Light Scattering, Rheo-Optical, and Rheological Studies on Concentrated Polymer Solutions

浓聚合物溶液的光散射、流变光学和流变学研究

• 批准号: 9112726
• 负责人: Guy Berry
• 金额: $ 30万
• 依托单位: Carnegie-Mellon University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-08-15 至 1995-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9112726&HistoricalAwards=false
• 关键词: Light; Scattering; Rheo; Optical; Rheological

This study comprises four distinct areas of investigation: (1) Static and dynamic light scattering on aligned nematic solutions of a rodlike polymer, and rheological and rheo-optical studies on aligned and unaligned nematic solutions of the same solutions; (2) Similar studies on the nematic phase of a thermotropic copolymer, as a function of temperature; (3) Static and dynamic light scattering, and rheological studies on moderately concentrated solutions of polystyrene in decalin; and (4) Static and dynamic light scattering on dilute solutions of polymers prone to intermolecular association. In the first study, the Leslie viscosities, the Frank curvature elasticities, and the order parameter will be determined over a range of chain length and polymer concentration. These parameters will also be used in the analysis of nonlinear rheological behavior in fast flow behavior. In the second, a preliminary study will be undertaken to evaluate the feasibility of the scattering studies to determine certain Leslie viscosities and Frank elasticities on a solvent-free aligned nematic polymer. In the third, the thermodynamics and chain dynamics will be studied over a range of conditions, from the Flory Theta state to "good solvent" conditions. The appearance of relaxation in the dynamic scattering due to chain entanglements will be of special interest. Finally, in the fourth, the possibility that certain thermochromic effects in dilute solution are linked to (metastable) intermolecular association will be investigated. This research aims to clarify the solution behavior of various types of important polymers, especially those able to form liquid crystals.

本研究包括四个不同的调查领域：（1） 静态和动态光散射在排列的双折射溶液 棒状聚合物，流变学和流变光学研究 相同解的对齐和未对齐的双解;（2） 对热致共聚物的双相的类似研究， （3）静态和动态光 散射和流变学研究 聚苯乙烯在十氢萘中的溶液;以及（4）静态和动态 在聚合物稀溶液上的光散射 分子间缔合 在第一项研究中， 粘度，弗兰克曲率弹性，和顺序 参数将在链长范围内确定， 聚合物浓度 这些参数也将用于 快速流动行为中的非线性流变行为分析。 第二，将进行初步研究， 散射研究的可行性，以确定某些 无溶剂取向膜的Leslie粘度和Frank弹性 聚合物。 第三，热力学和链 动力学将在一系列条件下进行研究，从弗洛里 Theta状态为“良好溶剂”条件。 的外观 由于链缠结引起的动态散射中的弛豫 会引起特别的兴趣。 最后，在第四， 稀溶液中某些热致变色效应 连接到（亚稳态）分子间缔合将是 研究了 本研究的目的是澄清各种溶液行为 重要的聚合物类型，特别是那些能够形成液体的聚合物 晶体