Sandwich-structured wood flour/HDPE composite panels: Reinforcement using a linear low-density polyethylene core layer

Sandwich-structured panels, composed of two surface layers of wood flour/high-density polyethylene composite (WPC) and a core layer of linear low-density polyethylene (LLDPE), were prepared by hotpress. The single-layer WPC panels were used as controls, with wood flour contents ranging from 55 to 84%. The sandwich-structured panels showed an improvement in both flexural and impact strength of up to 42% and 77%, respectively, and water absorption was considerably reduced compared to the controls. The LLDPE core layer did not cause substantial change in creep and relaxation behavior, but resulted in an increase in the linear coefficient of thermal expansion. (C) 2017 Elsevier Ltd. All rights reserved.