The invention relates to a process for hydrophobization of concrete or mortar using an alkylketene dimer dispersion and to the concrete or mortar obtainable by the process of the invention. The process allows to achieve effective mass and surface hydrophobization of concrete.

The invention relates to a process for hydrophobization of concrete or mortar using an alkylketene dimer dispersion and to the concrete or mortar obtainable by the process of the invention. The process allows to achieve effective mass and surface hydrophobization of concrete.

The present invention relates to a method for producing a gypsum-containing foamed prefabricated building material and to a gypsum-containing foamed prefabricated building material.

The present invention relates to a method for producing a gypsum-containing foamed prefabricated building material and to a gypsum-containing foamed prefabricated building material.

The present invention provides compositions for use as stable additive concentrates, such as aqueous solutions or powders, in cement admixtures comprising i) one or more nonionic or substantially nonionic vinyl or acrylic brush polymers having pendant or side chain polyether groups and having a weight average molecular weight of from 140,000 to 50,000,000, ii) one or more aromatic cofactors containing one or more phenolic groups or, in combination, one or more aromatic groups with at least one sulfur acid group, preferably, a branched aromatic cofactor; and iii) one or more polycarboxylate ether copolymer water reducers containing carboxylic acid or salt groups and having polyether side chains and a weight average molecular weight of from 5,000 to 100,000.

The present invention provides compositions for use as stable additive concentrates, such as aqueous solutions or powders, in cement admixtures comprising i) one or more nonionic or substantially nonionic vinyl or acrylic brush polymers having pendant or side chain polyether groups and having a weight average molecular weight of from 140,000 to 50,000,000, ii) one or more aromatic cofactors containing one or more phenolic groups or, in combination, one or more aromatic groups with at least one sulfur acid group, preferably, a branched aromatic cofactor; and iii) one or more polycarboxylate ether copolymer water reducers containing carboxylic acid or salt groups and having polyether side chains and a weight average molecular weight of from 5,000 to 100,000.

A well cementing composition comprises water, an inorganic cement, a gas generating agent and a gas stabilizer. The gas generating agent may contain materials that release hydrogen gas, carbon dioxide gas or nitrogen gas or combinations thereof. The gas stabilizer comprises an aqueous mixture comprising polyglycols, oxyalkylates and methanol, or coco trimethyl ammonium chloride, or a mixture comprising ammonium fatty alcohol ether sulfate and ethylene glycol monobutyl ether, or combinations thereof. When used to cement a subterranean well, the compositions improve the compressive strength, increase the rate at which compressive strength develops, preserve cement homogeneity, or enhance cement expansion or a combination thereof.

A well cementing composition comprises water, an inorganic cement, a gas generating agent and a gas stabilizer. The gas generating agent may contain materials that release hydrogen gas, carbon dioxide gas or nitrogen gas or combinations thereof. The gas stabilizer comprises an aqueous mixture comprising polyglycols, oxyalkylates and methanol, or coco trimethyl ammonium chloride, or a mixture comprising ammonium fatty alcohol ether sulfate and ethylene glycol monobutyl ether, or combinations thereof. When used to cement a subterranean well, the compositions improve the compressive strength, increase the rate at which compressive strength develops, preserve cement homogeneity, or enhance cement expansion or a combination thereof.

This invention provides gypsum wallboards with a unique microstructure where the walls between voids are enhanced in thickness and strength to substantially improve the strength and handling properties of the wallboards. A method of making lightweight gypsum wallboards is also provided.

This invention provides gypsum wallboards with a unique microstructure where the walls between voids are enhanced in thickness and strength to substantially improve the strength and handling properties of the wallboards. A method of making lightweight gypsum wallboards is also provided.