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Louisville, KY, United States

Druffel T.,Optical Dynamics Nanotechnology
Nanotechnology 2010: Advanced Materials, CNTs, Particles, Films and Composites - Technical Proceedings of the 2010 NSTI Nanotechnology Conference and Expo, NSTI-Nanotech 2010 | Year: 2010

Inorganic-organic nanocomposites offer a multitude of options to engineer abrasion resistance, improve UV weathering, enhance thermal conductivity, and control refractive index. Enhancements of this kind are typically only achieved if the nanoparticles are randomly dispersed as discrete entities within the polymer matrix. This constraint requires tight control of nanoparticle synthesis and chemical modification of the nanoparticle surface for appropriate polymerization within the matrix. Metal oxide nanocomposite coatings are distinguished by their high visible transparence and preservation of polymer flexibility. In this paper we discuss the deposition of nanocomposite coatings using techniques that are suitable for large and small areas. We also explore specific material properties and the behavior of these coatings under large strains.

Druffel T.,Optical Dynamics Nanotechnology | Lattis M.,Optical Dynamics Nanotechnology | Spencer M.,Optical Dynamics Nanotechnology | Buazza O.,Optical Dynamics Nanotechnology
Nanotechnology | Year: 2010

For nearly a century, dielectric materials have been used to produce thin film filters capable of precisely modifying electromagnetic wave interactions at material boundaries. Minimizing visible reflections from optical elements is the most mature use of these techniques, but modern applications often require advanced filters that operate in the ultraviolet or infrared regions. Vapour deposition is the dominant coating technology used to produce these filters, but sol-gel processes have also gained a footing. These methods have been used to create organic/inorganic hybrids that can theoretically withstand larger strains than a purely inorganic metal oxide, but demonstrations of thin film filters with strain properties similar to pure polymers have been sorely lacking. A homogeneous composite featuring inorganic nanoparticles in a polymer matrix is capable of very high strains without failure. We demonstrate such a system here with a 38-layer nanocomposite filter that is subjected to 20% strain with simultaneous evaluation of optical performance. The filter's reflectance peak shifts toward the shorter wavelengths as film thickness decreases in response to the strain, but the peak intensity of the reflected light does not substantially change. These results suggest that the nanocomposite layers are behaving as homogeneous materials with consistent optical parameters throughout the test. © 2010 IOP Publishing Ltd.

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