Micelles and aggregates of fluorinated surfactants

The formation of micelles and aggregates by three kinds of fluorinated surfactants has been studied by F-19 NMR, light scattering, microscopy, centrifugation, conductance measurement, and pH titration. The surfactants studied are perfluoroheptanoic acid, its salts, and its ethoxylated amides. By the use of F-19 NMR, the mean lifetime of the surfactant molecules exchanging between the monomeric state and the aggregated state was found to be about 10 −6 s for the salts, 10 −4 s for the acid, and 10 −1 s for the amides