Experimental investigation on physical and mechanical properties of a recycled polymer composite material as a function of the filler size

Knowing the basic properties of a new material is paramount when using it but also allows to infer its performances and subsequently to improve them. This work set out to determine the physical and mechanical properties of a wood plastic composite (WPoC) based on dissolved polystyrene in petrol and mixed with teak sawdust. The evolution of the density, porosity, absorption, thickness swelling, Young modulus, maximum stress and Poisson's ratio, of this WPoC are studied as a function of its composition. The obtained results show that it has a low water absorption rate and a negligible rate of thickness swelling, which makes it likely favorable for use in contact with water. Its porosity depends on the size of the wood particles that make it up. From a mechanical point of view, the WPoC presented in this paper shows a short plastic domain in tension and a ductile-type behavior in compression. On overall, its mechanical characteristics decrease as the size of the wood particles increases due to insufficient adhesion of the wood-matrix interface, the residual presence of solvent being the main responsible of it. The mechanical properties of the WPoC could be improved if consideration is given to removing the solvent from it, with the possible use of a coupling agent and plant fibers such as hemp fibers