Phase behavior of the perfluoropolyether microemulsion in supercritical CO2 and their use for the solubilization of ionic dyes

Phase behavior of the perfluoropolyether surfactant microemulsion in supercritical CO₂ and the solubilization of conventional ionic dyes in the same system have been investigated using Perfluoro 2,5,8,11-tetramethyl-3,6,9,12-tetraoxapentadecanoic acid ammonium salt. We found that the surfactant prepared in this study was satisfactorily dissolved in supercritical CO₂ without the presence of entrainer. Moreover dissolved surfactant had an ability to form micellar aggregates and to incorporate a small amount of water in the interior of aggregates. We also found that conventional ionic dyes such as acid dye, reactive dye and basic dye were solubilized in the microemulsion system in supercritical CO₂.