文献类型：期刊文献

英文题名：Surfactant Adsorption onto Interfaces: Measuring the Surface Excess in Time

作者：He Yunfei[1,2,3];Shang Yazhuo[2,3];Liu Honglai[2,3];Dominique, Langevin[1];Anniina, Salonen[1]

机构：[1]Univ Paris 11, Phys Solides Lab, UMR 8502, F-91405 Orsay, France;[2]E China Univ Sci & Technol, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[3]E China Univ Sci & Technol, Dept Chem, Shanghai 200237, Peoples R China

年份：2012

卷号：28

期号：6

起止页码：3146

外文期刊名：LANGMUIR

收录：;EI(收录号：20120814787011);WOS:【SCI-EXPANDED(收录号:WOS:000300138500012)】；

基金：Y.H thanks the China Scholarship Council for the financial support of the thesis and the National Natural Science Foundation of China (Project No. 21173079).

语种：英文

外文关键词：Adsorption - Nonionic surfactants

摘要：We propose a direct method to measure the equilibrium and dynamic surface properties of surfactant solutions with very low critical micellar concentrations (CMC) using a pendant drop tensiometer. We studied solutions of the nonionic surfactant hexaethylene glycol monododecyl ether (C12E6) and of the ionic surfactant hexadecyl trimethyl ammonium bromide (CTAB) with concentrated sodium bromide (NaBr). The variation of the surface tension as a function of surface concentration is obtained easily without the need for complex models and compares well with the result obtained using the Gibbs adsorption equation. The time-dependent surface concentration of each surfactant was also measured, and the adsorption process was found to be diffusion-controlled. The diffusion coefficients of the two surfactants can be extracted from the data and were found in very good agreement with literature values, further validating the method.