Preparation method of SiO2/polymer combined superhydrophobic coating

The invention discloses a preparation method of a SiO2/polymer combined superhydrophobic coating. The preparation method comprises the following steps: adding a polymer into an organic solvent, and stirring till the polymer is dissolved completely to obtain a transparent solution I; adding hydrophobic nano silicon dioxide and a coupling agent, continuing stirring or carrying out ultrasonic dispersion till hydrophobic nano silicon dioxide is dispersed uniformly, adopting a pulling film forming method to obtain a uniform superhydrophobic coating, and drying the superhydrophobic coating at room temperature to obtain the product, wherein the addition proportion of the polymer to the organic solvent, hydrophobic nano silicon dioxide and the coupling agent is 1.6g:(40 to 50ml):(2.0 to 2.4g):1.0g. The preparation method has the advantages that the operation is simple; the raw materials are cheap and highly available; the repeatability is high; the prepared product has the advantages of both the polymer and inorganic nano particles, and is excellent in performance; each contact angle between the prepared product and water is 160 degrees or above; the roll angle of a water droplet on the surface of the coating is equal to or smaller than 10 degrees; a film made of the coating is uniform and suitable for various substrates.