Journal article
Homeotropic Alignment of a Discotic Liquid Crystal Induced by a Sacrificial Layer
Laboratoire de chimie des polymères, Université Libre de Bruxelles, CP 206/1, Boulevard du Triomphe, B-1050 Bruxelles, Belgium, Laboratory for Chemistry of Novel Materials, Université de Mons-Hainaut/Materia Nova, 20 Place du Parc, B-7000 Mons, Belgium, Risø National Laboratory for Sustainable Energy, Technical University of Denmark P.O. Box 49, 4000 Roskilde, Denmark
A convenient method to induce face-on orientation of an alkoxy phtalocyanine discotic mesogen is described. The alignment is imposed by the confinement of the discotic thin films with a top sacrificial polymer layer that is easily removed by washing with a selective solvent, after thermal annealing.
Thin films have been characterized by optical and atomic force microscopy, UV-Vis absorption spectroscopy, and grazing incidence wide angle X-ray scattering. The data converge in showing the central role of the sacrificial layer in promoting alignment with the planar molecules orienting parallel to the substrate in an essentially homeotropic arrangement over large lateral length scales and the persistence of this desirable alignment after removal of the layer.
Language: | English |
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Publisher: | American Chemical Society |
Year: | 2009 |
Pages: | 14398-14406 |
ISSN: | 19327455 and 19327447 |
Types: | Journal article |
DOI: | 10.1021/jp9035343 |