Three types of fatty acids - namely, stearic acid, oleic acid, and 12-hydroxystearic acid - were used as dispersants for stabilization of highly concentrated zirconia-wax suspensions. Rheological properties such as viscosity and yield stress of the suspensions were determined over a temperature range of 65°-85°C. Experimental results indicated that better suspension stabilization was achieved when the 12-hydroxystearic acid was used. Adsorption behavior revealed a greater affinity at the solid/liquid interface that occurred for the 12-hydroxystearic acid than for stearic acid or oleic acid. This observation suggests that the adsorption of 12-hydroxystearic acid may lead to a better packing (or surface concentration) of the acid molecules onto the solid surface than others and also results in a better suspension fluidity and processability. Attractive interparticle interaction was estimated quantitatively by using the Void model and resulting analysis showed a linear correlation between the yield stress and the attractive potential for the suspensions.
|Number of pages||7|
|Journal||Journal of the American Ceramic Society|
|State||Published - 1 Dec 1999|