Since several years ago, a biodegradable, and environmentally friendly materials for the next generation of composite materials have been developed due to worldwide environmental concerns. Kenaf fibres are widely available and relatively inexpensive compared to other natural fibres. Meanwhile, microcrystalline cellulose (MCC) has been used in wide range of applications, offers outstanding mechanical qualities, strong temperature resistance, and increased liquid stability. This research aimed to prepare the hybrid microcrystalline cellulose/kenaf core fibre reinforced unsaturated polyester resin biocomposites through the compressing molding technique. In this study, the effects of MCC loading with varying concentrations from 0.5 wt% to 3 wt% on mechanical and physical properties of KCF/UPE biocomposites were investigated. Overall, the flexural test revealed that incorporating MCC into KCF/UPE biocomposites decreased flexural strength and modulus. It was interesting to observe that, pure UPE resin demonstrated more higher mechanical properties than KCF/MCC reinforced UPE biocomposites.
Water absorption behaviour of the MCC-KCF/UPE biocomposites was also conducted for 168 hours. It has been shown that the water absorption percentage of biocomposites increases with increasing MCC content. The scanning electron microscopy (SEM) was conducted on the fracture surfaces of flexural test. The SEM study showed that, there are poor interfacial adhesion between KCF, MCC, and the UPE matrix. Fibre pull-out, cracks surface, gaps between fibre and matrix, and voids are some of the defects that have occurred when a load is applied to the specimen. Furthermore, the aggregations of reinforcements explain the poor mechanical properties.