Physical, chemical and surface properties of wheat husk, rye husk and soft wood and their polypropylene composites

The main objective of this research was to study the potential of grain by-products such as wheat husk, rye husk as reinforcements for thermoplastics as an alternative or together with wood fibres. Thermal degradation characteristics, bulk density, water absorption and solubility index were also investigated. The particle morphology and particle size was investigated by scanning electron microscopy. Water absorption properties of the fibres were studied to evaluate the viability of these fibres as reinforcements. The chemical composition of fibre such as cellulose, hemicellulose, lignin, starch, protein and fat were also measured. Surface chemistry and functionality of grain by-products was studied by EDX and FT-IR. Polypropylene composites were fabricated using a high speed mixer followed by injection moulding with 40 wt.% of fibre load. Tensile and Charpy impact strength of resulting composites were investigated.