DefinePK

Abstract

ABSTRACT Rajkoroi (Albizia richardiana) wood has been studied for assessing it suitability for plywood and particleboard manufacture. It was found that 1.5 mm thick smooth and figured veneer can be peeled and dried easily. Three-ply plywood were made using veneer of this species bonded with liquid urea formaldehyde glue of 50% solid content extended with wheat flour and catalyzed with 2% hardener (ammonium chloride) under the three specific pressures, viz, 1.05 N/mm2, 1.40 N/mm2, 1.76 N/mm2 in three replications at 6 minute press time and 120oC press temperature. Dry and wet shear test were conducted on the plywood samples and their shear load at failure per unit area and percentage of wood failure were determined. 1.05 N/mm2 pressure for the manufacture of ply wood was found to be the best. Particle board was manufactured from the chips of obtained from wasted veneer pieces using 10% UF resin glue (solid content) on the oven dried weight of the chip. The particleboards were tested for determining the strength and dimensional stability. The tensile strength passed the British and German standard specification, bending strength was found nearest to Indian Standard but not met with German and British standard specification. Key words: Rajkoroi, particleboard, modulus of rupture, internal bond strength, urea formaldehyde, ammonium chloride, hardener.