Specific Surface Activity of Gemini Surfactants: Mixing Effects of Alanine-type and Sulfate-type Surfactants.

This paper has described the surface chemical properties of the three kinds of Gemini surfactants from points of views of the specific surface activity and the polar moiety interactions. The specific surface activity named “Gemini effect” was defined as the ratio of surface activity of Gemini surfactant to that of the single chain surfactant with a similar molecular structure. The Gemini effects were compared among three kinds of Gemini surfactants as a function of their interchain-spacer distances. The interactions between sulfate groups and alanine groups in the mixture of Gemini and single-chain surfactants were investigated on the basis of the compositions of the adsorbed monolayer and micelles as mixing effects.