Block copolymers hybrid latex coatings with environment-friendly short-chain perfluoroalkyl: From sequence structure to surface properties

Abstract

Block copolymers (BCs) of perfluorocarbons (PFCs) show a well-ordered phase separation morphology on the surface that is an ideal structure to fabricate low surface free energy (SFE) environment-friendly short-chained PFCs based coating materials. In this study, a series of block copolymers of 2-(perfluorobutyl) ethyl acrylate hybrid latex coating materials were synthesized via soap-free RAFT emulsion polymerization. The impact of copolymers sequence structure on the surface properties and surface micro-nano structure of hybrid latex films were investigated. The results revealed that the functional chain segments of short-chain perfluorinated were preferentially arranged in the outermost chain segments of the BCs, thereby leading to the stacking of trifluoromethyl (-CF3) groups on the hybrid latex film surfaces and the decrease of SFE. The SFE of BCs latex films were significantly reduced from 21.83 mN/m to 16.03 mN/m compared to that of the random copolymer. Additionally, the SFE of the hybrid latex film can be reduced to 15.32 mN/m under the action of the modified silica crosslinking. Ultimately, the hybrid latex films show excellent superhydrophobic and oleophobic properties on cotton fabrics with water and oil contact angles of 152.5° and 142.4°, respectively, reaching the level of commercial water and oil repellent finishing agents with six fluorocarbon atoms. This study of BCs hybrid latex coatings provides important insights into the mechanism of the sequence structure and surface properties of BCs and offers an environment-friendly superhydrophobic and oleophobic coating material.