Soft yet powerful: Nano-coatings preserve transfer film integrity

Abstract

Conventional carbon fiber (CF) surface modification typically relies on harsh chemical oxidation or costly physical radiation, which is not only technically challenging but may also weaken the intrinsic bulk fiber properties. Contrarily, a chaperone solvent assisted assembly (CSAA) strategy was employed to construct a soft, organic nano-coating using SDS@2β-CD nanosheets (SCD) of approximately 50 nm thick on a CF surface without relying on higher fiber surface inherent activity. The modified CFs (CF-SCD) were combined with polytetrafluoroethylene (PTFE) fibers and embedded into EP resin to prepare the CF-reinforced self-lubricating composites (CFRLCs). The composites displayed notably enhanced tribological properties, as well as excellent interfacial interaction between the fibers and the matrix. This indicated that the soft nano-coating on the CFs effectively prevented the hard particles from scratching the lubricant film on moving surface. Consequently, the composites exhibited a low coefficient of friction (COF) (0.046) and wear rate (9.69 × 10^-8 mm³/(N m)). The strategy proposed in this study provided a novel, efficient, and eco-friendly modification approach for strengthening the integrated CFRLCs structural components, which showed significant promise for engineering applications.