Layer-by-layer macroassembly of inorganic CNTs and MXenes with organic PVA for enhancing the interfacial properties of carbon fiber/epoxy composites

In this study, two inorganic nanomaterials, MXenes and carbon nanotubes (CNTs), with different dimensions were directly used to modify carbon fiber (CF) fabrics using polyvinyl alcohol (PVA) as an organic binder through the layer-by-layer vacuum filtration method to improve the weak interface between the CF fabrics and epoxy (EP) resin matrix. These two-dimensional nanomaterials are observed to bond tightly to CF fabrics, and the wettability of CF fabrics is significantly improved owing to the organic-inorganic multistage interface structure. The surface energy of MXenes-CNTs-CF fabrics was 86% higher than that of pure CF fabrics. Correspondingly, the interlaminar shear strength (ILSS) of MXenes-CNTs-CF/EP composites was 30% higher than that of the pure CF/EP composites. Our study demonstrates a novel, simple, and effective method for modifying the interfacial properties between CFs and polymers using nanomaterials.