Dynamics in Interfacial Polymer Systems

技术概述：本研究将集中于确定吸附聚合物体系中分子运动的速率、机制和原因。要了解吸附聚合物的性质，需要了解界面系统的结构和动力学。随着系统规模的减小，界面系统的行为变得更加重要。界面处聚合物体系的性质将使用各种技术来确定，包括核磁共振波谱（NMR），调制差示扫描量热法（MDSC），傅里叶变换红外光谱（FTIR）和其他技术。在可能的情况下，化学/光谱结果将与物理性质研究相关联，例如薄膜附着力的测量。本提案中概述的工作特别感兴趣的是增塑剂对聚合物薄膜的影响，与吸附聚合物中端基相关的动力学，从二氧化硅表面“接枝”的链的行为，吸附共聚物的结构和动力学，以及聚合物纳米复合材料的性质。非技术总结：这项研究将提高在当今高科技世界中重要的关键电子和其他设备和系统的可靠性和实用性。成功开发更强、重量更轻的复合材料可以改进电子设备，如微芯片、传感器和计算机存储器。由于用于制造这些设备的聚合物（如塑料中的长链分子）的许多特性尚不清楚，这些设备的用途可能受到限制，并可能发生严重故障。因此，通过确定这些复杂系统中使用的材料的特性和行为，设备制造商将能够生产出更好、更可靠的设备。此外，该领域培养的学生将增强我国在材料科学重要技术领域的国家竞争力。

TECHNICAL SUMMARY:This research will focus on determining the rates, mechanisms, and causes of molecular motion in adsorbed polymer systems. An understanding of the properties of adsorbed polymers requires knowledge of both the structure and dynamics in interfacial systems. The behavior of the interfacial systems becomes more important as the size of the systems is reduced. The properties of polymer systems at interfaces will be determined using a variety of techniques, including, nuclear magnetic resonance spectroscopy (NMR), and also modulated differential scanning calorimetry (MDSC), Fourier-transform infra-red spectroscopy (FTIR), and other techniques. The chemical/spectroscopic results will be correlated, when possible, to physical property studies, such as the measurement of adhesion in thin films. Of specific interest to the work outlined in this proposal are the effects of plasticizer in polymer films, the dynamics associated with end groups in adsorbed polymers, the behavior of chains "grafted from" silica surfaces, the structure and dynamics of adsorbed copolymers, and the nature of polymer nanocomposites.NON-TECHNICAL SUMMARY:This research will result in improving the reliability and usefulness of critical electronic and other devices and systems that are important in today's high tech world. Successful development of stronger and lighter-weight composite materials can improve electronic devices, such as microchips, sensors, and computer memory. Because many of the properties of polymers (long chain molecules, like those in plastics) used in manufacturing these devices are not understood, the usefulness of these devices may be limited and critical failures possible. Accordingly, by determining properties and behaviors of materials used in these complex systems, device manufacturers will be able to produce better, more reliable devices. In addition, the students trained in this area will enhance our national competitiveness in the important technological area of material science.