Influence of long alkyl spacers in the elaboration of superoleophobic surfaces with short fluorinated chains

Abstract

International audienceIn order to produce extremely high oleophobic properties with a low fluorine content, long dodecyl spacers were introduced between a polymer and fluorinated chains in order to reduce the mobility of the fluorinated chains, especially short perfluorobutyl (F-butyl) chains. We report the synthesis and characterization of electrodeposited polymer surfaces obtained from original fluorinated 3,4-ethylenedioxypyrrole (EDOP) derivatives. Semi-fluorinated chains of three different lengths (F-octyl: PEDOPC12F8, F-hexyl: PEDOPC12F6 and F-butyl: PEDOPC12F4) were grafted to EDOP and separated with a n-dodecyl chain in order to reduce the mobility of F-butyl chains. For the first time, a surprisingly high contact angle of 138u was measured with hexadecane on PEDOPC12F4, although F-octyl tails are necessary to produce robust superoleophobic surfaces. By producing smooth surfaces, we successfully separate the influence of the intrinsic hydro- and oleophobicity and the surface structuration on the static contact angles of water and hexadecane. Here, the surface structuration increases the contact angle of hexadecane by 90u for PEDOPC12F4. The Cassie-Baxter equation predicts a porosity of 84.5% between the surface and a hexadecane droplet

CH-π Interaction Driven Macroscopic Property Transition on Smart Polymer Surface

“…S10 and Table S3 for more details). These data reveal the adsorption of FFF leads to a slight swelling of the copolymer film, resulting in the reduction of surface roughness, which contributes to surface wettability change to some extent 45 .…”

“…6 ) 51 , which results in a contracted conformation for the copolymer chains and a relatively hydrophobic property for the copolymer film. Moreover, the presence of CF 3 groups in PT units may further enhance the initial surface hydrophobicity 45 . Then, when being immersed in tripeptide FFF solution, monosaccharide Glc units in copolymer chains combine the aromatic rings of FFF and form complexes via CH-π interaction (interaction model was shown in Fig.…”

Highly Oleophobic Properties of PEDOP Polymers with Short Perfluorobutyl Chains Separated by Long Alkyl Spacers and Amido Connectors

“…The highly oleophobic properties obtained with F -butyl tails confi rm the importance to have a long alkyl spacers between the polymer and the fl uorinated chains. [ 14 ] Hence, as confi rm by cyclic voltammetry, due to high van der Waals interactions between long alkyl spacers, the mobility of the F -butyl chains is highly reduced, which allows their presence at the extreme surface to be increased and as a consequence the oil-repellent properties. Indeed, usually an important surface segregation is often obtained using relatively long fl uorinated tails (above 6-7 methylene units) because of strong interactions between these chains.…”

“…It was demonstrated that the use of fl uorinated 3,4-ethylenedioxypyrrole (EDOP) derivatives as monomer allowed superoleophobic properties to be reached. [11][12][13][14] They often led to nanoporous/nanostructured surfaces, which was a key parameter in the elaboration of superoleophobic properties. However, it was demonstrated, by cyclic voltammetry experiments, that the formation of surface nanoporosity is highly sensitive to the monomer structure and that the polymer should be very planar to induce this formation.…”

A bioinspired approach to produce parahydrophobic properties using PEDOP conducting polymers with branched alkyl chains

“…The 3,4-ethylenedioxypyrrole (EDOP) heterocycle is an excellent core with exceptional polymerization capacity associated to excellent optical and electrical properties [25,26]. Moreover, it was also shown the possibility to obtain very specific surface structures with exceptional wettability properties, such as nanoporous structures [27][28][29][30][31][32][33][34]. For example, superhydrophobic or superoleophobic properties were obtained using linear hydrocarbon and fluorocarbon chains, respectively.…”