FORMATION OF INTERFACES IN BICONTINUOUS PHASES

With the charge-frustrated model, this paper examines the structure of interfaces in bicontinuous oil-water-surfactant phases. We analyze the nonlinear model by variational perturbation theory with a reference system that explicitly allows for interfaces. On the length scales consistent with a microscopic length cutoff, the theory predicts distinct microphase separation for some systems that have been considered bicontinuous. For other systems, for which experimentalists have imagined microphase separation but not bicontinuity, the theory predicts near homogeneity, i.e., highly diffuse interfaces.