Influence of chemical treatments on mechanical behavior of banana fibre reinforced carbon-kevlar intraply hybrid composites

This study explores the mechanical performance of a hybrid composite integrating natural banana fibres with synthetic carbon -Kevlar intraply fibres in a sandwich configuration. The hybrid design leverages the sustainability, low density, and biodegradability of banana fibres alongside the high strength and impact resistance of carbon and Kevlar. To enhance fibre–matrix bonding, Banana fibres were subjected to 5% NaOH and 0.5% KMnO₄ treatments to enhance fibre surface characteristics and interfacial bonding. Laminates were fabricated by sandwiching treated banana fibre layers between carbon-Kevlar intraply layers using hand lay-up and compression molding. Mechanical performance was evaluated through tensile, flexural, and Charpy impact tests. Results show that both chemical treatments improved mechanical properties compared to untreated composites, with KMnO₄ treatment yielding the highest tensile strength (87.98 MPa), flexural strength (104.12 MPa), and impact strength (34.19 kJ m⁻²). Scanning Electron Microscopy (SEM) revealed improved fibre-matrix adhesion and altered fracture morphologies corresponding to treatment types. These hybrid composites hold significant potential for sustainable high-performance applications in aerospace, automotive, and structural industries, where lightweight and impact-resistant materials are essential. This study advances sustainable materials from agricultural waste, contributing to SDG 9 (Industry, Innovation, Infrastructure), SDG 12 (Responsible Consumption and Production), and SDG 13 (Climate Action).