Kairaliyeva T, Aksenenko E V, Mucic N, Makievski A V, Fainerman V B, Miller Reinhard
Max-Planck-Institut für Kolloid-und Grenzflächenforschung, Potsdam, Germany.
Institute of Colloid Chemistry and Chemistry of Water, Kyiv (Kiev), Ukraine.
J Surfactants Deterg. 2017;20(6):1225-1241. doi: 10.1007/s11743-017-2016-y. Epub 2017 Sep 4.
Surface tension and dilational viscoelasticity of solutions of various surfactants measured with bubble and drop profile analysis tensiometry are discussed. The study also includes experiments on the co-adsorption of surfactant molecules from a solution drop and alkane molecules from saturated alkane vapor phase. Using experimental data for 12 surfactants with different surface activities, it is shown that depletion due to adsorption of surfactant from the drop bulk can be significant. An algorithm is proposed quantitatively to take into consideration the depletion effect which is required for a correct description of the co-adsorption of alkanes on the solution drop surface and the correct analysis of experimental dynamic surface tension data to determine the adsorption mechanism. Bubble and drop profile analysis tensiometry is also the method of choice for measuring the dilational viscoelasticity of the adsorbed interfacial layer. The same elasticity moduli are obtained with the bubble and drop method only when the equilibrium surface pressures are sufficiently small (Π < 15 mN m). When the surface pressure for a surfactant solution is larger than this value, the viscoelasticity moduli determined from drop profile experiments become significantly larger than those obtained from bubble profile measurements.
讨论了用气泡和液滴轮廓分析张力测定法测量的各种表面活性剂溶液的表面张力和扩张粘弹性。该研究还包括从溶液液滴中表面活性剂分子与饱和烷烃气相中烷烃分子的共吸附实验。利用12种具有不同表面活性的表面活性剂的实验数据表明，由于表面活性剂从液滴本体中吸附而导致的耗尽可能很显著。提出了一种算法，定量考虑耗尽效应，这对于正确描述烷烃在溶液液滴表面的共吸附以及正确分析实验动态表面张力数据以确定吸附机理是必需的。气泡和液滴轮廓分析张力测定法也是测量吸附界面层扩张粘弹性的首选方法。仅当平衡表面压力足够小（Π < 15 mN m）时，气泡法和液滴法才能获得相同的弹性模量。当表面活性剂溶液的表面压力大于该值时，由液滴轮廓实验确定的粘弹性模量明显大于从气泡轮廓测量获得的模量。
