基于二维相关光谱的多维分子光谱技术是近些年发展起来的先进光谱分析手段，特别适合于在分子水平上研究各种外扰作用下的物理化学体系的结构变化.本文就二维相关光谱及其衍生的外扰相关移动窗口技术对温敏水溶性聚合物体系尤其是LCST型聚合物体系的研究进展进行了综述.LCST型聚合物水溶液在LCST（低临界溶解温度）变化前后会发生线团－胶束的分子链构象变化，而在凝胶体系内则表现为体积的塌缩与溶胀.红外光谱可以很好地跟踪这一温度变化的过程，而一维及二维相关光谱分析可以方便地确定相转变温度、转变温度区间、响应程度及各基团的响应次序，非常有助于诠释温敏聚合物体系的响应机制.本文综述了二维相关光谱分析在LCST型均聚物、共聚物和共混物、凝胶以及聚合物刷体系中的典型应用.%Two-dimensional spectral analysis based on two-dimensional correlation spectroscopy has been proved to be a very powerful tool to study the structural changes of various physical-chemical systems at the molecular level. This review summarize the recent research progress of two-dimensional correlation spectroscopy and its derivative technique, perturbation correlation moving window, in the investigation of thermoresponsive water-soluble polymers, especially LCST (lower critical solution temperature)-type polymers. Around LCST, LCST-type polymers in aqueous solutions undergo coil-to-globule conformational changes while in gel, volume phase transitions LCST-type polymers exhibit collapsing and swelling, which can be well traced by in-situ IR spectroscopy. Based on dynamic IR spectra, the combined one- and two-dimensional correlation spectroscopy analysis can be used to easily determine the transition temperature, transition temperature range, temperature-responsiveness, and the sequence order of different species, which are very helpful to illustrate the whole transition process. In this review, we will mainly emphasize on the typical applications of two-dimensional correlation spectroscopy analysis in the systems of LCST-type homopolymers, copolymers and mixtures, gels, and polymer brushes.
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