New Cationic Surfactants with Sulfonium Headgroups

The synthesis of a new class of cationic surfactants with sulfonium headgroups is presented. The use of common and easily accessible reactants allows a broad variation of the molecular surfactant structures, i.e., the synthesis of not only linear homologues but also of bola- or star-shaped surfactants. Surface tension measurements were used to determine the critical micelle concentration (cmc) and the surface excess concentration Γ ∞ . The lyotropic phase behavior was investigated by polarized light optical microscopy. The influence of the hydrophobic chain length, the molecular structure of the headgroup, and the counterion on the surfactant properties is discussed.