Non-equilibrium Plasma Treatment of Banana Fiber to Improve the Morphology and Mechanical Performance of Composites

Growing environmental and sustainability concerns have intensified the demand for lightweight eco-friendly materials. Natural fibers like banana fiber show poor compatibility with polymer matrices due to hydrophilic–hydrophobic mismatch. Although chemical treatments improve fiber–matrix bonding they are costly and environmentally intensive whereas plasma treatment provides a sustainable, cost-effective alternative without altering bulk properties. A non-equilibrium plasma modification using O2 gas was carried out for half an hour at power levels of 80 W and 120 W to enhance the mechanical properties, surface morphology and interfacial compatibility of banana fiber. Composites were fabricated by the hand-lay method using epoxy as the matrix incorporating treated and untreated banana fiber at 10–40 wt%. The non-equilibrium plasma O2 plasma treatment significantly improved the composite performance yielding enhancements of 79.19% in interlaminar shear strength, 62.87% in flexural strength, 37.24% in tensile strength and 150% in elongation compared to the untreated samples. These performance gains were largely attributed to improved interfacial bonding, increased surface roughness and the development of a stable surface coating. Nonequilibrium plasma O2 plasma-treated banana fiber at 80 W (half an hour) exhibited an average diameter of ~290 μm with rupture force, tensile strength, and deformation of 3.52 N, 53.31 MPa and 11.6% respectively. Fourier transform infrared spectroscopy and scanning electron microscope confirmed fiber oxidation and hydrophobic surface formation while X-ray diffraction showed enlarged crystallites, improved crystalline restructuring and reduced amorphous content (crystallinity index = 0.543, amorphicity index = 0.456, % CI = 54.37) validating enhanced fiber reactivity and the suitability of plasma-treated banana fiber for sustainable automotive, construction, and packaging applications.

Cite this article as: Gupta, U. S., Gupta, M., Tiwari, S., Sharma, U., & Chandrakar, A. (2026). Non-equilibrium plasma treatment of banana fiber to improve the morphology and mechanical performance of composites. Forestist, 76, 0052, doi: 10.5152/forestist.2026.25052.