Mechanical Behaviour of Sorghum Stalk Rind Reinforced Maleic Anhydride Grafted Polyethylene under Different Environmental Conditions

This work investigates the mechanical and service behaviour of high-density polyethylene composites reinforced by sorghum stalk rind (SSR) at various concentrations of fibres and maleic anhydride treated polyethylene (MAPE). Fibre length l and aspect ratio l/w distributions of compounded fibre composites show large numbers of smaller particles. Tensile and bending properties were investigated, taking the effects of some service conditions into consideration, such as water absorption and UV exposure. Untreated polyethylene reinforced with 40 wt.% SSR showed a maximum water uptake of 6.9 wt.%. Generally, reductions in strength and modulus were observed upon immersion in water. In contrast, UV radiation did not show any significant effect on mechanical properties at exposure times of up to 300 h.