Oil droplet size manipulation applied to surfactant-free emulsion polymerization

Recently reported results indicate that heating of degassed oil in water emulsions reduces the size of the droplets and can produce a more mono-disperse dispersion, in the absence of surfactants. In this work, these results were applied to the field of emulsion polymerization, to create meta-stable, mono-disperse monomer solutions, which were then polymerized to produce stable dispersions of polymer spheres. The product particle size depended on a range of factors, including: salt concentration, type of thermal initiator, temperature changes, creaming time, pH and monomer/initiator concentration ratio.