Effect of birch wood flour on the density, water absorption, thickness swelling, and thermal conductivity of wood thermoplastic polyurethane composites

Abstract

In this study, some of the important properties of experimentally manufactured wood thermoplastic polyurethane composites were determined. Specimen having 30%, 40%, 50%, and 60% wood flour were mixed with rigid polyurethane foam. Physicalproperties (density, water absorption, and thickness swelling) and thermal conductivity of wood–plasticcomposites (WPC) were investigated. Results indicated that the density of WPCs decreased by increasing wood flour content. The results also revealed that water absorption and thickness swelling of the composites increases with increasing the percentage of wood flour content. It was found thatthermalconductivity of the composites slightly increased with the increasing of wood flour content. Experimental results of thermal conductivity were compared with a theoretical model (Maxwell – Garnett model), the errors associated with the above model, with respect to experimental ones, varies between 40% to 50%.