Toughening and reinforcement of HDPE/CaCO3 blends by interfacial modification?interfacial interaction

To improve the mechanical properties and structure of HDPE/CaCO3 composites, a type of modifier, consisting mainly of carboxylated polyethylene (CPE), and a type of CaCO3 grafted with acrylamide (CaCO3(SINGLE BOND)A) were used. The carboxyl group content of CPE was from 1 to 10%. The amide group content on the surface of the modified CaCO3 was from 0.2 to 1.8%. The interfacial structure and interaction of ternary blends of HDPE, CPE, and CaCO3(SINGLE BOND)A were studied. The results indicate that the higher the amide group content and the carboxyl group content, the higher the tensile and impact strength. This behavior has been attributed to a series of chemical and physico-chemical interactions taking place between the two components during the blending process which were confirmed by FTIR and extraction experiments. The improvement of interfacial adhesion by the CPE and CaCO3(SINGLE BOND)A was also clearly revealed in the SEM of the fracture surface.