Abstract
In the dispersion of agglomerated oxide nanoparticles by a beads mill, a method for determining both dispersant and optimum bead size was investigated. Acidic and basic characteristics of nanoparticle surface was determined by non-aqueous titration and it was confirmed that stable dispersion was obtained for the combination of acidic nanoparticles-basic dispersant, or basic nanoparticles-acidic dispersant. The relationship between the optimum bead size and the breaking strength of agglomerated nanoparticles for each circumferential speed was estimated from the comparison between experimental results at different bead sizes, and the equation suggested by Tanaka. These estimations indicated that changing the bead size was more effective than changing circumferential speed, and small-sized beads were not necessary for a high breaking strength of the agglomeration.
