Thermodynamic Aspects of Micelle Formation of Ionic Surfactant–Polymer Interactions

The thermodynamics of micellar aggregation involving ionic surfactants–sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (SDBS)–in the presence of guar gum (a natural polymer) and partially hydrolyzed polyacrylamide (PHPAM) have been systematically investigated using tensiometric and conductometric techniques. Critical micellar concentration (CMC) values for SDS and SDBS were accurately determined and the influence of polymer addition on these values was evaluated. Thermodynamic parameters, including the standard Gibb’s free energy (ΔGºm), enthalpy (ΔHºm) and entropy (ΔSºm) changes of micellization, were calculated to elucidate the nature of the micellization process. The results provide significant insights into the physico-chemical interactions at the surfactant-polymer interface, offering potential implications for various industrial and environmental applications.