Temperature Effect on the Adsorption and Volumetric Properties of Aqueous Solutions of Kolliphor^®ELP

Abstract

Density, viscosity and surface tension of Kolliphor® ELP, the nonionic surfactant aqueous solutions were measured at temperature T = 293−318 K and at 5K interval. Steady-state fluorescence measurements have been also made using pyrene as a probe. On the basis of the obtained results, a number of thermodynamic, thermo-acoustic and anharmonic parameters of the studied surfactant have been evaluated and interpreted in terms of structural effects and solute−solvent interactions. The results suggest that the molecules of studied surfactant at concentrations higher than the critical micelle concentration act as structure makers of the water structure.

Keywords

• kolliphor^® elp
• volume expansivity
• thermo-acoustic parameters
• gruneisen parameter
• fractional free volume
• coiling and micropolarity index