The precursor polymer PI-OH was pmpared by the polycondension of bisphenol-A diamine monomer (BISDA) and a dianhydfide monomer (6FDA) in solution Then cinnamoyl chloride was reacted with the hydroxyl-containing precursor to prepare the photosensitive polymer PI-CI with einnamate pendant groups The polymers were characterized by FTIR

1H-NMR and differential scanning calorimetry (DSC) The photochemical properties of PI-CI were studied by using UV-Vis and FTIR The polymer showed significant photodichmism upon UV irradiation due to the photodimefization After processed by Linear Polarized Polymerization (LPP)

the spin-coated fihns of PI-CI wee used as photo-alignment layers to assemble sandwich-type liquid crystal cells via a capillary action using a nematie liquid crystal 5CB The observation by polarized microscope showed that the PI-CI photo-alignment layem had the ability to align LC molecules in a very uniform way．The photosensitive polymer PI-CI of bisphenol-A is promising for the application as photo-alignment layer for liquid crystal displays.