Polymer, Vol.45, No.12, 4331-4336, 2004
Banded texture of photo-aligned azobenzene-containing side-chain liquid crystalline polymers
Poly(6-[4-(4-cyanophenylazo)phenoxy]x-methylene methacrylate) (P-x, x is 2 or 6) were synthesized and used to study the texture of side-chain liquid crystalline polymers (SCLCPs) after photoinduced orientation. With increasing temperature of irradiated P-2 film UP to 125degreesC, just above its T-g , 123degreesC, a banded texture was observed for SCLCPs under polarized optical microscope (POM). There is no banded texture of irradiated P-6 (T-g, 72degreesC) film when heating to 75degreesC. The formation of the banded texture is considered to be due to co-existing of in-plane and out-of-plane orientation mesogens in P-2 film, which is explained in terms of a molecular model. Based on our experimental results, factors of irradiation light intensity, film thickness, and heating rate on the formation of the banded texture were studied in this work. (C) 2004 Elsevier Ltd. All rights reserved.