Interfacial and Solution Properties of Tetraalkylammonium Bromides and their Sodium Dodecyl Sulfate Interacted Products:  A Detailed Physicochemical Study

Abstract

The adsorption and solution behaviors of symmetrical tetramethyl-, tetraethyl-, tetrapropyl-, and tetrabutylammonium bromides (TMAB, TEAB, TPAB, and TBAB, respectively) were studied at the air/water interface and in the bulk aqueous environments. Their salts were prepared by reacting tetraalkylammonium bromide (TAAB) with sodium dodecyl sulfate (SDS) in a solution from which the products of the higher two homologues (tetrapropylammonium dodecyl sulfate (TPADS) and tetrabutylammonium dodecyl sulfate (TBADS)) could only be isolated as solids and for which detailed characterization has been performed. The interfacial behaviors of 1:1 molar mixtures of TAAB and SDS and the prepared TPADS and TBADS were examined. Micellization of the 1:1 mixtures along with the isolated species were studied in the presence and absence of NaBr salt. The energetics of the micellization process and the counterion binding of the micelles were evaluated. The interaction of the TAABs with SDS micelles was examined, and the results were evaluated in terms of single- and two-site binding interaction models. Of the formed tetraalkylammonium dodecyl sulfates (TAADSs), only TBADS evidenced clouding, which was investigated in detail along with 1:1 molar mixtures of TBAB and SDS in aqueous solution in the presence of additives such as NaBr, SDS, and TBAB. The solution behaviors of the TAADS and the clouding of TBADS have been rationalized in terms of a mixed micellar model.

Amphiphile self-aggregation: An attempt to reconcile the agreement–disagreement between the enthalpies of micellization determined by the van’t Hoff and Calorimetry methods

“…It is a dependable physical method to study the process of micellization [42]. There are numerous available literature that have used ITC for amphiphile aggregation [1][2][3][4][5]23,[31][32][33]35,[41][42][43][44][45][46][47], thermodynamics of bilayers-to-micelle transition [48,49], amphiphile interaction with polymers and macromolecules [50][51][52][53][54][55][56][57], characterization of protein solution [58], binding of small molecules with biopolymers [59][60][61], interaction of microemulsion with vesicles [62], determination of second virial coefficient of ionic liquid microemulsion [63], kinetics of reaction [64], etc. We have also used the method and have shown a general way of data treatment for microheterogeneous systems like micelles [65] and microemulsions [66].…”

Development of supramolecular solvent based microextraction prior to high performance liquid chromatography for simultaneous determination of phenols in environmental water

“…To promote the phase separation, the addition of a cosurfactant with a small head group, an amphiphile counterion, was studied to replace the use of concentrate acid in the conventional method. [28][29][30] In this work, SDS was used as dodecyl sulfate anionic micelle, thus the oppositely charge, TBABr, was investigated as the amphiphilic counter-ion to reduce ionic head group repulsion. 29 An inuence of TBABr (CMC ¼ 588 mmol L À1 ) was investigated in the concentration range of 50-125 mmol L À1 .…”

Nanoporous Organosilicate Films Prepared in Acidic Conditions Using Tetraalkylammonium Bromide Porogens

“…The selfassociation properties of TPA molecules at high concentration in solution previously have been demonstrated. [31] Another possibility is that large micelles may have formed in the as-deposited films through nucleation and growth during the heating operation. [7] Whatever the mechanism of formation, these 17 nm pores were no longer obtained when the mixture was aged for 1-2 months before spin-coating.…”