Investigation of adhesive- pigment interactions in coating mixtures

Rheological evidence is presented which indicates that the major starch- pigment interaction is that of the starch acting as a dispersant. Possible mechanisms of starch functioning as a dispersant are discussed and a theory is proposed which explains the data included in this paper as well as some other recent data. Specific conclusions are that starch will disperse clay and calcium carbonate, with oxidized starch being the best dispersant. The latices tested created a flocculated condition with nondispersed clay and calcium carbonate but not titanium dioxide.