Nanocomposites with tailored optical properties

Nanostructures have many useful physical and chemical properties that can be advantageously used to provide polymers, resins, and elastomers of important functional characteristics. Polymer embedding of nanostructures originates a quite broad class of novel materials named nanocomposites. Nanocomposite materials based on optical plastics (polystyrene (PS), poly(methyl methacrylate) (PMMA), polycarbonate (PC), thermoplastic polyurethane (TPU), epoxy, etc.) combine the physical properties of the embedded nanostructures to optical transparency in visible spectral region and therefore they represent a typical class of multifunctional materials. In addition, many other properties can be simultaneously combined together in such nanocomposite materials: 0D nanostructures, like noble metal nanoparticles or clusters (i.e., nanoparticles with a diameter ranging between 1 and 2 nm), can be used to dye the polymers by the surface plasmon resonance (SPR) of coin metals or to make them fluorescent (molecular Au clusters), magnetic (Fe2O3 nanoparticles), antiseptic (e.g., Ag nanoparticles), radioopaque (Pb nanocrystals), antistatic, with ultrahigh or infralow refractive index (Os and Ag clusters, respectively), etc. The metal nanoparticle aggregation process allows to fabricate stimuli-responsive materials like thermochromic materials that are able to switch the color at a special temperature. In this case, nanoparticles need to be coated by a self-assembled thiol monolayer which collapse at a particular temperature, thus increasing the interparticle distance in the aggregate and modifying the SPR position.