Polymeric ionic liquids for the fast preparation of superhydrophobic coatings by the simultaneous spraying of oppositely charged polyelectrolytes and nanoparticles

In this work, the fabrication of superhydrophobic coatings by the simultaneous spraying of oppositely charged polyelectrolytes and nanoparticles is reported. This method is based on the polyelectrolyte layer-by-layer method but utilizes a fast simultaneous spraying approach. Superhydrophobic coatings showing water contact angles >150 degrees were obtained using poly[(1-vinyl-3-ethyl imidazolium) bis(trifluoromethane sulfonyl) imide] as a fluorinated polyelectrolyte alternative to Nafion. To obtain superhydrophobic thin films, fumed silica nanoparticles and clay nanorods were introduced into the polyelectrolyte multilayer films. The resultant superhydrophobic films showed both micro-and nano-scale features, as revealed by scanning electron microscopy and atomic force microscopy. Our polymeric ionic liquid derivatives show synthetic advantages compared with classic fluorinated polyelectrolytes. Polymer Journal (2011) 43, 966-970; doi:10.1038/pj.2011.104; published online 26 October 2011