Superhydrophobic coatings based on raspberry-like nanoparticles and their applications on cotton

Abstract Superhydrophobic CH3-SiO2 and i-Bu-SiO2 copolymer coatings containing raspberry-like micro–nanoparticles were fabricated by emulsifier-free polymerization and sol–gel methods. The morphology of the particles could be controlled by simply adjusting the reactant ratio in the initial solution. The fluoride-free CH3-SiO2 copolymer and i-Bu-SiO2 copolymer composite coatings exhibited superhydrophobicity with water contact angles (WCAs) of 151.22° and 154.85° and sliding angles (SAs) of 5.03° and 4.85°, respectively. The coatings were applied on cotton to form superhydrophobic cottons resistant to water, milk, and coffee stains. The whole procedure was carried out under a mild environment, without toxic chemicals, costly instruments, or complex production processes. These advantages could provide a large-area preparation and marketability of the coatings.