Dimensional stability and strength properties of wood plastic composites produced from sawdust of Cordia alliodora (Ruiz and Pav.)

Abstract

This study evaluates the effects of densities and mixing ratio on the physical and mechanical properties of wood plastic composites boards at mixing ratio of 1:1 to 1:1.4 and nominal densities of 700kg/mm3 and 800kg/mm3. The quantity of High Density Polyethylene (HDPE) and saw dust used in the production of Wood Plastic Composites (WPCs) was weighed to a nominal density of 700kg/mm3 and 800kg/mm3. The materials were thoroughly mixed and fed into a neatly primed oil mould with a dimension of 300 x 300 x 10 mm. Test samples used for physical and mechanical properties determination were collected from each board produced from the mould. The results showed that WPCs board produced from mixing ratio 1:1 had the highest Modulus of Rupture (MOR) and Modulus of Elasticity (MOE) values of 6.52 mm N-2 and 564.95 mm N-2 respectively. Water absorption, thickness swelling and linear expansion of WPCs produced from wood/plastic ratio of 1:1.4 had the lowest mean values of 6.67, 0.83, 0.68% and 21.61, 1.33, 5.35% respectively after 2 hours and 24 hours of water immersion test. Analysis of variance carried out at 0.05% probability level showed that the effect of density and mixing ratio were significant on the physical and mechanical properties of wood plastic composites boards.