Dispersions of pigments containing different ions have been studied in waterborne latices in which the polymer contains ionizable functional groups. Each system has been tested for related adhesion properties when coated on metallic substrates. Vibrational spectroscopy has been used to analyze the polymer structural changes due to the presence of the different ions in these systems. This information has been extremely useful in elucidation of the conformational changes of the polymer associated with the ion-polymer interactions.
The polymer structural changes detected by infrared analysis have also been correlated with the overall adhesion and cohesion strength in the system. These results could have a significant bearing on the mechanism of the pigment-polymer association in waterborne coatings and adhesives. The results are discussed in light of the polymer charge density and two-phase condensation model for polyelectrolytes.
Specific factors, originating in both the public and private sectors, have created the need for replacement of some solventborne adhesive and coating systems with safer aqueous products.