Surface and electrokinetic properties of Y-TZP suspensions stabilized by polyelectrolytes

Yttria-doped tetragonal zirconia (Y-TZP, 3 mol% Y2O3) aqueous suspensions with NH4PAA and NH4PMAA polyelectrolytes as dispersants were prepared by the ball mill method. Surface chemistry of Y-TZP particles in aqueous suspensions was evaluated via isothermal adsorption, FTIR spectrum and zeta potential analysis. It was found that there was an optimum amount of dispersants absorbed on Y-TZP particles, which changes their surface properties dramatically in the FTIR spectra. Coated with dispersants, the electrokinetic properties of Y-TZP were obviously altered compared with the naked particles, the isoelectric points (IEP) were shifted to pH 2.1 and 2.3 by NH4PAA and NH4PMAA, respectively. The rheology of high solids loading Y-TZP suspensions demonstrate dramatic difference with low solids loading suspensions, 47 vol% solids loading suspension showed a viscosity about 600 mPa·s under 20 s−1 shear rate.