Polypropylene/silica/rice husk ash hybrid composites: A study on the mechanical, water absorption and morphological properties

Polypropylene hybrid composites were made using silica and white rice husk ash (WRHA) fillers as reinforcing agents in the polypropylene (PP) matrix. Both fillers were used at the similar total filler loading i.e., 40% by weight of PP matrix. Results indicate that the increasing loading of WRHA in silica/WRHA weight ratio has increased the flexural modulus and tensile modulus but decrease the tensile strength, stress at yield, elongation at break, E-b and water absorption of PP/silica/WRHA hybrid composites. Degradation study shows that percentage loss of above properties increases with increasing the loading of WRHA in silica/WRHA weight ratio of composites. Scanning electron microscopy (SEM) of tensile fracture surfaces of composites indicates that silica has better adhesion with PIP matrix compared to WRHA.