Characterization of Miniemulsion Polymerization by Small-Angle Neutron Scattering

Emulsion polymerization is one of the major techniques for the manufacture of adhesives, coatings, thermoplastics and elastomers. In miniemulsion polymerization, relatively stable oil droplets within a size range of 500 to 5000 Å are prepared by emulsifying a monomer in a medium, generally water, with the aid of a surfactant and a hydrophobic compound. Droplet size and size distribution are by far the most important parameters of miniemulsion because they affect directly both the miniemulsion stability and droplet nucleation. Therefore, the understanding of the mechanism ruling miniemulsion polymerization strongly depends on an accurate determination of the particle size.