Highly polar linkers (urea, carbamate, thiocarbamate) for superoleophobic/superhydrophobic or oleophobic/hydrophilic properties
Résumé
Due to the much lower surface tension of oils in comparison to water, it is extremely difficult to obtain superoleophobic properties and also both oleophobic and hydrophilic properties. While the obtaining of superoleophobic properties needs extremely complex surface structures such as re-entrant structures to impede the oil wetting, the obtaining of both oleophobic and hydrophilic properties needs the use of both oleophobic materials (fluorinated materials) and hydrophilic materials (charged or polar species). Here, by electropolymerization of original 3,4-ethylenedioxythiophene derivatives containing both fluorinated chains (C8F17, C6F13 or C4F9) and highly polar linkers (thiocarbamate SCONH, carbamate OCONH and urea NHCONH), we report for the first time the possibility to obtain superoleophobic properties and also both oleophobic and hydrophilic properties. More precisely superoleophobic properties are obtained with different fluorinated chain lengths and linkers while the obtaining of both oleophobic and hydrophilic properties is possible only with the most polar urea NHCONH linkers.