The Effect of Gambir Adhesive Level and Hot Press Temperature on Physical and Mechanical Properties of Bamboo Particleboard

Abstract

: Gambir is the extract of leaves sap and young twigs of gambir plants, which contains tannin.Gambir-formaldehyde adhesives have been applied to the particleboards, butsome properties of particleboard produced did not meetthe standard.In this study, gambir adhesives (without formaldehyde) were applied to the bamboo particleboard.The dimension of particleboard was 25x25x1 cm, and the board density target was set at 0.8 g/cm3. Three kinds of adhesive levels (10, 20, 30%) and four kinds of hot-press temperature (160, 180, 200, 220 o C) were used for particleboard production. The research aimed to investigatethe effect of gambir adhesive level and hot-press temperature on the physical and mechanical properties of the bambooparticleboard. The physical and mechanical properties of particleboards were then evaluated and compared to the JIS A5908-2003 standard.The study showed that adhesive level and hot-press temperature affected significantly on thickness swelling, water absorption, internal bond, modulus of rupture and modulus of elasticityof particleboard, while the effect of an adhesive level factor was also significant on density properties.Interaction between adhesive level and hot-press temperature factor only affected significantly on water absorption. Particleboards with hot-press temperatures of 200 o C and 220 o C have better properties than others.The high hot-press temperature has exceeded the melting point of the catechin (174-178 o C), furthermore, the gambir adhesive becomes hardened and cured. The most optimal bamboo particleboard is particleboard with 220 o C hot-press temperature and adhesive level of 30%, based on the best of particleboard properties compared to JIS A5908-2003.