Effect of Grafting with Maleic Anhydride on Interfacial Bonding of Rubber Wood Flour Filled Poly(propylene) Composite

Summary The process of making wood-plastic composites with poly(propylene) as a matrix and rubber wood flour with particle size of 0.709 mm as a filler has been carried out by combination of the dry blending method and the extrusion treatment using twin screw extruder. The content of rubber wood flour was adjusted as 10wt% for each composite formula. Maleic anhydride grafted poly(propylene) (PP-g-MA) was added as a coupling agent at four concentrations, 0, 5, 10 and 15 wt%. Melt flow rate (MFR), crystalisation temperature and mechanical properties of composites indicate that increase in PP-g-MA generated decrease in melt viscosity significantly, which reversed MFR is increased, while mechanical properties increased due to interfacial bonding improved. Based on the differential scanning calorimetric analysis it was found that the mechanical properties and crystallization temperature increased with increasing PP-g-MA content, due to increase in interfacial bonding between matrix and sawdust fillers. In addition, fracture surface imaging analysis showed that good adhesion was present in the interface of composites between 10wt% and 15wt% PP-g-MA.