Designing superhydrophobic surface based on fluoropolymer-silica nanocomposite via RAFT-mediated polymerization-induced self-assembly

Superhydrophobic surfaces (SHS) find versatile applications as coatings due to their very high water-repellency, self-cleaning, and anti-icing properties. This investigation describes the preparation of a SHS from surfactant-free hybrid fluoropolymer latex. In this case, reversible addition-fragmentation chain transfer (RAFT) polymerization was adopted to prepare a copolymer of 4-vinyl pyridine (4VP) and vinyl triethoxysilane (VTES), where the pyridine units were quaternized to make the copolymer soluble in water. The copolymer was further used as a macro-RAFT agent to polymerize 2,2,2-trifluoroethyl methacrylate (TFEMA) in a surfactant-free emulsion via polymerization-induced self-assembly (PISA). The macro-RAFT agent contained a small amount of VTES as co-monomer which was utilized to graft silica nanoparticles (SNPs) onto the P(TFEMA) spheres. The film prepared using the nanocomposite latex exhibited a nano-structured surface as observed by SEM and AFM analyses. Surface modification of the film with fluorinated trichlorosilane produced an SHS with a water contact angle (WCA) of 151.5 degrees. (c) 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 266-275