辛酸钠-醇-水溶液体系的表面化学性质研究

辛酸钠水溶液中加入不同种类醇后，使溶液最低表面张力及临界胶束浓度降低，在所研究醇中，最有效提高表面活性的是正己醇，即较长碳链醇更易参加胶团形成和在表面吸附，另外实验还发现加入醇引起胶束解离度增加，这是由于醇碳氢链可插入形成胶束的表面活性剂分子碳氢链中使胶团表面电荷密度降低，使反离子易于解离。

THE PROPERTIES OF SURFACIAL CHEMISTRY OF SODIUM OCTANOATEALCOHOL-WATER SOLUTIONS

The effects of the addition of alcohol(n butanol;secbutanol,n pentanol,iso pentanol,n octanol)on surface tension and the critical micelle concentration(CMC) have been studied.Addition of alcohol to surfactant solution results in the decreases of surface tension and CMC,and the increases in micelle ionzation degrees.Because larger hydrophobic content may readily tend to pass into micellar phase and adsorb in gas liquid surface,the n hexanol is the most effective alcohol for enhancing surfacial activity as found in this work.It is expected that the hydrophilic part of alcohol molecule is anchored in the micelle while OH group is sandwiched between COO - groups,then decreases micellar charge desity and consequently increased the micelle ionzation degrees. The studies of nonionized acid show that acid can be absorbed at the gas water surface preferentially.Long chained anions are absorbed less closely and at much higher concentration.The presence of acid in surfacial layer can enchance surfacial activity.The function of nonionized acid is very similar to that of alcohol as discussed above.