Optimization of wetting properties based on polymer–inorganic–nonsolvent hybrid materials

Superhydrophobic coatings are an answer to surface wettability challenges because they keep surfaces dry, self-cleaning, and prevent corrosion, in several areas of industrial application that require coatings with these properties. In this research work, we describe a new formulation strategy to achieve a superhydrophobic polystyrene coating that includes the combined use of SiO₂ nanoparticles and a nonsolvent. The effect of SiO₂ nanoparticles (X1, % weight), substrate temperature (X2, °C), and substrate drying time (X3, min), on the apparent static contact angle (ASCA) and the surface roughness (SR), was investigated by using response surface methodology (RSM). The optimal point predicted through RSM was confirmed experimentally, and according to the experimental values of X1 (47.0% weight), X2 (163.0°C), and X3 (64.0 min), the maximum values of ASCA and SR were 172.0° and 64.8 nm, respectively, with a slip angle of 2°. The RSM analysis indicates that the combination of the concentration of SiO₂ nanoparticles and the nonsolvent leads to better superhydrophobic behavior. SEM micrographs showed that the SiO₂ nanoparticles were randomly dispersed on the surface of the substrate. This synthesis methodology can be applied to different types of moderately heat-resistant materials.