脂肪胺聚氧乙烯醚与LAS复配体系的表面活性

Surface activity of mixed system polyoxyethylene alkylamine and sodium dodecylbenzene sulfonat

研究了脂肪胺聚氧乙烯醚(AE18)和十二烷基苯磺酸钠(LAS)在水溶液中相互作用。通过表面张力法测定了AE18和LAS不同比例下的临界胶束浓度(CMC)。两种表面活性剂以任何比例复配时,复配体系的CMC都明显低于LAS的CMC;并且在摩尔比n(LAS)∶n(AE18)=1∶9时,混合体系的CMC比任何单一表面活性剂CMC都低。复配体系达到CMC时的表面张力(γCMC)介于两种表面活性剂之间。运用Clint提出的理想混合胶团公式对CMC值进行了计算,与CMC实验值比较,发现随AE18摩尔分数的增加,CMC的实验值与计算值相近。

The interaction between polyoxyethylene alkylamine （AE 18） and sodium dodecylbenzene sulfonat （LAS） in aqueous solution have been investigated. The critical micelle concentrations （CMC） of different mixtures were measured by surface tension measurement. The results suggested that the CMC of different mixtures at any molar ratio is lower than that of LAS, it is also found that when the molar fraction of LAS in the mixture is 0.1, the CMC of mixtures system is lower than that of either pure AE 18 or LAS surfactant. Surface tention （γCMC） of mixtures system at CMC is between that of two surfactants. After comparing experimental CMC with the calculating CMC which is applied the theories of Clint, we found with the increase in molar fraction of AE18 experimental CMC and calculate CMC results are similar.