Preparation and Properties of Inverse Nanoparticle-Polymer Composites

This dissertation presents how the drawbacks of low–filled nanoparticle–polymer composites can be overcome by initially preparing a stable percolating inorganic nanoparticle framework, in which very high porosity is achieved, either from the gas phase by flame spray pyrolysis (FSP) or, alternatively, via wet chemical preparation using a sol–gel process. Subsequently, the percolating structures are filled with a monomer by capillary–driven infiltration, which is then photochemically polymerized. The obtained system is called inverse nanoparticle–polymer composite. Thin–film layers from the composite can be applied, for example, as adhesion–promoting, electrical or optoelectronic functional materials. The original particle network and pore structure is preserved during the preparation, and the electrical conductivity of semiconducting nanoparticles could be significantly increased by infiltration, as well as subsequent monomer polymerization. An analytical model of the reaction kinetics was developed for free radical photopolymerization under spatial confinement within the mesoscale pore structure and confirmed by diffuse reflectance FTIR spectroscopy (DRIFTS).