Evolution of Silver Nanoparticles Synthesized In Situ in a Glass-Like Epoxy Matrix

The evolution of silver nanoparticles (NPs) synthesized in situ in an epoxy matrix is investigated. The change in the stability of epoxy nanocomposites as a result of secondary processes of the transformation of NPs in a glass-like epoxy matrix when stored under natural light and in darkness is shown by means of absorption spectroscopy. The first order of the reaction and the dependence of the rate constant on the concentration of the precursor are found. Possible mechanisms for the conversion of silver NPs (e.g., digestive ripening and the formation of anisotropic structures) are discussed. It is concluded that the glass-like state of the polymer matrix is not a sufficient condition for the stabilization of NPs or the stability of the properties of the nanocomposite. This must be considered in the study and practical application of polymer nanocomposites (NCs) based on metal nanoparticles.