Abstract: The rheological behaviors of α-Al₂O₃-H₂O-PAA suspensions prepared by two-stage adsorption
(at two different pH values) were studied. The results show that the stability of the suspension with a final pH 6.5 is improved considerably if it experiences
an adsorption stage at pH above the iep of the alumina. The pH values of the first adsorption stage have a great impact on the stability of slurries. When the
pH value increases from 8.0 to 10.0, the viscosity of the slurry decreases and the stability is enhanced. But when the pH reaches 11.0, the viscosity
of the slurry increases and the stability declines. Increasing the time of the first adsorption stage is helpful to the stabilization of suspensions,
due to improved homogeneity of the distribution of PAA on the particle surfaces.

Key words: PAA, α-Al₂O₃, suspension, adsorption-route, rheology