Facile fabrication of superhydrophobic coatings on concrete substrate

Abstract

PurposeThe purpose of this study is to prepare a chemically stable superhydrophobic coating with remarkable mechanical properties and concrete protective properties.Design/methodology/approachOne synthetic step was adopted to prepare superhydrophobic coating. The process and product were analyzed and confirmed by fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), water contact angle (WCA), transmission electron microscopy (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The mechanical properties were confirmed by tensile test. The concrete protective properties were confirmed by solution immersion test and rapid chloride migration coefficient test.FindingsMSiO2 nanoparticles (NPs) were chosen to enhance the hydrophobicity of fluorosilicone coatings. With a 4:1 mass ratio of fluorosilicone resin and MSiO2 NPs, the coatings show superhydrophobicity with a WCA of 156° and a SA of 3.1°. In addition, the tensile mechanical property was improved, and the chloride ion diffusion coefficient was decreased significantly after the addition of MSiO2 NPs.Practical implicationsThis new fluorosilicone coating hybrid by MSiO2 NPs could be applied as a concrete protective layer with properties of self-cleaning, antifouling, etc.Originality/valueIntroduction of MSiO2 NPs hybrid to prepare fluorosilicone coating with superhydrophobicity on concrete surface has not been systematically studied previously.