An acrylate-based azo monomer 4-[N-(2-acryloyloxyethyl)-N-ethylamino]-4′-nitro-azobenzene(ANB) was synthesized and grafted to surfaces of PET films by solid-phase graft polymerization using benzophenone as UV photoinitiator．Thus grafted films with photoresponsive surfaces were obtained．Morphology of the surfaces and the cross-section of the grafted films were investigated by Scanning Electronic Microscopy(SEM)

which showed that the PET film surfaces were uniformly covered with a layer of azo moieties and its thickness was about 0.4 μm．The photo-induced orientation of the azo chromophores in the grafted films was examined．It was found that the azobenzene groups through rapid trans-cis isomerization oriented perpendicularly to the polarization direction of the light gradually resulting in anisotropic films

when the grafted films were irradiated with a 488 nm linear polarized light A max orientation order parameter about 0.06 was observed after 2 min irradiation．