EVALUATIONS OF STRUCTURAL, PHYSICAL, AND MECHANICAL PERFORMANCE OF POTASSIUM PERMANGANATE-TREATED POWDERED CORN COB-REINFORCED WASTE-POLYSTYRENE FOAM COMPOSITES

Abstract

This study investigates the structural, physical, and mechanical properties of potassium permanganate-Treated Powdered Corn Cob (TPCC) as a reinforcement for waste-polystyrene foam composites. Composites were prepared with varying filler contents (10–50 wt.%) and evaluated for density, water absorption, hardness, tensile strength, and flexural properties. The results showed a progressive increase in composite density with higher filler content, ranging from 1.042 g/cm³ (control) to 1.592 g/cm³ at 50 wt.%. Water absorption was minimal at lower filler levels, such as 2.015% at 20 wt.%, but increased significantly at higher contents due to the hydrophilic and agglomerative nature of corn cob particles. Hardness peaked at 345.7 at 40 wt.% filler due to enhanced interfacial bonding but declined at higher levels because of void formation. Tensile and flexural properties exhibited non-linear trends, with initial reductions at low filler levels but recovery and stabilization at moderate contents (30–50 wt.%). Flexural strength decreased from 23.625 MPa (control) to 11.016 MPa at 20 wt.%, then stabilized at approximately 18 MPa at 40–50 wt.%. Flexural modulus peaked at 2149.555 MPa at 40 wt.%, emphasizing the reinforcing effect of TPCC. These findings demonstrate the potential of TPCC as a sustainable reinforcement material, providing an optimal balance of structural and mechanical properties for eco-friendly composite applications.