Binary anionic surfactant mixtures

LOPATA ET AL. Adsorption of Binary Anionic Surfactant Mixtures... 

Scamehorn et. al. (19) reported the adsorption isotherms for a binary mixture of anionic surfactants. A formal adsorption model developed for single surfactant systems ( ) was extended to this binary system and shown to accurately describe the mixed adsorption isotherms (19). That theoretically based model was very complex and is probably not feasible to extend beyond two surfactant components. 

Scamehorn, J.F., Schecter, R.S. and Wade, W.H. (1982) Adsorption of surfactants on mineral oxide surfaces from aqueous solutions. II. Binary mixtures of anionic surfactants. /. Colloid Interface Sci., 85, 479-93. 

The adsorption of binary mixtures of anionic surfactants of a homologous series (sodium octyl sulfate and sodium dodecyl sulfate) on alpha aluminum oxide was measured. A thermodynamic model was developed to describe ideal mixed admicelle (adsorbed surfactant bilayer) formation, for concentrations between the critical admicelle concentration and the critical micelle concentration. Specific... 

Scamehorn et. al. expanded a single component adsorption equation ( ) to describe the adsorption of binary mixtures of anionic surfactants of a homologous series (1 1). Ideal solution theory was found to describe the system fairly well. The mixed adsorption equations worked very well in predicting the mixture adsorption, but the equations were complex and would be difficult to extend beyond a binary system. 

The adsorption of binary mixtures of anionic surfactants in the bilayer region has also been modeled by using just the pure component adsorption isotherms and ideal solution theory to describe the formation of mixed admicelles (3 ). Positive deviation from ideality in the mixed admicelle phase was reported, and the non-ideality was attributed to the planar shape of the admicelle. However, a computational error was made in comparison of the ideal solution theory equations to the experimental data, even though the theoretical equations presented were correct. Thus, the positive deviation from ideal mixed admicelle formation was in error. 

Scamehorn, J. F., R. S. Schechter, and W. H. Wade (1982b), Adsorption of Surfactants on Mineral Oxide Surfaces from Aqueous Solutions. II. Binary Mixtures of Anionic Surfactants, J. Colloid Interface Sci. 85, 479-493. 

Mixture of Anionic Surfactants onto Alumina. Most EOR surfactants are mixtures of isomers, but these mixtures are too complex for application of basic theory. In contrast, the effectiveness of ideal solution theory in explaining region II adsorption for binary mixtures of anionic surfactants has been demonstrated [5Jj. These controlled isomeric mixtures allow application of the ideal solution theory. The application of this theory utilized a reduced adsorption equation for mixtures of anionic surfactants [52]. The parameters for this reduced... 

In Chapter 1, Murgia, Palazzo, and coworkers investigated the physicochemical behaviors of a binary IL bmimBF and water, and the ternary NaAOT, water and bmimBF mixtures essentially through the evaluation of the self-diffusion coefficients of the various chemical species in solution by PGSTE-NMR experiments. The diffusion of water molecules and bmimBF ions were found to be within different domains, which suggested that the systems were nanostructured with formation of micelles having positive curvature and a bicontinuous micellar solution for the former and the later systems, respectively. The remarkable differences between the two systems are attributed to the specific counterion effect between the aforementioned ILs and the anionic surfactant. In Chapter 2, Bermudez and coworkers focused on the characterization of small (conventional surfactants) and polymeric amphiphiles (block copolymers) in different types of ILs (imidazolium, ammonium. 

Bourrel M, Bernard D, Graciaa A (1984) Properties of binary mixtures of anionic and cationic surfactants Micellization and Microemulsions. Tenside Deterg 21 311-318... 

The variation of the mixture critical micelle concentration (CMCf ) with temperature and with overall surfactant composition has been studied using ultrafiltration for two binary mixed nonionic/anionic systems. 

The simultaneous adsorption of poly(vinylpyrrolidone) (PVP) and an anionic hydrocarbon or fluorocarbon surfactant from their binary mixtures on polystyrene latex was studied by Otsuka et al [59]. The bare particles and the particles coated with PVP/surfactant were sized by sedimentation field flow fractionation (SFFF). The adsorption of PVP was enhanced by LiDS or LiFOS at low surfactant concentrations, but decreased at high surfactant concentrations. The conformation of adsorbed PVP changed from loops and trails to trains with the increasing surfactant concentration. However, in the PVP-LiFOS system, the fraction of train segments increased steeply at a lower surfactant concentration and was greater than that in the PVP-LiDS system. The thickness of the adsorbed layer was also determined by photon correlation spectroscopy after prefractionation by SFFF. The thickness of the adsorbed layer decreased with increasing surfactant concentration. (For the characterization of adsorbed surfactant layers, see Ref. 56, pp. 205-216). 

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