Good-Fowkes model

Fig. IV-2. The Good-Fowkes model for calculating interfacial tension. (From Ref. 20.)...

Figure 2. Good-Fowkes model jor interfacial interactions...

B. Semiempirical Models The Girifalco-Good-Fowkes-Young Equation... 

The same logic that we used to obtain the Girifalco-Good-Fowkes equation in Section 6.10 suggests that the dispersion component of the surface tension yd may be better to use than 7 itself when additional interactions besides London forces operate between the molecules. Also, it has been suggested that intermolecular spacing should be explicitly considered within the bulk phases, especially when the interaction at d = d0 is evaluated. The Hamaker approach, after all, treats matter as continuous, and at small separations the graininess of matter can make a difference in the attraction. The latter has been incorporated into one model, which results in the expression... 

In Table 5.4, values for the interfacial tensions of various water/liquid interfaces, as calculated by the models of Fowkes and Girifalco and Good, are compared with measured values. It is clear that Fowkes model gives good results for aliphatic hydrocarbons that interact with water by dispersion forces only. As soon as polar interactions (tt electrons, dipoles, hydrogen bonding, etc.) play a role as well, strongly... 

The matter of rfi is of some importance to the estimation of solid interfacial tensions and has yet to be resolved. On one hand, it has been shown that the Giralfco and Good model carries the implication of rr being generally significant [10], and on the other hand, both Good [193] and Fowkes [145] propose equations that predict... 

The model of Girifalco, Good, and Fowkes has been extended to other interactions. For example, if we assume that the surface energies are the sum of van der Waals (dispersive) and polar interactions, one often uses the equation [272]... 

Interfacial Tensions (mj m" ) of Water (a)/ Liquid O) Interfaces Calculated Using the Models of Fowkes and Girifalco and Good, and Derived from Direct Measurement ... 

Compare the Fowkes, Owens-Wendt and van Oss-Good theories for these non-aqueous liquid-liquid interfacial tensions. Which model performs best ... 

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