Hostname: page-component-7479d7b7d-fwgfc Total loading time: 0 Render date: 2024-07-13T00:17:39.105Z Has data issue: false hasContentIssue false
  • English
  • Français

Photoactive Cholesteric Polymeric Material With Dual Photochromism

Published online by Cambridge University Press:  15 March 2011

Alexey Bobrovsky ,
Natalia Boiko  and
Valery Shibaev
Alexey Bobrovsky
Affiliation:
Department of Chemistry, Moscow State University, Lenin Hills, 119899 Moscow, Russia
Natalia Boiko
Affiliation:
Department of Chemistry, Moscow State University, Lenin Hills, 119899 Moscow, Russia
Valery Shibaev
Affiliation:
Department of Chemistry, Moscow State University, Lenin Hills, 119899 Moscow, Russia
Get access

Abstract

New cholesteric polymeric material containing a liquid crystalline (LC) copolymer with side phenylbenzoate nematogenic and photochromic spiropyran groups and 5 mol % chiral photochromic dopant based on cinnamic acid and isosorbide was prepared. It was shown that UV irradiation and subsequent annealing of planarly-oriented mixture films lead to untwisting of the cholesteric helix and cause an irreversible shift of selective light reflection to the long-wavelength region. This process is explained by the E-Z isomerization of chiral photochromic groups of the dopant relative to a C=C bond accompanied by a decrease in their twisting ability. Upon UV irradiation of films at room temperature, a thermally reversible transformation of spiropyran groups into a merocyanine form takes place, which is followed by the appearance of an intense absorption maximum in the visible spectral region. It was shown, that the use of the material prepared in this work provides an opportunity to record two images at a time: one image is due to a change in the helical pitch and another image (above) is due to the photochromism of spiropyran groups. It is pertinent to note that using the approach developed in this work allows one to widely vary the range of materials exhibiting dual photochromism. It was demonstrated that the mixture under examination shows promise as new photosensitive material for optics, optoelectronics, and data recording.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 709: Symposium CC – Advances in Liquid Crystalline Materials and Technologies , 2001 , CC5.6.1
Copyright
Copyright © Materials Research Society 2002

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Applied Photochromic Polymer Systems, ed McArdle, C.B. (Blackie, 1992).Google Scholar
2. Polymers as Electrooptical and Photooptical Active Media, ed. Shibaev, V. P. (Springer-Verlag, 1996) p. 37.Google Scholar
3. Shibaev, V. P., Int. J. Polym. Mater. 45, 533 (2000).Google Scholar
4. Bobrovsky, A. Yu., Boiko, N. I., and Shibaev, V. P., Polymer Science, Ser. A 40, 232 (1998).Google Scholar
5. Witte, P. Van de, Galan, J. C., and Lub, J., Liq. Cryst. 24, 819 (1998).Google Scholar
6. Bobrovsky, A. Yu., Boiko, N. I., and Shibaev, V. P., Liq. Cryst. 25, 679 (1998).Google Scholar
7. Bobrovsky, A. Yu., Boiko, N. I., and Shibaev, V. P., Liq. Cryst. 12, 1749 (1999).Google Scholar
8. Witte, P. Van de, Neuteboom, E. E., Brehmer, M., J. and Lub, J. Appl. Phys. 85, 7517 (1999).Google Scholar
9. Bobrovsky, A. Yu., Boiko, N. I., Shibaev, V. P., and Springer, J., Adv. Mater. 12, 1180 (2000).Google Scholar
10. Bobrovsky, A. Yu., Boiko, N. I., Shibaev, V. P., and Springer, J., Liq. Cryst. 28, 919 (2001).Google Scholar
11. Bobrovsky, A. Yu., Boiko, N. I., and Shibaev, V. P., Liq. Cryst. 27, 57 (2000).Google Scholar
12. Bobrovsky, A. Yu., Boiko, N. I., and Shibaev, V. P., Polymer Science, Ser. A 42, 38 (2000).Google Scholar
13. Bobrovsky, A. Yu., Boiko, N. I., Shibaev, V. P., Kalik, M. A., and Krayushkin, M. M., J. Mater. Chem. 11, 2004 (2001).Google Scholar
14. Bobrovsky, A. Yu., Boiko, N. I., and Shibaev, V. P., Mol. Cryst. Liq. Cryst. 363, 35 (2001).Google Scholar
15. Boiko, N. I., PhD Thesis, (Moscow State University, 1987).Google Scholar
16. Kurien, K C., J. Chem. Soc. B 2081 (1971).Google Scholar