Surface active materials including surfactant are the substances that exert a variety of functions at the interface, and so the relationship between their chemical structures and performance is very important in practical as well as academic. In this article, to control the orientation of the Rf groups on the surface with close packing, the author raised a novel concept of introduction of fluoroalkyl groups (Rf) as both (i) semifluoroalkyl (semi-Rf) and (ii) multi-chain structure, and also outlined his research results on the development of Rf end-capped oligomeric interface materials, surface modifying polymer having double semi-Rf groups into the side chains, and semi-Rf based Gemini surfactants. Furthermore, as the environment friendly surfactants, the development of corynomycolic acid and Gemini surfactants are described as well as the effects of stereochemistry in the succinic Gemini and tartaric Gemini on their functional properties.

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Recently, in order to aim the improvement of properties of the conventional single-chained surfactants, novel surfactants with various structures containing gemini-type have been designed. Gemini surfactants are known to have high surface activities such as lower critical micelle concentration (CMC) and higher efficiency in lowering the surface tension than conventional surfactants, and show unique aggregation behavior, i.e., spontaneous vesicle formation at low concentration in solution. This review describes design and synthesis, surface–active properties such as CMC and ability in reducing the surface tension, and aggregation properties in aqueous solution for (1) heterogemini surfactants with nonidentical hydrophilic groups, hybridgemini surfactants with nonidentical hydrophobic groups, environmentally acceptable gemini surfactants containing amino acid or sugar in a molecule, (2) trimeric surfactants with three alkyl chains and three quaternary ammonium headgroups in a molecule, (3) supra-long chained surfactants with one alkyl chain of C₁₈–C₂₀ and two or three hydrophilic groups.

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