Abstract: The interaction between N, N-diethylaniline (DEA) and SDS/n-C5H11OH/H2O microemulsion was investigated by cyclic voltammetric method. DEA has two oxidation peaks in both O/W and W/O microemulsions, and the potential difference is only about 0.099 V between the two peaks ( Table 1, Fig.2).Since the energy needed for the radical cation DEA＋● losing an electron to form DEA2＋ is about 0.50 V (E(DEA /DEA＋●)－E(DEA＋●/DEA)≈0.50 V),the two peaks are both produced by DEA molecule losing an electron to form DEA＋●. The results indicate that DEA molecules can reside in the membrane phase of O/W and W/O microemulsion droplets with two ways. Some of them are located in the membrane phase of microemulsion near to the polar head of surfactant and cosurfactant, and others are located in the side of the hydrophobic tail of the surfactant. The distribution between the two locations depends on the structures and compositions of the microemulsions.

Key words: Cyclic voltammetry, Microemulsions, N,N-diethylaniline, Sodium dodecyl sulfate(SDS)