Surface Properties, Wear Resistance, and Corrosion Resistance of TelechelicPerfluoropolyethersSelf-assembled Films

In recent years, with the continuous acceleration of industrialization and urbanization, various equipment surfaces are frequently exposed to harsh environments and pollution sources, leading to an increasing demand for antifouling and corrosion resistance of material surfaces. As the complexity of demands and environments grows, traditional protective coating materials gradually prove inadequate. Therefore, it was highly significant to develop multifunctional composite coatings that possessed anti-fouling, wear-resistant, and corrosion-resistant properties. Polysiloxane and its modified materials primarily consist of silicone polymers or silicone-modified polymers as film material coatings. These materials exhibited exceptional thermal stability, weather resistance, chemical corrosion resistance, hydrophobicity, low surface energy, and excellent biocompatibility due to their unique valence bond structure. However, this structure also affected their wear resistance and oleophobic properties. Consequently, introducing both wear-resistant groups and amphiphobicity into organosilanes becomes necessary. In order to further enhance the antifouling capabilities as well as the wear- and corrosion-resistance of coating materials, In this study, amphiphilic Z-type telechelicperfluoropolyethers with double-terminated siloxanyl groups (PFSi, Mn≈10 000) were synthesized through a substitution reaction using potassium borohydride and trimethoxy-chlorosilane. The silicon and copper sheets were hydroxylated after cleaned and UV-Ozone treated, allowing for the growth of PFSi on their surfaces to form self-assembled films. The surface properties and wear resistance of the self-assembled film were investigated, along with the corrosion resistance of the remote claw type perfluoropolyether film. Results demonstrated that compared to pure silicon wafers, the PFSi self-assembled film significantly improved water repellency, diiodomethane repellency, seawater repellency, ethanol repellency and nonane repellency. Surface tension measurements using Owens two-liquid method revealed that the surface tension of PFSi self-assembled films at different concentrations was less than 10 mN/m. Scanning electron microscopy analysis showed that the self-assembled film on silicon wafer surfaces had a multi-layer structure with thickness increasing as concentration increases. Furthermore, accelerated wear tests indicated excellent wear resistance of the PFSi self-assembled film, which improved with higher concentration levels. Electrochemical corrosion tests also demonstrated effective prevention of corrosion factors on copper substrates by the PFSi self-assembled film thereby enhancing metal surface corrosion resistance. This study investigated the behavior of amphiphilic telechelicpolymers in solid surface self-assembly to develop low surface energy films with abrasion and corrosion resistance capabilities, thus providing a new approach for designing fluoropolymers with controllable self-assembly functions.