Photoinduced thermal alignment of a photoreactive polymer liquid crystal

Abstract

We describe the synthesis of a new photoreactive polymer liquid crystal (PLC) and alighment of the PLC film induced by linearly polarized (LP) UV irradiation and thermal treatment. The synthesized PLC showed nematic phase. When the irradiation time was short, the photoinduced negative dichroism was enhanced in a direction perpendicular to the electric vector E of the LP-UV light after annealing at 130℃. On the other hand, the alignment direction changed parallel to E of the LP-UV light when the irradiation time was long.