DEAGGLOMERATION AND DISPERSION OF BARIUM-TITANATE AND ALUMINA POWDERSIN AN ORGANIC MEDIUM

The dispersion of noncolloidal barium titanate and alpha-alumina powde rs in an azeotropic ethanol/butanone mixture, using an amphiphilic est er phosphate as dispersant, has been investigated by a variety of tech niques, We show that residual water plays an important role in the dis persant adsorption process and in the dispersion mechanism, We also sh ow that the dispersion stability (sedimentation) and its theology are well correlated to each other and to the amount of adsorbed dispersant , and can be rationalized in terms of an effective volume fraction whi ch takes into account the envelope volume of the agglomerates. (C) 199 5 Academic Press, Inc.