Journal of Colloid and Interface Science, Vol.553, 778-787, 2019
A universal fluorous technology toward superhydrophobic coatings
Hypothesis: Development of a process yielding large-sized non-wettable coatings of immediate applicative interest seems feasible by associating a membrane spining technique with the artificial mimic of a bio-inspired strategy toward water repellency. Accordingly, the question that arises is how to design a multiscale textured and chemically-activated continuous film. Experiments: A novel synergic combination of a processing technique and chemical treatment was developed in this purpose. Fluorinated nanocarbons were included in polyvinylpyrrolidone (PVP) microfibers via their addition in a precursor solution for electrospinning. The nanocomposites thus obtained were subsequently treated under gaseous molecular fluorine in mild conditions. Findings: Owing to the reactivity of PVP with F-2, both etching and functionalization occurred during such a post-treatment. The chemical modification undergone by PVP upon fluorination has been analyzed and a mechanistic approach proposed. An impressive dual texturing developed at the micro- and nanoscale thanks to the combined action of electrospinning, polymer etching and emergence of the nanofillers. This allowed a stable with time superhydrophobic coating-like film to be achieved. (C) 2019 Elsevier Inc. All rights reserved.