Effect of different compatibilizing agents on the mechanical properties of lignocellulosic material filled polyethylene bio-composites

The tensile and Izod impact strength properties of lignocellulosic filler reinforced polyethylene bio-composites, made using low- and high-density polyethylene as the matrix polymer, rice-husk flour and wood flour as the reinforcing filler and different compatibilizing agents, were examined by assessing their mechanical properties and the morphological characteristics of their fracture surfaces. Test samples made with two different compatibilizing agents were injection molded, in order to determine their mechanical and morphological properties. The tensile strengths of the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were superior to those of the bio-composites fabricated using maleated polypropylene, due to the improved wetting of the former compatibilizing agent in the matrix polymer. Based on the results of the Izod impact strength tests, the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were also toughened. The SEM micrographs revealed a certain number of pulled-out traces on the fracture surfaces of the test samples fabricated using maleated polypropylene as the compatibilizing agent, but no pulled-out traces and many broken fillers on the fracture surfaces of the test samples fabricated using maleated polyethylene as the compatibilizing agent, due to the stronger interfacial bonding.