Superhydrophobic and mechanically robust polysiloxane composite coatings containing modified silica nanoparticles and PS-grafted halloysite nanotubes

Excellent mechanical properties are the prerequisite for the application of superhydrophobic polymer coatings. However, significantly improving the mechanical properties without affecting other properties such as hydrophobicity is a huge challenge. In this study, a superhydrophobic coating with excellent mechanical properties was prepared by spraying a mixture of polysiloxane resins based on three siloxane monomers, hexadecyltrimethoxysilane (HDTMS) modified nano-SiO2 particles (SiO2-HDTMS) and polystyrene-grafted halloysite nanotubes (HNTs-PS). SiO2-HDTMS dispersed homogeneously in polysiloxane coatings and the water contact angle of corresponding coating exceeding 150°, achieving superhydrophobicity. The SiO2-HDTMS/HNTs-PS/polysiloxane composite coatings showed excellent abrasion resistance with the water coating contact angle remaining above 150° after 90 abrasion cycles, indicating that HNTs-PS can significantly improve the mechanical properties of the coating without affecting the hydrophobic properties of the coating. The achieved coating also exhibited excellent antifouling and acid and alkali corrosion resistance. This work provides a convenient and ecologically friendly method to prepare superhydrophobic polysiloxane composite coating with excellent mechanical properties, which is promising in the application of anti-fouling, anti-corrosion, and oil–water separation etc.