Structural, thermal and mechanical analyses of banana midrib fiber reinforced polypropylene composite of improved properties

Natural fiber has attracted considerable interests as reinforcing agents in polymer composites for the transportation industry because of their low cost, lightweight, strong mechanical performance, and eco-friendly advantages. This study investigates the banana midrib fiber (BF) incorporated polypropylene (PP)-based composites using extrusion molding. The mechanical properties of the resulting biocomposites exhibited substantial improvements, with an increase in Young’s modulus by 79%, tensile strength by ~ 23%, and flexural modulus by 128% at a fiber content of 7 wt%. Additionally, the yield modulus and resilience of the composites increased by ~ 31% and 39% at the same fiber concentration. Thermal stability improved with a 10 °C increase in T_onset temperature compared to neat PP, indicating enhanced thermal stability. Fourier transform infrared spectroscopy confirms the chemical interactions between the fiber and PP matrix, while field emission scanning electron microscopy provided insights into fiber-matrix interfacial bonding through fractured and smooth surface analysis. These findings emphasize the important influence of fiber content on improving the mechanical and thermal properties of PP/BF composites. Furthermore, the results demonstrate the potential of BF-reinforced PP composites as lightweight, cost-efficient, and sustainable materials for use in automotive applications.