Effect of OPEFB Size on the Mechanical Properties and Water Absorption Behaviour of OPEFB/PPnanoclay/PP Hybrid Composites

In recent years, lignocellulosic fibres are increasingly used as reinforcements in many thermoset and thermoplastic matrices for the production of low-cost and lightweight materials to be used as building materials, automotive components and consumer goods due to the environmental concern. In this study, polymer composites were prepared using oil palm empty fruit bunch (OPEFB) fibre at four different sizes (180 μm, 250 μm, 300 μm, and 355 μm) as the secondary filler that was added in the clay and Polypropylene mixture as their matrix. XRD was employed to investigate the presence of clay structure in composites. Meanwhile Flexural and impact tests (both notched and un-notched) were performed according to ASTM D790 and D256 to assess their mechanical performances. Results show that the increase of OPEFB fibre size has increased it flexural strength and modulus at smaller OPEFB fibre size. However a decrease of both flexural strength and flexural modulus was observed at higher OPEFB fibre size, which is believed due to the poor interfacial bonding between OPEFB and matrix. Meanwhile the impact strength for notched samples has slightly increased with the increase of OPEFB size and no increase was observed for the impact strength of un-notched composites. As expected the increase of OPEFB fibre size has increased the water absorption capability of composites mainly due to the hydrophilic nature of OPEFB fibres. Finally, observation on the fracture surface of samples using scanning electron microscope indicates that the OPEFB fibre treatment has improved the interfacial bonding between OPEFB fibre and matrix.