Abstract
The behavior and the mechanism of rheopexy are not well understood. We found that the suspensions. of spherical particles, such as ZnO and TiO2, show the rheopexy, and that it depends on the concentration of dispersing agent (NaPO3)6. The mechanism of the rheopexy and the rheopexy structure may be related to the colloid stability. ζ potential is measured as a parameter of colloid stability.
It can be assumed that there are two sorts of aggregation; one is the aggregation corresponding to the second minimum of the potential energy curve for the interaction of two charged particles and the other to the primary minimum. The mechanism of the rheopexy may be attributed to the solidification process in which the particles pass from the secondary to the primary minimum under the gentle shear, resulting in remarkable increase of apparent viscosity.
