Optical limiters based on silver nanoparticles embedded in amorphous polystyrene

A simple technique to prepare plastic color-filters based on the surface plasmon resonance (SPR) of silver nanoparticles has been developed. In particular, silver/polystyrene nanocomposites have been prepared by dissolving silver acetylacetonate in amorphous polystyrene and heating the obtained solid solution at a convenient temperature (ca. 200 degrees C). When the metal precursor decomposes, the produced silver atoms diffuse into the polymeric matrix and clusterize, leading to the formation of a contact-free dispersion of hyperfine silver phase. The obtained films have been characterized by UV-VIS spectroscopy and the optical extinction spectra have been fitted by the Mie's theory, introducing the limitation of the mean free path due to the collisions of conduction electrons with the boundary of the nanoparticles.