Characterization of Moringa oleifera husk biocarbon and bagasse micro fibre toughened vinyl-based microwave shielding composite for E-Vehicle

Abstract

This study presents the development of a vinyl ester-based composite reinforced with bagasse microfibers and biocarbon derived from Moringa oleifera husks, aimed at enhancing mechanical properties, dielectric permittivity, and EMI (Electromagnetic Interference) shielding effectiveness for potential applications in electric vehicle systems. First the biomass extracted biocarbon was prepared by under slow pyrolysis technique. The composite fabrication was carried out using a hand layup method with careful mixing of biocarbon from Moringa oleifera husks and uniform dispersion of bagasse microfibers, ensuring enhanced composite performance.Further, to evaluate their performance, as per ASTM standard the composite specimen is cut under abrasive water jet machine. Based on the result obtained, the composite specimen, VB2, with 2 vol.% biocarbon and 40 vol.% bagasse microfibre, exhibited superior tensile strength (135 MPa), flexural strength (155 MPa), and hardness (83 Shore-D), due to optimal filler-matrix interaction and effective stress transfer. Dielectric permittivity was also highest for VB2, reaching 6.1 at 8 GHz, and maintaining higher values across other frequencies, indicating strong interfacial polarization. For EMI shielding, VB2 achieved the highest total shielding effectiveness of 31.5 dB at 8 GHz and 68.25 dB at 18 GHz, driven by the combined effects of enhanced absorption and reflection through synergistic filler effects. SEM analysis confirmed that VB2 had a uniform dispersion of fillers, minimizing voids and agglomerations, which is crucial for maximizing mechanical strength and electromagnetic shielding. The sustainable use of natural fibers and biocarbon also highlights the environmental benefits of this composite for automotive applications, such as battery temperature control and wireless charging in E-vehicles.