Effects of particle concentration and additive amount of dispersant on adsorption behavior of dispersant to alumina particles

Abstract

We investigated the effects of particle concentration and an additive amount of a dispersant on the adsorption behavior of dispersant. Ammonium polycarboxylate, one of the typical polyelectrolyte was used as a dispersant in this study. Alumina slurries were prepared by changing the concentrations of both the particle and dispersant and kept in a test tube for at least 2 d. After that, the adsorbed dispersant amount was calculated from the residual dispersant concentration measured by a total organic carbon analyzer. It was found that the adsorbed dispersant amount strongly depends on the additive dispersant amount on the basis of the unit mass of particles in the slurry regardless of the particle concentration. It was also shown that polycarboxylic acid strongly absorbs onto an alumina surface and can not be desorbed by dilution, suggesting that its adsorption behavior differs from physical adsorption.

Fabrication of SiCf/SiC composites by alternating current electrophoretic deposition (AC–EPD) and hot pressing

“…Therefore, ammonium polycarboxylate was added, which is known as an effective aqueous dispersant for SiC. [40][41][42] Fig. 3(a) shows the behavior of the zeta potential for SiC as a function of the pH and dispersant concentrations.…”

Aqueous and Nonaqueous Colloidal Processing of Difficult‐to‐Densify Ceramics: Suspension Rheology and Particle Packing

“…The optimum concentration of the dispersants which corresponded to the lowest viscosity was found to be 0.1 wt% Darvan‐PAA, 0.1 wt% Darvan‐PMAA and 0.05 wt% Dolapix‐citric acid. At the optimum concentration, it is assumed that most of the dispersant is fully adsorbed onto the powder surface and there is a little excess dispersant in solution …”

Effects of sintering additives on dispersion properties of Al2O3 slurry containing polyacrylic acid dispersant

“…Additionally, the amount of added PAA was higher in comparison with AES12. 20 Many researchers have attributed this specific adsorption isotherm to the effects of multivalent ions on the adsorption state. The multivalent ion interactions can promote association of the carboxylate group of PAA via multivalent ion bridging 7,8,11 and charge neutralization of the carboxylate group.…”