Colloidal stability - investigations by single-particle scattering photometer

The single-particle lightscattering technique proves to be suitable for determination of particle size distribution with very high resolution. In particular, first steps of a coagulation process call be determined very sensitively. Rapid coagulation led to good correspondence with theory in the case of spherical oxide particles. For quasi-spherical particles (with edges and corners) satisfactory experimental results have been obtained by extension of the theory. In all the experiments a decay of aggregates could be proved. However, theoretical determined velocity constants at slow coagulation could not be confirmed by experiments. Coagulation takes place in a wider electrolyte region as expected.