X-ray reflectivity measurements were applied to hexadecane wetting film on aqueous solutions of hexadecyltrimethylammonium bromide (CTAB) and tetradecyltrimethylammonium bromide (TTAB). In both cases, the monolayers in which oil molecules are penetrated from hexadecane droplets into surfactant-adsorbed films were found at room temperature. Upon cooling, they showed first-order freezing transitions, however, it was also confirmed that the structures of freezing films were qualitatively different: hexadecane molecules were frozen together with CTAB to form mixed solid monolayer in CTABhexadecane while the frozen hexadecane monolayer wetted mixed liquid monolayer in TTABhexadecane.
All Science Journal Classification (ASJC) codes
- 化学 (全般)