This review covers equilibrium and dynamic aspects of surface tension and adsorption,primarily of single non micellar or premicellar and micellar surfactants at the air/water interface.Equilibrium tension data have be...This review covers equilibrium and dynamic aspects of surface tension and adsorption,primarily of single non micellar or premicellar and micellar surfactants at the air/water interface.Equilibrium tension data have been related to the Langmuir adsorption equilibrium isothem and the Gibbs isothem.A minute description of the measurement and the curve analysis of the dynamic surface tension is given.Dynamic adsorption models with the diffusioncontrolled and mixed kinetic mechanisms are discussed in some detail and applied to several sets of data.Apparent diffusion coefficients,inferred from dynamic tension data,and kinetic adsorption parameters,derived from application of the models to the data,are presented and critically evaluated.The adsorption of most of the surfactants examined is slower than predicted by diffusion controlled models.Exceptions are mostly non ionic surfactants and certain alcohols.展开更多
The surface tensions of water and aqueous lithium bromide (LiBr) with 2-ethyl-1-hexa- nol (2EH) and 1-octanol were measured using Wilhelmy plate method, and the oscillation of sur-face tension under the open condition...The surface tensions of water and aqueous lithium bromide (LiBr) with 2-ethyl-1-hexa- nol (2EH) and 1-octanol were measured using Wilhelmy plate method, and the oscillation of sur-face tension under the open condition for LiBr solution was observed. The dynamic surface ten-sions of water and LiBr solution in the presence of the 2EH and 1-octanol vapor were measured in this paper. The results showed that the additives vapor could obviously affect surface tension. For water, the dynamic surface tension was also affected by the mass of the tested liquid; however, for LiBr solution, the dynamic surface tension was not related to the mass of the tested solution. Ac-cording to the experimental results, the hypothesis that surface tension varies linearly with the surface excess concentration is advanced, which could overcome the limit of Gibbs equation. The equations of surface absorption and desorption are modified, the units of the adsorption coefficient and desorption coefficient are unified; the effects of the liquid and vapor of additive on the surface tension are unified; the theoretical relations of the static surface tension and dynamic surface ten-sion with the relative contents of the liquid and vapor of additive are obtained under the combined actions of them; the theoretical equations are validated by the experiments results.展开更多
文摘This review covers equilibrium and dynamic aspects of surface tension and adsorption,primarily of single non micellar or premicellar and micellar surfactants at the air/water interface.Equilibrium tension data have been related to the Langmuir adsorption equilibrium isothem and the Gibbs isothem.A minute description of the measurement and the curve analysis of the dynamic surface tension is given.Dynamic adsorption models with the diffusioncontrolled and mixed kinetic mechanisms are discussed in some detail and applied to several sets of data.Apparent diffusion coefficients,inferred from dynamic tension data,and kinetic adsorption parameters,derived from application of the models to the data,are presented and critically evaluated.The adsorption of most of the surfactants examined is slower than predicted by diffusion controlled models.Exceptions are mostly non ionic surfactants and certain alcohols.
基金supported by the Special Foundation of Engineering Science School of USTCthe National Natural Science Foundation of China(Grant No.50206020).
文摘The surface tensions of water and aqueous lithium bromide (LiBr) with 2-ethyl-1-hexa- nol (2EH) and 1-octanol were measured using Wilhelmy plate method, and the oscillation of sur-face tension under the open condition for LiBr solution was observed. The dynamic surface ten-sions of water and LiBr solution in the presence of the 2EH and 1-octanol vapor were measured in this paper. The results showed that the additives vapor could obviously affect surface tension. For water, the dynamic surface tension was also affected by the mass of the tested liquid; however, for LiBr solution, the dynamic surface tension was not related to the mass of the tested solution. Ac-cording to the experimental results, the hypothesis that surface tension varies linearly with the surface excess concentration is advanced, which could overcome the limit of Gibbs equation. The equations of surface absorption and desorption are modified, the units of the adsorption coefficient and desorption coefficient are unified; the effects of the liquid and vapor of additive on the surface tension are unified; the theoretical relations of the static surface tension and dynamic surface ten-sion with the relative contents of the liquid and vapor of additive are obtained under the combined actions of them; the theoretical equations are validated by the experiments results.
