Experimental Investigation of Mechanical, Thermal, and Physical Properties of Epoxy / Kevlar Composite with Bi-Filler (NiCo₂O₄ Nanoparticles and Wood Sawdust) Reinforcement

The advancement in the development of hybrid filler-reinforced composites widens its usability in structural applications as a replacement for conventional materials. Filler incorporation into the composites imparts out-of-the-ordinary enrichment to material properties and plays a significant role in enhancing its physical, mechanical, and thermal characteristics. In this work, NiCo₂O₄ nanoparticles are synthesized using a sol-gel method to ensure the homogeneity and purity of the nanoparticles. The obtained nanoparticles are characterized with XRD and the crystallite size is calculated using Scherrer’s formula, ranging between 16 and 22 nm, with spherical morphology observance using FESEM. This NiCo₂O₄ nanoparticle (synthetic filler – with varying wt% as 0.5, 1, 1.5, and 2 wt%) and wood sawdust (natural filler – with fixed wt% as 5 wt%) are the bi-fillers used to fabricate the Epoxy/Kevlar composites using open-mold hand layup technique. FTIR confirms the functional groups that correspond to Epoxy, Kevlar, and NiCo₂O₄ nanoparticles. Among filler-loaded composites, 1.5 wt% of NiCo₂O₄ nanoparticles/ 5 wt% wood sawdust reinforced Epoxy/Kevlar composites show a superior tensile strength of 61.9 MPa that signifies the strong filler-matrix bonding and less porosity. High thermal stability is observed for 1.5 wt% of NiCo₂O₄ nanoparticles/ 5 wt% wood sawdust reinforced Epoxy/Kevlar composites, wherein, an increase in weight loss of the filler-loaded composite implies better thermal conductivity of the matrix system for different filler loading. Physical properties seem to be better for 1 wt% of NiCo₂O₄ nanoparticles/ 5 wt% wood sawdust reinforced Epoxy/Kevlar composites that prevent the composite from microcracking due to low wettability. With continued research, this composite material has the potential to expand the application range of novel materials based on the epoxy matrix.