Effect of Organic Ammonium Salts on the Surface Activity and Solubility of Fluorocarbon Surfactant

测定了一系列有机铵盐与一种全氟烷磺酸盐1：1混合体系水溶液的表面张力，由此研究有机铵盐对碳氟表面活性剂表面活性及溶度的影响，导出应用于此种混合体系的Gibbs吸附公式，并讨论了混合体系中两表面活性组分的表面分子相互作用和表面层的结构．The surface tension of the aqueous solutions of organic ammonium salts and potasium 3-oxa-perfluorononane-sulfonate (FC-53) has been determined. The effect of organic ammonium salts on the surface activity and solubility of FC-53 has been investigated. It is found that the non-surface active ammonium salts ((CH3)(3)NHCl, ((C2H5)(3)NHCl,(HOC2H4)(3)NHCl,and (C2H5)(4)NBr) and the surface active ones (n-C4H9)(4)NBr and n-C8H17N(CH3)(3)Br) all can enhance the surface activity of FC-53, and the former can make FC-53 more water-soluble whereas the latter can not. The Gibbs adsorption equations for these mixed systems have been derived and the molecular interactions and compositions in the surface layers, especially for the systems containing surface active organic ammonium salts, have been obtained. It is concluded that, owing to the strong attraction (in addition to the hydrophobic interaction) between the two oppositely charged surface active ions, the mixtures with surface active organic ammonium salts are very surface active and the surfactant hydrophobic chains are close-packed with the orientation toward air, and for (n-C4H9)(4)N+ group, the n-butyl chain is not stretched but has a bending conformation.SCI(E)中文核心期刊要目总览(PKU)中国科学引文数据库(CSCD)111976-9801