Superhydrophobic and highly oleophobic coatings based on litchi-like FDA-SiO2-PS nanocomposite with excellent self-cleaning and anti-bioadhesion performances

The development of superhydrophobic and highly oleophobic nanocomposites that are highly adhesive to substrates is a major challenge in surface-related technologies. In this study, litchi-like polystyrene (PS) particles were prepared by soap-free emulsion polymerization with styrene (St) as monomer, KH-570 as crosslinking agent and KPS as initiator. Dual-sized litchi-like 1H,1H,2H,2H-perfluorodecyltriethoxy silane-SiO2-PS (PFDTES-SiO2-PS) particles was sol–gel synthesized using TEOS, PS, and PFDTES. Special superhydrophobic, highly oleophobic, and highly adhesive FDA-SiO2-PS (fluoride hdroxyl acrylate-resin-SiO2-PS copolymer) coatings were fabricated by embedding fluorosilane-modified litchi-like SiO2 particles in fluoride hdroxyl acrylate-resin (FHA resin) followed by curing through cross-linking using free radical polymerization. The structure, surface morphology, and properties of the coatings were examined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurements, and chemical analysis. The measured Ra roughness value was 181 nm for FDA-SiO2-PS coating. The fluorine-containing groups have a strong tendency to direct themselves to the coating surface, resulting in a superhydrophobic and highly oleophobic coating (water and CH2I2 contact angles of 169.61° and 137.04°, respectively, and a water rolling angle of 4.35°) that is also highly adhesive to substrates (adhesion 5B). Exposing to air for 24 months, the coating possessed long air-stability with contact angles of 159.31° and 135.04° for water and CH2I2, independently. Furthermore, the FDA-SiO2-PS coating endows it with excellent antifouling and self-cleaning abilities, and resistance to E. coli and platelet adhesion; hence, FDA-SiO2-PS is a promising coating for use in biomedical and marine antifouling applications.