Fabric laminated composites with excellent mechanical strength and brake stability are now developed as promising wet friction materials. However, facing the serious challenge of persistent operation under harsh conditions, the resistance and interlaminar bonding properties of laminated composites urgently require further improvement. In this study, methylene diphenyl diisocyanate (MDI) was chemically grafted onto a carbon fiber powder (CFP) surface via an oil bath for surface functionalization. Fabric laminated composites modified with functionalized CFP (CFP-MDI) were subsequently fabricated by sedimentation to construct a “brick and mortar” structure. As a result, the comprehensive performance of laminated composites was effectively promoted by the introduction of CFP-MDI as a mortar. In particular, owing to the conspique synergistic effect between CFP and MDI, the interlaminar shear strength (ILSS) of the modified laminated composite increased by 17.93%, and the wear rate decreased by 38.18%, from 7.91×10⁻¹⁴ to 4.89×10⁻¹⁴ m³/(N·m), demonstrating the excellent ability of the modified composite to efficiently suppress crack and local damage propagation. This work provides a new strategy to achieve the integrated construction of toughening interlaminated and wear-resistant coatings, which is conducive to the large-scale application of laminated fabric composites in the friction transmission braking field.

Paper-based friction materials are porous materials that exhibit anisotropy; they exhibit random pore sizes and quantities during their preparation, thereby rendering the control of their pore structure difficult. Composites with different pore structures are obtained by introducing chemical foaming technology during their preparation to regulate their pore structure and investigate the effect of pore structure on the properties of paper-based friction materials. The results indicate that the skeleton density, total pore area, average pore diameter, and porosity of the materials increase after chemical foaming treatment, showing a more open pore structure. The addition of an organic chemical foaming agent improves the curing degree of the matrix significantly. Consequently, the thermal stability of the materials improves significantly, and the hardness and elastic modulus of the matrix increase by 73.7% and 49.4%, respectively. The dynamic friction coefficient increases and the wear rate is reduced considerably after optimizing the pore structure. The wear rate, in particular, decreases by 47.7% from 2.83 × 10⁻⁸ to 1.48 × 10⁻⁸ cm³/J as the foaming agent content increases. Most importantly, this study provides an effective method to regulate the pore structure of wet friction materials, which is conducive to achieving the desired tribological properties.