Multifunctional Superhydrophobic Polymer/Carbon Nanocomposites: Graphene, Carbon Nanotubes, or Carbon Black?

Abstract

Superhydrophobic surfaces resisting water penetration into their texture under dynamic impact conditions and offering simultaneously additional functionalities can find use in a multitude of applications. We present a facile, environmentally benign, and economical fabrication of highly electrically conductive, polymer-based superhydrophobic coatings, with impressive ability to resist dynamic water impalement through droplet impact. To impart electrical conductivity, the coatings were prepared by drop casting suspensions with loadings of different kinds of carbon nanoparticles, namely, carbon black (CB), carbon nanotubes (CNT), graphene nanoplatelets (GNP) and their combinations, in a fluoropolymer dispersion. At 50 wt % either CB or CNT, the nanocomposite coatings resisted impalement by water drops impacting at 3.7 m/s, the highest attainable speed in our setup. However, when tested with 5 vol % isopropyl alcohol-water mixture, i.e., a lower surface tension liquid posing a stiffer challenge with respect to impalement, only the CB coatings retained their impalement resistance behavior. GNP-based surfaces featured very high conductivity ∼1000 S/m, but the lowest resistance to water impalement. The optimal performance was obtained by combining the carbon fillers. Coatings containing CB:GNP:polymer = 1:1:2 showed both excellent impalement resistance (up to 3.5 m/s with 5 vol % IPA-water mixture drops) and electrical conductivity (∼1000 S/m). All coatings exhibited superhydrophobic and oleophilic behavior. To exemplify the additional benefit coming from this property, the CB and the optimal, combined CB/GNP coatings were used to separate mineral oil and water through filtration of their mixture.

Comb‐like polymer‐graphene nanocomposites with improved adhesion properties via surface‐initiated atom transfer radical polymerization (SI‐ATRP)

“…The contact angle of a liquid on solid surface is influenced by surface roughness, surface heterogeneity (microscopic areas of differing surface energies), or restructuring of molecules at the solid surface . Hydrophobic surfaces that resist water penetration into their texture and simultaneously offering additional functionalities are important for a multitude of applications . The sheet‐like morphology observed in SEM image of films modified with graphene might be attributed to surface roughness.…”

Nanocomposite Coatings: Preparation, Characterization, Properties, and Applications

“…For organic matrix, called polymer-based nanocomposite, the most used polymers for preparation of nanocomposite coating can be listed as follows: epoxy [2][3][4][5][6][7], polyurethane [8,9], Chitosan [10,11], polyethylene glycol (PEG) [12][13][14][15], polyvinylidene fluoride (PVDF) [16], PANi [17][18][19], PPy [20][21][22][23], polystyrene [24], polyamic acid and polyimide [25], rubber-modified polybenzoxazine (PBZ) [26], polymers containing reactive trimethoxysilyl (TMOS) [27], pullulan [28], fluoroacrylic polymer [29,30], ethylene tetrafluoroethylene (ETFE) [31], polyacrylate [3], poly(N-vinyl carbazole) [32], polycarbonate [33], fluorinated polysiloxane [34], polyester [35], polyacrylic [36], polyvinyl alcohol (PVA) [37], polydimethylsiloxane [38], polyamide [39], and UV-curable polymers [40].…”

Recent Advances in the Fabrication of Superhydrophobic Surfaces

“…The similar requirements like the above would be addressed to a large extent. Taking the multifunctional superhydrophobic nanocomposites as an example, the superhydrophobic texture resisting water under dynamic water impact conditions has been reported by Poulikakos et al 145 They prepared four setups of superhydrophobic texture resisting dynamic water impact conditions based on multifunctional polymer/carbon nanocomposites, namely graphene nanoplatelets (GNP), CNT, carbon black (CB), and the combinations in the fluoropolymer dispersions. The critical impalement velocity of different setups was tested.…”

“…38,149 At present, research about special wettability materials for oil/water separation has attracted much interest of scientific workers and has been reported in many publications. 23,32,38,39,51,80,113,145,150154 As a typical example, Jiang et al prepared the superhydrophobic and superoleophilic Teflon-coated mesh for oil/water separation for the first time in 2004. 153 Since then novel functional surfaces with extreme wettability have been widely investigated.…”