Polymerizable miniemulsions were formulated in nonaqueous media, and it is
shown that these systems exhibit characteristics similar to those of aqueou
s miniemulsions. Depending on the polarity of the continuous medium and the
dispersed phase, the formulation of direct and inverse miniemulsions is po
ssible. Direct miniemulsions in nonaqueous media are exemplified by dispers
ing styrene in formamide or glycol. Inverse miniemulsions were generated wi
th the polar monomer hydroxyethyl methacrylate, acrylamide, or acrylic acid
in cyclohexane or hexadecane as the unpolar continuous phase, and the mini
emulsions were polymerized to latexes. For both the direct and inverse mini
emulsions, it was shown that during high shear dispersion a steady state of
droplet size is reached and that addition of a strong lipophobe (for inver
se systems) or ultrahydrophobe (for regular systems) is required to stabili
ze the resulting miniemulsion for sufficient times. With surface tension me
asurements, the coverage of the particles with surfactant was determined to
be incomplete. These facts are typical for the miniemulsion state; i.e., i
t is proven that organic miniemulsions indeed can be made and polymerized.