Effects of Polyethylene-g-maleic Anhydride on Properties of Low Density Polyethylene/Thermoplastic Sago Starch Reinforced Kenaf Fibre Composites

摘要

Effects of polyethylene-g-maleic anhydride (PE-g-MA) as a compatibilizer on tensile properties and morphology of low density polyethylene/thermoplastic sago starch (TPSS)-kenaf fibre composites were studied. TPSS was prepared by mixing the starch (65 wt%) and glycerol (35 wt%) and storing it overnight at room temperature. The mixture was then melt-compounded using a heated 2 roll-mills at 150℃ for 20 min. LDPE/TPSS blend ratio was fixed at 80 wt% of LDPE and 20 wt% of TPSS. LDPE/TPSS-kenaf fibre composites with different fibre loadings, with and without the addition of PE-g-MA were prepared by using an internal mixer at 150°C. All mixings were carried out for 20 min at a rotor speed of 50 rpm. Tensile test specimens were cut out from the compression moulded sheets. Results indicated that the tensile strength and Young's modulus of LDPE/TPSS-kenaf fibre composites with the addition of PE-g-MA were greater than the composites without the addition of PE-g-MA particularly at higher fibre loading. The interfacial properties between LDPE, TPSS and fibre were improved after the addition of PE-g-MA as it is evident from the tensile surface fracture morphology using a scanning electron microscopy. Equilibrium water uptakes for LDPE/TPSS-kenaf fibre composites were higher than those of LDPE/TPSS-kenaf fibre composites with the addition of PE-g-MA due to lower abundance of hydrogen group.