Smarsly Bernd, Gibaud Alain, Ruland Wilhelm, Sturmayr Dietmar, Brinker C Jeffrey
Max-Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany.
Langmuir. 2005 Apr 26;21(9):3858-66. doi: 10.1021/la046916r.
Oriented mesostructured surfactant-silica nanocomposite thin films with a 2D hexagonal mesostructure of cylindrical micelles were prepared by evaporation-induced self-assembly using two different nonionic Brij surfactants and studied by small-angle X-ray scattering in symmetric reflection (SRSAXS) and grazing incidence (GISAXS) geometries. A novel SRSAXS evaluation approach was applied that allowed a good fitting of the SRSAXS data over almost the whole range of scattering vectors. Aside from the cylinder radius and the lattice parameter, the approach provided accurate values for the polydispersity of the micelles, lattice distortions, and preferred orientation. These analyses revealed a significant rise of the micelle radius and accordingly the lattice parameter upon an increase in the ratio surfactant/SiO(2), attributable to a decrease in the solubilization of the poly(ethylene oxide) (PEO) chains by water, in agreement with Monte Carlo simulations. Furthermore, the SRSAXS analysis was successfully applied to the corresponding mesoporous films for the determination of pore sizes.
通过蒸发诱导自组装，使用两种不同的非离子型Brij表面活性剂制备了具有圆柱形胶束二维六方介观结构的定向介观结构表面活性剂-二氧化硅纳米复合薄膜，并通过对称反射小角X射线散射（SRSAXS）和掠入射小角X射线散射（GISAXS）几何结构进行了研究。应用了一种新颖的SRSAXS评估方法，该方法能够在几乎整个散射矢量范围内对SRSAXS数据进行良好拟合。除了圆柱半径和晶格参数外，该方法还提供了胶束多分散性、晶格畸变和择优取向的准确值。这些分析表明，随着表面活性剂/SiO₂ 比例的增加，胶束半径以及相应的晶格参数显著增大，这归因于水对聚环氧乙烷（PEO）链增溶作用的降低，这与蒙特卡罗模拟结果一致。此外，SRSAXS分析成功应用于相应的介孔薄膜以确定孔径。
