Disclosed is a CO.sub.2 solidified fiber cement board and its preparation method. The matrix composition of the fiber cement board prepared in this disclosure is calcium carbonate, which has high compactness, and the crystal form of calcium carbonate is adjusted by adding shell powder to improve the toughness of the matrix, so that the fiber cement board has excellent mechanics and durability performance. In addition, the preparation process does not require high temperature maintenance, and has the characteristics of normal temperature preparation, which creates conditions for the introduction of organic synthetic fibers, so that the organic synthetic fibers can further improve the brittleness of cement fiberboard. While reducing energy consumption, the preparation process can also effectively solve the problem that excessive pressure is easily generated in the fiberboard under high temperature conditions in the existing high-temperature and high-pressure curing process.

A free-flowing powder composition includes at least one substrate having pores and an external surface between said pores, said surface functionalized with at least one accelerator for a hydraulic setting composition, said accelerator being liquid, hygroscopic, or deliquescent, and wherein after 15 minutes of immersion of free-flowing powder composition in water at 20° C. at least 80% in weight of said accelerator is solubilized, said free-flowing powder composition being immersed in an amount of water sufficient so that the saturation concentration of said accelerator cannot be reached. There is also a method for preparing said free-flowing powder composition. The use of said free-flowing powder composition as an additive for mortar or concrete composition provides an accelerating effect, an anti-ageing effect and an anti-dusting effect. A dry mortar or concrete composition includes a hydraulic binder, said free-flowing powder composition and a granulate, wet mortar or concrete composition and hardened body obtained therefrom.

A free-flowing powder composition includes at least one substrate having pores and an external surface between said pores, said surface functionalized with at least one accelerator for a hydraulic setting composition, said accelerator being liquid, hygroscopic, or deliquescent, and wherein after 15 minutes of immersion of free-flowing powder composition in water at 20° C. at least 80% in weight of said accelerator is solubilized, said free-flowing powder composition being immersed in an amount of water sufficient so that the saturation concentration of said accelerator cannot be reached. There is also a method for preparing said free-flowing powder composition. The use of said free-flowing powder composition as an additive for mortar or concrete composition provides an accelerating effect, an anti-ageing effect and an anti-dusting effect. A dry mortar or concrete composition includes a hydraulic binder, said free-flowing powder composition and a granulate, wet mortar or concrete composition and hardened body obtained therefrom.

A powder adhesive composition having cement, a dispersible polymer powder; and at least 10% volume of the powder adhesive is an expanded perlite. The cement is at a ratio of between 600-1000% of the mass of the expanded perlite. The powder adhesive composition is an adhesive, and the adhesion strength of the adhesive, is over 0.4 MPa, after 28 days, and after water immersion for at least 20 days.

A powder adhesive composition having cement, a dispersible polymer powder; and at least 10% volume of the powder adhesive is an expanded perlite. The cement is at a ratio of between 600-1000% of the mass of the expanded perlite. The powder adhesive composition is an adhesive, and the adhesion strength of the adhesive, is over 0.4 MPa, after 28 days, and after water immersion for at least 20 days.

This application relates to making magnesium oxychloride boards. A magnesium oxychloride slurry is mixed by directing magnesium chloride, magnesium oxide, at least one phosphate, at least one inorganic salt, and water into a mixer and mixing these ingredients together to form a slurry. At least one filler is then mixed with the slurry. The slurry is directed to a mold. The mold is formed with the slurry to form a magnesium oxychloride board. The magnesium oxychloride board is then cured.

This application relates to making magnesium oxychloride boards. A magnesium oxychloride slurry is mixed by directing magnesium chloride, magnesium oxide, at least one phosphate, at least one inorganic salt, and water into a mixer and mixing these ingredients together to form a slurry. At least one filler is then mixed with the slurry. The slurry is directed to a mold. The mold is formed with the slurry to form a magnesium oxychloride board. The magnesium oxychloride board is then cured.

Disclosed herein is a fiber reinforced cementitious composition comprising a cementitious binder and at least one synthetic inorganic reinforcing fiber type, wherein the synthetic inorganic reinforcing fiber type comprises at least one of a man-made mineral fiber type such as basalt fibers, an aluminosilicate wool fiber type or an alkaline earth silicate wool fiber type.

Disclosed herein is a fiber reinforced cementitious composition comprising a cementitious binder and at least one synthetic inorganic reinforcing fiber type, wherein the synthetic inorganic reinforcing fiber type comprises at least one of a man-made mineral fiber type such as basalt fibers, an aluminosilicate wool fiber type or an alkaline earth silicate wool fiber type.

Process for producing a thermally insulating mixture comprising hydrophobic silica, in which a) a pulverulent carrier material selected from the group consisting of precipitated silicas, SiO.sub.2 aerogels, pearlites and mixtures thereof is coated with a liquid silicon compound, where the liquid silicon compound has at least one alkyl group and a boiling point of less than 200° C., and b) the pulverulent carrier material that has thus been coated with the liquid silicon compound is mixed with a composition comprising a pulverulent hydrophilic fumed silica and the mixture is subjected to thermal treatment at more than 40° C. and c) any unreacted silicon compound is subsequently removed from the thermally treated mixture, thus giving the thermally insulating mixture comprising hydrophobic silica.