Abstract: The present invention provides a gypsum molded product having excellent waterproof properties without impaired strength by adding alkaline metal alkylsiliconates or phenylsiliconates together with calcium hydroxide or calcium oxide to gypsum; poly(.alpha.,.beta.-unsaturated carboxylic acid) may be used in combination with the above, if desired. According to the present invention, the preparation of a gypsum molded product, particularly a gypsum from desulfurization of exhaust gas, is contemplated.

Abstract: The present invention provides a gypsum molded product having excellent waterproof properties without impaired strength by adding alkaline metal alkylsiliconates or phenylsiliconates together with calcium hydroxide or calcium oxide to gypsum; poly(.alpha.,.beta.-unsaturated carboxylic acid) may be used in combination with the above, if desired. According to the present invention, the preparation of a gypsum molded product, particularly a gypsum from desulfurization of exhaust gas, is contemplated.

Abstract: Present invention provides foamed gypsum moulded articles excellent in sound absorbing property and production thereof. The foamed gypsum moulded article has many foam-cells, and the foam-cells are interconnected through fine passages. The fine passages are formed using as a decomposition catalyst of hydrogen peroxide for expansion a cobalt compound produced by pretreating a water soluble cobalt salt with hydrogen peroxide in the presence of alkali. The foamed gypsum moulded article is preferably applicable to an interial wall, ceiling panel, and the like.

Abstract: The flexible polyurethane foams having high flame resistance and smoke resistance can be produced by reacting a polyhydroxyl compound and a polyisocyanate with a urea derivative selected from the group consisting of(a) a compound represented by the general formula ##STR1## wherein at least one of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represents hydroxylalkyl, alkoxyalkyl, alkyl and aryl groups and the remainder represents hydrogen atom, and(b) a urea-formaldehyde condensation product in the presence of a catalyst, a surfactant and a blowing agent.These polyurethane foams can easily provide the favorable foam sheets by compression-molding these foams under heating.

Abstract: The flexible polyurethane foams having high flame resistance and smoke resistance can be produced by reacting a polyhydroxyl compound and a polyisocyanate with a urea derivative selected from the group consisting of(a) a compound represented by the general formula ##STR1## wherein at least one of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represents hydroxylalkyl, alkoxyalkyl, alkyl and aryl groups and the remainder represents hydrogen atom, and(b) a urea-formaldehyde condensation product in the presence of a catalyst, a surfactant and a blowing agent.These polyurethane foams can easily provide the favorable foam sheets by compression-molding these foams under heating.

Abstract: An excellent flame- and smoke-retardant non-shrinkable polyurethane foam is prepared by reacting a polyhydroxyl compound consisting of(A) a polyol having at least two hydroxyl groups and having a molecular weight of from 1,000 to 10,000, and(B) an aliphatic amino alcohol, the amount of which is 2.1 to 8.0 equivalents per hydroxyl group of the polyol (A) with an organic polyisocyanate in the presence of water and/or other blowing agents, catalysts and surfactants.The polyurethane foam thus obtained has high resilience together with an improved S.A.G. factor.

Abstract: A flame-resistant and smoke-retardant polyurethane foam is produced by reacting a polyisocyanate with a polyhydroxyl compound in the presence of an alkaline earth metal salt of a carboxylic acid and a foaming agent.

Abstract: A thermoplastic and organic solvent-soluble poly(amide-imide) elastomer having a number average molecular weight ranging from 10,000 to 100,000, prepared by reacting (1) an acid anhydride functional polymer, represented by the following formula ##STR1## or a mixture of said acid anhydride functional polymer (1) and a tetracarboxylic acid dianhydride, with (2) a dicarboxylic acid dihydrazide in the presence of an aprotic dipolar solvent at a temperature ranging from -10.degree. C to 30.degree. C.

Abstract: A catalyst for reduction of nitrogen oxides in the presence of ammonia, which can be advantageously prepared by treating titanium slag with sulfuric acid at an elevated temperature, optionally followed by treatment with an alkali, and decomposing the resulting product while heating at a temperature of about 400.degree. to 700.degree. C and has a high catalytic activity with a long catalytic life and a high resistance to acid substances.

Abstract: The reduction of nitrogen oxides is effected by passing stack offgases containing nitrogen oxides over a heavy metal sulfide catalyst in an atmosphere where ammonia is present.

Abstract: A flexible elastomer resin having an improved impact resistance and strength is produced by reacting an acid anhydride group functional polymer, which is prepared by reacting a hydroxyl group functional polymer having a number average molecular weight of 400 to 10,000 and containing at least two hydroxyl groups at the end or the side chain with a tricarboxylic acid anhydride monohalide, with at least one nitrogen compound having polyfunctional active hydrogens and at least one epoxy resin having at least one epoxy group.

Abstract: A dihalocyclopropane functional multi-component copolymer is produced by reacting olefin bond units contained in the side chain or in the cyclic group in the main chain of a multi-component copolymer with dihalocarbene generated from halogenated hydrocarbon in the presence of a cation surfactant catalyst by using an alkali aqueous solution. The dihalocyclopropane functional multi-component copolymer has an excellent compatibility as a polymer to be blended with the general purpose rubber and as a halogenated rubber series industrial material.