Effects of Sawdust Content and Alkali Treatment on Mechanical and Flame Retarding Properties of Sawdust/Recycled High Density Polyethylene Composites

Abstract

Sawdust/recycled high density polyethylene (rHDPE) composites were prepared and their mechanical properties, flammability and morphology were investigated. Sawdust was used at contents of 30, 40 and 50 wt%. With increasing sawdust content, tensile strength and elongation at break of the composites decreased whereas tensile modulus increased. Flexural properties showed the same trend as tensile properties. Flammability of the composites enhanced with increasing sawdust content. Mechanical properties of alkali treated sawdust/rHDPE composites were higher than those of untreated sawdust/rHDPE composites at all sawdust contents. Moreover, alkali treatment improved flame retardancy of the composites. SEM micrographs showed that alkali treatment enhanced the interfacial adhesion between sawdust and rHDPE matrix.