Article révisé par les pairs
Résumé : Some correction are made to previous calculations on spontaneous interfacial convection driven by differences in surfactant adsorption on liquid-liquid interfaces. When those corrections are applied in the computer calculations, the previously reported differences between the dispersion curves with the Sternling-Scriven model and that of the present authors at low surface tension disappear in the case of a linear concentration profile. With exponential profiles, simulating profiles of the erf-type, there is still found a destabilisation for low interfacial tensions which might be a mechanism active in spontaneous emulsification phenomena. The influence of decreasing the thickness of the concentration zone while keeping the interfacial transfer of substance constant is a stabilising one, for oscillatory as well as non-oscillatory instabilities due to the decreasing concentration difference between surfactant in the two liquid phases. The Sternling-Scriven formalism is modified to cover the case of exponential profiles. In cases with not too low surface tensions (above 1 dyne cm-1) this model gives the same results as the Lyngby approach, i.e., effects due to interfacial deformation, gravity and absolute value of the surface tension are often unimportant.