Superoleophobic and conductive carbon nanofiber/fluoropolymer composite films

Abstract

A solution-based, large-area coating procedure is developed to produce conductive polymer composite films consisting of hollow-core carbon nanofibers (CNFs) and a fluoroacrylic copolymer available as a water-based dispersion. CNFs (100nm dia., length ~130µm) were dispersed by sonication in a formic acid/acetone co-solvent system, which enabled colloidal stability and direct blending of the CNFs and aqueous fluoroacrylic dispersions in the absence of surfactants. The dispersions were sprayed on smooth and microtextured surfaces, thus forming conformal coatings after drying. Nanostructured composite films of different degrees of oil and water repellency were fabricated by varying the concentration of CNFs. The effect of substrate texture and CNF content on oil/water repellency was studied. Water and oil static contact angles (CA) ranged from 98° to 164° and from 61° to 164°, respectively. Some coatings with the highest water/oil CAs displayed self-cleaning behavior (droplet roll-off angles < 10°).

Superamphiphobic surfaces

“…Moreover, by controlling the dose of UV illumination, superphobicity and superphilicity can exist on the same surface for probing liquids with different surface tensions. Except nanosilica and carbon nanotubes, carbon nanoparticles such as carbon nanofibers, 28 fullerene, graphene as well as other 45 inorganic particles such as nano ZnO 2 , CuO, Ca(OH) 2 and CaCO 3 has also been reported to generate surface roughness (see the related references in ref. 25).…”

Recent developments in polymeric superoleophobic surfaces

“…They prepared a CNF/polymer dispersion, which can be easily coated on substrates using a spray process. 126 Wang et al further introduced electrically conductive superoleophobic coatings to fabrics (Fig. 7).…”

Designing bioinspired superoleophobic surfaces

“…However, not only was hysteresis not reported but lower surface tension liquids were not tested and no durability experiments were performed. 14 Fluoropolymers have also been used with electrodeposited conductive polymers, 15 ZnO nanoparticles, 16 polydimethylsiloxane (PDMS) trapezoids, 17 silica particles, 18 carbon nanofibers, 19 silicamodified fabrics, 20 raspberry-shaped particles, 21 and electrospun copolymers 22 to result in oleophobic or superoleophobic surfaces. Fluoropolymers have also been spray cast with fluorinated silica particles resulting in good repellency towards water, diiodomethane, rapeseed oil, and hexadecane.…”