Preparation of a wear-resistant, superhydrophobic SiO2/silicone-modified polyurethane composite coating through a two-step spraying method

•A novel kind of superhydrophobic coating was successfully fabricated with a simple two-step spray method.•A silica/silicone-modified polyurethane (SiO2/SiPU) composite superhydrophobic coating was prepared.•The coating exhibits excellent robustness under mechanical abrasion.•The coating has self-cleaning in air and corrosion resistance performance. The preparation of superhydrophobic coatings has been extensively researched, but their practical applications are limited by complicated preparation processes and poor mechanical durability. This study proposed a simple, low-cost method of preparing superhydrophobic coatings. A nano-silica dispersion was sprayed onto a semi-cured silicone-modified polyurethane resin through a two-step spraying method. Subsequently, these materials solidified together to successfully prepare a superhydrophobic coating with 159° contact angle and 2° sliding angle. The prepared silica/silicone-modified polyurethane (SiO2/SiPU) superhydrophobic coating showed superhydrophobic property after being cyclically rubbed for 30 cycles on 1000-mesh sandpaper under a load of 200 g. The coating further exhibited good corrosion resistance when placed in strong acid and alkali environments and excellent self-cleaning properties in air. This simple and environmentally friendly approach may have enormous application potential in many fields.