Millisecond-range time-resolved small-angle x-ray scattering studies of micellar transformations.

The transformation of mixtures of cationic and anionic micelles to vesicles has been studied by time-resolved small-angle x-ray scattering (SAXS). Equimolar amounts of ionic surfactant solutions, the anionic TexaponN70-H and the cationic TTAOH, were mixed by a stopped-flow device. Time-resolved SAXS patterns reveal that within the mixing time (<10 ms) mixed micelles are formed. These globular micelles dissolve within about 400-1000 ms and form monodisperse unilamellar vesicles in a much slower process of 5-100 s duration.