Facile Preparation of Robust Superamphiphobic Coatings on Complex Substrates via Nonsolvent-Induced Phase Separation

Superamphiphobic surfaces have great potential in many fields but often suffer from complicated, expensive, and time-consuming preparation methods, difficulty in applying them on complex substrates, and low stability. Herein, we show a facile fabrication of robust superamphiphobic coatings on complex substrates. A stock suspension was prepared by nonsolvent-induced phase separation of a silicone-modified polyurethane (Si-PU) adhesive containing fluorinated silica (FD-silica) nanoparticles. Then, superamphiphobic surfaces could be easily fabricated via dip coating in the suspension. The influences of phase separation and Si-PU/FD-silica ratio on the wettability and morphology of the coatings were studied. The coatings feature a microscale dense and nanoscale rough texture due to phase separation and rapid solvent evaporation, which enhances the stability by forming strong linkages among the nanoparticles while achieving high superamphiphobicity by trapping air stably in the nanopores. Consequently, the coatings show excellent static/dynamic superamphiphobicity, superior impalement resistance, and good mechanical, chemical, thermal, and UV aging stability. Additionally, the coatings have good anti-icing performance as demonstrated by the greatly extended water freezing time and weakened ice adhesion force in both simulated and real conditions.