Hniopek Julian, Meurer Josefine, Zechel Stefan, Schmitt Michael, Hager Martin D, Popp Jürgen
Department Spectroscopy & Imaging, Leibniz Institute of Photonic Technology Albert-Einstein-Str. 9 0775 Jena Germany
Institute of Physical Chemistry (IPC), Friedrich Schiller University Jena Helmholtzweg 4 07743 Jena Germany.
Chem Sci. 2023 Jun 6;14(26):7248-7255. doi: 10.1039/d3sc01455j. eCollection 2023 Jul 5.
Stimuli-responsive polymers can switch specific physical properties in response to a change of the environmental conditions. This behavior offers unique advantages in applications where adaptive materials are needed. To tune the properties of stimuli-responsive polymers, a detailed understanding of the relationship between the applied stimulus and changes in molecular structure as well as the relationship between the latter and macroscopic properties is required, which until now has required laborious methods. Here, we present a straightforward way to investigate the progressing trigger, the change of the chemical composition of the polymer and the macroscopic properties simultaneously. Thereby, the response behavior of the reversible polymer is studied with molecular sensitivity and spatial as well as temporal resolution utilizing Raman micro-spectroscopy. Combined with two-dimensional correlation analysis (2DCOS), this method reveals the stimuli-response on a molecular level and determines the sequence of changes and the diffusion rate inside the polymer. Due to the label-free and non-invasive approach, it is furthermore possible to combine this method with the investigation of macroscopic properties revealing the response of the polymer to the external stimulus on both the molecular and the macroscopic level.
刺激响应性聚合物能够根据环境条件的变化切换特定的物理性质。这种行为在需要自适应材料的应用中具有独特的优势。为了调节刺激响应性聚合物的性质，需要详细了解所施加的刺激与分子结构变化之间的关系以及后者与宏观性质之间的关系，而到目前为止这需要繁琐的方法。在此，我们提出了一种直接的方法来同时研究进展触发因素、聚合物化学成分的变化和宏观性质。由此，利用拉曼显微光谱以分子灵敏度、空间分辨率和时间分辨率研究可逆聚合物的响应行为。结合二维相关分析（2DCOS），该方法揭示了分子水平上的刺激响应，并确定了聚合物内部变化的顺序和扩散速率。由于这种无标记和非侵入性的方法，还可以将该方法与宏观性质的研究相结合，从而揭示聚合物在分子和宏观水平上对外部刺激的响应。
