Effect of Hollow Cellulose Fibers From Agro‐Industrial Waste on the Mechanical, Morphological, and Thermal Properties of Nylon‐6 Biocomposites

ABSTRACT Governmental requirements for the use of environmentally friendly polymers and manufacturing processes are essential. This research focuses on the development of Nylon‐6 biocomposites (BC) reinforced with hollow cellulose fibers (HCF) extracted from agro‐industrial waste. Neither HCF nor Nylon‐6 was chemically functionalized to improve interfacial adhesion. The BC‐HCF were processed and injection‐molded with 5%, 10%, and 15% by weight of HCF. At 15% HCF, the Young's modulus and flexural strength increased by 34.45% and 12.6%, respectively. The storage modulus (G') rose from 1640 MPa to 2170 MPa with increasing fiber content. All HCF concentrations exhibited good interfacial adhesion, uniform fiber distribution, and efficient stress transfer from the matrix to the fibers. Scanning electron microscopy revealed that Nylon‐6 molecules infiltrated the hollow cavities of HCF, enhancing interfacial bonding. Differential scanning calorimetry (DSC) showed a 7.23% increase in crystallinity at 15% HCF, favoring α‐type crystal formation, which was confirmed by higher XRD peak intensities. Thermal stability remained unaffected by HCF content, while water retention improved with increasing HCF. This study demonstrates that innovative filler morphologies can improve the mechanical performance of engineering biocomposites without chemical modification. Additionally, using HCF supports circular economy principles through reuse, recycling, and waste reduction.