Comparison between HB and HDF made from waste leather

Due to the ever-increasing scarcity of resources and raw materials in the wood panels industry, it is imperative to look for suitable alternatives to the established resources. Therefore a combination of the traditionally used and newly explored sources may reveal highly innovative ways. The goal of this study is to provide an insight into the behaviour a wood-leather-composite material and its possible new applications. Wet White (WW) and Wet Blue (WB) leather particles were used for this analysis and mixed with the wood fibres of spruce and beech. Wood - leather panels' combinations with 0%, 15%, 25%, 35%, and 50% leather amount were produced in two different production processes (wet and dry discontinuous process). To evaluate how the differences of the two production processes influence the mechanical properties of the panels, investigations concerning the internal bond (IB), bending strength (MOR) and modulus of elasticity (MOE) were conducted. The leather content of the panels and the production process affected the results of the material properties. In the case of urea-formaldehyde (UF) bonded high-density fibreboards (4,5 mm, 900 kg/m3) the results show a non-linear improvement of the IBs with increasing leather content, whereas MOE and MOR decrease. The hardboards, (3,5 mm, 900 kg/m3) which were produced in the wet process with 1% phenol formaldehyde resin, show a similar behaviour in MOE and MOR to the HDF panels, but differ in tensile strength. The results give an overview how the leather amount infuences the board properties of two different panel types. Furthermore the here published results enable a convincing comparison between the mechanical properties of the two wood-leather composite board types. © Forest Products Society 2015.