Properties of Medium Density Fibreboard Manufactured from Extracted and Unextracted Acacia Catechu Wood Chips

Abstract

The project was carried out to evaluate the properties of medium density fibreboard from the extracted and unextracted woodchips. The boards were produced with a 13 % urea resin, and a 3 % isocyanate resin to obtain three densities which were targetted at 650, 750, and 850 kg/m³. The same resin concentrations and types were used to produce board of the target density of 750 kg/m³. The properties of the boards from the extracted unextracted materials were determined and compared. and The chemical components of the wood were 64.27 % holocellulose, 35.63 % alhpa-cellulose, 34.38 % lignin and 1.5 % ash, with the pH of 5 to 5.1. The extracted woodchips yielded 88.35 % fibre whilst the unextracted woodchip yielded 77.92 % fibre. The strength properties of boards from the extracted woodchip with 13 % urea resin met the 300-type of JISA 5906 for all three densities . The boards with 3 % isocyanate resin met the 150-type for 650 kg/m3 and 750 kg/m3 and met the 300-type for 850 kg/m³. The urea bonded boards gave higher strength than those bonded by isocyanate resin. The 750 kg/m³ boards from the unextracted woodchip gave higher MOR with the urea than the isocyanate resin