Effects of Protonation of Alkyldimethylamine Oxides on the Dissolution Temperature in Aqueous Media

Vesicle−Micelle Transition and the Stability of the Vesicle Dispersion in Mixtures of Tetradecyldimethylamine Oxide Hemihydrochloride and Sodium Naphthalenesulfonate

“…the degree of protonation α ) depends on the pH of the solution. Evidence for a short-range attractive interaction between the nonionic and the cationic headgroups has been suggested in the solid state, , in the micelles in solution, , and in adsorbed films at the solid−solution interface. , Reversible vesicle formation from threadlike micelles was observed to occur in oleyldimethylamine oxide aqueous solutions by changing pH . The short-range attractive interaction has been suggested to be a hydrogen bond between the nonionic and the cationic headgroups. − Support for the proposed hydrogen bond has been found from infrared spectroscopy …”

Temperature-induced sedimentation to dispersion of ionic vesicles

“…The relative population of the two components (i.e., the degree of protonation α) depends on the pH of the solution. Evidence for a short-range attractive interaction between the nonionic and the cationic head groups has been found in the solid state [17], in micellar solution [18], and in adsorbed films at the solid-solution interface [19]. The short-range attractive interaction has been suggested to be a hydrogen bond between the nonionic and the cationic head groups (-N + -OH· · ·O-N-) [20][21][22][23].…”

“…For the mixture of C16TAB with sodium 3-hydroxynaphthalene-2-carboxylate (SHNC), which almost completely binds to the micelle surface, a vesicular phase was found in the equimolar solution [13][14][15][16][17]. Cetyltrimethylammonium hydroxynaphthalene carboxylate (C16TAHNC), obtained from an equimolar mixture of C16TAB with SHNC, formed vesicles at room temperature.…”

Counterion specificity in the phase behavior of tetradecyldimethylamine oxides at different degrees of protonation

“…In the vesicle or lamella formation induced by the binding of an aromatic counterion, different behaviors have been observed depending on the degree of protonation [6]. The synergism has been observed not only in solutions but also on the Krafft boundary [7], aggregates at solid/solution interfaces [8], and solid state [9]. The synergism has been ascribed to a hydrogen bond between the protonated and the non-protonated head groups [2] and this hydrogen bond is supported by an infrared absorption study [10].…”