Single multifunctional MXene-coated glass fiber for interfacial strengthening, damage self-monitoring, and self-recovery in fiber-reinforced composites

The incorporation of interfacial functional materials for realizing interfacial damage self-monitoring and self-recovery with preserved interfacial properties of composites remains challenging. Herein, a single multifunctional MXene-coated glass fiber (GF_M) was prepared by a simple electrophoretic deposition (EPD) process. The as-fabricated functional glass fiber is embedded in the polymer matrix to demonstrate the capabilities in enhancing interfacial strength, monitoring and recovering the damage. The effects of the MXene coating on the fiber filaments’ mechanical properties and interfacial properties of fiber-reinforced polymeric composites are also investigated. The results showed the plate-like MXene coating obviously enhances the tensile strength of a single fiber by 8.1% due to bridging the surface defects by nanosheets. The interfacial shear strength of the as-obtained GF_M/resin composite is 22.4% higher than that of the pristine fiber/resin composite. Meanwhile, the interfacial evolution behavior is monitored during quasi-static tensile testing through measuring the resistance change of GF_M, and data revealed that GF_M is endowed with in-situ damage monitoring and failure warning. Additionally, the excellent electrical conductivity of MXene coating enabled GF_M to work as a heater for recovering the interfacial damage of thermoplastic composite. The self-recovery ability is demonstrated through the recovery of the mechanical-electrical response. Overall, the proposed GF_M looks promising for producing enhanced fiber-reinforced composites with great damage self-monitoring and self-recovery capability.