ELECTROKINETIC SONIC AMPLITUDE OF COLLOIDAL POLY(METHYL METHACRYLATE) AND LUDOX(R)-TM

The electrokinetic sonic amplitude (ESA) of aqueous suspensions of a poly(methyl methacrylate) latex and of the colloidal silica, Ludox(R)-TM, is reported as a function of particle volume fraction. The use of these readily obtainable materials as standards for the calibration of ESA apparatus is described. Such calibration procedures facilitate the conversion of ESA measurements to electrophoretic mobilities. We report results obtained, in parallel experiments, with two separate instrumentation systems in two of our respective laboratories. The precision of these techniques appears competitive with other classical electrophoretic methods.