Name : 23rd Symposium on Liquid Crystals
Number : 23
Location : [in Japanese]
Date : September 25, 1997 - September 27, 1997
We synthesized methacrylate copolymers comprizing 2-cinnamoylethozy-4-biphenyloxyhexyl group and 4-cyanobiphenyloxyhexyl group. All synthesized copolymers showed a liquid crystallinity and can be photo-crosslink by UV irradiation. Linearly polarized (LP) UV irradaition on the eopolymer films resulted in an optical anisotropy of the film, especially at the LC temperature of the copolymers. The optical anisotropy were investigated by polarized UV and FT-IR measurements. The direction of the orientation of the mesogenic group was found to be parallel to the electrical direction of the incident LP-UV light. The reorientation of the non-reacted mesogenic group is occur during the LP-UV photoreaction. The induced birefringence Δn is in the range of 0.02-0.07. Because of the high photo-crosslinking, the LP-UV photoreacted film shows the orientational stability.