The Visco-Elastisity of Montmorillonite Paste

Abstract

The viscosity and the rigidity of stirred Ca-and Na-montmorillonite paste were measured using a forced oscillation rheometer. The results are summarized as follows:
(1) When the agitation ceased, the viscosity of Ca-and Na-montmonillonite decreased with time. The rigidity of Ca-montmovillonite also decreased. The rigidity of Na-montmorillonite decreased at low concentrations but increased at slightly high concentrations.
(2) The viscosity and rigidity of Ca-montmorillonite changed more quickly with decreasing oscillation frequency, whereas the same Na-montmorillonite properties didn't change more quickly and decreased.
(3) When the oscillation amplitude increased, the rigidity of Ca-montmorillonite increased while the viscosity and rigidity of Ca-montmorillonite decreased.
(4) The effect of concentration on the visco-elastic properties of Na-montmorillonite is greater than in the case of Ca-montmorillonite.
In the present paper, the effect of the non-agitated state, oscillation period, and amplitude on the visco-elastic properties of the clay-water system are considered in the light of the following twofactors:
(1) Dissipation (Disappearance) of the electric double-layer on the surface of the clay particles (by the external energy) and development of thc electric double-layer when the sample is at rest.
(2) Flocculation of the clay particles.