ABSTRACT
The properties and characteristics of surfactants are mostly related to surface and interfacial phenomena, and the formation of aggregates, which are primarily a function of their concentration in use and their structural features. Environmental cleanup processes use surfactants for the dispersion of pollutants from oil and gas activities into water and enhance their biodegradation. Most surfactant properties are related to interfacial phenomena, which are widely useful in the formulation and application of cosmetic products. A parallel between the definition of cosmetics and the applications, criteria and restrictions in the selection of surfactants can be made to illustrate how important these ingredients are for cosmetic products, from the simplest formulation to the most complex ones. Some anionic surfactants used in cosmetics are sensitive to water hardness and do not foam in the presence of calcium and magnesium ions. Foam is a psychological and functionally important factor with some surfactants, especially those used for the production of shampoos, toothpastes and shave products.
