Azobenzene-containing LC polymethacrylates highly photosensitive in broad spectral range

0463228 - FZÚ 2017 RIV US eng J - Journal Article
Bobrovsky, A. - Shibaev, V. - Cigl, Martin - Hamplová, Věra - Pociecha, D. - Bubnov, Alexej
Azobenzene-containing LC polymethacrylates highly photosensitive in broad spectral range.
Journal of Polymer Science. Part A - Polymer Chemistry. Roč. 54, č. 18 (2016), s. 2962-2970. ISSN 0887-624X. E-ISSN 1099-0518
R&D Projects: GA ČR GA16-12150S; GA MŠMT(CZ) LH15305
Institutional support: RVO:68378271
Keywords : liquid crystals * polymethacrylate * photosensitive * azo group * smectic A * photo-optical properties
Subject RIV: CD - Macromolecular Chemistry
Impact factor: 2.952, year: 2016

Two photosensitive chiral liquid crystalline (LC) azobenzene-containing polymethacrylates having different length of flexible spacer connecting chromophores with backbone spacer were synthesized and their phase behaviour and photo-optical properties were studied. It is shown, that smectic phase (SmA*) formation in films of polymer with longer spacer predetermines quite its unusual spectral response to UV and subsequent visible light actions. The SmA* phase promotes spontaneous homeotropic alignment of azobenzene chromophores in polymer films. UV-irradiation induces not only E-Z isomerization, but also results in disruption of homeotropic alignment, whereas subsequent visible light action enables to obtain films with the low degree of chromophores orientation. The possibility of using red polarized light of moderate intensity for optical photo-recording on polymer films is demonstrated.
Permanent Link: http://hdl.handle.net/11104/0262659