Segmental Dynamics in Ultra-thin Polymer layers

该提案要求资金用于继续研究聚合物在固体界面上的节段运动。由于界面区域相当薄，因此需要光谱技术来表征它们。在这种情况下，要使用的技术主要是核磁共振（NMR）。核磁共振研究将用氘和特殊标记的聚合物进行。氘核磁共振有几个优点，聚合物将通过线形、二维交换和弛豫时间研究来研究。这将给出聚合物分子在界面处运动的图像。特别令人感兴趣的是用氘交换实验对分子运动的量化。氘标签的使用也可以提供对比，以便即使在存在未标记聚合物的覆盖层的情况下也可以研究界面。成功完成这项工作的结果将是界面材料的结构和动力学知识将帮助研究人员设计具有增强性能的界面系统，用于先进的复合材料结构，电子设备和粒子稳定等先进应用。由聚合物制成的薄膜在包括结构复合材料、传感器和电子产品在内的各种应用中都很重要。在这些系统中，薄膜的性能对使用它们的设备的成功至关重要。聚合物性质的表征对于理解器件的工作原理至关重要。最终，如果了解聚合物的行为和作用，可以改善聚合物器件的性能。随着设备的尺寸和聚合物薄膜的厚度变小，这些决定变得更加重要。例如，在电子器件中，聚合物层的一些特性随着聚合物层的厚度而改变。

This proposal requests funds for continuation of studies of the segmental motion of polymers at solid interfaces. Since the interfacial regions are quite thin, spectroscopic techniques are required for their characterization. In this case, the technique to be used is primarily nuclear magnetic resonance (NMR). The NMR studies will be done with deuterium and specifically labeled polymers. Deuterium NMR has several advantages and the polymers will be studied with line shape, two-dimensional exchange, and relaxation time studies. These will give a picture of the motion of the polymer molecules at the interface. Of particular interest is the quantification of the molecular motion with the deuterium exchange experiment. The use of the deuterium label can also provide contrast so that the interface can be studied even in the presence of an overlayer of unlabeled polymers. The result of the successful completion of this work will be that knowledge of the structure and dynamics of interfacial materials will help researchers to design interfacial systems with enhanced properties for advance applications such as advanced composite structures, electronic devices, and particle stabilization.%%%Thin films made from polymers are important in a variety of applications including structural composites, sensors, and electronics. In these systems, the properties of the thin films are critical to the success of the devices that use them. Characterization of the properties of the polymers is crucial to an understanding of how the devices work. Ultimately, the properties of devices with polymers can be improved if the behavior and their roles are understood. These determinations become even more crucial as the size of the devices, and hence the thickness of the polymer films become smaller. For example, in electronic devices, some of the properties of the polymer layers change with the thickness of the polymer layer.