Role of Interaction Energies in the Behavior of Mixed Surfactant Systems: A Lattice Monte Carlo Simulation

Abstract

We have investigated micellization in systems containing two surfactant molecules with the same structure using a lattice Monte Carlo simulation method. For the binary systems containing two surfactants, we have varied the head-head interactions or tail-tail repulsions in order to mimic the nonideal behavior of mixed surfactant systems and to manipulate the net interactions between surfactant molecules. The simulation results indicate that interactions between headgroups or tailgroups have an effect on thermodynamic properties such as the mixed critical micelle concentration (cmc), distribution of aggregates, shape of the aggregates, and composition of the micelles formed. Moreover, we have compared the simulation results with estimates based on regular solution theory, a mean-field theory, to determine the applicability of this theory to the nonideal mixed surfactant systems. We have found that the simulation results agree reasonable well with regular solution theory for the systems with attractions between headgroups and repulsions between tailgroups. However, the large discrepancies observed for the systems with head-head repulsions could be attributed to the disregarding of the correlation effect on the interaction among surfactant molecules and the nonrandom mixing effect in the theory.

Molecular array behavior and synergistic effect of sodium alcohol ether sulphate and carboxyl betaine/sulfobetaine in foam film under high salt conditions

“…[1][2][3][4][5][6][7]. Considerable studies have shown that the mixed surfactant systems often have better performance than mono surfactant systems from both physicochemical perspective and the point of view of application, and the study about the synergistic effects of mixed surfactants is drawing more and more attentions [8][9][10][11].…”

Mixed Micellization of Sodium Dodecylbenzene Sulfonate with Polyoxyethylene Lauryl Ether Surfactants (POLE4 and POLE23) in n‐Butanol Aqueous Solution

“…When the measured conductivity of the solution is plotted as a function of total surfactant concentration, two different straight lines with different slopes are obtained. The intercept of these lines is taken as the critical micelle concentration (CMC) and the slope ratio allows the counterion binding constant B value to be determined [10][11][12][13].…”

“…Subsequently, the adaptation of regular solution theory, where the departure from the ideal is parameterized by a single interaction parameter (b), has formed the basis of the theoretical study of mixed surfactant solutions [10][11][12][13]. In this work, we present studies on the micellization of mixtures of sodium dodecylbenzenesulfonate with polyoxyethylene(4) lauryl ether (DBS/POLE4) as well as with polyoxyethylene(23) lauryl ether (DBS/POLOE23) in aqueous solution, eventually containing n-butanol (0, 0.1, and 0.2 M).…”

Surfactant–Amino Acid and Surfactant–Surfactant Interactions in Aqueous Medium: a Review

“…Many experimental studies have been carried out using a variety of techniques on the micellization of mixed surfactant systems. The ideal solution approach has been used to interpret the properties of mixed micellar system and the adaptation of regular solution theory, where the departure from the ideal is calculated by a single interaction parameter (β), thus has put the foundation of the theoretical study of mixed surfactant solutions [158][159][160][161].…”