ABSTRACT
The word surfactant derives from the contraction of the terms surface-active-agent and covers a group of molecules which are able to modify the interfacial properties of the liquids (aqueous or nonaqueous) in which they are present. The peculiar properties of these molecules reside in their amphiphilic character which stems from the fact that each surfactant molecule has both a hydrophilic part and a hydrophobic (or lipophilic) part. As a result, they concentrate at the interfaces separating immiscible phases, thereby decreasing the interfacial tension.
