Kinetics of particle nucleation and growth in the emulsion polymerization of acrylic monomers

The rates of particle formation and growth during the earliest stages of the emulsion polymerization of several acrylic monomers have been studied as a function of surfactant concentration by means of the time-dependence of light scattering from the reaction mixtures. Investigated were methyl methacrylate, and methyl, ethyl, and butyl acrylates at concentrations of SDS surfactant from zero to several times the CMC. Under continuous photoinitiation, the Rayleigh scattering intensities rose rapidly with slopes that increased with decreasing SDS concentration. The more water-soluble the monomer, the more slowly was the rate of increase in scattering intensity.