Water Absorption Properties of Kenaf/Glass Reinforced Unsaturated Polyester Composites used in Insulator Rods

Abstract

Kenaf fibres have acquired enormous attention in recent years, owing to their economic viability and environmental acceptability. Kenaf (natural) fibres have been started to replace the glass fibre (synthetic) in mechanical, electrical applications and have been utilized in several applications of industrial engineering. The current study deals with water absorption of kenaf/glass fibre reinforced unsaturated polyester composite materials used in high voltage polymeric insulator rods. The kenaf/glass hybrid composites were based on 20%, 30% and 40%(by volume) of kenaf fibers replacement glass fibres with modified 60 vol.% unsaturated polyester resins. The composites were immersedin distilled water at room temperature, and composites resistance to water absorption in terms of the rate of water absorption was determined.A considerable difference in the properties of water absorption of the hybrid composite was found demonstrating that the water absorption effect on the characteristics of insulator rods depends on the arrangement and volume fraction of kenaf fibre of the composite used. Based on the results obtained, a slight effect of water absorption on pure glass fibre composite (control) was observed. The addition of kenaf fibre on glass fibre composite rod increased the water absorption of the composite. It was shown that glass fibres surrounding kena ffibre reduced water absorption. Despite the fact that 40 vol.% of kenaf fibre composite had the highest natural fibre content, it showed the lowest water absorption because of its arrangement on all composite diameters, and also because of being surrounded by glass fibres. All of the materials reached equilibrium and ceased to absorb water after 300 hours.