Empirical and Theoretical Treatments

Various means have been developed for prediciting or calculating a yab or a work of adhesion. Two empirical ones are the following. First, an early relationship is that known as Antonow s rule [13], 

This rule is approximately obeyed by a large number of systems, although there are many exceptions see Refs. 15-18. The rule can be understood in terms of a simple physical picture. There should be an adsorbed film of substance B on the surface of liquid A. If we regard this film to be thick enough to have the properties of bulk liquid B, then 7a(B) is effectively the interfacial tension of a duplex surface and should be equal to 7ab + VB(A)- Equation IV-6 then follows. See also Refs. 14 and 18. 

The different kinds of intermolecular forces (dispersion, dipole-dipole, hydrogen bonding, etc. see Section VI-1) may not equally contribute to A-A, B-B, and A-B 

IV-9 would use the surface tensions that liquids A and B would have if their inter-molecular potentials contained only the same kinds of interactions as those involved between A and B (see Refs. 20, 22-24). For the hydrocarbon-water system, Fowkes [20] assumed that Uh arose solely from dispersion interactions leaving 

When both liquids are polar, Fowkes [26] has written 

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