Preparation and Optical Properties of New Metal/Macromolecule Architectures

Abstract

Abstract Polymer nanocomposite films with unusual and anisotropic optical properties were obtained by the controlled in‐situ generation of noble metal nanoparticles (NPs). Poly(vinyl alcohol) (PVA) and poly(ethylene‐ co ‐vinylalcohol) (EVAl) nanocomposites containing gold and silver NPs were efficiently produced by a photo‐reduction or thermal process both operating directly in the solid state and resulted efficiently stabilized by the presence of polymer hydroxyl groups, which prevent particles agglomeration. Uniaxial drawing of the NPs/polymer composites promoted anisotropic packing of the embedded particles along the stretching direction of the film, resulting in a shift of the surface plasmon resonance well above 40 nm and thus producing a well‐defined polarization‐dependent colour change. Such nanostructured materials when are obtained in the form of thin films can be applied to several fields, from sensor to photonics (i.e., macromolecular strain sensor, linear absorbing polarizer).