Thermodynamic investigation of the systems poly(ethylene glycol) + sodium pentane-1-sulfonate + water and poly(vinyl pyrrolidone) + sodium pentane-1-sulfonate + water

Volumetric Analysis of Structural Changes of Cationic Micelles in the Presence of Quaternary Ammonium Salts

“…However, the negative values tend to increase with [DTAB]. This is likely due to the self-association of surfactant which results in the release of some water molecules from the counterion upon the binding to the micelles making the system more compressible . Also the rise in κ S,φ values with increment in temperature as well as alkyl chain length of bromide salts may be due to the loss of hydrophobic hydration, showing the importance of solute–solvent interactions in the present system.…”

A comparison study between sodium dodecyl sulfate and sodium dodecyl sulfonate with respect to the thermodynamic properties, micellization, and interaction with poly(ethylene glycol) in aqueous solutions

“…In continuation of our previous works on the thermodynamic properties of aqueous polymer-surfactant solutions [6,7], and in order to study the effect of PEG and temperature on the apparent molar volume and isentropic compressibility as well as the conductivity behavior of the monomer and micellar state of C 12 H 25 SO 4 Na and C 12 H 25 SO 3 Na, and therefore make a thorough analysis of the differences between C 12 H 25 SO 4 Na and C 12 H 25 SO 3 Na with respect to the their thermodynamic properties, micellization, and interaction with PEG in aqueous solutions, the apparent molar volume and isentropic compressibility of C 12 H 25 SO 4 Na and C 12 H 25 SO 3 Na in water and in aqueous solutions of PEG were determined at different temperatures from the accurate measurements of density and ultrasonic velocity. Furthermore, the electrical conductivity of these solutions was determined at different temperatures below and above the micellar composition range.…”

Volumetric and Compressibility Studies of Ionic Surfactants in Aqueous Solutions of Tetraalkylammonium Cation-Based Ionic Liquids

“…A curious inspection of Tables S4 and S5 reveals that the values of apparent molar volume are positive for both the surfactants in aqueous solutions, demonstrating that the ionic interactions are operative in the micellization process. In aqueous solutions of ILs, the values of V ϕ are found to be positive for DTAB . However, in the case of SDS, the values are negative, but of smaller magnitude at 293.15 K at low surfactant concentrations in the case of aqueous solutions of Bu 4 NBr, Pr 4 NNO 3 , Bu 4 NOAc, and Pen 4 NOAc, signifying the superiority of hydrophobic interactions over the ionic interactions at this temperature.…”

“…In aqueous solutions of ILs, the values of V ϕ are found to be positive for DTAB. 36 However, in the case of SDS, the values are negative, but of smaller magnitude at 293.15 K at low surfactant concentrations in the case of aqueous solutions of Bu 4 NBr, Pr 4 NNO 3 , Bu 4 NOAc, and Pen 4 NOAc, signifying the superiority of hydrophobic interactions over the ionic interactions at this temperature. These negative values tend to increase and become positive with [SDS] and temperature, suggesting that the ion−ion interactions seem to dominate at higher temperatures.…”

“…However, the negative values tend to increase with [DTAB]. This is likely to be due to the self-association of the surfactant which results in the release of some water molecules from the counterion upon the binding to the micelles making the system more compressible . Also, the rise in κ S,ϕ values with an increment in temperature and the alkyl chain length of IL may be due to the loss of hydrophobic hydration, showing the importance of solute–solvent interactions in the surfactant-IL system.…”