Materials World Network: In-situ NMR Studies of Processing and Deformation of Polymer/Clay Nanocomposites

纳米复合材料提供了一系列新的材料性能（机械、电学、导电性）。这些特性是由于填料和基体之间的大界面和强相互作用，这是通过专门的加工实现的。将研究用合成氟云母制备聚丙烯或聚对苯二甲酸乙酯纳米复合材料的工艺。流变核磁共振是核磁共振成像和PFG核磁共振的结合，用于局部研究流动模式，提供了对原位加工的深入了解，其中混合过程和对聚合物的排序效应同时进行了研究。关于剪切诱导有序的信息是由剪切下测量的残余偶极耦合提供的，而对分子迁移率的影响是由弛豫时间得出的。剪切速率的局部变化允许研究高局部剪切后聚合物的松弛。由于无机部分含有氟，因此可以高灵敏度地实现界面上的选择性激发，从而可以选择性地研究聚合物与填料的直接相互作用。用氟硅固体核磁共振监测填料本身的插层和分层过程。

Nanocomposites offer a new range of materials properties (mechanical, electrical, permability). These properties result from a large interface and strong interaction between filler and matrix, which is achieved by dedicated processing. The process will be investigated for nanocomposites of poly(propylene) or poly(ethylene terephthalate) with synthetic fluorinated mica. Rheological NMR a combination of NMR imaging, and PFG NMR for the localized investigation of flow pattern provides insight into the processing in situ, where the mixing process and the ordering effects on the polymer are investigated simultaneously. Information about shear-induced ordering is provided by the residual dipolar coupling measured under shear, while the influence on molecular mobility is derived from relaxation times. Local variations in the shear rate permit the investigation of the relaxation of the polymer after high local shear. Since the inorganic part contains fluorine selective excitation across the interface is achieved with high sensitivity permitting the selective investigation of the polymer in direct interaction with the filler. The intercalation and delamination process on filler itself is monitored by fluorine and silicon solid-state NMR.