New environmental friendly dicephalic amine dichlorides: Nonequivalent adsorption and interactions with model polyelectrolyte

► Nonequivalent adsorption of new dicephalic Cn(DAPACl)2 at the air/water interface was described in terms of the advanced model of multicharge cationic surfactant adsorption. ► In the presence of model PSS the dichloride C12(DAPACl)2 as well as the respective bromide and methylsulfate derivatives form surface active complexes at very low polymer concentration. ► The existence of strong surface polyelectrolyte/surfactant interactions results in a synergistic lowering of surface tension.