INHOMOGENEITY OF SOLUTE DISTRIBUTION IN IONIC SYSTEMS

By using video imagery and an image data analyser, the ordering phenomena of polymer latex particles in dilute suspensions have been studied. The micrographs clearly showed the existence of localised ordered structure coexisting with disordered particles, and furthermore, fairly long-lived void structures were noted. The lattice vibrations of the particles on two adjoining lattice planes were shown to be coupled. Lattice defects were also found and the lattice vibration of the particle around the defect was anisotropic. The growth of the localised structure was found to obey the Ostwald ripening mechanism. All these findings validate the existence of an interparticle long-range attraction in addition to the short-range repulsion.