Effects of LENR addition on mechanical properties of kenaf fibre reinforced epoxy composites

Effects of liquid epoxidized natural rubber (LENR) on the mechanical behaviour of kenaf fibre reinforced epoxy composite were studied. Kenaf fibres (Hibiscus cannabinus, L. family Malvaceae) and thermoset matrices were hand-laid up and characterized in terms of its mechanical properties. The objective of this research is to investigate the effect of LENR to the flexural and impact properties of the kenaf fibre reinforced epoxy composites. The fibres were alkali treated before use as reinforcement in the epoxy resin matrix. Five different fibre concentrations of 5%, 10%, 15%, 20% and 25% by weight have been used (with and without addition of liquid epoxidized natural rubber). Flexural, impact and DMTA tests of rubber toughened epoxy reinforced kenaf fibre composites were performed. The fractured surfaces of these composites were investigated by using scanning electron microscopic technique (SEM) to determine the interfacial bonding between the matrix and the fibre reinforcement. It was found that the addition of LENR increased the flexural strength, flexural modulus and impact strength by 17.6%, 11% and 47% respectively.