What do we believe about the van Oss-Good and Neumann theories

5 What do we believe about the van Oss-Good and Neumann theories  

The discussion of the van Oss-Good and Neumann theories is compheated by many factors, e.g. the validity range of the Young equation, the role of spreading pressure, the accuracy of experimental contact angle data and others. 

Despite the criticism, the Neumann method is useful in many practical applications. Table 15.5 and other similar results from the literature (see references in the table) provide Neumann values for several polymers obtained from the method. Clearly, the Neumann method has been applied to a wide range of polymers and other solids (over 50 different solid surfaces) with surface tensions from around or below 10 mN m up to more than 40 mN m This list includes thus hydrophobic, non-polar and polar polymers. This wide applicability is a positive characteristic of the method. 

Overall, we beheve that the van Oss-Good method is, despite its well-documented limitations, the best among the two recent theories and moreover it can be used for surface analysis as well. The Neumann 

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