Sharma K Shivaji, Rodgers Christopher, Palepu Rama M, Rakshit A K
Department of Chemistry, Faculty of Science, M.S. University of Baroda, Vadodara, 390 002, India.
J Colloid Interface Sci. 2003 Dec 15;268(2):482-8. doi: 10.1016/j.jcis.2003.07.038.
The interaction between the alkanediyl-alpha,omega-type cationic gemini surfactant, [(C(16)H(33)N(+)(CH(3))(2)(CH(2))(4)N(+)(CH(3))(2)C(16)H(33))2Br(-)], 16-4-16 and the conventional nonionic surfactant [CH(3)(CH(2))(10)CH(2)(OCH(2)CH(2))(6)OH], C(12)E(6) in aqueous medium has been investigated. The critical micelle concentrations of different mixtures have been measured by surface tension using a du Nouy tensiometer in aqueous solution at different temperatures (303, 308, and 313 K). Maximum surface excess (Gamma(max)) and minimum area per molecule (A(min)) were evaluated from a surface tension vs log(10)C (C is concentration) plot. The cmc value of the mixture was used to compute beta(m), the interaction parameter. The beta(sigma), the interaction parameter at the monolayer air-water interface, was also calculated. We observed synergism in 16-4-16/C(12)E(6) system at all concentration ratios. The micelle aggregation number (N(agg)) has been measured using a steady state fluorescence quenching method at a total surfactant concentration approximately 2 mM at 25 degrees C. The micropolarity and the binding constant (K(sv)) of mixed systems were determined from the ratio of intensity of peaks (I(1)/I(3)) of the pyrene fluorescence emission spectrum. The micellar interiors were found to be reasonably polar. We also found, using Maeda's concept, that the chain-chain interactions are very important in this system.
已对链烷二基-α,ω型阳离子双子表面活性剂[(C₁₆H₃₃N⁺(CH₃)₂(CH₂)₄N⁺(CH₃)₂C₁₆H₃₃)₂Br⁻]，即16-4-16与传统非离子表面活性剂[CH₃(CH₂)₁₀CH₂(OCH₂CH₂)₆OH]，即C₁₂E₆在水介质中的相互作用进行了研究。在不同温度（303、308和313 K）下，使用杜诺依张力计通过表面张力测量了不同混合物的临界胶束浓度。从表面张力对log₁₀C（C为浓度）的图中评估了最大表面过剩量（Γ(max)）和每个分子的最小面积（A(min)）。混合物的临界胶束浓度值用于计算相互作用参数β(m)。还计算了在单分子层气-水界面处的相互作用参数β(σ)。我们观察到在所有浓度比下16-4-16/C₁₂E₆体系中都存在协同作用。在25℃下，使用稳态荧光猝灭法在总表面活性剂浓度约为2 mM时测量了胶束聚集数（N(agg)）。混合体系的微极性和结合常数（K(sv)）由芘荧光发射光谱的峰强度比（I(1)/I(3)）确定。发现胶束内部具有适度的极性。我们还利用前田的概念发现，链-链相互作用在该体系中非常重要。
