| 摘要 |
An incombustible sound-damping shaped body of foamed structure consisting of a polymer material which is surface-coated at least on one face and containing optionally reinforcing elements, is made of a water-containing polymer obtained by polymerization of a reversed emulsion of styrene or its methyl homologues, and/or an acrylic acid ester and/or a methacrylic acid ester and, if desired, other compounds copolymerizable with these which are insoluble or only sparingly soluble in water, the water content of said polymer being at least 50%, calculated on the polymer. The shaped body may be coated with metal foils, metal-plastic bonded foils, bonded foils made of metal and paper, metal plates, plastic foils or coatings of suitable impermeability to water. The other copolymerizable compounds may be vinylidene chloride, vinyl esters, vinyl chloride, chloroprene and esters of fumaric and maleic acid. Cross-linking comonomers having two or three polymerizable double bonds as well as unsaturated polyesters may also be employed. In the preferred embodiment the polymerizable materials to be emulsified comprise mixtures of (a) 10 to 90% by weight, calculated on the total amount of polymerizable material, of styrene or its methyl homologues and (b) the balance consisting of a substantially unbranched unsaturated polyester having a molecular weight of 1000 to 9000, an acid number below 120 and containing maleic and/or fumaric acid in an amount of at least 50 mole per cent calculated on the total amount of polycondensed polycarboxylic acid. Conventional emulsifiers are used. Polymerization initiators mentioned are the persulphates and peroxides, preferably used in the presence of reducing agents such as pyrosulphites, bisulphites and thiosulphates or their alkali metal salts, or dimethylaniline or triethanolamine. Flame - impeding additives may be added to the water phase and/or to the monomer phase of the emulsion, e.g. borates, antimony trioxide and phosphoric acids or phosphates.ALSO:An incombustible sound-damping shaped body of foamed structure consisting of a polymer material which is surface-coated at least on one face and containing optionally reinforcing elements, is made of a water-containing polymer obtained by polymerization of a reversed emulsion of styrene or its methyl homologues, and/or an acrylic acid ester and for a methacrylic acid ester and, if desired, other compounds copolymerizable with these which are insoluble or only sparingly soluble in water, the water content of said polymer being at least 50%, calculated on the polymer. The shaped body may be coated with plastic coatings of suitable impermeability to water. In the preferred embodiment the polymerizable materials to be emulsified comprise mixtures of (a) 10 to 90% by weight, calculated on the total weight of polymerizable material, of styrene or its methyl homologues and (b) the balance consisting of a substantially unbranched unsaturated polyester having a molecular weight of 1, 000 to 9, 000, and acid number below 120 and containing maleic and/or fumaric acid in an amount of at least 50 mole % calculated on the total amount of polycondensed polycarboxylic acid. The shaped body may first be formed and then coated by polymerizing thereon. In Examples (a) a cube of polymerized casting material formed by the reversed emulsion polymerization of a polyester-styrene resin is coated by immersing the cube in a cold-hardening unsaturated polyester resin, and (b) a similar reversed emulsion is poured on to a steel sheet, polymerized and the uncovered surface is then coated with a polyester resin. Pipes may be coated with the reversed emulsion and then covered with a lining. |
