Carbon nanotubes and carbon fiber filled polyhexahydrotriazine composites: Assessing the tribological and mechanical properties

Abstract Growing carbon nanotubes (CNT) on the carbon fiber (CF) surface resolves the issue of insufficient strong interfacial bonding between CF and depolymerizable poly(hexahydrotriazine) (PHT). The unique one‐dimensional structure of CNT is embedded as interlaminar reinforcement in PHT to create an effective mechanical interlock with the PHT matrix. This method significantly enhances the toughness and tensile strength of the composites, reaching 208.7 MPa. Tribological tests show that CNT with high specific surface area and typical graphitic structures enhance the tribological performance of composites. Compared to PHT/CF composites, PHT/CNT@CF composites were given an average friction coefficient that decreased to 0.15. Therefore, the CNT was cultivated to prepare high‐performance PHT/CNT@CF composites, which constituting an efficient approach and holding significant potential for applications within the realm of tribology. Highlights Uniform carbon nanotubes (CNT) on carbon fiber (CF) can improve interfacial bonding with poly(hexahydrotriazine) (PHT). PHT/CNT@CF composites showed excellent mechanical and tribological properties. Growth of carbon nanotubes offers an ideal route to high‐performance composites.