Micellization of Anionic Sulfonate Gemini Surfactants and Their Interactions With Anionic Polyacrylamide

Abstract

Anionic sulfonate gemini surfactants 8-s-8 (SO 3 ) 2 and 12-s-12(SO 3 ) 2 (s = 3, 6) were synthesized, and their micellization in aqueous solution at 25.0 C and pH 9 was investigated. The results show that the critical micelle concentrations (CMC) of 8-s-8(SO 3 ) 2 are more than 2 orders of magnitude larger than those of 12-s-12(SO 3 ) 2 , but the spacer length has a relatively small impact on the CMC. Moreover, the interactions of n-s-n(SO 3 ) 2 (n = 8, 12; s = 3, 6) with anionic polyacrylamide (PAM) at 25.0 C and pH 9 were investigated using surface tensiometry, rheolgy, and scanning electron microscopy (SEM). The results indicate that the surface tension and rheological properties of PAM depend on the concentration of n-s-n(SO 3 ) 2 . Below the critical aggregation concentration of C 1 , surface tension is sharply reduced, the surface tension of n-s-n(SO 3 ) 2 /PAM is lower than n-s-n(SO 3 ) 2 alone, but viscosity is almost unchanged with increasing C n-s-n(SO3)2 . Above C 1 , surface tension reduces very slowly until the saturated concentration of C 2 is reached. Above C 2 , surface tension rapidly reduces until C M is attained, suggesting free n-s-n(SO 3 ) 2 micelles begin to form. In the region of C 1 -C M , the viscosity significantly increases. Above C M , surface tension is basically unchanged and these curves coincide with those of the single surfactant system. Moreover, the viscosity is almost constant. The SEM images indicate that fibrous aggregates are formed below C 1 , then transformed into multilayer fibrous aggregates above C 1 , and further into fiberbraided-structured and spider-web-structured aggregates above C M . The variation of viscosity is closely associated with the transformation of aggregates.

Research progress of viscoelastic surfactants for enhanced oil recovery

“…This makes the solution low in viscosity under high shear, easy to pump, and re-forms the network structure at a low flow rate deep in the formation and restores viscoelasticity (Chakraborty et al, 2011;Yu et al, 2014). Also, Gemini surfactants can achieve ultra-low interfacial tension at a lower concentration, which can effectively reduce oil-water interfacial tension, which makes Gemini surfactants have significant advantages in expanding swept volume and improving oil displacement efficiency (Jianxi, 1999;Li et al, 2016a;Wang et al, 2018;Zhao, 2014). From the structure and performance characteristics of Gemini surfactants, it is more in line with our requirements for viscoelastic surfactants for oil displacement.…”

Intermolecular Interactions in Polyelectrolyte and Surfactant Complexes in Solution

“…However the ratio shifts to the right with the increase in number of carbons in the hydrophobic block for the 6,12-ionene [137]. Wang et al showed that increasing the alkyl chain groups from 8 to 12 carbon for a Gemini surfactant significantly increased the viscosity, with a significant jump between the CAC and CMC, where the shorter alkyl chain Gemini surfactant steadily increased in viscosity with surfactant concentration during the entire regime [138].…”

Studying the Effect of Cross-Linking and Sulfonation on the Calcium-Binding Ability of Polystyrene Sulfonate in the Presence of Dodecyl Sulfate

“…For example, Molnar and Reiger studied the interaction between polyelectrolyte chains in the presence of calcium ions, Schweins et al studied the calcium ion-mediated conformational changes in polyelectrolyte chains, and Hsiao and Luijten studied the effect of calcium ion concentration on the collapse–expansion transition in polyelectrolytes . The interaction between like-charged polyelectrolytes and surfactants , has received lesser attention than that between oppositely charged or neutral polyelectrolytes and surfactants. − In our previous work, we discussed the possibility of achieving the desired response of PSS-Ca binding to the presence of the anionic surfactant dodecyl sulfate (DS). Additionally, we also investigated the effect of tacticity and the degree of sulfonation on the above response .…”