十烷基硫酸钠-全氟辛酸钠混合表面活性剂在四氯乙烯-水界面上的吸附及胶团形成

At The Interface (Tetrachloroethylene/Aqueous Solution) Adsorption and Micellar Formation for the Mixed Aqueous Solutions of Sodium Decylsulfate- Sodium Perfluorooctanoate Surfactants

测定了在30℃、总离子强度为0.1m时不同比例混合的十烷基硫酸钠(C_(10)SNa)-全氟辛酸钠(7CFNa)在四氯乙烯-水界面的界面张力,研究混合溶液的界面性质及胶团形成,结果表明:(1) 7CFNa与C_(10)SNa在混合溶液中,基本上各自独立形成胶团;(2)混合表面活性剂在四氯乙烯-水界面上的吸附与在正庚烷-水界面上吸附规律相同;(3) 测定C_(10)SNa、7CFNa在不同油-水界面上的界面张力,证实碳氟链与碳氯链之间具有“互憎性”。

In this paper the adsorption and micelle behavior of mixed solution of C_(10)H_(21)SO_(4)Na and C_(7)F_(15) COONa at tetrachloroethylene/aqueous solution interface have been studied by determining the interfacial tension with the drop-volume method, and the amount of adsorption has been calculated by applying the Gibbs adsorption equation.The results are shown that( Ⅰ ) there is no completely misciblc micelle but essentially the individual micelle(C_(10)H_(21)SO_(4)Na and C_(7)F_(15)CCONa) in the mixed aqueous solution;(2) the adsorption of C_(7)F_(15)COONa at telrachloroethylene/ aqueous solution interface is weaker than of C_(3)0H_(21)SO_(4)Na and just the same case as that at heptane/aqueous solution interface;(3)at heptane/H_(2)O, carbon tetr-achloridc/H_(2)O and cyclohexane/H_(2)O interface, the interface activity of C_(10)H_(21)SO_(4)Na is higher than that of C_(7)F_(15)COONa;and at poly-trifluorochloroethylene/H_(2)O interface the reverse is true. All of these indicate the real existence of “mutual phobicity” between the fluorocarbon and chlorocarbon chains.