Other Physicochemical Influences in Adsorbed Film Behavior

Other Physicochemical Influences in Adsorbed Film Behavior 

Bailey and Kay [38] measured the work required to cleave mica under various circumstances. Some of their data are shown in Table 10-10. The influence of exposure to air and moisture is clearly evident in the values seen there for interfacial energy the surface energy computed from coulombic interactions vacuo between freshly separated surfaces 

TABLE 10-10. OBSERVED INTERFACIAL ENERGY OF CLEAVED MICA IN VARIOUS ENVIRONMENTS 

J/m for the separation of two sheets of mica, each coated with a monolayer of lauric acid by retraction from n-decane solution and resealed by contact and then re-separated. This value should be compared with the 0.024 J/m reported by Zisman [42] for monolayers whose exposed surfaces are comprised of methyl groups. 

Israelachvili and Tabor [43] investigated the van der Waals dispersion forces for mica surfaces exposed to the ambient atmosphere and thus carrying the ordinary contamination of adsorbed air and water vapor. They also investigated the van der Waals forces for mica surfaces covered 

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