{"id":3118,"date":"2015-09-25T08:00:03","date_gmt":"2015-09-25T14:00:03","guid":{"rendered":"https:\/\/www.ulprospector.com\/knowledge\/?p=3118"},"modified":"2018-07-11T12:29:29","modified_gmt":"2018-07-11T18:29:29","slug":"pcc-microemulsions-explained","status":"publish","type":"post","link":"https:\/\/ulprospector.ul.com\/3118\/pcc-microemulsions-explained\/","title":{"rendered":"Microemulsions Explained"},"content":{"rendered":"
\"Makeup
Makeup removers represent one of the main applications for microemulsions<\/figcaption><\/figure>\n

The term \u201cmicroemulsion<\/a>\u201d was first used by Schulman1<\/sup>\u00a0in 1959 to describe a multiphase system consisting of water,\u00a0oil<\/a>,\u00a0surfactant<\/a>\u00a0and\u00a0alcohol<\/a>, which forms transparent solutions. MEs are thermodynamically stable micellar dispersions with a particle size of 10-100 nm that instantly form with simple mixing. They are low-viscosity systems containing an aqueous phase, oil phase, surfactant, and a\u00a0cosurfactant<\/a>.<\/p>\n

The cosurfactant, typically a\u00a0polyol<\/a>\u00a0or\u00a0alkanol<\/a>, helps reduce the interfacial tension, which in turn helps to reduce the size of the dispersed droplets and normally is water-insoluble. The presence of the cosurfactant also reduces the rigidity of the interfacial film, leading to the formation of a bicontinuous structure typical of microemulsions.<\/p>\n

MEs can exist as oil in water, water in oil, or bicontinuous emulsions that are oil or water soluble. ME formation is dependent on surfactant type\/structure and can be formed using\u00a0ionic<\/a>\u00a0or\u00a0nonionic surfactants<\/a>. If the surfactant is ionic and contains a single hydrocarbon chain like\u00a0sodium lauryl sulfate<\/a>, MEs will only form if a co-surfactant and\/or electrolyte is present. With double chain ionics and some non-ionic surfactants, a cosurfactant is frequently not necessary.<\/p>\n

The main current marketed applications for MEs include\u00a0makeup removers<\/a>, stable oil in water emulsion based\u00a0wipes<\/a>,\u00a0silicone free hair conditioning shampoos<\/a>, and as\u00a0fragrance<\/a>\u00a0and\u00a0essential oil<\/a>\u00a0solubilization.<\/p>\n

Note, Nano emulsions are also clear colloidal dispersions but are not true MEs since they are not thermodynamically stable and frequently require high shear processing to form.<\/p>\n

Advantages of Microemulsions<\/h4>\n