A Sustainable Strategy for Enhancing Recycled CFRP via Electro‐Spun Low‐Melting Temperature Polyamide Nanofiber Interlayers

ABSTRACT The increasing demand for lightweight materials with high specific strength has led to rapid growth in the use of carbon fiber reinforced plastics (CFRPs), accompanied by a significant increase in CFRP waste. Despite extensive efforts to recover carbon fibers, the structural reuse of recycled CFRP remains limited due to fiber damage, shortening, and interfacial degradation, which result in reduced mechanical performance. In this study, an interfacial engineering strategy based on electro‐spun low‐melting‐point polyamide (PA) nanofiber veils was proposed to restore the mechanical performance of recycled CFRP composites. Virgin CFRP composites were fabricated using chopped carbon fibers and subjected to tensile testing. The fractured specimens were then recycled via pyrolysis at 1000°C under an argon atmosphere to recover carbon fibers. Electro‐spun PA nanofiber veils were introduced into the recycled fiber network, followed by epoxy impregnation. The incorporation of PA nanofiber veils significantly enhanced the mechanical properties of the recycled composites. The tensile strength increased from 70 to 106 MPa (≈51%), while the elastic modulus improved from 4.2 to 6.3 GPa (≈50%). The tensile strain also increased from 1.4% to 6.0%, indicating improved ductility. FT‐IR analysis confirmed epoxy ring‐opening reactions with PA amide groups, forming covalent bonding at the interface. Combined with the nanofibrous bridging effect, this mechanism improved interfacial adhesion, enhanced load transfer, and suppressed crack propagation. The proposed approach provides a practical strategy for restoring mechanical performance in recycled CFRP and advancing sustainable composite recycling technologies.