Facile fabrication of self-healing superhydrophobic nanocomposite films enabled by near-infrared light

A novel robust self-healing superhydrophobic F-SiO 2 /Fe 3 O 4 /EP(epoxy)/PCL nanocomposite film was fabricated through a facile two-step method including resin spraying and NPs perpendicular gradient deposition. Specially, the epoxy/polycaprolactone (EP/PCL) mixed resin matrix was prepared through a spraying process and the functioned silica/magnetic iron oxide (F-SiO 2 /Fe 3 O 4 ) nanoparticles were then deposited on the resin matrix by gradient distribution under gravity and solvent evaporation. The THF/ethanol mixture solvent which acted as film microstructure-directing agent guided the F-SiO 2 /Fe 3 O 4 nanoparticles gradient distribution in the nanocomposite films. The results showed that the cutting cracks on the nanocomposite film could be rapidly self-healed and the film would maintain its superhydrophobicity after irradiation by near-infrared light. The nanocomposite films, especially the F-SiO 2 (8.5wt%)/Fe 3 O 4 (1.0wt%)/EP/PCL nanocomposite film, showed high resistant properties on abrasion, corrosive liquids and UV irradiation. The recovery mechanism of the nanocomposite films was also investigated.