Nano-Engineering of New Photoreactive Materials Having Fluorine Units: Synthesis and Photoalignment of Liquid Crystals

Rasha Ata Alaa, Gurumurthy Hegde, Arun M Isloor, Boodappa Chandrakantha, Shridhar Malladi, M.M. Yusoff, Lachezar Komitov

Faculty of Industrial Sciences and Technology, University Malaysia Pahang, 26300, Gambang, Malaysia.
Liquid Crystal Group, Department of Physics, Kemivagen 9, University of Goteborg, Goteborg, Sweden, SE-412 96.
Organic Chemistry Division, De- partment of Chemistry, National Institute of Technology Karnataka, Surathkal, Mangalore-575 025, India.
Syngene International Ltd., Biocon park, plot No 2 & 3, Bommasandra 4th Phase, Jigani Link Rd, Bangalore 560 100.

DOI: 10.4236/snl.2013.31001                

Abstract

In order to investigate the photoalignment mechanism of nematic liquid crystals on an oxadiazoles, new 1,3,4-oxadiazole having fluorine atoms as terminal, as well as sideways was synthesized. Linearly polarized UV light shined in these nano-layered films causes the preferential direction of the liquid crystal molecules either perpendicular (in the case of terminal fluoro substitution) or parallel (in the case of sideways fluorine substitution) to the polarized direction. A powerful indication about the relationship between molecular structure and alignment properties where just by changing fluorine atom can change the entire alignment direction is proposed. Such information is indispensable for the design and synthesis of photoalignment materials for liquid crystal displays of high quality.

Keywords

Liquid Crystals; Fluorine; Parallel; Perpendicular; Irradiation

Conflicts of Interest

The authors declare no conflicts of interest.

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