| The dissertation studied the surface chemical properties, synergism, micelle aggregation number, viscosity of esterquaternary Gemini surfactants II-m-s, the structure such Gemini surfactants were COOCH2CH2N(CH3)2-(CH2)s–N(CH3)2CH2CH2OOCCm-1H2m+1]2+, 2Br-, m=10, 12, 14, 16, s=3, 4, 6).Under different temperatures, the surface tensions of Gemini surfactants were determined by dripping volumn method. It was found that the minimum surface tension (γcmc) declines while temperature increased. And when the space changed from 3,to 4,6, minimum surface tension (γcmc) increased, critical micelle concentration (cmc) first increased, but when S>4, cmc decreased. The thermodynamic data showed that the micellization processes for the studied surfactants were driven by entropy.The interactions in the mixed complex have been investigated separately. The cmc value of the mixture was used to computeβm, the interaction parameter in the micelle andβσ, the interaction parameter at the monolayer air–water interface. The value ofβshow there are synergism between complexes. Moreover, criterions about judging if there had synergism between surfactants have been used.The micellar properties for the concentration near above the cmc have been characterized by the aggregation number, Nagg using a steady state fluorescence quenching method.The micropolarities of mixed systems were determined from the ration of intensity of peaks (I1/I3) of the pyrene fluorescence emission spectrum.The viscosity of Gemini surfactants was studied too. The results showed that when concentration increased, the viscosity of the solution exceptⅡ-16-6 also increased. But when the shear rate increased, the viscosity showed the trend of decrease.
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