Mixing behavior of fluorinated and hydrogenated gemini surfactants at the air-water interface.
Mixing behavior of hydrogenated and fluorinated cationic gemini surfactants was studied at the air-water interface by Brewster angle microscopy and pi-A isotherm curves. In the bulk, these two molecules did not mix and showed phase separation. At the air-water interface, if a monolayer was formed by separate deposition of the two solutions, they formed separate domains, and the compression occurred in two steps: first the domains with hydrogenated gemini surfactant were compressed until they showed collapse; then the domains with fluorinated gemini surfactant were compressed. If the two solutions were mixed before the deposition, they remained mixed upon compression; on the other hand, separate domains under separate deposition were shown to mix if the subphase was heated.
Nishida
Jin
J
Institut Européen de Chimie et Biologie, UMR-CNRS 5144, Molécules, Biomolécules et Objets Supramolculaires (MOBIOS), 2 rue Robert Escarpit, 33607 Pessac Cedex, France.
Brizard
Aurélie
A
Desbat
Bernard
B
Oda
Reiko
R