SiC-enhanced polyurethane composite coatings with excellent anti-fouling, mechanical, thermal, chemical properties on various substrates

Polyurethane (PU) coatings with excellent corrosion resistance and wear resistance are regularly used in furniture coating, metal corrosion protection, electronic device protection and other fields. However, due to the shortcomings of low hydrophobicity and thermal stability, PU coatings are limited to be widely used as waterproof and breathable materials. This is expected to be improved by nanoparticles with high thermal conductivity and robust properties, such as silicon carbide (SiC). Here, the SiC-enhanced PU composite coatings modified by perfluorooctyltriethoxysilane (PFOTS) were successfully fabricated by spraying. The dispersion of SiC after chemical grafting modification of PFOTS in PU was significantly improved. The hard SiC particles provided a special micro-nano structure on the surface of the PU coating, altering the wettability of the coating from hydrophilic to superhydrophobic. The 125 wt% F-SiC/PU composite coating showed the best superhydrophobic properties with good wear resistance, anti-stripping ability, thermal stability, salt spray resistance and acid/base resistance, which depends on the uniform dispersion of SiC with high hardness and high thermal conductivity in the PU coating. The 125 wt% F-SiC/PU composite coating can present superhydrophobic properties on different substrates, such as aluminum alloy, ceramic, plastic sheet and filter paper, and have certain anti-fouling properties. This research provides a new strategy for the development of wear-resistant and anti-fouling PU superhydrophobic coatings.