Modelling of vertical density profile of particleboard,manufactured from hardwood sawmill residue

Abstract

Particleboards are generally made in three layers using softwood as the major raw material. Limitation on natural wood resources and concerns about the carbon footprint of products has created a significant interest in environmentally friendly or ‘green’ building materials. Hardwood sawmill residue, which has been disposed as solid waste, was investigated by authors as the main raw material for producing particleboard at RMIT University, Australia. Physical and mechanical properties of final particleboard were measured and analysed against original materials and process variables. The density of a particleboard along its thickness direction is not uniform, and is called the vertical density profile (VDP) which is dependent upon processing parameters. The VDP influences particleboard properties including flexural strength and its dimensional stability and fastening capacity. It is important to influence the formation of the VDP, altering processing variables, to achieve optimum particleboard properties. This paper presents an attempt to develop a model to predict the formation of the VDP of hardwood residue particleboard compared to processing parameters, using the theory of experimental design. The advantages of such a model in optimising particleboard properties are also discussed.