抄録
Properties and structures of adsorbed films on mixed aqueous solutions of sodium dodecyl sulfate (SDS) and a trace amount of 1-dodecanol (DD) were investigated by film balance experiments, a Brewster angle microscopy (BAM), and a quick X-ray reflectometry (q-XR) at 20 C. Pouring the aqueous solutions of the surfactants into a trough, the surface pressure first increased up to certain maximum values due to adsorption of the surfactants at the air/solution interface, but after a while it started to decrease probably due to evaporation of DD. BAM observation showed formation of holes of fluid phase in homogeneous condensed-phase monolayers in the course of surface pressure decrease. The q-XR technique was applied to the adsorbed films at the beginning stage of destabilization in order to characterize the film structures at the molecular level.
