Coconut fibres and laminates with Jabon trunk (Anthocephalus cadamba Miq.) veneer for hybrid plywood composites: dimensional stability and mechanical properties

Jabon wood (Anthocephalus cadamba Miq.) and coconut fibres currently appear to be the most viable raw material alternative in wood-based industries. This study examines the hybrid composites incorporating the Jabon trunk veneer and coconut fibres in a plywood product and analyses its properties. The samples were arranged into five-ply hybrid plywoods based on coconut fibre arrangements, comprising coconut woven fibre mats (HPWF) and coconut non-woven fibre mats (HPRF). Hybrid plywood with a thickness of 14 mm was cold pressed and hot pressed using urea formaldehyde (UF) and phenol formaldehyde (PF) resin, respectively. The dimensional stability and mechanical properties of the Jabon plywood and hybrid plywood composites were analysed. The hybridisation of coconut fibres with the Jabon trunk improved the dimensional stability and mechanical properties of plywood, such as its density, thickness swelling, bending, and screw withdrawal, especially for hybrid plywood using PF. Similarly, HPRF also demonstrated an increase in dimensional stability and mechanical properties. The weak bonding interface between the coconut fibre and formaldehyde matrix caused fibre-pull-out to happen in the hybrid plywood composite. The HPRF had better properties than HPWF. Statistical analyses show that coconut fibre arrangement of woven mats, and non-woven mats, and types of adhesive of UF, and PF did affect dimensional stability and mechanical properties, even though the interaction between the two did not affect density.