Inverse gas chromatography, surface properties, and interactions among components of paint formulations

Inverse gas chromatography (IGC) was applied to the surface characterizatio n of polymers and pigments used in the formulation of protective coatings. IGC measurements over a significant temperature range provided surface ener gy and acid-base interaction parameters for these materials. Two sets of IG C data were obtained: (1) the quantity of vapor used to probe solid surface s was extremely small, with results describing the average properties of su rface sites. a comparison of the two sets gave information on the heterogen eity of sites on the polymer and pigment surfaces. Heterogeneity parameters were defined for sites interacting through dispersion forces as well as fo r those able to interact as acids and bases. The present work reinforces th e usefulness of characterizations by IGC by showing that the stability of p igments dispersed in the polymer vehicles was a function of the acid-base i nteraction between polymer-pigment pairs.