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

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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. ***