Mechanical/thermomechanical properties of cotton-polypropylene composites developed via homogeneously blended preform

This research investigates cotton-polypropylene (PP) biocomposites developed by heat pressing homogeneous blends of cotton and PP fibers to enhance mechanical performance. Unlike conventional stacking or melt-mixing approaches, a homogeneously blended fiber preform technique was applied in this study to improve fiber dispersion and interfacial bonding in the composite without the use of compatibilizers or surface treatments. Different volume fractions of cotton and PP fibers were used to fabricate composites, and the mechanical and thermo-mechanical characteristics of the developed cotton-PP composites were evaluated. The composite with 40% cotton fiber showed the highest tensile and flexural strength of 64.46 MPa and 138.90 MPa, respectively. The developed materials, due to good fiber miscibility, exhibited substantial improvements in tensile (70–80%), flexural (110–130%), and impact (120–140%) strength compared to cotton-PP composites fabricated using different techniques, as reported in previous studies. The dynamic mechanical analysis revealed that 40% cotton fiber composite has the highest storage modulus of 4245.9 MPa and the lowest loss modulus of 180.55 MPa for the 30% cotton composite. The Cole-Cole plot confirmed the homogeneity of the composite due to uniform blending of cotton fiber and the PP matrix. The findings provide a promising pathway for fabricating high-performance cotton-PP composites using the uniform blending techniques, and the material’s mechanical and thermo-mechanical characteristics demonstrate the potential of utilizing cotton fiber-reinforced composites for diverse engineering applications.