Properties of Binary Surfactant Systems of a Cationic Ester-Containing Gemini Surfactant with Some Conventional Surfactants in Aqueous Solutions

Abstract Gemini surfactant, N,N′-bis(dimethyl ethyl dodecane)ethyl ether dibromide was synthesized and symbolized as II-12-EO 2 . The surface chemical properties and micelle behaviors of II-12-EO 2 with poly (ethylene oxide) (PEO) lauryl ether (C 12 E 6 ) and sodium dodecyl sulfate (SDS) were investigated in 0.1 mol · L −1 sodium bromide aqueous solution at 313 K using surface tension measurements and steady-state fluorescence spectroscopy. The critical micelle concentration (cmc) of II-12-EO 2 is 1.99 × 10 −4 mol · L −1 and the aggregation number is 23. The cmc values of the two binary systems with different molar fractions are all lower than those of pure constituent surfactants, and the aggregation numbers of the binary systems are all larger than that of II-12-EO 2 . The interaction parameters β of the two binary systems were calculated, and the negative values of β indicate the existence of synergism in surface tension reduction efficiency, mixed micelle formation and surface tension reduction effectiveness.