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Composite panel containing polyurethane binder and method for production thereof Invention relates to a composite material and a method for production thereof. The composite material has a surface layer and an inner layer. The composite material contains a solid reinforcing material and a matrix. The matrix contains resin binder and solid polyurethane particles. The resin binder is a solid binder or a liquid binder. At least 50 wt % of the composite material is wood. The surface layer of the composite material contains solid polyurethane particles. To obtain composite material, resin binder and polyurethane particles are deposited on the solid reinforcing material to obtain a composite precursor and then treated to obtain composite material. The composite material is a directed-wood particle board, where the inner layer does not contain solid polyurethane particles. The invention enables to use polyurethane wastes and reduce use of the hazardous chemical methylene diphenyl diisocyanate when producing the binder. |
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Aerogel-based composite materials Composite material contains at least one polymer and one aerogel. The aerogel is covered by a layer of polymer, wax or inorganic material in order to considerably prevent the polymer from penetrating aerogel pores. The composite material is obtained by applying a coating on the aerogel. The coated aerogel is merged with an uncured polymer. The polymer is cured. |
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Method of preparing open-cell foamed material Invention relates to foamed material constituted by cross-linked amino-formaldehyde polymer product suitable for filtration of tobacco smoke. Foamed material according to invention contains cavities and intermediate spaces located outside of cavities, said spaces being confined by walls consisted of cross-linked amino-formaldehyde polymer product optionally supplemented by additives. Average space dimension lies within 30 to 350 μm. Considerable portion of spaces have two or more perforations with average diameter within a range of 5 to 300 μm in their walls while considerable portion of perforations of neighbor spaces are arranged relative to each other in such a way as to form continuous nonlinear path. Foamed material is characterized by porosity at least 45 vol % and specific surface area 0.1 to 15 m2/g. Method of preparing of such foamed material comprises following stages: mixing air and foaming agent solution under pressure in mixing zone of injector filled with multiple inert mixing members; passing, under pressure, non-hardened foam from mixing zone and prepolymer solution into reaction zone of injector to form curable foam; and discharging foam and drying it in air. Use of such foamed mixture as cigarette filter allows content of toxic compounds such as resins and polycyclic aromatic compounds to be lowered. |
Another patent 2542554.