ISSN:
0323-7648
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Infrared spectroscopy is used to study the influence of the polarization of the irradiating light and the substrate surface treated with polyimide on the reorientation process of dye-containing liquid-crystalline side-group copolymers. The depolarization of the linearly polarized light on brushed polyimide surfaces affects the reorientation process and as a consequence the irradiation direction becomes the new order axis after irradiation. Relaxation processes are observed after short irradiation times, since a new stable equilibrium state has not been reached. In contrast, complete reorientation, achieving changes in order parameter of 0.9, is observed after long irradiation times. The system is then stabilized in the new orientational distribution and no relaxation processes occur. The relaxation processes can be explained by a combination of matrix response and thermal cis-trans back relaxation of the azobenzene.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/actp.1996.010470105
