Recycled Thermoplastic–Woodflour Composites

Abstract

In the present study, composite materials were prepared from recycled PE, PP and commingled plastics, and waste cellulosics, e.g., sawdust (woodflour) of maple wood. In order to establish the compatibility, the woodflour was surface modified by precoating with maleated thermoplastics. Moreover, to improve the fire-retardancy, and at the same time to minimize the degradation of recycled plastics and woodflour various flame-retardant/heat-resistant/antioxidant materials (e.g., boric acid, Na-borate, Mg(OH)₂ and irganox) were incorporated in the composites during processing. The variation in mechanical properties, e.g., tensile strength, tensile toughness, elongation at break and Young's modulus, on the concentration of both unmodified and modified woodflour in compression molded composites has been evaluated. The effect of particle size, e.g., mesh sizes 40, 60 and 100, of the woodflour on the performance of the composites has also been evaluated. Experimental results indicate that mechanical properties of the modified woodflour-filled composites are generally higher than those of unmodified ones. Properties also change with the concentration and particle size of woodflour, and the nature of recycled plastics.