ABSTRACT
Surfactant agents are amphipathic molecules constituted by a hydrophilic (it can be nonionic, positively or negatively charged, or amphoteric) and a hydrophobic domain (generally a lipid). The surfactant properties are marked by the interactions of these amphipathic molecules with different polarity degrees and hydrogen bonds at uid- uid or uid-solid interfaces, such as oil/water, air/water, and air/solid, reducing the interfacial tension, the surface tension, and changing the wettability between these coupled phases. Usually, the surfactants are characterized by their physicalchemical properties, such as critical micelle concentration (CMC), and hydrophiliclipophilic balance (HLB), their chemical structure, and their charge.
