Core-shell Structure Wood Plastic Composites with Inorganic Filler filled Shells: Thermal Expansion and Flexural Properties

摘要

Co-extruded wood plastic composites (WPCs) represent an important class of engineering materials. In recent years, extensive efforts have been devoted to the core-shell profiles since the core-shell structure composites as a new composite system have many advantages in emerging applications1. A talc-reinforced plastic component is typically of a thin "shell" construction, sometimes filled on the inside with structural foam, as in the case of surfboards. The component may be nearly arbitrary shape, limited only by the complexity and tolerances of the mold used for manufacturing the shell. Talc is a metamorphic mineral resulting from the metamorphism of magnesium minerals such as serpentine, pyroxene, amphibole, olivine, in the presence of carbon dioxide and water. Talc with a plate-like structure is one of the most commonly used fillers in plastic-based composites2. Furthermore, talc is among the most commonly used fillers for HDPE reinforcement as the shell layer especially for engineering applications 3,4 due to plastic shell leads to the reduced mechanical properties for WPCs. It has been shown that such filler particles increase Young’s modulus of composites, yet causing the decrease of the strength and the toughness. To optimize the advantage properties of inorganic fillers reinforced polymers composites, talc as fillers has been reported. For instance, Weon and Sue5 studied mechanical properties of talc and CaCO3-reinforced high-crystallinity polypropylene (HCPP) composites, and observed that a larger affection to improve the toughness and stiffness of HCPP systems to replace glass fiber-reinforced PP for engineering applications. More importantly, the improvement of tensile modulus can be observed in PP/talc composites.