Further Comments on Contact Angle Measurements on Polymer Solids

Abstract

In recent years much emphasis has been placed on the importance of specific interactions in determining a wide range of polymer properties. Following the work of Fowkes and coworkers,^1,2 all non-dispersion force interactions falling into the “specific” category may be considered to arise from acid/base interactions. This places heavy emphasis on methods for determining suitable acid/base parameters for polymers, with inverse gas chromatography (IGC) as a convenient choice. The IGC approach employed by one of us³ uses Gutmann's theory⁴ of (Lewis) acids and bases, and determines polymer interaction properties by placing these in contact with vapors of selected fluids for which acidlbase indexes, AN and DN, are available. Retention volume data for interacting vapor/polymer combinations are compared with the retention volumes of dispersion-force probes (e.g., n-alkanes), leading to the identification of AN and DN parameters for the polymer.³