Tween 80分子在气-液界面上的吸附动力学

Adsorptive Kinetics of Aqueous Tween 80 Solutionsat the Air-Water Interface

用滴体积法测定30℃时Tween80水溶液的平衡及动态表面张力;研究了溶液浓度对动态表面张力及吸附机理的影响。结果表明,溶液浓度越大,动态表面张力数值越小。低浓度时,分子在气-液界面上的吸附受纯扩散控制,浓度增大,表面吸附为扩散-动力学控制机理。

The equilibrium and dynamic surface tensions of the aqueous Tween 80 solutions were measured by the drop volume method at 30℃. The effect of concentration on the dynamic surface tension was discussed. The adsorptive kinetics of Tween 80 at the air- water interface was investigated. The results show that the dynamic surface tension decreases with the increase Tween 80 concentration. The surface adsorption of Tween 80 molecules obeys the pure diffusion at low surfactant concentrations. At higher concentrations, however, the kinetics of adsorption of Tween 80 at the air - water interface is governed by a diffusion - kinetic - controlled mechanism.