Rheology of mixed solutions of sulfonated methyl esters and betaine in relation to the growth of giant micelles and shampoo applications

Abstract

This is a review article on the rheological properties of mixed solutions of sulfonated methyl esters (SME) and cocamidopropyl betaine (CAPB), which are related to the synergistic growth of giant micelles. Effects of additives, such as fatty alcohols, cocamide monoethanolamine (CMEA) and salt, which are expected to boost the growth of wormlike micelles, are studied. We report and systematize the most significant observed effects with an emphasis on the interpretation at molecular level and understanding the rheological behavior of these systems. The experiments show that the mixing of SME and CAPB produces a significant rise of viscosity, which is greater than in the mixed solutions of sodium dodecyl sulfate and CAPB. The addition of fatty alcohols, CMEA and cationic polymer, leads to broadening of the synergistic peak in viscosity without any pronounced effect on its height. The addition of NaCl leads to a typical salt curve with high maximum, but in the presence of dodecanol this maximum is much lower. At lower salt concentrations, the fatty alcohol acts as a thickener, whereas at higher salt concentrations -as a thinning agent. Depending on the shape of the frequency dependences of the measured storage and loss moduli, G' and G", the investigated micellar solutions behave as systems of standard or nonstandard rheological behavior. The systems with standard behavior obey the Maxwell viscoelastic model (at least) up to the crossover point (G' = G") and can be analyzed in terms of the Cates reptationreaction model. The systems with nonstandard rheological behavior obey the Maxwell model only in a restricted domain below the crossover frequency; they can be analyzed in the framework of an augmented version of the Maxwell model. The methodology for data analysis and interpretation could be applied to any other viscoelastic micellar system.

Cleaning Ability of Mixed Solutions of Sulfonated Fatty Acid Methyl Esters

“…Mixing of amine‐oxide surfactants with anionic surfactants is known to boost the growth of wormlike micelles in the bulk of solution (Hoffmann et al, ). In particular, the mixing of SME with the zwitterionic surfactant cocamidopropyl betaine (with or without added electrolyte) produces a strong synergistic effect on the micelle growth in the bulk (Yavrukova et al, ). The present results on cleaning indicate that the mixing of SME with the zwitterionic DDAO could promote also the formation of admicelles on the surface of stainless steel.…”

“…The mixing of anionic SME with a zwitterionic surfactant gives rise to the growth of giant wormlike micelles in the bulk of surfactant solution (Basheva et al, ; Yavrukova et al, ). The results in Fig.…”

pH-Responsive Rheological Properties and Microstructure Transition in Mixture of Anionic Gemini/Cationic Monomeric Surfactants

“…The wormlike micelles formed by surfactant solutions have been widely investigated, due to their good detergency, unique viscoelastic properties, and their large application potential [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. Above a critical concentration C *, wormlike micelles can entangle into a transient network, just like flexible polymer solutions, endowing the surfactant solutions with remarkable viscoelastic properties.…”

“…Normally, surfactants with a packing parameter of 1/3~1/2 are favorable for micellar growth [ 1 , 2 , 3 , 4 , 5 ]. For this purpose, considerable efforts have been devoted to construct wormlike micelles through controlling the inter/intramolecular interactions [ 6 , 7 , 8 , 9 , 10 ]. The variation of molecular interactions minimizes the headgroup area, induces lower spontaneous curvature and promotes micellar growth.…”

Adsorption of Equimolar Mixtures of Cationic and Anionic Surfactants at the Water/Hexane Interface

“…Although the respective bulk mixtures were extensively investigated many years ago [10,11], the properties of the resulting interfacial adsorption layers, such as their foam stabilizing capabilities, cannot be predicted from the bulk behavior alone [12]. These paired surfactants are, however, of great interest, because they are effectively double-tailed (and therefore lipid-like) surface active molecules and suitable for numerous applications in pharmacy [4], drug delivery [13,14], vesicle formation [15,16] or cosmetics [17] and can be combined with ionic liquids [18,19]. A systematic study of catanionics adsorbed at liquid interfaces is therefore of great importance.…”