A process for increasing the hydrophobicity of a porous product by treating the product, or a composition providing for the product, with a water repellent material, characterized in that the porous product or a composition providing the product, is treated with an aqueous suspension of microcapsules where the microcapsules comprise a water repellent organosilicon core material selected from an organosilane, a partially condensed organosilane and a branched siloxane resin, and a shell of a silicon-based network polymer comprising silica units.

A process for increasing the hydrophobicity of a porous product by treating the product, or a composition providing for the product, with a water repellent material, characterized in that the porous product or a composition providing the product, is treated with an aqueous suspension of microcapsules where the microcapsules comprise a water repellent organosilicon core material selected from an organosilane, a partially condensed organosilane and a branched siloxane resin, and a shell of a silicon-based network polymer comprising silica units.

A process for increasing the hydrophobicity of a porous product by treating the product, or a composition providing for the product, with a water repellent material, characterized in that the porous product or a composition providing the product, is treated with an aqueous suspension of microcapsules where the microcapsules comprise a water repellent organosilicon core material selected from an organosilane, a partially condensed organosilane and a branched siloxane resin, and a shell of a silicon-based network polymer comprising silica units.

The present disclosure relates more particularly to calcium sulfate-based slurries useful, for example, in making gypsum boards for building construction, as well as methods for using them, e.g., to make gypsum boards, in one aspect, the present disclosure provides a calcium sulfate slurry composition comprising calcium sulfate present substantially in the form of one or more hydrates, the calcium sulfate being present in an amount in the range of 70-99.8 wt % on a dry basis, calculated as stucco; and a cationic starch present in an amount of 0.10-10 wt % of the amount of calcium sulfate as stucco on a dry basis, the cationic starch being substituted with amine and/or ammonium groups and having a % N value in the range of 0.10 wt. % to 2 wt %, and an RVA viscosity value of at least 100 cP at 65° C. and 16 wt %; and water, in an amount sufficient to form a slurry. The disclosure also provides gypsum-based materials useful as building materials, e.g., for use as building boards in construction of walls and ceilings of buildings.

The present disclosure relates more particularly to calcium sulfate-based slurries useful, for example, in making gypsum boards for building construction, as well as methods for using them, e.g., to make gypsum boards, in one aspect, the present disclosure provides a calcium sulfate slurry composition comprising calcium sulfate present substantially in the form of one or more hydrates, the calcium sulfate being present in an amount in the range of 70-99.8 wt % on a dry basis, calculated as stucco; and a cationic starch present in an amount of 0.10-10 wt % of the amount of calcium sulfate as stucco on a dry basis, the cationic starch being substituted with amine and/or ammonium groups and having a % N value in the range of 0.10 wt. % to 2 wt %, and an RVA viscosity value of at least 100 cP at 65° C. and 16 wt %; and water, in an amount sufficient to form a slurry. The disclosure also provides gypsum-based materials useful as building materials, e.g., for use as building boards in construction of walls and ceilings of buildings.

Water-based paint is used as a sacrificial agent to reduce the detrimental effect of carbon-containing fly ash on the entrainment of air in concrete. The invention provides a composition for reducing the effect of carbon contained in fly ash on air entrainment in cementitious mixtures comprising water, cement, fly ash and entrained air. The composition comprises water-based paint and one or more of pulverized or un-pulverized pozzolan, pulverized or un-pulverized cementitious solids, a superplasticizer, a defoamer, an air-entraining admixture, a water-reducing admixture, a retarding admixture, an accelerating admixture, a hydration control admixture and a rheology modifying admixture. The invention also provides a method of reducing the effect of carbon on air entrainment in carbon-containing fly ash, comprising mixing the fly ash with water-based paint.

Water-based paint is used as a sacrificial agent to reduce the detrimental effect of carbon-containing fly ash on the entrainment of air in concrete. The invention provides a composition for reducing the effect of carbon contained in fly ash on air entrainment in cementitious mixtures comprising water, cement, fly ash and entrained air. The composition comprises water-based paint and one or more of pulverized or un-pulverized pozzolan, pulverized or un-pulverized cementitious solids, a superplasticizer, a defoamer, an air-entraining admixture, a water-reducing admixture, a retarding admixture, an accelerating admixture, a hydration control admixture and a rheology modifying admixture. The invention also provides a method of reducing the effect of carbon on air entrainment in carbon-containing fly ash, comprising mixing the fly ash with water-based paint.

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.

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.