Premium
Thermodynamics of microemulsions: Combined effects of dispersion entropy of drops and bending energy of surfactant films
Author(s) -
Miller C. A.,
Neogi P.
Publication year - 1980
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.690260204
Subject(s) - microemulsion , pulmonary surfactant , thermodynamics , drop (telecommunication) , dispersion (optics) , chemistry , curvature , phase (matter) , materials science , organic chemistry , optics , physics , telecommunications , geometry , mathematics , computer science
A theory of dilute microemulsions is presented which includes for the first time both the entropy of dispersion of the drops and energy effects associated with bending the surfactant films at the drop interfaces. It yields expressions for drop size for (a) a dilute microemulsion in equilibrium with an excess bulk phase, e.g., an oil‐in‐water microemulsion in equilibrium with excess oil and (b) dilute oil‐continuous and water‐continuous microemulsions in equilibrium and containing equal amounts of surfactant. In the latter case, our theory indicates that existence of the two microemulsion phases sometimes is favored over a layered or lamellar phase, even though the “natural curvature” of the surfactant films is zero, corresponding to a perfectly flat film.