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Failure of microemulsion models to exhibit a triple line in two dimensions
Phys. Rev. E 48, 2292 – Published 1 September, 1993
DOI: https://doi.org/10.1103/PhysRevE.48.2292
Abstract
Evidence has recently been presented [P. A. Slotte, Phys. Rev. A 46, 6469 (1992)] showing that a two-dimensional lattice model for water-oil-surfactant mixtures exhibits a triple line along which water-rich, oil-rich, and microemulsion phases coexist. We present an argument and numerical evidence that such a triple line will not exist if the efficiency of the surfactant is sufficient to produce a lamellar phase. The failure of the model to produce a triple line for an efficient surfactant can be linked to the fact that the surfactant monolayers separating regions of water and oil are only one dimensional. The implication is that two-dimensional models are somewhat inappropriate for modeling the amphiphilic behavior of real three-dimensional ternary mixtures.
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