Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

A new hypothesis is suggested for the evaluation of the components (γ^d and γ^ab) and the elements (γ^a and γ^b) of the surface free energy. The respective equations are introduced for the interactions at interfaces between a non-polar acid and non-polar base, a polar phase and non-polar acid or base, and two polar phases. The dispersion component, γ^d, equals the total surface free energy of non-polar phases. However, they can interact at the interface as an acid or a base through their single permanent elements γ^a or γ^b, respectively. Otherwise, induced elements γ^ia and γ^ib can also be effective. The surface free energy of polar phases is additively composed of the dispersion, γ^d, and acid-base components, γ^ab = 2(γ^aγ^b)^1/2. The proposed equation are verified using the known values of the surface and interfacial free energies for the liquid-liquid systems and they are applied to the solid-liquid interfaces. The values of the elements are determined for water, γ_w^a = 67.7 and γ_w^b = 10.6 mJ/m², and for other liquids, such as glycerol, formamide, mercury, benzene, diethyl ether and trichloromethane.