METHOD FOR PREPARING A MONODISPERSED DOUBLE EMULSION

摘要

The invention concerns a method for preparing a monodispersed double water/oil/water emulsion, characterised in that it consists in: a) subjecting a polydispersed oil-in-water emulsion Ei comprising 55 to 99 wt. % of an aqueous phase, to a controlled shearing so that a common maximum shearing is applied to the entire emulsion, so as to obtain the corresponding monodispersed invert emulsion; b) adding to said emulsion, without phase inversion, the necessary amount of diluting oil phase so that the aqueous phase of the resulting emulsion represents at least 50 wt. % of the emulsion total weight; and c) introducing the resulting emulsion into a high pressure homogenizer, together with a continuous aqueous phase, the respective amounts of said emulsion and said continuous aqueous phase being such that the resulting double emulsion comprises up to 50 wt. % of invert emulsion droplets relative to the emulsion total weight, said continuous aqueous phase comprising a hydrophilic surfactant concentration not more that 0.02 times the critical micellar concentration.