Dynamics in Interfacial Polymer Systems

技术综述：这项研究将集中在确定吸附聚合物系统中分子运动的速率、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知识。随着系统尺寸的减小，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(核磁共振)、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。这项建议中概述的工作特别令人感兴趣的是增塑剂在聚合物薄膜中的作用，与吸附聚合物中端基相关的动力学，从硅胶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。非技术摘要：这项研究将导致提高关键电子和其他设备和系统的可靠性和可用性，这些设备和系统在当今高科技世界是重要的。成功开发更坚固和更轻的复合材料可以改进电子设备，如微芯片、传感器和计算机内存。由于用于制造这些设备的聚合物(长链分子，如塑料中的那些)的许多特性尚不清楚，因此这些设备的用途可能会受到限制，并可能出现严重的故障。因此，通过确定这些复杂系统中使用的材料的性能和行为，设备制造商将能够生产更好、更可靠的设备。此外，在这一领域培养的学生将增强我们在材料科学这一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.