A facile one-step fabrication of robust superhydrophobic/superoleophilic cotton fabric using a crosslinkable POSS-containing fluorinated copolymer

A superhydrophobic/superoleophilic cotton fabric was fabricated by a facile one-step dip-coating method using a crosslinkable fluorinated copolymer material-Poly(methyl methacrylate-co-butyl acrylate-co-hydroxyethyl methacrylate-co-perfluoroalkylethyl methacrylate-co-stearyl methacrylate-co-methacrylisobutyl polyhedral oligomeric silsesquioxane) (P(MMA-BA-HEMA-FMA-SMA-MAPOSS)). The copolymer was synthesized using a conventional solution free radical polymerization. Cotton fabric was dip-coated in tetrahydrofuran (THF) solution of the copolymer and curing agent with -NCO groups. The coated cotton fabric has a water contact angle above 150° and oil contact angle of 0°, showing both superhydrophobicity and superoleophilicity. Furthermore, the cotton fabric could keep its superhydrophobic property even after ultrasonic treatment in ethanol or thermal treatment, as well as for acidic or alkaline liquids. The coated cotton fabrics were used to separate various oil-water mixtures with separation efficiency all above 96%. Additionally, the cotton fabrics still kept high separation efficiency above 98% after 50 separation times for n-hexane/water mixture. These suggest that the coated cotton fabric possesses robust superhydrophobic property and excellent oil-water separation performance, and can finely meet the urgent request in oil-water separation.