Rheological and Magnetic Field Effects on Ordering Transitions in Thermotropic Liquid Crystalline Polymers

流变学和磁场对热致液晶聚合物有序转变的影响

• 批准号: 9422180
• 负责人: H. Henning Winter
• 金额: $ 42万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-05-01 至 2000-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9422180&HistoricalAwards=false
• 关键词: Rheological; Magnetic; Field; Effects; Ordering

9422180 Winter The proposed research has the objectives of (1) organizing macromolecules into highly ordered structures and (2) studying the effects of flow and phase transitions on this order. For that purpose, we chose liquid crystalline polymers because of their extended chain conformation and their crystal like optical properties which allow direct observation of the phenomena. The experimental methods will mostly be rheometry and polarizing microscopy (conoscopy). %%% The lack of understanding of the behavior during processing has prevented the widespread use of engineering plastics which have been synthesized in abundance in recent years. Emphasis is on morphology development by physical processes rather than chemical processes since the end-use properties are as much determined by processing (which needs to be advanced) as by the chemistry of the polymers. The proposed research will help to find processing strategies which utilize phase transitions to organize polymers into novel morphologies with superior properties. ***

9422180冬季拟议的研究目标是(1)将大分子组织成高度有序的结构，(2)研究流动和相变对这种有序结构的影响。为此，我们选择了液晶聚合物，因为它们的延伸链构象和类似晶体的光学性质允许直接观察到这一现象。实验方法主要是流变学和偏光显微镜(结肠镜)。由于缺乏对加工过程中行为的了解，阻碍了近年来大量合成的工程塑料的广泛使用。重点是通过物理过程而不是化学过程来发展形态，因为最终用途的性质既取决于聚合物的化学成分，也取决于加工过程(需要改进)。所提出的研究将有助于找到利用相变将聚合物组织成具有优异性能的新形态的加工策略。***