The present invention relates to an admixture composition for the production of lightweight concretes containing polystyrene beads, which comprises a mixture of organic and inorganic substances which consists of the reaction products of polyurethane resin, tetraethyl orthosilicate, a glycol compound, an aromatic vinyl compound containing an unsaturated double bond, preferably styrene, and an inorganic silicate compound and preferably comprises the following components: glycol copolymer type compounds, in an amount of 15-10 w/w %, glycol polymer-silica type compounds, in an amount of 45-50 w/w %, polyurethane-based resin, in an amount of 13-22 w/w % polystyrene in an amount of 2-3% w/w %, and foam glass beads in an amount of 25-15 w/w %, and a) for the production of a liquid product, based on the total mass of the above composition, organic solvents in an amount of 15-20 w/w %, and water in an amount of 10-5 w/w %; or b) for the production of a solid preparation, based on the total mass of the above composition, polyvinyl acetate or polyvinyl alcohol in an amount of 10-5 w/w %; aluminium hydroxide in an amount of 2-5 w/w %, and calcined limestone powder in an amount of 8-10 w/w %. The invention also relates to the production and use of the above admixture composition.

The present invention relates to an admixture composition for the production of lightweight concretes containing polystyrene beads, which comprises a mixture of organic and inorganic substances which consists of the reaction products of polyurethane resin, tetraethyl orthosilicate, a glycol compound, an aromatic vinyl compound containing an unsaturated double bond, preferably styrene, and an inorganic silicate compound and preferably comprises the following components: glycol copolymer type compounds, in an amount of 15-10 w/w %, glycol polymer-silica type compounds, in an amount of 45-50 w/w %, polyurethane-based resin, in an amount of 13-22 w/w % polystyrene in an amount of 2-3% w/w %, and foam glass beads in an amount of 25-15 w/w %, and a) for the production of a liquid product, based on the total mass of the above composition, organic solvents in an amount of 15-20 w/w %, and water in an amount of 10-5 w/w %; or b) for the production of a solid preparation, based on the total mass of the above composition, polyvinyl acetate or polyvinyl alcohol in an amount of 10-5 w/w %; aluminium hydroxide in an amount of 2-5 w/w %, and calcined limestone powder in an amount of 8-10 w/w %. The invention also relates to the production and use of the above admixture composition.

A plasterboard comprising a gypsum matrix having wood particles embedded therein in an amount of at least 2 wt % relative to the gypsum, the gypsum matrix further comprising glass fibres in an amount of at least 1 wt % relative to the gypsum.

A plasterboard comprising a gypsum matrix having wood particles embedded therein in an amount of at least 2 wt % relative to the gypsum, the gypsum matrix further comprising glass fibres in an amount of at least 1 wt % relative to the gypsum.

Aqueous polymer dispersions are produced by radically initiated emulsion polymerization of ethylenically unsaturated monomers in the presence of protective colloids and/or emulsifiers in a continuously operated tubular reactor, characterized in that the direction of flow of the reactor contents is reversed along the longitudinal axis of the reactor over the course of polymerization.

In accordance with one or more embodiments of the present disclosure, a drilling fluid may include a base fluid, one or more formaldehyde-based resins, and one or more water-soluble acid catalysts. The base fluid may include an aqueous or non-aqueous solution. The one or more water-soluble acid catalysts may be present in an amount sufficient to reduce the pH of the drilling fluid to less than or equal to 6. The present disclosure also describes sealed subterranean petroleum formations that include such drilling fluids and methods for sealing subterranean wellbores by utilizing such drilling fluids.

In accordance with one or more embodiments of the present disclosure, a drilling fluid may include a base fluid, one or more formaldehyde-based resins, and one or more water-soluble acid catalysts. The base fluid may include an aqueous or non-aqueous solution. The one or more water-soluble acid catalysts may be present in an amount sufficient to reduce the pH of the drilling fluid to less than or equal to 6. The present disclosure also describes sealed subterranean petroleum formations that include such drilling fluids and methods for sealing subterranean wellbores by utilizing such drilling fluids.

A cement composition can include: water; cement, wherein less than 75 w/w % of the total amount of the cement is Portland cement; and a fluid loss additive, wherein the fluid loss additive comprises a polymer network having at least one branching point formed with a monomer and a cross-linking agent that comprises at least three active functional groups. The cement can also be a non-Portland cement. The monomer can be a vinyl ester-based monomer that is polymerized with the cross-linking agent to form the polymer network. The cement composition can be used in an oil and gas operation.

A cement composition can include: water; cement, wherein less than 75 w/w % of the total amount of the cement is Portland cement; and a fluid loss additive, wherein the fluid loss additive comprises a polymer network having at least one branching point formed with a monomer and a cross-linking agent that comprises at least three active functional groups. The cement can also be a non-Portland cement. The monomer can be a vinyl ester-based monomer that is polymerized with the cross-linking agent to form the polymer network. The cement composition can be used in an oil and gas operation.

A plasterboard comprising a gypsum matrix having wood particles embedded therein in an amount of at least 2 wt % relative to the gypsum, the gypsum matrix further comprising glass fibres in an amount of at least 1 wt % relative to the gypsum.