The theological properties of titanium dioxide dispersed in water are measu
red over a wide range of powder concentrations, temperatures, and pH values
. The value of intrinsic viscosity of titanium dioxide measured with an Ubb
elohde capillary viscometer is 3.55, which is useful for determining the sh
ape and aggregation property of the particles. The yield stress and steady
shear viscosity of titanium dioxide with broad and narrow particle size dis
tributions were measured over a wide range of solid volume fractions on a B
rabender rheometer. It is observed that the theological properties of the s
uspensions are quite different due to the difference in particle size distr
ibutions. Quemada, Casson, and Zhou's models were used to fit the experimen
tal data and useful parameters were obtained. Calculated data are also in g
ood agreement with the experimental data. As expected, the shear viscosity
and yield stress decrease with increasing temperature. But when the tempera
ture is around 50 degreesC, yield stress increases with increasing temperat
ure while shear viscosity exhibits a complex behavior. The phenomena are ve
ry interesting and special. The Peclet number was used to analyze the shear
thickening behavior. Models were also used to describe the shear viscosity
under different temperatures and the master plots of the reduced variables
eta/eta (infinity), vs t(c)(gamma) over dot at different temperatures are
superimposed, which means the agreement is fair and the models are suitable
to describe the theological properties of titanium dioxide suspensions. pH
effects were investigated on a Rheometrics RFS-II rheometer and it was fou
nd that pH can change the surface charge of the particles, which also affec
ts the theological behavior. The pH at which maximum shear viscosity and yi
eld stress occur is in concordance with the isoelectric point, (C) 2001 Aca
demic Press.