Novel applications of thermotropic liquid crystalline polymers (TLCP) are currently prevented by the lack of understanding of the structure formation processes in the liquid crystalline state and during solidification (transition to the crystal state). Such understanding is required for controlling mechanical, electrical, and optical properties which not only depend on the intrinsic molecular properties but also on the large-scale texture. This research involves a cooperative study of the structuring of TLCPs in rheological and magnetic fields. Light scattering and microscopy (R.S. Stein) and rheology (H.H. Winter) will be applied to specifically synthesized samples (Polaroid) and the magnetic field of a laboratory will be utilized to create the necessary alignment. Intermediate textural states will be produced by applying well-defined mechanical and electrical fields. The study of the field induced monodomain will give the intrinsic properties (Miesowicz viscosities, Frank elastic constants) which are needed to understand the behavior of polydomains. The natural polydomain and intermediate disclination densities will be studied to lay the foundation for practical applications (design of suitable processing equipment) as well as for a theoretical description of polydomain TLCPs.

Agency
National Science Foundation (NSF)
Institute
Division of Materials Research (DMR)
Application #
9101323
Program Officer
David Nelson
Project Start
Project End
Budget Start
1991-08-01
Budget End
1995-01-31
Support Year
Fiscal Year
1991
Total Cost
$370,600
Indirect Cost
Name
University of Massachusetts Amherst
Department
Type
DUNS #
City
Amherst
State
MA
Country
United States
Zip Code
01003