This award is for the renewal of the Materials Research Group at Case Western Reserve University (Grant of structure, dynamics, and transitions of liquid crystalline polymers. The primary goal of the research by the group is to understand the physical and chemical requirements for generation of crystalline structures containing fully extended chains from neumatic columnar hexagonal phases and copolymers containing these phases. The research emphasis is on synthesis of polymers, having controlled molecular structure, which are predicted to have neumatic of columnar phases, with focus on main chain polyesters and polyethers in which asymmetric mesogens are linked by flexible spacers. The work also includes synthesis of supramolecular self- assembling polymers designed to have cylindrical conformations, preparation and characterization of micro-phase-separated supramolecular assemblies, based on block co-polymers that contain different mesomorphic and glassy segments. The structure and dynamics of these polymers is being determined by x-ray and neutron scattering, static and dynamic light scattering, fluorescence energy transfer spectroscopy, and nuclear magnetic resonance spectroscopy. The electronic, magnetic, optical, and dielectric properties are also being determined. Theoretical analyses of the molecular assembly, dynamics, phase transitions, rheology and other physical properties of the mesophases is also being done in parallel with the experimental effort.
