Surface Characterization of NH4PAA-Stabilized Zirconia Suspensions

Ammonium polyacrylate (NH4PAA) stabilized yttria-doped (3 mol%) tetragonal zirconia (Y-TZP) aqueous suspensions were prepared. Surface chemistry of the suspension was investigated by a variety of techniques. Isotherm adsorption of dispersants on ZrO2 particles demonstrated an optimum coverage of 0.25 mg/g at pH 10. The isoelectric point (IEP) of ZrO2 suspensions was shifted to low pH regions with the presence of NH4PAA. Scanning auger microscopy (SAM) and FTIR and UV spectrophotometry were employed to determine the surface properties of ZrO2 suspensions, which confirmed that the surface Zr-O bonds were affected by the adsorbed polymers. Atomic force microscopy (AFM) analysis indicated that the interactions between particles were evidently influenced by polymer dispersants. Copyright 1999 Academic Press.