Structural features and surfactant properties of core–shell type micellar aggregates formed by gemini piperidinium surfactants

Abstract

Abstract Aqueous micellar solution of piperidinium gemini surfactants was investigated by small angle X-ray scattering (SAXS) and the real space structural information of the micelles was deduced by indirect Fourier transformation (IFT) method. The maximum dimension of the micelles and their shape were determined by evaluating the pair distance distribution function (PDDF) and the electron density profile of the aqueous surfactant solution. These gemini surfactants formed core–shell type micelles in the aqueous solution above their cmc values having ellipsoidal structure. The dilute aqueous solutions of these surfactants were further investigated to determine their surfactant properties by surface tension and conductivity method. The self-aggregation and thermodynamic properties as well as the shape, size and internal structure of the micelles formed by these surfactants were found to be dependent on the methylene spacer units and hydrophobic alkyl chain length of the gemini surfactants.