Role of moisture on press formed products made of Wood Plastic Composites

Abstract Press forming offers a feasible and sustainable post-production method to utilize wood plastic composite(WPC) materials made of recycled raw materials. The effect of moisture has been validated in the research of WPC material fabrication and pre-processing. However, inspection of the effect in post-processing of the material has been limited. This article investigated the effects of 30 days submersion of extruded WPC (50% wood/50% HDPE) material sheets and press-formed products under water. Before this investigation, a number of the sheets were reheated before submersion. The submersion results indicated significant differences in volumetric swelling and weight gain of reheated material sheets in comparison to non-reheated sheets and press formed products. The products and non-reheated sheets were significantly less absorptive and their dimensional stability was better compared to reheated material sheets.