Effect of Surfactant on Production of Monodispersed O/W Emulsion in Membrane Emulsification

The effect of surfactant on production of monodispersed O/W emulsion in membrane emulsification by controlled pore glass membrane was examined, with the following results. Although an appropriate amount of surfactant in the continuous water phase is indispensable, successful emulsification can be carried out with much less surfactnt than is used with conventional methods. Adding surfactant has the effect of decreasing the critical permeation pressure and spreading out the pressure range under which monodispersions may be prepared in steady state. However, when the polar group in a surfactant molecule has a charge opposite to that of the porous glass membrane surface, adsorption of surfactant on the membrane occurs and the membrane apparently becomes hydrophobic. Thus the emulsion obtained was considerably polydispersed.