Cosmetic chemistry emulsions

A research program in progress at Raltech Scientific Services is designed to find inhibitors which will prevent nitrosamine formation in cosmetic products, A review of the literature (4) indicated that the oil phase of emulsions may play an important role in nitrosation chemistry. Thus, results from studies in water alone could be misleading when reduced to practice. 

In fact, the state obtained by mixing oil and water is an important example of interfacial behavior of lic]iLid lic iiid2. Emulsions of oil-water systems are useful in many aspects of daily life, such as milk, foods, paint, oil recovery, pharmaceutical, and cosmetics. The colloidal chemistry of milk makes it the most complicated naturally made product. 

Because of the widespread applications of surface chemistry, practically all industries, knowingly or otherwise, make use of the principles of surface chemistry. Countless cosmetic and pharmaceutical products are emulsions—lotions, creams, ointments, suppositories, etc. Food emulsions include milk, margarine, salad dressings and sauces. Adhesive emulsions, emulsion paints, self-polishing waxes, waterless hand cleaners and emulsifiable insecticide concentrates are commonplace examples of emulsions, which fall within the province of surface chemistry. Other products winch function in accordance with the principles of smface chemistry include detergents of every variety, fabric softeners, antistatic agents, mold releases, dispersants and flocculants. 

Eccleston GM. Properties of fatty alcohol mixed emulsifiers and emulsifying waxes. In Florence AT, ed. Materials Used in Pharmaceutical Formulation Critical Reports on Applied Chemistry, volume 6. Oxford Blackwell Scientific, 1984 124-156. Mapstone GE. Crystallization of cetyl alcohol from cosmetic emulsions. Cosmet Perfum 1974 89(11) 31-33. 

Surfactants find apphcation in almost all disperse systems that are utilised in areas such as paints, dyestulfs, cosmetics, pharmaceuticals, agrochemicals, fibres, and plastics. Therefore, a fundamental understanding of the physical chemistry of surface-active agents, their unusual properties, and their phase behaviour is essential for most formulation chemists. In addition, an understanding of the basic phenomena involved in the application of surfactants, such as in the preparation of emulsions and suspensions and their subsequent stabilisation, in microemulsions, in wetting, spreading and adhesion, is vitally important to arrive at the correct composition and control of the system involved [1, 2]. This is particularly the case with many formulations in the chemical industry mentioned above. 

F. Auguste and F. Levy, The Physical Chemistry and Sensory Properties of Cosmetic Emulsions Application to Make-up Foundations, in T. T. Tadros, ed.. Emulsion Science and Technology, Wiley-VCH, Weinheim, 2009. 

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