УДК: 535.514, 532.783, 535.36

Polarizing properties of a stretched film of a polymer-dispersed liquid crystal with a surfactant dopant

Egamov, M.K., Gerasimov, V.P., Krakhalev, M.N., Prishchepa, O.O., Loiko, V.A., Zyryanov, V.Y.

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

Эгамов М.Х., Герасимов В.П., Крахалев М.Н., Прищепа О.О., Лойко В.А., Зырянов В.Я. Поляризующие свойства вытянутой пленки капсулированного полимером жидкого кристалла с примесью сурфактанта // Оптический журнал. 2014. Т. 81. № 7. С. 67–71.

Egamov M.Kh., Gerasimov V.P., Krakhalev M.N., Prishchepa O.O., Loiko V.A., Zyryanov V.Ya. Polarizing properties of a stretched film of a polymer-dispersed liquid crystal with a surfactant dopant [in Russian] // Opticheskii Zhurnal. 2014. V. 81. № 7. P. 67–71.

For citation (Journal of Optical Technology):

M. H. Egamov, V. P. Gerasimov, M. N. Krakhalev, O. O. Prishchepa, V. Ya. Zyryanov, and V. A. Loiko, "Polarizing properties of a stretched film of a polymer-dispersed liquid crystal with a surfactant dopant," Journal of Optical Technology. 81(7), 414-417 (2014). https://doi.org/10.1364/JOT.81.000414

Abstract:

The transmittance anisotropy of a composite polymer–liquid-crystal film has been studied as it varies with the degree to which it is elongated. The composite film includes polyvinyl alcohol, the nematic liquid crystal 4-n-pentyl-4′-cyanobiphenyl, and the surfeiting cetyltrimethylammonium bromide, which initiates homeotropic adhesion of the nematic to the surface of the polymer. It is shown that, when the film is uniaxially stretched, the transmittance of the orthogonally polarized component of directly transmitted radiation and accordingly the degree of polarization abruptly increase, reaching saturation when it is stretched to twice its length. Such variation of the film’s macroscopic optical properties can be caused by an orientational–structural transition to a homogeneous configuration of the director in deformed droplets of the nematic and makes it possible to substantially improve the optical characteristics of light polarizers based on such composite media.

Keywords:

optical anisotropy, light polarization, polymer-dispersed liquid crystal, configuration of the director, surfactant, light scattering

Acknowledgements:

This work was carried out with the partial support of Grant 12-03-00816 of the Russian Foundation for Basic Research, Grants 24.32 and 24.29 of the Presidium of the Russian Academy of Sciences, and joint project 30 of the Siberian Section of the Russian Academy of Sciences (SO RAN), and a joint project of the SO RAN and the National Scientific Council of Taiwan.

OCIS codes: 260.5430, 160.3710

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