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Relaxation processes in oriented liquid crystalline polymers
Author(s) -
Ward I.M.
Publication year - 1993
Publication title -
makromolekulare chemie. macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 0258-0322
DOI - 10.1002/masy.19930690110
Subject(s) - thermotropic crystal , polymer , materials science , relaxation (psychology) , perpendicular , polyester , monomer , hydroxybenzoic acid , dielectric , liquid crystalline , shear (geology) , polymer chemistry , chemical physics , composite material , chemistry , organic chemistry , geometry , psychology , social psychology , mathematics , optoelectronics
A review is presented of research on oriented thermotropic liquid crystalline polymers undertaken at Leeds University. A range of main‐chain polyesters has been studied based on 1,4‐hydroxybenzoic acid and 2,6‐hydroxynaphthoic acid as the primary monomers. By using a combination of dynamic mechanical, dielectric and NMR measurements insight has been gained into the molecular motions associated with the three principal relaxation processes. The behaviour in tension, for stresses parallel and perpendicular to the principal orientation direction, has been related to that in shear by use of mechanical models.