Photoinduced formation of gold nanoparticles into vinyl alcohol based polymers

Nanocomposites based on vinyl alcohol-containing polymers and nanostructured gold have been efficiently prepared by a UV photo-reduction process. The very fast process provided dispersed gold nanoparticles with average diameters ranging from 3 to 20 nm depending on the host polymer matrix and the irradiation time. Uniaxial drawing of the irradiated Au/polymer nanocomposites favours the anisotropic distribution of packed assemblies of gold particles, providing oriented films with polarization-dependent tunable optical properties. These pronounced dichroic properties suggest that the nanocomposite films could find potential applications as colour polarizing filters, radiation responsive polymeric objects and smart flexible films in packaging applications.