抄録
The surface properties and structures of mixed monolayers were studied to establish an assembled model for a detergent system. Surface pressure-area curves of the mixed monolayers of arachidic acid and cellulose derivatives showed a sinuous aspect with apparent inflection points. The curves of the mixed monolayers were consistent with the isotherms calculated on the assumption of the fractional summation in isotherms of pure monolayers, thus demonstrating the separation of molecules in a mixed monolayer, LB films with a single layer were prepared as a mixed monolayer of arachidic acid and cellulose derivative at a mixing ratio of 1/1. The monolayer was transferred onto a specimen grid covered with carbon supporting film at different surface pressures by the horizontal attachment method. LB film structures were then observed by dark-field electron microscopy. Micrographs of the films indicated inhomogeneous structures, thus showing phase separation in the mixed monolayer. The microscopically phase-separated monolayer would thus appear usable as a model detergent system in which arachidic acid is incorporated into the cellulose derivative.
