Preparation of superamphiphobic robust film
In a new study, composite of dual-sized porous silica of micro-/nanoparticles and epoxy resin was coated on the glassy substrate as the micro-/nanostructure, then 60 nm porous silica particles modified by 3-aminopropyltriethoxysilane were covered on it.
The monolayer of low-surface-energy fluoride-chains was grafted by click reaction of 2-(((3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10- heptadecafluorodecyl)-oxy)-methyl)oxirane with amino groups in the micro-/nanostructure surface. The low free-energy long perfluorinated chain and topological features established a super-repellent surface. The surface was of the superamphiphobic property with a wide range of liquids (surface tension ranging from 72.0 to 27.2 mN m−1).
Use in outdoor and large-scale fabrications
Because of EP’s wearability and the long perfluorinated chains’ automatically migrating from the inner surface of porous silica particles to the new surface, the super-repellent surface is of not only the self-cleaning feature like the lotus’ effect, but also the durability, the self-healing and high wear-resisting abilities, even after it was heavily scratched by the knife or abraded by sandpaper.
After the superamphiphobic coating had been rubbed, under a weight of 100 g, 40 sandpaper abrasion cycles, the coating still keeps its contact angles (CAs) to water; diiodomethane and ethylene glycol over 155 ± 2°, and all its sliding angles (SAs) lower than 2.7 ± 1°, respectively. These abilities are anticipated to have important practical applications because of their satisfactory of the long-life use in outdoor and large-scale fabrications.
The study is published in: Progress in Organic Coatings Volume 117, April 2018, Pages 20-28.