Laboratory of Macromolecular Photochemistry and Engineering, CNRS, LRC 7228, University of Haute-Alsace, ENSCMu, 3 bis rue Alfred Werner, 68093 Mulhouse Cedex, France.
Langmuir. 2013 Feb 12;29(6):1963-9. doi: 10.1021/la3030759. Epub 2013 Jan 28.
Over the past ten years, understanding the self-assembly process within mesostructured silica films has been a major concern. Our characterization approach relies on two powerful and complementary techniques: in situ time-resolved FTIR spectroscopy and ex situ solid-state NMR. As model systems, three silica/surfactant films displaying various degrees of mesostructuration were synthesized using an amphiphilic block copolymer (PEO-b-PPO-b-PEO) via a UV light induced self-assembly process. The key idea is that the hydration state of the hydrophobic PPO chain is expected to be different depending upon whether the sample is amorphous (blend) or mesostructured (segregated). With real-time FTIR experiments, we show that the methyl deformation mode can act as a signature for the PPO microenvironment so as to trace the progressive copolymer self-association throughout the irradiation time. In (1)H solid-state NMR, the dependence of the (1)H chemical shift on the PPO hydration state has been exploited to evidence the extent of mesostructuration.
在过去的十年中，了解介孔硅薄膜的自组装过程一直是人们关注的焦点。我们的表征方法依赖于两种强大且互补的技术：原位时间分辨傅里叶变换红外光谱和非原位固态核磁共振。作为模型体系，我们使用两亲嵌段共聚物（PEO-b-PPO-b-PEO）通过紫外光诱导自组装过程合成了三种具有不同程度介孔结构的硅/表面活性剂薄膜。其关键思想是，疏水 PPO 链的水合状态预计会根据样品是无定形（混合物）还是介孔（分离）而有所不同。通过实时傅里叶变换红外实验，我们表明甲基变形模式可以作为 PPO 微环境的特征，以追踪整个辐照时间中共聚物的逐步自组装。在（1）H 固态 NMR 中，利用（1）H 化学位移对 PPO 水合状态的依赖性来证明介孔结构的程度。
