Stability of Aqueous α‐Al2O3 Suspensions with Poly(methacrylic acid) Polyelectrolyte

Stability of aqueous α‐Al 2 O 3 suspensions with Na + salt of poly(methacrylic acid) (PMAA‐Na) polyelectrolyte was studied as a function of pH. At a given pH, the transition from the flocculated to the dispersed state corresponded to the adsorption saturation limit of the powders by the PMAA. As the pH was decreased, the adsorption saturation limit increased until insolubility and charge neutralization of the PMAA was approached. The critical amount of PMAA required to achieve stability is outlined in a stability map.