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.
A novel polyelectrolyte PNANT functionalized with electron donor-acceptor type azobenzene chromophores has been synthesized through post-polymerization azo coupling reaction and characterized by 1H-NMR,FTIR and UV-Vis spectroscopy.The degree of functionalization (DF) of PNANT was 20% measured by elemental analysis.The degree of polymerization and its distribution were determined by GPC to be X n=251 with a polydispersion index 1.53.A glass transition temperature of 119℃ was observed from DSC thermogram. H-aggregation of azo chromophores of PNANT in spin-coated film and self-assembled film were detected from UV-Vis spectra,and the degree of H-aggregation of PNANT in the self-assembled film was found to be higher than that in the spin-coated film.Dichroism was optically induced in the spin-coated film and self-assembled film upon the irradiation of a polarized Ar + laser beam at 488 nm.The orientational order parameter obtained was 0.15 for spin-coated film and 0.07 for the self-assembled film.The resulting dichroism detected by UV-Vis spectra exhibited long-term stability.
