Epoxy-based hybrid composites reinforced with banyan fiber and banyan fruit powder for lightweight structural applications

Natural fiber–toughened polymer materials are attractive sustainable alternatives to synthetic composites, though their applications are often limited by insufficient mechanical strength and high moisture sensitivity. This study develops epoxy composites reinforced with banyan fiber (BF) and hybridized with banyan fruit powder (BFP) to enhance mechanical performance and durability. Composites containing 10–40% (by wt) BF were initially fabricated to determine the optimal fiber content, after which a fixed 30% (by wt) BF epoxy system was modified with 1–3% (by wt) BFP. Mechanical testing showed that the E30BF2BFP composite exhibited the best overall performance, achieving tensile and flexural strengths of 87 and 132 MPa, respectively, along with an impact strength of 6.9 kJ/m² and a hardness of 87 Shore D. Scanning electron microscopy confirmed improved fiber–matrix interfacial adhesion and uniform dispersion of BFP, enabling efficient stress transfer and reduced microstructural defects. Although the incorporation of natural reinforcements increased water absorption compared to neat epoxy, increasing BFP content progressively reduced moisture uptake, with a minimum value of 5.6% observed for the E30BF3BFP composite. This reduction is attributed to pore- filling and restricted capillary pathways within the matrix. Overall, the optimized BF–BFP hybrid composites combine lightweight characteristics with enhanced strength and moderated moisture sensitivity, making them suitable for semi-structural applications such as automotive interior panels, consumer product housings, and lightweight structural components. The study demonstrates the potential of locally abundant banyan-based resources for developing cost-effective, scalable, and sustainable composite materials.