| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1493592 | Optical Materials | 2015 | 6 Pages |
•Azofunctionalized polymer was used as photoalignment layer for liquid crystal.•Poly(esterimide) with side azobenzene derivative substituted with fluorine was applied.•This polymer exhibited high level of photoinduced birefringence and low its relaxation in the dark.•A stronger anchoring of the LC compare to rubbed was obtained.
The custom synthesized azobenzene side-chain poly(esterimide) was used as an aligning material for nematic liquid crystal molecules. The anisotropy of the poly(esterimide) layer was generated by a linearly polarized UV light, as a consequence of multiple trans–cis–trans isomerization cycles. The photoalignment effect was studied by assembling a twisted nematic cell with a proper liquid crystal mixture and geometry to fulfill Mauguin’s limit. The polarizing microscope pictures of the fabricated cells confirmed the twisted arrangement of liquid crystal molecules. The results of electro-optic measurements indicated a stronger anchoring of the liquid crystal molecules by photoaligned poly(esterimide) than that obtained in the case of a rubbed polyimide.
