Multifunctional Durable Superhydrophobic Coating Construct by Rosin Acid with Oil–Water Separation and Antimicrobial Property

Rosin acid has a broad range of applications in the industrial sector and significant economic value with applications in biomedical materials, fluorescent materials, and coating materials. However, developing rosin acid–based materials with high performance and added value remains a hot topic and challenge. This work introduces the preparation of a rosin acid–based polymer (poly(DR-AS)) by combining a double-bond modified rosin acid monomer with allyl triethoxysilane (AS) through reversible addition–fragmentation chain transfer (RAFT) polymerization. Concurrently, a poly(DR-AS)@TiO2 coating was constructed on cotton fabric using poly(DR-AS) and nanometer-sized titanium dioxide (TiO2). The poly(DR-AS)@TiO2 coating possessed simultaneously an excellent water droplet contact angle (165°) and water sliding angle (<9°), and it exhibited favorable self-cleaning ability and liquid repellency properties to common liquids. Meanwhile, the coated samples displayed outstanding oil–water separation capabilities with excellent permeation flux (7600 L·m–2·h–1) and high separation efficiency (99.3%). Besides, the emulsions (oil-in-water or water-in-oil) could be effectively separated by the coated samples. Additionally, after mechanical and chemical treatments, the water droplet contact angle of the coated samples still reached 150°. Ultimately, the coated samples also exhibited high antimicrobial property for Escherichia coli (antimicrobial rates = 98.57%) and Staphylococcus aureus (antimicrobial rates = 99.51%). These excellent performances promote poly(DR-AS)@TiO2 coating application in the oil–water separation field and antibacterial treatments.