engleski

Interactions in Mixtures of Alkylammonium chlorides and sodium cholate

Interactions in aqueous mixtures of the cationic surfactant (n-alkylammonium chlorides) and anionic surfactant (sodium cholate) have been investigated by surface tension, conductivity, microelectrophoretic and light scattering measurements as well as by optical microscopy. Investigated mixtures display interesting interfacial and phase behavior properties ; i.e. strong synergistic effects were observed for both their interfacial and bulk properties. Competition between various molecular interactions (hydrophobic, electrostatic, van der Waals, hydration forces, etc.) may result in mixed monolayer at the air/solution interface and variety of microstructures, catanionic surfactant salts, catanionic mixed micelles, catanionic vesicles, etc. in bulk phase. Adsorption at the air/solution interface and phase behavior strongly depend on the surfactant mixing molar ratio, the total concentration and molecular structure. The formation and stability of different phases are discussed in terms of surfactant molecular packing constraints and electrostatic interactions. Oppositely charged surfactants mixed non-ideally in both mixed monolayer and in the mixed micelles. The regular solution theory was used for evaluating the non-ideal interactions between surfactant molecules in adsorbed and micellar state.

alkylammonium chloride; sodium cholate; catanionic mixtures

nije evidentirano