以有机酸为助表面活性剂的微乳液研究

MICROEMULSION WITH ORGANIC ACID AS COSURFACTANT

以中碳链长有机酸 C_4H_9COOH 到 C_6H_(13)COOH 为助表面活性剂,与表面活性剂 OS(油酸钠),十二烷和水四组分构成微乳液体系.研究了有机酸分子量和体系含油量对微乳液相图影响;从相图出发得到一系列 n_a/n_s 和 n_o/n_s 数据,两者关联作图得到直线,由其斜率和截距计算出有机酸从油相转移到微乳液液滴界面相的标准热力学函数△G_(0→i)~0,△H_(0→i)~0 和△S_(0→i)~0;用计算机拟合它们与有机酸的碳链长的关系式;并对其结果作了理论探讨.

An overall picture of the phase diagram of water/dodecane/organic acid/sodium oleatewas studied.We particularly discussed the effect of molecular weight of organic acid,concen-tration of dodecane and temperature on the phase diagram.The standard free energy △G_0~0■the standard enthalpy △H_0~0■and the standard entropy △S_0~0■of transfer from the constinu-ous oil phase to the interfacial region for several kinds of cosurfactants were reported.