Dynamics of Rodlike Polymers in Complex Media

9634713棒状聚合物的Russo纠缠将通过模型棒在二元溶液、液晶、与其他聚合物的三元混合物以及在永久、不灵活的凝胶中的分散体上的扩散测量来研究。采用的方法包括动态光散射法、荧光光漂白回收法和分析超速离心法。这些研究将阐明分子形状对缠结的影响，缠结是棒状聚合物可加工性的重要决定因素。与大量关于无规飞行聚合物中纠缠的文献相比，可以实现分子刚性的影响。这项拟议的工作还涉及分子复合前驱体溶液的性质和聚合物液晶中的各向异性扩散，同时阐明了基质形貌如何控制扩散。%这项资助涉及对各种加工环境中的聚合物分子的分子水平的了解，如溶液、混合物、凝胶等，重点是刚性棒分子，如液晶。***

9634713 Russo Entanglement of rodlike polymers will be investigated by diffusion measurements on model rods in binary solutions, liquid crystals, ternary mixtures with other polymers, and dispersions in permanent, inflexible gels. The methods to be employed include dynamic light scattering, fluorescence photobleaching recovery and analytical ultracentrifugation. These studies will illuminate the effects of molecular shape on entanglement, which is an important determinant of the processibility of rodlike polymers. By comparison to an extensive literature on entanglement in random flight polymers, the effects of molecular rigidity can be realized. This proposed work also bears on the nature of molecular composite precursor solutions and on anisotropic diffusion in polymer liquid crystals, while illuminating how matrix topography governs diffusion. %%% This grant falls in the area of molecular-level understanding of polymer molecules in various processing environments, such as solutions, blends, gels, etc., with emphasis on rigid-rod molecules such as liquid crystals. ***