Host-guest interactions: I-Volumes of surfactant-ligand-water ternary systems

Abstract

The density measurements of sodium dodecyl sulphate (SDS) and dodecyltrimethylammonium bromide (DTAB) in aqueous 18-crown-6-ether (CR) and <i>β</i>- cyclodextrin (CYC) of 0.0170 mol dm^-3 of each have been made. Densities of these surfactants have also been measured in CR +CYC+W ternary mixture consisting of 0.0170:0.0170 mole ratio between CR and CYC. From the density data, apparent molar volumes of SDS <i>(V_ф,</i>_SDS) and DTAB <i>(V_ф,</i>_DTAB) have been computed. From the variation of apparent molar volumes of both the surfactants, it has been found that the presence of CYC results in a considerable higher values of <i>V_ф.</i>_SDS and <i>V_ф,.DTAB</i> in comparison to their values in the presence of CR. Also, CYC has a predominant effect on the micellisation of both the surfactants when it is present along with that of CR in a same CR +CYC+W ternary mixture.