Preparation of tetrafluoro-λ6-sulfanyl bridged-bonding perfluoroalkyl styrene and its emulsion copolymerization with acrylate monomers for cotton fabrics finishing

4-(Perfluorobutyl)styrene, 4-(Perfluorohexyl)styrene, 4-[Perfluorobutyl(tetrafluoro-lambda(6)-sulfanyl)]styrene (C4F9-SF4-styrene), and 4-[Perfluorohexyl(tetrafluoro-lambda(6)-sulfanyl)]styrene (C6F13-SF4-styrene) were prepared in two or three steps. The short-chain perfluoroalkyl groups are modified through the insertion of tetrafluoro-lambda(6)-sulfanyl linked groups (-SF4-). The prepared perfluoroalkyl styrene acts as functional monomers to react with butyl acrylate, methyl methacrylate, and hydroxyethyl methacrylate for emulsion copolymerization to obtain side-chain fluoropolymers. The long-chain fluoropolymer formed in contrast to the tetrafluorosulfanyl (-SF4-) modified ones. The emulsions were applied on cotton fabrics to give hydrophobicity. The result showed that the fabrics treated with tetrafluorosulfanyl-modified fluoropolymers were more hydrophobic, indicating that the introduction of -SF4- was beneficial to provide lower surface energy and obtain better water repellent performance. The water contact angles record the varying degrees of variation in polymer degradation under UV exposure. The result showed that, as the perfluoroalkyl is bonded by -SF4-, when comparing with the carbon-chain perfluoroalkyl polymer, the tetrafluorosulfanyl-modified fluoropolymer is more degradable during UV irradiation.

Automated summary

Short-chain perfluoroalkyl styrenes were modified through insertion of tetrafluoro-lambda(6)-sulfanyl linked groups (-SF4-), forming side-chain fluoropolymers in emulsion copolymerization. Cotton fabrics treated with tetrafluorosulfanyl-modified fluoropolymers showed increased hydrophobicity compared to unmodified ones.