Feasibility and properties of flat-pressed three-layer bamboo-rubberwood particleboards for resource-efficient production

This study aimed to develop new composites and evaluate the physico-mechanical properties and formaldehyde content of flat-pressed three-layer particleboard (FPTP) made of bamboo (as a face material) and rubberwood (as a core material) residue bonded with urea-formaldehyde adhesive. Different ratios of core and face material were adopted to investigate the effects of these ratios on the properties of the particleboards. The results indicate that increasing the proportion of rubberwood particles enhanced mechanical properties. All particleboards complied with the maximum permissible thickness swelling percentage (12%) specified in IS 3087 (2005) for Grade 2 category boards. While the moduli of rupture and elasticity values increased with higher rubberwood content, the particleboards did not satisfy the IS 3087 (2005) standard overall. However, the internal bonding strength of T4 (0.5 N/mm2) met the minimum requirement. Nail and screw withdrawal resistance of the particleboards indicated significantly higher resistance with increased rubberwood proportion. Only T4 particleboards met the minimum requirement stipulated by IS 3087 (2005) regarding screw withdrawal resistance for both Grade 1 and Grade 2 category boards. All boards met the criteria for the E2 classification (formaldehyde content ≤ 30 mg/100 g for oven-dried boards).