DDAB MICROEMULSIONS - DEPENDENCE ON THE OIL CHAIN-LENGTH

In this work we discuss the oil chain length dependence of ternary DDA B microemulsions, comparing decane, dodecane, and tetradecane. With do decane and shorter alkanes the L-2 microemulsion phase extends to the oil corner, while with tetradecane the microemulsion phase forms an is land in the center of the ternary phase diagram. We present new NMR se lf-diffusion and N-14 NMR relaxation data, where the three systems are compared at similar compositions. It is argued that the disconnection of the microemulsion phase from the oil corner with longer oils is as sociated with the Winsor IT to Winsor III transition known from nonion ic microemulsions. It follows that the tetradecane microemulsion has, in a major part, a monolayer rather than a bilayer structure.