Monitoring of Aggregation Kinetics of Colloidal Systems by Light Scattering Methods

An original methodology is discussed for studying the aggregation kinetics of colloidal solutions. The methodology is based on the joint application of dynamic and static light scattering methods. The proposed methodology is theoretically justified by the concept of fractal dimension and scaling. Its experimental implementation is carried out using the example of colloidal gold solution aggregation initiated by a change in the ionic strength of the solution. The fractal dimension of Au clusters is determined from the angular and kinetic dependences of static light scattering. The hydrodynamic radii of the clusters are determined by the dynamic light scattering method. Based on the experimental results and a constructed model dependence of light scattering intensity on the sizes of clusters, a kinetic dependence is plotted for the concentration of Au clusters and the rate of their aggregation is estimated. The proposed method can be used to study the aggregation kinetics of fractal clusters in various colloidal systems.