Investigation of the Tensile Properties of Coir Fibre-Reinforced Polyethylene Composites for Agricultural Equipment Components

Coir fibre, derived from coconut husk, is an abundant agricultural by-product in coastal states of South South Nigeria, with considerable potential as a reinforcement material for low-cost polymer composites used in agricultural equipment. This study investigates the tensile properties of coir fibre-reinforced linear low-density polyethylene composites fabricated with fibres sourced from Bayelsa State. Coir fibres were subjected to alkali treatment using 6 percent sodium hydroxide solution for periods of 2, 4, and 6 hours, and composites were prepared by compression moulding at fibre contents of 10, 20, and 30 percent by weight. Tensile strength, elongation at break, Young's modulus, and energy to fracture were determined following ASTM D638 testing protocols. Morphological analysis was performed using scanning electron microscopy to assess fibre-matrix interfacial characteristics. Results indicate that fibres treated for 4 hours achieved optimal surface cleaning and fibrillation, producing composites with tensile strength of 21.6 MPa at 20 percent fibre content, representing a 34 percent improvement over untreated fibre composites. Elongation at break declined with increasing fibre content, reflecting the reinforcing effect and associated stiffness increase. Scanning electron microscopy confirmed improved interfacial bonding for treated fibres, evidenced by reduced fibre pull-out voids on fracture surfaces. The study demonstrates that coir fibre-polyethylene composites are mechanically suitable for low-load agricultural equipment components such as seedling trays, irrigation fittings, and tool handles. Recommendations include exploring compatibiliser addition for further interfacial property enhancement in South South Nigeria. Keywords: coir fibre, polyethylene composite, alkali treatment, tensile properties, agricultural equipment