The colloidal stability of barium titanate (BT) aqueous suspensions with poly(acrylamide/4-carboxyl-amino-4-oxo-2-butenate) (PAAM/COB) at pH 7, 9, and 12 has been investigated by means of potential, adsorption, sedimentation, and particle size measurements. The isoelectric point of BT powder is at pH 4.6 and the value of potential decreases as the pH of suspensions increases. The adsorption of PAAM/COB onto BT particles follows the Langmuir adsorption isotherm. The saturated amount of adsorbed polymer decreases with increasing pH. In general, BT particles in basic solutions with PAAM/COB are more stabilized, and less agglomerated than those without any dispersant present. As pH is increased, the resulting potential becomes more negative, although lower polymer concentration is required for monolayer coverage of particle surface. Consequently, the resulting suspensions become more stabilized, and contain powder with smaller particle size. (c) 2006 Wiley Periodicals, Inc.