Comparison of two micromechanical models for predicting elasto-plastic response of wood-plastic composites

The mechanical response of wood- and cellulose-filled polymers and its comparison to analytical models is studied in this article. To model the elasto-plastic response of the wood-plastic composite (WPC), two explicit semi-analytical micromechanical methods were used: Mori-Tanaka Method (MTM) and Generalised Method of Cells (GMC). For experimental purpose, several test specimens composed of matrix polypropylene (PP) or polystyrene (PS) and filled with wood or cellulose short fibres of different length to width aspect ratio and various volume fractions were injection moulded. Tensile testing was then used to gain experimental data, which were then compared to the calculated prediction of proposed micromechanical models to test their applicability. The comparison of results show that both methods can accurately predict the response of the composite in the elastic area; however Mori-Tanaka Method can achieve better results when forecasting plastic deformations of wood-plastic composites.