Experiments in Polymer Dynamics: Assessment of Theory and Exploration of Properties

各种强大的实验技术(振荡流动双折射、振荡电双折射、动态光散射、强迫瑞利散射、小角中子散射、总强度光散射和脉冲场梯度核磁共振)将被用来为至少一个聚合物/溶剂体系提供独特详细和全面的数据集。无限稀释特性(包括线圈半径、平移扩散系数、特性粘度、最长松弛时间和松弛时间谱)将与现有的最佳理论进行比较。所有这些性质的同时比较将允许对分子模型的强度进行最严格的测试，特别是评估参数值的物理意义。除了上面列出的长波特性外，还将测量聚合物和溶剂可用的局部松弛模式。这将阐明聚合物溶液迄今尚未解释的高频动力学性质，并提供第一次对局部聚合物运动模型的系统测试。最终目标包括开发增强聚合物表征的技术和阐明聚合物结构-性能关系。

A variety of powerful experimental techniques (oscillatory flow birefringence, oscillatory electric birefringence, dynamic light scattering, forced Rayleigh scattering, small-angle neutron scattering, total intensity light scattering, and pulsed field gradient NMR) will be employed to provide a uniquely detailed and comprehensive data set for at least one polymer/solvent system. Infinite-dilution properties (including coil radius, translational diffusion coefficient, intrinsic viscosity, longest relaxation time, and relaxation-time spectrum) will be compared with the best available theories. Simultaneous comparison of all these properties will permit the most rigorous test of the strengths of molecular models, and in particular, evaluate the physical significance of parameter values. In addition to the long-wavelength properties listed above, measurements of the local modes of relaxation available to the polymer and to the solvent will be made. This will shed light on the hitherto unexplained high-frequency dynamics properties of polymer solutions, and provide the first systematic test of models for local polymer motions. The ultimate goals include the development of techniques for enhanced polymer characterization and the elucidation of polymer structure-property relationships.