Determination of rate constants for the rapid coagulation of polystyrene microspheres using photon correlation spectroscopy

Abstract

The rapid aggregation of polystyrene microspheres was investigated using a photon correlation technique. An innovative method of obtaining the rate constant from the exponential autocorrelation function has been developed. The aggregation obeys Smoluchowski kinetics very well up to two half-lives and satisfactorily up to four half-lives. A rate constant of 2.0 × 10^–12 cm³ s^–1 was deduced from these experiments. The technique provides a quick and relatively routine evaluation of the rate constant for the aggregation of monodisperse spherical suspensions.