Synthesis of superhydrophobic FAS-EP/PTFE coating with excellent drag reduction performance and mechanical robustness

Superhydrophobic (SHP) materials have great potential for applications in self-cleaning, anti-fouling, anti-corrosion and drag reduction, but their poor mechanical robustness is a fundamental problem that hinders their practical application. In this work, we successfully and rapidly prepared SHP coating with good durability and drag reduction properties by a simple drop-coating technique after chemical modification and physical mixing. We investigated the effects of modification with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane (FAS-17), a low surface free energy material, and the filling content of Poly tetra fluoroethylene (PTFE) on the hydrophobic property of the as-prepared coating. The maximum water contact angle (WCA) and the minimum sliding angle (SA) of the coating were 160.2 ± 0.4° and 5°, respectively. The coating maintained superhydrophobicity after 4.4 m of abrasion with 400 grit sandpaper and 3 h of water impact, indicating its excellent mechanical durability. In addition, it has outstanding self-cleaning and self-repairing properties. Moreover, the coating was innovatively applied to the surface of the chute, because it remarkably reduced the adhesion between the wet foam block and the chute. These findings here provide a novel insight into the design of a robust SHP coating and suggest a new potential application in express sorting industry for drag reduction.