Effect of sucrose on rheological properties of aqueous zirconia suspensions with polyacrylate

The role of pH, additive concentration, aging time and solids loading in determining the rheological properties of aqueous zirconia suspensions, which contained polyelectrolyte and sucrose molecules, was investigated. It was found that at alkaline pH, the appropriate sucrose addition (4 wt.%) enhanced the stability of zirconia suspensions with polyacrylate, and the amount of polymer required to obtain the maximum fluidity decreased as sucrose was added. However, the positive effect of sucrose on stability cannot maintain at the higher solids loading (40 vol.%) because of the bridging attraction between the overlapping adlayers. On the other hand, the effectiveness of sucrose would be greatly weakened by hydrolyzation in acidic media as well as biodegradation with aging time.

At alkaline pH, the simultaneous addition of sucrose and PANH4 in suspensions could result in a much higher stability than the only polymer contained slurries, suggesting the electrosteric repulsion is enhanced due to the presence of sucrose molecules in association with the polyacrylate adsorbed on particle surfaces.Figure optionsDownload as PowerPoint slide