Investigation and numerical simulation of impact resistance in aramid composites with interfaces reinforced by carboxymethylated cellulose nanofibers

Abstract The effectiveness of aramid fiber‐reinforced polymer (AFRP) composites depends on a strong adhesion at the interface connecting the fibers to the matrix, which is essential for attaining the desired high energy absorption and effective distribution of impact forces in these materials. Subpar interfacial conditions contribute to inefficient load transfer and create stress concentrations, potentially diminishing impact resistance performance and causing severe failure. Cellulose nanofibers (CNFs) exhibit considerable potential for reinforcing interfaces within polymeric composite systems that are fiber‐reinforced, owing to their substantial tensile strength and modulus, extensive specific surface area, and versatile properties. However, due to the stable chemical properties of aramid fibers, CNFs cannot truly serve the role of phase reinforcement, which limits their application to AFRPs. In this work, we have adsorbed carboxymethylated cellulose nanofibers (CNF‐Cs) onto aramid fibers via a straightforward and efficient dip‐coating approach, increasing the friction coefficient between the fibers and thereby improving the internal friction of the woven aramid fiber reinforcement. This approach yields the CNF‐C interface and enhances the energy absorption efficiency of the composites, while preserving the impact resistance properties of the aramid fibers. The CNF‐C treatment yielded a 9.4% increase in the impact load and 12.05% increase in the toughness. This method strengthens the fiber‐matrix interface without reducing the aramid fiber's impact resistance. It offers a quick and reliable way to enhance the impact resistance of AFRP composites. Highlights The CNF‐Cs was developed to enhance composite impact resistance. Numerical simulation effectively analyzed the effectiveness of CNF‐Cs. The impact load capacity of the composite materials increased by 9.4%. The maximum deflection improved by 12.05%.