Photoisomerization Behavior of Smectic Liquid Crystalline AZO Polymers

Abstract We have investigated photoisomerization and photoorientation behavior of a liquid crystalline polymethacrylate bearing p-methoxyazobenzene side groups (C6MeO) and copolymethacrylates with p-alkoxylated azobenzene side chains, (poly(AZO-1) and poly(AZO-2)). Irradiation with linearly polarized visible light generated photoinduced optical anisotropy for all polymers as a result of the reorientation of the azobenzenes toward the direction perpendicular to the electric vector of actinic light. On annealing of the photoirradiated films, the azobenzene chromophores of poly(AZO-1) and poly(AZO-2) showed out-of-plane reorientation, whereas those of C6MeO underwent a marked amplification of in-plane orientation.