Superhydrophobic coating composed of rosin acid and TiO2 with antimicrobial properties and excellent mechanical durability for oil/water separation

Developing multifunctional materials with green, lasting, and simple preparation processes is a hot topic and challenge in solving the problem of oil spill contamination. A multifunctionalized superhydrophobic coating was generated via cross-linking 3-(Trimethoxysilyl) propyl acrylate with Polyethyleneimine in a multifunctional covalent manner and modifying the cotton fabric surface with silylated modified rosin acid (RA-Si) as well as TiO2 nanoparticles. The coated samples had remarkable superhydrophobicity with self-cleaning as well as stain resistance. With bactericidal rates of 97.73 % and 98.36 %, respectively, the coated samples effectively inhibited the formation of biofilms and showed high antimicrobial performance for both Staphylococcus aureus and Escherichia coli. Meanwhile, the coated samples showed outstanding oil absorption and separation of the oil-water mixture. Both water-in-oil and oil-in-water stable emulsions would be effectively separated out of the coated samples after demulsifying. Additionally, the water droplet contact angle of the coated samples was maintained at approximately 150.0° after mechanical and chemical testing. It was noteworthy that the coated samples still exhibited satisfactory separation for stabilizing oil/water emulsions after mechanical wear and chemical corrosion treatment, indicating their excellent mechanical durability. The prepared multifunctional RA-TiO2 superhydrophobic coating has promising applications in oil-containing wastewater treatment and environmental remediation.