U.S. Patent 9,163,125 (October 20, 2015), "Method of Preparing a Transparent Polymer Material Comprising a Thermoplastic Polycarbonate and Surface-Modified Mineral Nanoparticles," Anne Christmann, Jean-Francois Hochepied, Jose-Marie Lopez-Cuesta, Laure Meynie, Alexandra Roos, Nathalie Cornet, Karine Cavalier, Didier Sy, and Marc Lacroix (Armines and Essilor International (Compagnie Generale D'Optique), Paris, France, and Solvay SA, Brussels, Belgium).
Polycarbonate has excellent transparency, shock resistance, high refractive index, and relatively low density. But it tends to be too flexible and sensitive to scratching and abrasion. Mineral nanoparticles can improve these properties, but particle aggregation remains a problem.
Christmann et al. avoided this problem using mineral nanoparticles coated with a monomer and a polymer for optimizing interactions with the polymer and preventing aggregation. Binding of the monomer and polymer is promoted using chlorosilane or organosilane coupling agents. Alkaline-earth metal carbonates, alkaline-earth metal sulfates, metallic oxides, oxides of metalloids, and/or siloxanes particles of 10- to 70-nm size can be added without aggregation by extrusion at up to 15 wt% loading.
This material can be thermoformed, extruded, calendered, drawn, injection molded, injection-compression molded, or blow molded without loss of mechanical and optical properties.
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|Title Annotation:||INDUSTRY PATENTS; Compagnie Generale D'Optique patent received|
|Comment:||Polycarbonate nanocomposites.(INDUSTRY PATENTS)(Compagnie Generale D'Optique patent received)|
|Article Type:||Brief article|
|Date:||Feb 1, 2016|
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