Physical Properties of Medium-density Particleboard Made from Saline Eucalyptus

Abstract

Eucalyptus tree, Eucalyptus cinerea, has the potential to be used as a biomass crop to help manage saline subsurface drainage water in arid land where irrigated agriculture is practiced. In this research, saline eucalyptus was used to manufacture medium-density particleboard in an attempt to develop value-added application for the saline wood. This study investigated the effects of wood species (non-saline and saline), particle size, adhesive, bark content (BC), resin content (RC), and hot water treatment on the mechanical and water resistance properties of the medium-density particleboards made with eucalyptus woods. The measured mechanical properties included tensile strength (TS), modulus of rupture (MOR), modulus of elasticity (MOE) and internal bond strength (IB) of the finished particleboards. The water absorption and thickness swelling were tested to evaluate the water resistance properties. The particleboard made with 4% polymeric methane diphenyl diisocyanate (PMDI) resin had better qualities except for MOR than the particleboard made with 7% urea formaldehyde (UF). The particles of medium size (20 to 40 mesh) gave higher particleboard qualities, except for TS, than the smaller size (40 to 60 mesh) and larger size (10 to 20 mesh) particles. The qualities of particleboard were improved as the content of UF resin increased from 7% to 16%. The mechanical properties were deteriorated as BC increased from 0% to 15.4%, but the water resistance was improved. The particleboard made from hot water treated wood particles had better qualities compared with particleboard made from untreated particles. The particleboard made from saline wood had much better qualities than the particleboard made from non-saline wood. It has been concluded that saline eucalyptus is an appropriate material for manufacturing particleboards.