抄録
The study on structure and property of soft interfaces including gas/liquid and liquid/liquid interfaces is inevitable to understand structure–function relation of more complicated molecular organizing systems such as biological membrane. Among our systematic studies on adsorbed films by interfacial tensiometry and X–ray reflection (XR), the domain formation of fluorocarbon (FC) alcohol (FC10OH) in the expanded film at the hexane/water interface was examined in terms of solute–solvent interaction, domain line tension, dipole interaction at domain boundary, and the interaction between coexisting domains. In the pure FC10diol system, the interfacial pressure π vs. area per adsorbed molecule A curve and the electron density profile manifested that the FC10diol molecules form condensed monolayer with parallel orientation and pile spontaneously to form multilayer. Furthermore, in case of mixed system of FC10diol and FC10OH, the π vs. A curves indicates that four kinds of adsorbed films, expanded, parallel condensed, normal condensed, and multilayer states, appear depending on the total concentration of the hexane solution and the solution composition in the FC10diol – FC10OH mixture. The twodimensional phase diagram (phase diagram of adsorption ; PDA) shows that FC10OH and FC10diol are miscible in the parallel condensed monolayer, while little amount of FC10diol mix with FC10OH in the condensed monolayer. The XR data analysis manifests that the parallel condensed monolayer is heterogeneous structure in which the parallel oriented FC10diol domain and normal oriented FC10OH domain coexist with each other.
