Search

A series of gemini quaternary ammonium surfactants containing carboxylate counterion with the formula C 17 H 35 CONH(CH 2 ) 2 N + (CH 3 ) 2 (CH 2 ) 2 N + (CH 3 ) 2 (CH 2 ) 2 NHCO C 17 H 35 ·2Y (Y=HCOO - , CH 3 COO - , CH 3 CHOHCOO - ) have been synthesized by a counterion conversion process and characterized by Fourier transform infrared spectroscopy and mass spectroscopy. It is found that these surfactants reduce the surface tension of water to a minimum value of 26.78 mN·m -1 at a concentration of 1.21 ×10 -5 mol·L -1 . TEM images reveal that aggregates with vesicles or tubular structure are spontaneously formed in these surfactants aqueous solution with the concentration of 1×10 -3 mol·L -1 . It is also found that they are effective corrosion inhibitors for A3 steel in acid solution and have superior antibacterial activity at a concentration of 0.1g·L -1 .

The surface properties of the mixtures of zwitterionic surfactants derived from olive oil (carboxylbetaine-OCB and sulfobetaine-OSB) and anionic surfactant-sodium dodecylbenzene sulfonate (SDBS) at different mole fractions were investigated by surface tension measurement. The influences of the addition of inorganic salts (NaCl, MgCl2) on the surface activities in OCB/SDBS and OSB/SDBS systems were also studied. The result shows that the two mixed systems possess lower CMC values and higher surface activities over all mole fractions studied than their individual components. Meanwhile, the noticeable synergistic interactions of OCB/SDBS and OSB/SDBS were determined by the micelle interaction parameter (βm) according to regular solution theory. It is observed that the mixed OCB/SDBS system at αOCB = 0.6 and the mixed OSB/SDBS system at αOSB = 0.6 exhibit the strongest synergism. In addition, the binary surfactant mixtures performed better surface activities upon addition of inorganic salts and the different valence state of mental ions of the inorganic salts had different surface ability effect on the mixed system: Mg2+ > Na+. [ABSTRACT FROM AUTHOR]