Open AccessLiquid crystal polymers. IV. Thermotropic polyesters with flexible spacers in the main chain
Author(s) -
Antoun S.,
Lenz R. W.,
Jin J.I.
Publication year - 1981
Publication title -
journal of polymer science: polymer chemistry edition
Language(s) - English
Resource type - Journals
eISSN - 1542-9369
pISSN - 0360-6376
DOI - 10.1002/pol.1981.170190804
Subject(s) - mesogen , thermotropic crystal , mesophase , liquid crystal , polymer , polyester , materials science , substituent , opalescence , crystallography , polymer chemistry , optical microscope , polarized light microscopy , chemistry , organic chemistry , composite material , scanning electron microscope , liquid crystalline , optics , physics , optoelectronics
Two closely related series of polyesters that contain mesogenic units interconnected by flexible spacers along the main chain were prepared and characterized for their liquid crystal properties. All of these polymers showed theotropic behavior, which was examined by DSC, hot‐stage microscopy on a polarizing microscope, small‐angle light and wide‐angle x‐ray scattering methods, and visual observation of stir‐opalescence of the polymer melts. The effect of the length of the flexible spacer and the nature of the substituent, which is on the central aromatic ring of the mesogenic unit, on the stability and molecular order of the mesophase for each of the polymers was investigated and the results are discussed on the basis of the thermodynamic data obtained.