Papers by Author: J.C. Nwachukwu

Abstract: Study was carried out to develop a composite material from agro waste consisting of sawdust and palm kernel shell and to determine its physical and mechanical properties. The sawdust / palm kernel shell compositions by weight were in the ratios of 100: 0, 90: 10, 80: 20, 70: 30, 60: 40 and 50:50. Urea formaldehyde was used as the test binder at concentrations of 20% of oven dry weight of agro waste. Particle size of agro waste used was 300µm .Yield strength, ultimate tensile strength, modulus of elasticity, modulus of rupture, internal bond strength, density, thickness swelling and water absorption of the formed composite materials were determined and observed to be enhanced at high palm kernel shell composition. The composite composition by weight that gave the best results out of the six compositions tested was the one with sawdust: palm kernel composition of 50%:50% with its properties as: yield strength ( 4.47 N/mm²) ,ultimate tensile strength (7.75 N/mm²), modulus of elasticity (2603 N/mm²), modulus of rupture (16.67 N/mm² ), internal bond strength ( 0.54 N/mm² ), thickness swelling (10.30%) ,water absorption (18.90%) and density (996.18kg/m³).

Abstract: The purpose of this study was to determine the effect of particle size on the mechanical properties (Modulus of Elasticity, Modulus of Rupture, and Internal Bond) and physical properties (thickness swelling and water absorption) of rice husk particleboard. The particle sizes used were 1.0mm, 1.18mm, 2mm, 2.36mm and 2.80mm. Each was mixed with a constant resin (urea formaldehyde) concentration of 20% of oven dry weight of rice husk particles. The results showed that as the particle size increased, the particleboard’s mechanical and physical properties decreased. For example, the modulus of elasticity, modulus of rupture, internal bond, thickness swelling and water absorption for 1.0mm particle size particleboard were 1590N/mm2, 11.11N/mm2, 0.28N/mm2,10.90% and 38.53% respectively, while for 2.8mm particle size they were 1958N/mm2,14.2N/mm2, 0.44N/mm2, 11.51% and 47.21% respectively. Overall results showed that particleboard made from rice husk exceed the EN standard for modulus of elasticity, modulus of rupture, internal bond. However, thickness swelling values were poor. Hence, the smaller the particle size the better the properties of the particleboard.