCO3 composites, the dispersion of CaCO3 and the interfacial interaction between CaCO3 and HDPE in the irradiated HDPE/CaCO3 composites increased respectively. With increasing the irradiation time, the mechanical properties (especially impact strength) of the irradiated HDPE/CaCO3 composites were markedly enhanced, while their thermal stability decreased slightly. For example, the tensile strength and impact strength of the irradiated (20 min) HDPE/CaCO3 composites increased from 25.7 MPa and 72 J m−1 to 30.3 MPa and 416 J m−1, respectively, compared with those of the HDPE/CaCO3 composites, and stiffened and toughened HDPE composites were obtained.