  Self-assembly structures of gemini surfactants are characterized, among
others, for their low CMC. This characteristic could be due to great
hydrophobic parts in their molecular structures. That availability could imply
great stability of self-assembly structures or monolayers absorbed in an
interface. The micellization behavior of two cationic gemini surfactants,
{\alpha},{\omega}-bis(S-alkyl dimethylammonium) alkane bromides, were studied
by a modelization of dynamic surface tension (DST) experimental data and
isothermal titration calorimetry (ITC) measurements. The adsorption data at the
air/water interface was taken through the analysis of the profile changes of a
pendant drop. The thermodynamic characterization of the micellization process
of the gemini surfactants was carried out using ITC. A model based on the
Frumkin adsorption isotherm and the Ward-Tordai diffusion equation was
developed to obtain the characteristic parameters of the adsorption without the
need of using the Gibbs adsorption equation. Positive values of lateral
interaction show good stability of the adsorbed monolayer. The ITC data were
analyzed following a novel protocol based on the identification of the
different energetic contributions and regimens observed in the titration
enthalpograms from demicellization processes. The presence of exothermic peaks
would explain the low values of CMC.
