Thermodynamic Properties of Gum Arabic and AcaiaPolyacantha Gum Solutions

Abstract

The thermodynamic properties of A. senegal gum, A. seyal gum (gum arabic) and A. polyacantha gum solutions were measured and calculated. The partial specific volume of gum, partial specific volume of the solvent (water) and the volume fractions were measured and calculated. The results show that the sequences of the specific volumes of the gums under studies are in the order of decreasing molecular weight of these gums. The results of density of solid gums indicate that A. seyal molecule is more compact than A. senegal gum molecule and A. polyacantha gum molecule. The chemical potentials have been calculated from osmotic measurement for different concentrations, and then the second virial coefficients, the free energy of mixing and the gums–water interaction parameter  χ were calculated. The obtained results indicate that A. polyacantha gum thermodynamically resembles A. senegal gum and they were interacting with water more than A. seyal gum.