Robust, Multiresponsive, Superhydrophobic, and Oleophobic Nanocomposites via a Highly Efficient Multifluorination Strategy.

Abstract

Artificial superhydrophobic surfaces are garnering constant attention due to their wide applications. However, it is a great challenge for superhydrophobic materials to simultaneously achieve good oil repellency, mechanochemical robustness, adhesion, thermomechanical properties, and multiresponsive ability. Herein, we propose a highly efficient multifluorination strategy to prepare superhydrophobic nanocomposites with the above features, which can be used as monoliths or coatings on various substrates. In this strategy, long-chain perfluorinated epoxy (PFEP) provides outstanding water/oil repellency, tetrafluorophenyl-based epoxy (FEP) possesses good thermodynamic compatibility with PFEP and increases the mechanical performance of the matrix, and carbon nanotubes grafted with perfluorinated segments and flexible spacers (FCNTs) tailor the surface roughness as well as impart multiple functions and ensure good binding interfaces. Notedly, all of the applications of constrained long-chain perfluorinated compounds are achieved via thiol-ene click chemistry, following the ethos of atom economy. The resultant PFEP30/FCNTs40 exhibits superhydrophobicity and oleophobicity, thermal conductivity (1.33 W·m-1·K-1), electronic conductivity (232 S m-1), and electromagnetic interference shielding properties (∼30 dB at 8.2-12.4 GHz, 200 μm). Importantly, after different extreme physical/chemical tests, the PFEP30/FCNTs40 coating still shows outstanding water/oil repellency. In addition, the coating exhibits good photo/electrothermal conversion ability and shows the potential for sensor application. Moreover, the novel strategy provides an efficient guideline for large-scale preparation of robust, multiresponsive, superhydrophobic, and oleophobic materials.