Hybrid biocomposites from agricultural residues: mechanical, water absorption and tribological behaviors

Abstract

Abstract As south India is abundant with agricultural residues such as coir pith, rice husk and groundnut shell, this investigation is focused on using these residues as particle reinforcement for epoxy composites. The properties of coir pith, rice husk and groundnut shell particles were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Moreover, particle sizes of residues were confirmed with a particle size analyzer. The particles were hybridized with different combinations and reinforced in epoxy matrix by means of the compression molding technique. The weight fraction of hybrid particles in the composites was varied in different proportions (7.5 wt%, 15 wt%, 22.5 wt% and 30 wt%) and their effects on mechanical, wear and water absorption properties were studied. The fracture mechanisms of the composites were studied using scanning electron microscopy (SEM). The result showed that the addition of rice husk with coir pith and groundnut particles improved the mechanical and water retention properties of the composites, whereas addition of groundnut particles with coir pith improved the wear behavior of the composites.