Superhydrophobic conducting polymers with switchable water and oil repellency by voltage and ion exchange
Résumé
In order to elaborate superhydrophobic polymers with switchable water and oil-repellency, copolymers are prepared by electrodeposition. A fluorinated monomer (EDOT-F8) is used to reach superhydrophobic properties and a monomer containing an ammonium function (EDOT-N+) to induce changes in the surface wettability by ion exchange. We also study the change in the surface wettability by dedoping at a different voltage. Surprisingly, an increase in the water and oil repellency was observed by introduction of hydrophilic monomers (EDOT-N+), which is due to a modification in the surface morphology and more precisely to the presence of small spherical particles containing thin fibrils on their surface (multi-scale roughness). The dedoping and the ion exchange (ClO4- by BF4-, Tf2N- or C8F17SO3-) modify especially the oil-repellency. Here, the highest oleophobic properties are obtained with the inorganic ions (ClO4- and BF4-).