Biggs Simon, Labarre Marie, Hodges Chris, Walker Lynn M, Webber Grant B
Institute of Particle Science and Engineering, The School of Process, Environmental and Materials Engineering, The University of Leeds, Leeds, United Kingdom.
Langmuir. 2007 Jul 17;23(15):8094-102. doi: 10.1021/la700708g. Epub 2007 Jun 20.
The adsorption of rodlike polymer-micelle aggregates of cetyltrimethylammonium 4-vinylbenzoate (p-C16TVB) at the silica-water interface has been characterized using a combination of quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM) studies. Adsorption isotherm data, recorded by QCM-D, indicate a two-stage mechanism: an adsorbed film of free CTA+ ions is initially produced at low concentrations until the surface is charge reversed, whereupon the weakly anionic aggregates can adsorb and the adsorbed mass is seen to increase dramatically. The adsorbed rodlike micelle aggregates are seen to form a close-packed monolayer from AFM images with a high degree of order over micrometer length scales. AFM force-distance data indicate that the adsorbed aggregates retain their cylindrical structure and little or no flattening is seen. Rinsing of the film did not result in removal of the adsorbed layer, and the persistence of these nanoscale ordered films at the solid-liquid interface suggests many possible applications.
采用石英晶体微天平与耗散监测（QCM-D）以及原子力显微镜（AFM）研究相结合的方法，对十六烷基三甲基铵4-乙烯基苯甲酸酯（p-C16TVB）棒状聚合物-胶束聚集体在二氧化硅-水界面的吸附进行了表征。QCM-D记录的吸附等温线数据表明存在两阶段机制：在低浓度下最初会形成由游离CTA+离子组成的吸附膜，直到表面电荷反转，此时弱阴离子聚集体能够吸附，吸附质量会显著增加。从AFM图像可以看出，吸附的棒状胶束聚集体形成了紧密堆积的单分子层，在微米长度尺度上具有高度的有序性。AFM力-距离数据表明，吸附的聚集体保留了其圆柱形结构，几乎没有观察到扁平化现象。冲洗该膜不会导致吸附层的去除，并且这些纳米级有序膜在固液界面的持久性表明了许多可能的应用。
