Mixtures of carboxymethyl cellulose (carboxyMC) and cethyltrimethyl ammonium bromide (CTAB) were investigated using surface tension, specific conductivity and density measurements. The parameters of the surfactant to polymer association processes such as the critical aggregation concentration (cac) and the polymer saturation point (psp) were determined from the plots of surface tension, specific conductivity and density versus surfactant concentration. The thermodynamic parameters of polymer-surfactant interaction were calculated at different temperatures. The results showed that the standard Gibbs free energy ðDG 0 psi Þ, the enthalpy ðDH 0 psi Þ and the entropy ðDS 0 psi Þ of the aggregation process were found negative in all cases.