Dynamics of Rodlike Polymers in Complex Media

9634713 Russo缠结的棒状聚合物将通过扩散测量模型棒在二元溶液中，液晶，三元混合物与其他聚合物，和分散在永久性，非柔性凝胶。所采用的方法包括动态光散射、荧光光漂白恢复和分析超浓缩。 这些研究将阐明分子形状对缠结的影响，缠结是棒状聚合物加工性的重要决定因素。 通过与关于无规飞行聚合物中的缠结的大量文献的比较，可以实现分子刚性的影响。 这项工作还涉及分子复合材料前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。 %该资助福尔斯用于对各种加工环境中的聚合物分子进行分子水平的理解，如溶液、共混物、凝胶等，重点在于刚性杆分子如液晶。 ***

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. ***