Experimental Evidence for Random Surface Structures in Dilute Surfactant Solutions

Abstract

Anomalous flow birefringent phases, sometimes designated as L3, have been identified in both the water-rich and the oil-rich parts of the phase diagram of the water(NaCl)-dodecane-pentanol-SDS system. The presence of these phases appears to be associated with that of swollen lamellar phases. Conductivity and neutron scattering results provide evidence that the structure of these phases consists of a highly connected, spongelike, random bilayer-continuous surface. The surfactant surface separates, depending upont the system, either two water-continuous domains or two oil-continuous domains. The data are consistent with a recent theoretical models.