Thermal and Mechanical Enhancement of Sisal and Banana Hybrid Fibers Through Zno Nanoparticle Integration

This study explores the enhancement of mechanical and thermal properties in sisal and banana hybrid fiber composites by incorporating <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{Z n O}$</tex> nanoparticles. Composites were fabricated with varying ZnO weight percentages <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(0 \%, 1 \%, 2 \%, 3 \%$</tex>, and 4%) and subjected to evaluations to determine the optimal nanoparticle content for performance enhancement. Mechanical tests showed that tensile and impact strengths increased with the addition of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{Z n O}$</tex> nanoparticles, peaking at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{3 \%} \text{ZnO}$</tex>. The tensile strength reached a maximum of 55 MPa, and the impact strength peaked at 27 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{kJ} / \mathbf{m}^{2}$</tex>, indicating optimal reinforcement and fiber-matrix bonding at this concentration. Thermal conductivity also improved with ZnO up to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{3 \%}$</tex>, reaching a maximum of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{0. 3 2}$</tex> <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{W} / \mathbf{m} \cdot \mathrm{K}$</tex>. However, an excessive ZnO content (4%) led to nanoparticle agglomeration, slightly reducing both tensile and impact strengths and decreasing thermal conductivity. Scanning Electron Microscopy (SEM) analysis confirmed improved fiber-matrix interfaces and nanoparticle dispersion up to 3%, with agglomeration observed at higher concentrations. The study concludes that ZnO nanoparticles significantly enhance the mechanical and thermal properties of sisal and banana hybrid fiber composites, with 3% being the optimal concentration for achieving the best balance of reinforcement and dispersion. These findings provide valuable insights for the development of advanced natural fiber composites reinforced with nanoparticles.