Thermal Properties of Isocyanate as Particleboard’s Adhesive

Abstract

Abstract The objective of this study was to evaluate the thermal properties of isocyanate as particleboard adhesives. In this study, thermal properties of the isocyanate was investigated particularly its curing behavior either using water or wood with a temperature range from 25 to 500°C using thermal analyzer (Mettler Toledo). When isocyanate is used as the binder in particleboard system, the reactive –NCO group reacted with water (because wood is a hygroscopic material and contains free water and bound water) and also with the –OH group from wood. Sample of isocyanate was H3M purchased from PT. Polichemie Asia Pacific and wood particle was Eucalyptus sp. taken from PT. Toba Pulp Lestari. About 10 mg of the mixture either isocyanate with water or wood in various weight ratios were scanned at four different heating rates (2.5; 5; 10; and 20°C/min). Results of this study showed isocyanate cured either using water or moisture wood particle indicated by the Tp or peak temperature on the thermograms of differential scanning calorimetry (DSC). However when isocyanate reacted with wood particle, the Tp emerged more than two which indicated isocyanate also reacted with wood components. Furthermore, values of enthalpy seemed irregular probably due to different structures and compositions of wood particle. This influence, however, was masked by the moisture present in the wood (free and bound water), because water was much easier to react with isocyanate than were the –OH within the wood particle. It was suggested to calculate activation energy since the heating rates used up to four and to understand whether water, wood particle, or both affected the main reaction mechanism among isocyanate, water within the wood (free and bound water), or wood components.