The present invention is directed to a gypsum board and a method of making such gypsum board. For instance, the gypsum board comprises a gypsum core, a first facing material, and a second facing material wherein the first facing material and the second facing material sandwich the gypsum core. The gypsum core comprises a first gypsum core section and a second gypsum core section each comprising gypsum, wherein the first gypsum core section comprises a polyol compound and has a density higher than a density of the second gypsum core section.

The present invention is directed to a gypsum board and a method of making such gypsum board. For instance, the gypsum board comprises a gypsum core, a first facing material, and a second facing material wherein the first facing material and the second facing material sandwich the gypsum core. The gypsum core comprises a first gypsum core section and a second gypsum core section each comprising gypsum, wherein the first gypsum core section comprises a polyol compound and has a density higher than a density of the second gypsum core section.

A slurry for manufacturing gypsum board is disclosed. The slurry comprises calcined gypsum, water, a foaming agent, and a thickening agent. The thickening agent of the present disclosure acts to improve the cohesiveness of the slurry without adversely affecting the setting time of the slurry, the paper-to-core bond (wet and dry), or the head of the slurry by acting as a defoaming agent or coalescing agent. Examples of suitable thickening agents include cellulose ether and co-polymers containing varying degrees of polyacrylamide and acrylic acid. A gypsum board and method of forming the slurry and the gypsum board are also disclosed. The gypsum board comprises a gypsum layer formed from the slurry.

A slurry for manufacturing gypsum board is disclosed. The slurry comprises calcined gypsum, water, a foaming agent, and a thickening agent. The thickening agent of the present disclosure acts to improve the cohesiveness of the slurry without adversely affecting the setting time of the slurry, the paper-to-core bond (wet and dry), or the head of the slurry by acting as a defoaming agent or coalescing agent. Examples of suitable thickening agents include cellulose ether and co-polymers containing varying degrees of polyacrylamide and acrylic acid. A gypsum board and method of forming the slurry and the gypsum board are also disclosed. The gypsum board comprises a gypsum layer formed from the slurry.

Disclosed is a non-sintering method for preparing an artificial cobblestone from dredged soil, comprising the steps of: (1) preparing raw materials; (2) proportioning four types of materials; (3) preparing high-strength non-sintering ceramsite; (4) preparing a cobblestone core; (5) preparing a primary product of the cobblestone; (6) polishing; (7) curing; and (8) forming a finished product. In the method, the dredged soil is used as the raw material to prepare the artificial cobblestone with a core-shell structure, so that an application range of dredged soil recycling utilization can be widened, and a method for preparing artificial cobblestones is provided. By employing the non-sintering method for preparation, the energy consumption for production is low, and a decorative effect of the cobblestone can be achieved.

Disclosed is a non-sintering method for preparing an artificial cobblestone from dredged soil, comprising the steps of: (1) preparing raw materials; (2) proportioning four types of materials; (3) preparing high-strength non-sintering ceramsite; (4) preparing a cobblestone core; (5) preparing a primary product of the cobblestone; (6) polishing; (7) curing; and (8) forming a finished product. In the method, the dredged soil is used as the raw material to prepare the artificial cobblestone with a core-shell structure, so that an application range of dredged soil recycling utilization can be widened, and a method for preparing artificial cobblestones is provided. By employing the non-sintering method for preparation, the energy consumption for production is low, and a decorative effect of the cobblestone can be achieved.

The present invention relates to substantially water free hydraulic cement pastes which remain shelf stable over extended time periods, for example, 100 days at room temperature. The substantially water free cement pastes comprise a deep eutectic solvent mixture of a polar organic carrier component, such as a hydrogen donor like a polyol, in association with an anhydrous cation containing component, and a hydraulic cement, preferably, an aluminate cement, or sulpho-aluminate cement. A preferred deep eutectic solvent mixture comprises K.sub.2CO.sub.3 and glycerol in molar ratios of from 1:1 to 1:6. The cement pastes are activated simply by addition of water or aqueous polymers to form thin set compositions.

The present invention relates to substantially water free hydraulic cement pastes which remain shelf stable over extended time periods, for example, 100 days at room temperature. The substantially water free cement pastes comprise a deep eutectic solvent mixture of a polar organic carrier component, such as a hydrogen donor like a polyol, in association with an anhydrous cation containing component, and a hydraulic cement, preferably, an aluminate cement, or sulpho-aluminate cement. A preferred deep eutectic solvent mixture comprises K.sub.2CO.sub.3 and glycerol in molar ratios of from 1:1 to 1:6. The cement pastes are activated simply by addition of water or aqueous polymers to form thin set compositions.

An accelerator for accelerating the rate of hydration of calcined gypsum is disclosed. The accelerator comprises calcium sulfate dihydrate particles and a starch. The starch has a cold water solubility of at least about 25% (e.g., at least about 35%) and a viscosity of about 25 Brabender Units (BU) or less when the starch is in a 30% aqueous slurry at 92° C. Also disclosed are a method of preparing an accelerator, method of hydrating stucco to form set gypsum, slurry, and method of making gypsum board.

A combination of retarders and regulators for hydration reaction of cementitious binders including clinkers based on Ye'elimite. Set retarders are calcium complexing agents, consisting of sugar acids, sugars, sugar alcohols, hydroxycarboxylic acids, phosphates, phosphonates, borates and amines. Regulator general formula (I) is

##STR00001##

where M is H, NH.sub.4 or chosen from monovalent or divalent metal of groups Ia, IIa, IIIa, Ib, IIb, IVb, VIb, VIIb or VIIIb of periodic table of elements, where M is a divalent metal, a second equivalent of R—SO.sub.3 is present, and M is chosen from group consisting of H, NH.sub.4, Li, Na, K, MgX, CaX, or NiX with X═RSO.sub.3, and R is chosen from H, NH.sub.2, OH or from hydrocarbon chain with 1-18 C atoms which may be substituted by N and/or O and/or which may be linear or branched and/or which contain one or more unsaturated bonds and/or cycloaliphatic and/or aromatic moieties.