This Report has been authored by:Megan Casey at Lehigh University

The droplet size distributions of miniemulsions were characterized using modified capillary hydrodynamic fractionation (CHDF), dynamic light scattering (DLS), surfactant titration, and acoustic attenuation spectroscopy (AAS). Miniemulsions with two different monomers were prepared: octadecyl methacrylate (ODMA), which represents an idealized miniemulsion in that the particle size distribution (PSD) of its polymerized latex correlates directly to its initial monomer droplet size distribution (DSD) due to ODMA's negligible water solubility; and styrene (S) which represents a typical miniemulsion. The DSDs show good agreement among the methods, despite differences in the measurement range capabilities of the instruments. AAS detected a population of micron-scale droplets, whose presence was verified by optical microscopy. Agreement diminishes as the DSDs become broader and more multimodal.