Characterization of mixed nonionic surfactant micelles by photon correlation spectroscopy and viscosity

Abstract Mixed micelles of the nonionic surfactants Brij 92 and Brij 96 were shown to be large and asymmetric. Using the relationship between the radius of gyration (from total intensity light-scattering dissymmetry measurements) and the hydrodynamic radius (from photon correlation spectroscopy) the mixed micelles are shown to have a rod-like structure, the length of which increases with temperature and on addition of salt. These rod-like micelles appear to exhibit considerable flexibility which is responsible for their measured viscosities being less than that expected from their asymmetry.