A new kind of amorphous molecular materials containing azobenzene chromophors has been synthesized.The precursor molecule was prepared by esterification between 1,3,5-benzenetricarbonyl chloride and N-ethyl-N-hydroxyethyl-aniline.The precursor molecule was then reacted with the diazonium salts of 5-aminoisophthalic acid to introduce donor-acceptor azobenzene chromophores at the peripheral groups.The azobenzene amorphous molecular material was characterized by the spectroscopic methods and thermal analysis.The azo compound synthesized can form stable amorphous glass.The amorphous molecular material was used to fabricate surface relief gratings(SRG) by exposing spin-coated thin films of the azo compound to an interference pattern of Ar^+ laser beams at modest intensity(120 mW/cm^2).The surface modulation was about 390 nm and the first order of diffraction efficiency was up to 23%.
Multilayer films of a polyacrylate-based azo polyelectrolyte were fabricated by a spin self-assembly method.By spin-coating solutions of the azo polyelectrolyte in DMF/H2O mixed solvent and polydiallyldimethylammonium chloride（PDAC） in water,high quality multilayer films were obtained.Dichroism was optically induced in the self-assembled films under the irradiation of a polarized Ar+ laser beam at 488 nm.The dichroism was easily detected from UV-Vis spectra and exhibited long term stability.The orientational order parameter obtained was about 0.06 for the film.With interfering illumination of Ar+ laser beams,significant surface relief gratings formed on the self-assembled multiplayer films were observed.
