Polymer dynamics in solid-state matrices studied by field-cycling NMR

通过场循环核磁共振研究固态基质中的聚合物动力学

• 批准号: 196288109
• 负责人: Professor Dr. Ernst Rößler
• 金额: --
• 依托单位: Lehrstuhl für Experimentalphysik II (Optoelektronik weicher Materie)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/196288109?language=en
• 关键词: Polymer; dynamics; solid; state; matrices

The aim of the proposal is to characterise the local glassy dynamics as well as the collective dynamics of polymers embedded in solid-state matrices (nanoconfinement of different sizes) by means of different nuclear magnetic resonance (NMR) methods. Special focus is given on applying electronic (fast) field-cycling (FFC) 1H NMR which is particularly suited for probing the slow polymer dynamics. Selected solid-state 1H and 2H NMR will complement the studies. FFC NMR investigations have shown for certain polymers that the collective dynamics are significantly changed with respect to their bulk behaviour when they are embedded in a confinement ranging from 60 nm – 1000 nm, a length scale much larger than the size of a polymer in the melt. So far this so called corset effect is not well understood – and a disputed phenomenon, as other experiments have challenged these results. Thus, the proposal is devoted to experimentally validating and promoting the understanding of the corset effect. We study the interplay of glassy and polymer dynamics in different porous systems with pores sizes in the range of 5 nm up to 1000 nm.

该提案的目的是通过不同的核磁共振（NMR）方法来研究嵌入固态基质（不同尺寸的纳米限制）中的聚合物的局部玻璃态动力学和集体动力学。特别关注的是应用电子（快）场循环（FFC）1H NMR，这是特别适合于探测缓慢的聚合物动力学。选定的固态1H和2 H NMR将补充研究。FFC NMR研究表明，某些聚合物的集体动力学显着改变，相对于它们的整体行为时，他们被嵌入在一个限制范围从60 nm - 1000 nm，长度尺度远大于聚合物在熔体中的尺寸。到目前为止，这种所谓的紧身胸衣效应还没有得到很好的理解-而且是一个有争议的现象，因为其他实验已经挑战了这些结果。因此，该提案致力于实验验证和促进对紧身胸衣效应的理解。我们研究了在不同的多孔系统中的玻璃和聚合物动力学的相互作用，孔径在5 nm至1000 nm的范围内。