Macroemulsion

Macroemulsions are kinetically stabilized mixtures of at least two immiscible liquids where one of the liquids has droplets with a diameter greater than 0.1 μm. Macroemulsions scatter light effectively and therefore appear milky, because their droplets are greater than a wavelength of light. They are part of a larger family of emulsions along with microemulsions. As with all emulsions, one phase serves as the dispersing agent. It is often called the continuous or outer phase. The remaining phase(s) are disperse or inner phase(s), because the liquid droplets are finely distributed amongst the larger continuous phase droplets. This type of emulsion is thermodynamically unstable, but can be stabilized for a period of time with applications of kinetic energy. Surfactants (emulsifiers) are used to reduce the interfacial tension between the two layers, and induce macroemulsion stability for a useful amount of time.