Abstract
| - Novel hybrid polymeric systems with noble metal nanoparticles located inside specific areasof the material were developed. A self-assembled multilayered polymer, poly(octadecylsiloxane) (PODS), provided a nanostructured matrix for incorporation of gold and platinumcompounds and for metal nanoparticle formation. The internal structure of PODS and thenanoparticle size distributions were examined using anomalous small-angle X-ray scattering.The ordering in PODS was largely preserved after interaction with metal compounds andreducing agents. The degree of incorporation of the compounds into PODS depended on thereaction conditions and on the compound type. For the metal-containing PODS isolated fromthe reaction medium before reduction, the major fraction of the nanoparticles had radiiaround 2 nm, and the size distributions depended neither on the compound loading nor onthe reducing agent. This points to a “cage”-controlled particle growth restricted by the cavitysize in the siloxy bilayer. This hypothesis is corroborated by the computed density profilesacross the PODS lamella. Incorporation of cetylpyridinium chloride in the hydrophobic layersof PODS promotes formation of nanoparticles also between the hydrophobic tails. Thislocation does not restrict the particle growth so that the nanoparticle sizes strongly dependon the reduction conditions.
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