2020 年 69 巻 6 号 p. 434-439
As an effective utilization method of the oil palm trunks, particleboards were prepared using vascular bundles of the trunks. The vascular bundles were obtained by separating parenchyma from a trunk veneer using a hammer mill. The boards with density of 0.6 g/cm3, 0.7 g/cm3 and 0.8 g/cm3 and with resin content of 5%, 10% and 15% were prepared and comparatively evaluated. Isocyanate was used as an adhesive. Modulus of rupture, modulus of elasticity and thickness swelling of the specimens taken out from each board were measured according to JIS A 5908. Following results were obtained. 1) More than 90% of the particles were 20 mm to 50 mm in length. The particles of 20 mm to 30 mm accounted for 35% of the total. Some particles contained parenchyma, attached to the surface of a vascular bundle, but most of particles were vascular bundles only. 2)MOR of specimens obtained from a board with resin content of 10% or more sufficiently satisfied JIS A 5908. MOR and MOE of a board with resin content of 10% or 15% increased with increasing resin contents and densities on boards. The fracture strains were not changed with the resin contents and densities. MOR and MOE of the specimens obtained from boards with all conditions were higher than those prepared from purely oil palm trunk. 3)Thickness swelling of the specimens obtained from a board with resin content of 10% or more sufficiently satisfied JIS A 5908. Thicknesses swelling of the specimens obtained from board with all conditions were lower than coefficient of swelling of those prepared from purely oil palm trunk in the radial direction.