The high-frequency dielectric response of AOT reverse micelles in n-heptane and CCl4 has been measured in the range 0.0120 GHz as a function of the water-surfactant ratio (W). A relaxation phenomenon has been observed which is connected to the single particle dynamics. This dielectric relaxation depends on surfactant hydration and is markedly affected by interparticle interactions. At low values of the volume fraction of dispersed matter water AOT, interparticle interactions are negligible and the behavior of the dielectric relaxation vs W has been interpreted in terms of two coexisting diffusion mechanisms: the reorientation of the whole micelle and the ‘‘free’’ diffusion of the completely hydrated AOT ion pairs. As is increased, inter- particle interactions start to play a role and the dielectric relaxation is considerably affected by the nature of the external oil and by the addition of small amounts of electrolyte. S1063-651X9603007-3
Dynamics of water-containing sodium bis (2-ethylhexyl)sulfosuccinate (AOT) reverse micelles: A high frequency dielectric study
FIORETTO, Daniele;ONORI, Giuseppe;PALMIERI, Luciano;SANTUCCI, Aldo
1996
Abstract
The high-frequency dielectric response of AOT reverse micelles in n-heptane and CCl4 has been measured in the range 0.0120 GHz as a function of the water-surfactant ratio (W). A relaxation phenomenon has been observed which is connected to the single particle dynamics. This dielectric relaxation depends on surfactant hydration and is markedly affected by interparticle interactions. At low values of the volume fraction of dispersed matter water AOT, interparticle interactions are negligible and the behavior of the dielectric relaxation vs W has been interpreted in terms of two coexisting diffusion mechanisms: the reorientation of the whole micelle and the ‘‘free’’ diffusion of the completely hydrated AOT ion pairs. As is increased, inter- particle interactions start to play a role and the dielectric relaxation is considerably affected by the nature of the external oil and by the addition of small amounts of electrolyte. S1063-651X9603007-3I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
