Abstract

Two phase transitions, G−LE and LE−LC, of the adsorbed monolayer of the soluble surfactant 1-dodecanol at the air−water interface were observed from the dynamic surface tension measurement by using a pendant bubble tensiometer. Two constant surface-tension (γ) regions were detected in the dynamic surface-tension γ(t) profiles of different surfactant concentrations at 20 °C. They are at π = 0.75 and 17.9 mN/m. A constant γ region in dynamic γ(t) profiles indicates the existence of a 2D phase transition. These 2D phase transitions of adsorbed layer are presumed to be the coexistence of the gas (G) and liquid-expanded (LE) phases and that of the LE and liquid-condensed (LC) phases. A new phase-transition isotherm, which is possible to describe the 1-dodecanol adsorbed monolayer, is also proposed.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.