THE LEVICH INSTITUTE ANNOUNCES THE FOLLOWING SEMINAR

Tuesday, 10/03/2000 4:00 PM Steinman Hall, Room #1M-22 Professor Patrick Mather Institute of Materials Science and Chemical Engineering Department University of Connecticut "Optical Microrheology of Segmented Thermotropic Polymers"

ABSTRACT

Thermotropic polymers are those thermoplastics that feature quiescent orientational ordering in the molten state. Flows of such polymers have been studied since their discovery about twenty years ago; however, a unified description of the many complex phenomena has remained elusive. We have been applying novel optical rheometry methods to model thermotropic polymers in order to reveal the interplay between liquid crystalline microstructure and applied shearing flow. In this seminar, I will first describe the experimental methods used and then discuss our observations for two types of phenomena; namely, (i) evidence for a flow-induced isotropic-to-nematic phase transition and (ii) orientational response to a flow reversal. Finally, I will discuss unsolved problems in the flow of thermotropic polymers and propose collaborative approaches toward a refined understanding of this important problem.

BRIEF ACADEMIC/EMPLOYMENT HISTORY:

• University of Connecticut 7/99 – present, Assistant Professor, Polymer Program, Institute of Materials Science; Chemical Engineering
• Air Force Research Laboratory 4/97-7/99 Leader, Polymer Processing Group - Materials Directorate, Polymer Branch.
• The University of Utah 7/97-7/99 Adjunct Faculty - Department of Mechanical Engineering.
• USAF Phillips Laboratory 4/94-3/97 Materials Research Engineer - Propulsion Sciences Division.
• University of California, Santa Barbara 9/90-4/94 Research Assistant and Teaching Assistant

RECENT RESEARCH INTERESTS

• Defect Dynamics in Liquid Crystalline Materials for Structural and Optical Applications (thermotropic LCPs, nematic, smectic, and cholesteric LCs).
• Simultaneous Experimental Methods: Flow-Microscopy, Flow-SALS, Flow-SAXS/WAXS.
• Structure Property Relationships in Inorganic-Organic Hybrid Thermoplastics and Nanocomposites.
• New Functional Polymers, Mechanisms, and Devices based on Shape-Memory Effect.

Return to Fall, 2000 Seminar Schedule