Adsorption dynamics of micellar solutions of a mixed anionic–cationic surfactant system

The influence of micellar dissolution processes on the dynamic surface tensions of micellar solutions of SDS and SDS–DTAB mixtures was investigated by bubble pressure tensiometry. Based on a kinetic model the micelle dissociation constants are determined from dynamic surface tension data. The calculated micelle dissociation constants of SDS were in the range between 260 and 1600 s−1, i.e., the slow relaxation time for the SDS micelle dissociation process was in the range between 0.004 and 0.0006 s. These results are in good agreement with the experimental data for SDS (slow relaxation process), obtained by others using different methods. The calculated micelle dissociation constants of the SDS–DTAB complex were in the range between 0.3 and 30 s−1.