The effect of different layered materials on the tribological properties of PTFE composites

Two-dimensional (2D) lamellar materials have unique molecular structures and mechanical properties, among which molybdenum disulfide (MoS2) and graphitic carbon nitride (g-C3N4) with different interaction forces served as reinforcing phase for polytetrafluoroethylene (PTFE) composites in the present study. Thermal stability, tribological and thermomechanical properties of composites were comprehensively investigated. It was demonstrated that g-C3N4 improved elastic deformation resistance and thermal degradation characteristics. The addition of g-C3N4 significantly enhanced anti-wear performance under different loads and speeds. The results indicated that PTFE composites reinforced by g-C3N4 were provided with better properties because the bonding strength of g-C3N4 derived from hydrogen bonds (H-bonds) was stronger than that of MoS2 with van der Waals force. Consequently, g-C3N4 exhibited better thermomechanical and tribological properties. The result of this work is expected to provide a new kind of functional filler for enhancing the tribological properties of polymer composites.