Shear rupturing of complex fluids: Application to the preparation of quasi-monodisperse water-in-oil-in-water double emulsions

Quasi-monodisperse emulsions can be obtained by shearing a crude polydisperse one within a very narrow gap (Langmuir 1997, 4600-4613). In this paper, we apply the emulsifying technique developed for simple emulsions to fabricate double emulsions of controlled size. We first prepare quasi-monodisperse and concentrated water-in-oil emulsions using a Couette mixer. This inverted emulsion is emulsified in an aqueous phase using the same apparatus. We obtain water-in-oil-in-water double emulsions made of oily globules containing smaller water droplets, both colloids having well-defined and controlled diameter.