Abstract
Dynamic surface tension and its diffusional decay have been studied with four different polydisperse C12E7 at different temperatures and different concentrations. The CMC and the headgroup area from equilibrium surface tension were shown with polydispersity and temperature. The chain length of oxyethylene on the surface was derived from comparison between the headgroup area of monodisperse dodecyl ethoxylates and that of polydisperse C12E7. The values for (Deff/D) were deduced with a diffusion-controlled adsorption model using parameters obtained from equilibrium surface tension. It was shown at short adsorption time that molecules were really adsorbed onto the surface in a diffusion-controlled manner. At a comparably long adsorption time, the ratios (Deff/D) were calculated by assuming the selective adsorption onto the surface. The modified Arrhenius-type equation was proposed by putting a concentration term in front of the exponential terms. The modified Arrhenius-type equation gave Ea=30 kJ/mole for this system. Ea directly derived without an Arrhenius plot was between 9 to 11 kJ/mole. It was an indication that the activation energy alone was not enough to explain the decay of dynamic surface tensions.
Published Version
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 callDisclaimer: 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.
