STABILIZATION OF AQUEOUS CLAY SUSPENSIONS WITH AOT VESICULAR SOLUTIONS

Greatly extended stability of clay aqueous suspensions of particles of size about 10-100 nm is achieved by the incorporation of Aerosol OT ( AOT) vesicular solutions. Direct images of the interactions between cl ay particles with AOT vesicles and liposomes in aqueous suspensions, w ith and without added NaCl, have been obtained for the first time by a rtifact free (no drying and no staining) cryogenic transmission electr on microscopy (cryo-TEM). Combined centrifugation and cryo-TEM results indicate that the heightened stability of the clay-ACT suspension is due mainly to strictly limited mobility and separation of clay particl e aggregates in the presence of large multi-bilayers, and to a lesser extent by the encapsulation of clay particles. Greatly reduced rigidit y of bilayers and shrinking of vesicles, with the added NaCl, lead to a lowered effect of stabilization with AOT vesicular solutions.