Effect of fibre surface modification on water-sorption characteristics of oil palm fibres

Natural fibres have proved to be an excellent reinforcement in polymers. The main disadvantage of the natural fibres to be used as reinforcement in polymers for structural applications is their hydrophilic nature. Oil palm fibres have been found to be an excellent reinforcement in phenolic matrices. A detailed investigation on the water sorption characteristics of oil palm fibres has been carried out. Various fibre surface modifications such as mercerization, latex coating, gamma irradiation, silane treatment, isocyanate treatment, acetylation and peroxide treatment were tried to reduce the hydrophilicity and thereby decreasing the sorption characteristics. The effects of treatments on the sorption characteristics of oil palm empty fruit bunch fibre in distilled water at four different temperatures were investigated. Changes in physical and chemical modifications of fibres upon different treatments changed the water sorption behaviour. Treatment reduced overall water uptake at all temperatures. Hydrophilicity of the fibres decreased upon many modifications, which decreases water uptake. The effect of sorption on the mechanical performance of the treated and untreated fibres was also investigated. It was found that the mechanical properties of the fibres decrease upon sorption and regains on desorption.