Effeds of Coupling Agent on Mechanical Properties of Rice Husk Filled Polyethylene Composite

This project presented the experimental study of the effects of the coupling agents concentration on the mechanical properties of natural fibers reinforced composites such as tensile and flexural properties. The chosen natural fiber used in the project is rice husk flour (RHF), a type of agricultural waste. Based from previous research, RHF has good potential as reinforcement in thermoplastic composite. RHF was combined with high density polyethylene (HDPE) as the matrix to create the composite with the addition of maleic anhydride grafted polyethylene (MAPE) as a coupling agent. The concentration of coupling agent used in the compounding process of RHF and HDPE depended on the pre-determined compositions. The addition of the coupling agents were varied using the percentage varying from 0 wt.%, 2.5 wt.% 5 wt.%, 7.5 wt.% and 10 wt. %. Experiment parameters such as temperature and moisture content affected the results of the composite. The pallets produced from extrusion process below 200°C with screw speed 60rpm. The pallets produced were injection moulded at temperature around 185-200°C to produce specimens for the tensile tests (ASTM D638) and flexural tests (ASTM D790). Five good samples were used for each type of compositions of the composites for the tensile and flexural tests. Based from the conducted tests, it was found that the tensile strength of the composites when using the concentration of 5 wt. % of MAPE is the highest value. The highest value for flexural strength however found using only at 2.5 wt.% ofMAPE. ii