Preparation and characterization of superhydrophobic and highly oleophobic FEVE-SiO2 nanocomposite coatings

Abstract

Here, an excellent superhydrophobic and highly oleophobic nanocomposite coating composed of fluoroethylene-vinyl ether (FEVE) resin as a matrix for modified SiO2 nanoparticles was synthesized on a stainless-steel wire mesh substrate via a facile sol-gel method. The surface morphology, microstructure, composition, and roughness of the coatings were investigated by field emission scanning electron microscopy (FESEM) equipped with energy-dispersive spectroscopy (EDS) and atomic force microscopy (AFM). The most efficient coating with superhydrophobicity and high oleophobicity feature indicates the water and oil repellency with contact angles (CAs) of 152° and 141°, respectively, with the high adhesion to the substrate. The mechanism of amphiphobic behavior of the coating is mainly attributed to the micro-nano hierarchical structure of the coating owing to the increased roughness caused by the presence of SiO2 nanoparticles and their effective embedding into FEVE resin cross-linking with isocyanate and using metallic mesh substrate besides the reduced surface tension due to the using fluoroalkylsilanes (FASs), strong bonding of the film to the substrate via electrostatic and chemical interactions. Moreover, the coating preserves the promising long-term amphiphobicity after 10 days of immersion in water with the water and oil contact angles of 145° and 134°, respectively.