Facile preparation of durable superhydrophobic coating with microstructure self-repairing function by spraying method

Abstract

Self-healing superhydrophobic coatings have attracted tremendous attention recently, although their practical applications are severely limited by hydrophobic instability and poor structure durability. In this study, a durable superhydrophobic coating was fabricated by a rapid micro/nano structural reconstruction strategy. Carbon nanofibers (CNF) with high aspect ratio were interspersed in fluorosilicone resin (FSR) to construct a uniform network structure. By combining with temperature-responsive carnauba wax (CW) and modified fluororubber (MFR), we obtained a superhydrophobic FSR/CNF/CW/MFR coating with a water contact angle (WCA) of 157 ± 1.2° and water sliding angle (WSA) of 4.5 ± 0.4°. Under the triple synergy of polymer segment migration of FSR, temperature-responsive phase transition of CW, and elastomer rebound repair of MFR, the damaged FSR/CNF/CW/MFR coating surface was rapidly reformed to a new hierarchical micro/nanostructure with short heat treatment (less than 120 s). As a result, for a flat surface, after 1000 abrasion cycles or falling ball impact, a rich micro/nano structure was rapidly reconstructed and superhydrophobic properties were restored. The reconstructed micro/nano multistage structure could effectively capture air, which led to the repaired area exhibiting a charming silver mirror effect and excellent self-cleaning performance. Therefore, this work is expected to provide new insight into the restoration of micro/nanostructures of durable superhydrophobic coatings.