ABSTRACT
I. INTRODUCTION The numerous, practical applications of surfactants have their basis in the intrinsic duality of their molecular characteristics, namely, they are composed of a polar headgroup that likes water and a nonpolar tail group that dislikes water. A number of variations are possible in the types of the headgroup and tail group of surfactants. For example, the headgroup can be anionic, cationic, zwitterionic, or nonionic. It can be small and compact in size or an oligomeric chain. The tail group can be a hydrocarbon, fluorocarbon, or a siloxane. It can contain straight chains, branched or ring structures, multiple chains, etc. Surfactant molecules with two headgroups (bola surfactants) are also available. Further, the headgroups and tail groups can be polymeric in character, as in the case of block copolymers. This variety in the molecular structure of surfactants allows for extensive variation in their solution and interfacial properties. It is natural that one would like to discover the link between the molecular structure of the surfactant and its physicochemical action so that surfactants can be synthesized or selected specific to a given practical application.
