Good-Girifalco interaction parameter

Many different measures may be used to specify this fundamental adhesion. It may be expressed in terms of forces or in terms of energies. Again, depending on the context, these may be forces or energies of attachment or else of detachment. Sometimes values of fundamental adhesion can be calculated from a theoretical model (see Electrostatic theory of adhesion, Good-Girifalco interaction parameter) occasionally, they may be deduced from experimental measurement (see Adhesion-fundamental and practical) for many practical adhesive bonds, they are not available by either route. 

Further insight comes from consideration of the Good-Girifalco interaction parameter theory, which gives the following equation. 

The second problem involves interpretation of the interfacial tension ysL (there is no difficulty concerning = y since the liquid must coexist with its vapour). The interfacial tension must be lower than the snm of the two individual surface tensions (otherwise the interface would not form) by an amount related to them (it is a consequence of the same forces that give rise to the individual surface tension). Good and Girifalco expressed this (see Good-Girifalco interaction parameter) as... 

The theory of the Good-Girifalco interaction parameter can be developed to give some support for this relationship. This was not accepted by Fowkes, who argued that the principal non-dispersion interactions are Acid-base interactions, for which a geometric mean relationship does not apply. 

The concept of surface energy components provides one route to interfacial tensions and solid surface energies and others include the Good-Girifalco interaction parameter and Acid-base interactions. 

Good-Girifalco interaction parameter D E PACKHAM Definition of (p evaluation for dispersion force interface interfacial tension solid surface energies... 

Good-Girifalco interaction parameter mechanical loss function... 

From Eq. (84), which describes the components of the Good and Girifalco interaction parameter, g, it can be seen that the components of the forces which interact across interfaces are considered to be additive, as shown in Eq. (85),... 

The Good-Girifalco theory [77-82] was originally formulated to make an attempt to correlate the solid-liquid interfacial tension to the solid surface energy and the liquid surface tension through an interaction parameter, basic formulation of the theory is ... 

In a similar manner, an expression for the interfacial tension, Yf can be written using the geometric mean definition for work of adhesion, Wa (see Figure 8), and the Girifalco-Good interaction parameter (17-18), as. 

A final quasi-thermodynamic approach to molecular structure effects has been proposed by Good et al. (17-18) which relates molar volumes and the Girifalco-Good interaction parameter, as... 

Interaction Parameters. A valuable approach to the problem of interpreting contact angle data has been initiated by Good and Girifalco [38]. As noted above, this approach is based on an expression relating the interfacial tension for two immiscible phases to the surface tensions of the individual phases [36,37]. If one of the phases is a solid, this expression is... 

The factor denoted in these equations by Z 3 is called here the interaction parameter. (The symbol was employed for this quantity by Good and Girifalco.)... 

Considerations arising from statistical mechanics and the theory of intermolecular forces can be used to estimate values of the interaction parameter. The pertinent theory has been discussed by Girifalco and Good [36] and independently by Moelwyn-Hughes [54]. However, this approach can be justified only for phases composed of spherical molecules which do not differ greatly in size. The actual importance and usefulness of the interaction parameter are consequently for purposes of correlating existing experimental data. 

Good and Girifalco defined an interaction parameter (cp) from molecular interaction theory, which is given in terms of and Wc by... 

Good-Girifalco-Fowkes (GGF) equation Using Xsi = Xsv + yiv - 2(ysvyiv) in Young s equation leads to 1+COS0 Xggf obtained from a plot COS0 versus 4> is solid-liquid interaction parameter 0 = 1 if the interactions are purely dispersive. Based on Berthelot relation for atuactive constants valid only when the solid-liquid interactions are dominantly dispersive. [77-82]... 

Girifalco and Good [46] assumed the interaction between a solid and a liquid could be quantified by an interaction parameter ) times the geometric mean of the surface tension of the solid and the liquid resulting in Equation (3). 

A significant advance was made in the understanding of interfacial energies when Good and Girifalco defined their interaction parameter f in terms of the work of adhesion... 

In the equation for the work of adhesion (Eq. 36), the term 712 describes the interaction of one surface with another. A substantial amount of work has gone into methods for predicting 712. One of the more quoted methods is that of Good and Girifalco. " The basis of the Good and Girifalco calculation is to define a pseudo-thermodynamic parameter, 4>g, known as the interaction parameter, as shown in Eq. (78),... 

The interfacial tensions can, then, be related to the pure-component surface tensions by expressing ITa in terms of the Good-Girifalco [180, 189-192] interaction parameter 4>gg-... 

When polar contributions are neglected, (27) reduces to the Fowkes equation [196]. In terms of the Good-Girifalco equation (21), the interaction parameter is given by ... 

The dimensionless interaction parameter (p expresses implicitly the effect of all interactions in the given interphase on the interfacial tension 7sl- the framework of the Girifalco-Good concept, Eq. 6.20a represents the form proposed for the equation of state 6.13. Hence, Eq. 6.20a has to refer to all phases involved and should be written more precisely as... 

This equation is somewhat similar to that of Girifalco and Good [11], except that these authors used a parameter in the last term (-2 NTy7 ) and did not distinguish between surface tensions resulting from various types of intermolecular forces. The values of were about 0.5 for water-hydrocarbon interfaces. The Berthelot relation in Equation 1 is not exact, as can be shown by the London pair potentials, but is seldom in error by more than 2%, and the geometric mean is applied to only the interacting contributions to the surface tension. 

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