Accession Number : ADA186788

Title :   X-Ray Diffraction Study of Thermotropic Liquid Crystalline Polyesters and Diester Model Compounds.

Descriptive Note : Interim technical rept. 28 Aug-1 Oct 87,

Corporate Author : CONNECTICUT UNIV STORRS INST OF MATERIALS SCIENCE

Personal Author(s) : Chin, H H ; Azaroff, L V ; Griffin, A C

PDF Url : ADA186788

Report Date : 01 Oct 1987

Pagination or Media Count : 14

Abstract : Two nematic liquid crystalline polyesters were examined by x ray diffraction following quenching from the nematic temperature in a magnetic field of 15 tesla. It was not possible to quench an aligned nematic glass; instead a polycrystalline phase showing some preferred orientation or an unoriented nematic melts yielded monodomain nematic diffraction patterns with one resembling that of a fiber (crystalline) photograph while the other showed good nematic alignment which could be enhanced slightly by annealing. A series of Siamese-twin diester model compounds also were examined at their respective nematic temperatures in a magnetic field of compounds also were examined a their crystalline phase at room temperature. All displayed well-aligned nematic monodomains above the crystallization point. Keywords: X ray diffraction, Thermotropic liquid crystalline polyesters.

Descriptors :   *ESTERS, *LIQUID CRYSTALS, *POLYCRYSTALLINE, *X RAY DIFFRACTION, ALIGNMENT, ANNEALING, CRYSTALS, DIFFRACTION, GLASS, MAGNETIC FIELDS, MELTS, PATTERNS, SPACE(ROOM), TEMPERATURE

Subject Categories : Organic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE