Polymer Dynamics at Interfaces and in Complex Environments

本研究聚焦于高分子物理的一个核心问题。聚合物如何沿着固液界面和受限几何结构扩散。这将使用新的荧光光谱实验平台进行研究，有时使用单分子分辨率（FCS，荧光相关光谱），有时使用FRAP（光漂白后荧光恢复），有时使用FRET （Förster共振能量转移），有时使用单粒子成像。一旦实现，这些实验将产生空间分辨率为0.5 m的空间分辨测量结果。研究将集中在聚合物界面的一侧？聚合物平移扩散对链长、聚合物表面覆盖率的依赖，以及在受限聚合物熔体的情况下，对薄膜厚度的依赖——试图理解这个问题的普遍方面。智力上的优点是对聚合物如何在表面和受限几何中扩散的新理解，这是许多科学和技术应用的基础，包括粘附，相互扩散，摩擦，复合材料和纳米复合材料的机械行为，以及其他种类的功能特性，以及开发新的实验工具来量化聚合物在超薄膜中的迁移性，这是传统方法无法表征的。研究生将与其他来自化学、化学工程、物理和材料科学的学生组成一个跨学科研究小组，将研究和教育结合起来。本研究寻求对聚合物和塑料如何在表面和受限几何形状中移动的新的基本理解。高分子科学亟待解决的问题之一，它的解决将为粘附、摩擦、复合材料和纳米复合材料、功能材料等领域的技术应用和技术改进打开大门。这项研究将产生新的实验工具来量化聚合物迁移率，这是传统方法无法表征的。这将改善聚合物领域的研究基础设施。该实验室在多样性方面有着良好的记录，特别是在涉及女性本科生和研究生研究人员以及将研究与教育相结合方面。这项研究的广泛影响包括与工业界、国际合作者的紧密联系，以及促进教育多样性。

TECHNICAL SUMMARY This research focuses on a central problem of polymer physics ? how polymers diffuse along the solid-liquid interface and in confined geometries. This will be studied using novel experimental platforms of fluorescence spectroscopy, sometimes with single-molecule resolution (FCS, fluorescence correlation spectroscopy), sometimes with FRAP (fluorescence recovery after photobleaching), sometimes with FRET (Förster resonance energy transfer), sometimes with single-particle imaging. As implemented, these experiments will yield spatially-resolved measurements with spatial resolution 0.5 μm. The research will focus on the polymer side of the interface ? the dependence of polymer translational diffusion on chain length, polymer surface coverage, and in the case of confined polymer melts, on film thickness -- seeking to understand the universal aspects of this problem. The intellectual merit is to develop new understanding of how polymers diffuse at surfaces and in confined geometries, which is fundamental in many scientific and technical applications, including adhesion, interdiffusion, friction, the mechanical behavior of composite and nanocomposite materials, and functional properties of other kinds, and also to develop new experimental tools to quantify polymer mobility in ultra-thin films that are impossible to characterize by conventional methods. The graduate students will be part of an interdisciplinary research group with other students from chemistry, chemical engineering, physics, and materials science, integrating research and education. NON-TECHNICAL SUMMARYThis research seeks new fundamental understanding of how polymers and plastics move about at surfaces and in confined geometries. One of the most pressing unsolved problems of polymer science, to solve it will open the door to technical applications and technological improvement in areas including adhesion, friction, composite and nanocomposite materials, and functional materials. This research will produce new experimental tools to quantify polymer mobility impossible to characterize by conventional methods. This will improve research infrastructure in the polymer field. This laboratory has an excellent track record regarding diversity, especially in involving women undergraduate and graduate researchers, and integrating research with education. The broader impact of this research involves strong connections with industry, with international collaborators, and the promotion of educational diversity.