Influence of Meranti sawdust aspect ratios and amount of loadings on mechanical and morphological properties of composites from polypropylene and Meranti sawdust

This research focused on the mechanical and morphological properties of polypropylene composites reinforced by Meranti hardwood sawdust. The effects of sawdust aspect ratio (L/D ratio), the amount of the sawdust and the application of maleic anhydride-grafted-polypropylene (MAPP) coupling agent on the composite properties were also investigated. Composites were prepared by compounding in a single-screw extruder, then, injection moulding technique was used to obtain testing specimens. It was found that Young’s modulus and flexural modulus of the sawdust-polypropylene composites were increased prominently with the increasing of not only the sawdust aspect ratio but also the % sawdust content. Besides, impact strength was depended on the sawdust aspect ratio. In addition, the use of the MAPP coupling agent had a profound effect on the mechanical properties of the composites. Micrographs from scanning electron microscope (SEM) revealed the improvement of adhesion in the interfacial boundary between the sawdust and the polypropylene matrix.