Epoxy polymer composites reinforced using Caryota biofiber: fiber characterization, mechanical performance, and tribological behavior

Abstract In this study, the potential of a novel Caryota (CY) biofiber as a reinforcement for epoxy-based polymer composites was systematically evaluated. The fiber was characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy to investigate its surface morphology, elemental composition, crystallographic structure, and chemical functional groups. The characterization results revealed a rough surface morphology, high carbon content, a semi-crystalline cellulose-rich structure, and functional groups favourable for effective fiber–matrix adhesion. Based on these characteristics, epoxy composites reinforced with 0, 10, 15, 20, and 25 wt% Caryota fiber were fabricated and evaluated for their mechanical and tribological performance. The composite containing 20 wt% fiber exhibited the highest tensile strength of 20.8 MPa, whereas the 15 wt% composite achieved the maximum flexural strength of 74.3 MPa. Erosive wear behaviour was investigated according to ASTM G76 under different impingement angles and impact velocities. The fiber-reinforced composites exhibited superior erosion resistance compared with neat epoxy, with the erosion mechanism transitioning from semi-ductile to semi-brittle behaviour as the impact velocity increased. Overall, the results demonstrate that Caryota biofiber is a promising, sustainable, and cost-effective reinforcement for polymer composites intended for structural and tribological applications.