Abstract:
The materials utilized for this research include polyester resin, cobalt naphthanate - accelerator, methyl ethyl ketone peroxide (MEKP) - Catalyst and polyvinyl alcohol (PVA) - mould releasing agent which were all sourced locally. Rice husk were obtained from a rice mill located at Igbemo-Ekiti ,Ekiti State for use in the processing of the reinforcing filler (ash) for the production of the composite. The rice husk ash (RHA) was produced by burning the rice husk using a simple metallic drum with perforations to aid combustion. The ash obtained from the burning process was heat-treated at a temperature of 500oC for 240 minutes to reduce its carbonaceous and volatile constituents. Sieving of the rice husk ash was then performed using a sieve shaker to obtain ashes with mesh size of 50μm. Open moulding method was used to develop the rice husk ash reinforced polyester hybrid composite test samples. The process started with the determination of the quantities of rice husk ash (RHA) required to produce 2, 4, 6, 8 and 10wt% reinforcements (in the composite). The determined quantities of the polyester resin, RHA particles were measured on an electronic weighing balance with tolerance of ±0.001/g. The determined quantity of polyester resin, methyl ethyl ketone peroxide (MEKP) and cobalt naphthanate were poured into a beaker and stirred with a rod manually to achieve homogenization. Thereafter, the reinforcing ash was added and stirred for few minutes until even dispersion was achieved. The mixture was cast into already prepared aluminum moulds with cavities of tensile and flexural test specimen configurations. The mixture was left in the mould to cure before removal. Tensile and flexural tests was carried out on the produced samples. The results show that the open mould casting method adopted for the production of the composites was reliable. It was revealed that the composite grade of 8% rice husk ash gave the best tensile properties of all the composites produced. It was deduced that the composite grade of 8 % and 10 % rice husk ash gave the best flexural properties of all the composites produced
