Abstract: This paper reported the studies on the microemulsion of TritonX-100, hexanol, Water and alkane system. △G_(s→i)~0, the variation of the standard Gibbs function for alcohol (Cosurfactant) migrating from the oil phase to the interfacial phase had been determined and discussed. △S_(s→i)~0, △H_(s→i), the variation of the standard entropy and standard enthalpy respectively, were calculated accordingly on thermodynamic relations and at various temperatures. The result showed the existence of a linear relationship between the above thermodynamic function and the carbon number in the alkane skeleton. Based upon these results, an interpretation and discussion on the stability and structure of the microemulsion were given.

Key words: Microemulsion, Thermodynamic function, Alcohol, Alkane