Preparation and performance of self‐healing nanocomposite coating with hydrophobic self‐cleaning ability

Abstract With the rapid development of today's society, hydrophobic materials are widely used in many fields due to their excellent hydrophobicity. This article presents a nanocomposite coating with self‐cleaning and self‐healing properties. The nanoparticles (TiO₂) were prepared by hydrothermal method, and the TiO₂ was hydrophobically modified by adjusting the content of stearic acid (SA) and compounded with a synthetic self‐healing silicone‐containing polyurethane (SiPU). A self‐healing nanocomposite coating (SA‐TiO₂/SiPU) with hydrophobic self‐cleaning capability was obtained by a simple brushing technique, with a water contact angle of up to 135.1° and good mechanical properties, reaching a maximum tensile strength of 3.11 MPa and a maximum elongation of 537%, and a repair efficiency of 89.39% after 12 h of fracture repair at room temperature. The self‐healing properties and stability of the coating can increase the service life of the coating, and the self‐cleaning properties can also effectively prevent contaminants from adhering to the surface; its excellent performance has the potential for a wide range of practical applications. Highlights An environmentally self‐cleaning composite coating (SA‐TiO₂/SiPU) was prepared in this study. The preparation method of the hydrophobic composite coating is simple. The micro‐nano structure of SA‐TiO₂/SiPU is critical for its hydrophobicity. The SA‐TiO₂/SiPU coating with good self‐healing properties. The SA‐TiO₂/SiPU exhibited excellent durability and self‐cleaning properties.