Abstract: Fabric reinforcement for reinforcing alkaline cementitious matrix including warp yarns and weft yarns. To increase cohesive tensile strength of intersection points of the fabric the fabric has sufficient resinous coating over a substantial portion of the warp and weft yarns, before the fabric reinforcement is embedded within, or adhesively or mechanically bonded to the cementitious matrix, wherein the coating includes organic or inorganic adhesives/polymers, or the fabric has uncoated fabric modified by adhering fabric strands together where machine direction and cross-machine strands intersect, for example with cyanoacrylate or epoxy. Bond strength of the intersecting yarns of the fabric and the corresponding mechanical bond strength of the fabric to the cementitious matrix may also be enhanced by increasing roughness and/or surface area of the yarns and resulting fabric. Methods for making fabric, cementitious boards employing the fabric, and methods for making the cementitious board are also provided.

Abstract: A production line and process including a moving carrier web for transporting the panel, and a device for controlling thickness of a formed, but not yet set, fiber reinforced cementitious panel slurry on the web. The thickness control device may include an angled rigid plate for contacting a downstream end of the angled plate with the slurry on the moving carrier web and a mounting stand for mounting the angled rigid. The thickness control device may include a flat horizontal plate at a fixed height over the moving carrier for contacting the entire lower surface of the horizontal plate with a facer on the slurry on the moving carrier web. Or, the thickness control device may include the angled plate and include the horizontal plate that contacts the facer.

Abstract: A production line and process including a moving carrier web for transporting the panel, and a device for controlling thickness of a formed, but not yet set, fiber reinforced cementitious panel slurry on the web. The thickness control device may include an angled rigid plate for contacting a downstream end of the angled plate with the slurry on the moving carrier web and a mounting stand for mounting the angled rigid. The thickness control device may include a flat horizontal plate at a fixed height over the moving carrier for contacting the entire lower surface of the horizontal plate with a facer on the slurry on the moving carrier web. Or, the thickness control device may include the angled plate and include the horizontal plate that contacts the facer.

Abstract: Embodiments of a system and a method for continuously manufacturing a joint compound can be used to produce ready mix joint compound. The system includes means for continuously mixing wet and dry joint compound ingredients together and means for homogenizing multiple volumetric units of mixed joint compound to reduce variation in at least one joint compound material property (e.g., viscosity) across multiple successively produced volumetric units of mixed joint compound (relating to standard commercial packaging sizes for joint compound, such as five-gallon pails, for example) relative to the material property of the respective multiple volumetric units before passing through the means for homogenizing.

Abstract: Disclosed are hydrophobic finish compositions and cementitious articles made with the hydrophobic finish compositions. In some embodiments, the article is a waterproof gypsum panel surface reinforced with inorganic mineral fibers that face a flexible and hydrophobic cementitious finish possessing beneficial waterproofing properties. These waterproof gypsum panels have many uses, such as, tile backer board in wet or dry areas of buildings, exterior weather barrier panel for use as exterior sheathing, interior wall and ceiling, and roof cover board having water durability and low surface absorption. The flexible and hydrophobic cementitious finish can include fly ash, film-forming polymer, preferably silane compound (e.g., alkyl alkoxysilane), an extended flow time retention agent including either one or more carboxylic acids, salts of carboxylic acids, or mixtures thereof, and other optional additives.

Abstract: Disclosed is an improved facer mat for use as a cover sheet for gypsum board. Also disclosed are gypsum boards containing such mat facers on one or both major surfaces of the board (face and back sides when installed), a method of manufacturing such board, and a method of making the mat. The mat can comprise glass, thermoplastic, and/or thermoset fiber. In preferred embodiments, binder is included with the fiber. The mat has outer and inner surfaces. The mat comprises a first region adjacent to the outer surface defined along a horizontal plane of the mat, the first region having a first substantial thickness, and a second region adjacent to the inner surface defined along a horizontal plane of the mat, the second region having a second substantial thickness. The first region has (a) more hydrophilicity than the second region, (b) more wettability than the second region, and/or (c) less density than the second region.

Abstract: Disclosed is an improved facer mat for use as a cover sheet for gypsum board. Also disclosed are gypsum boards containing such mat facers on one or both major surfaces of the board (face and back sides when installed), a method of manufacturing such board, and a method of making the mat. The mat can comprise glass, thermoplastic, and/or thermoset fiber. In preferred embodiments, binder is included with the fiber. The mat has outer and inner surfaces. The mat comprises a first region adjacent to the outer surface defined along a horizontal plane of the mat, the first region having a first substantial thickness, and a second region adjacent to the inner surface defined along a horizontal plane of the mat, the second region having a second substantial thickness. The first region has (a) more hydrophilicity than the second region, (b) more wettability than the second region, and/or (c) less density than the second region.

Abstract: Disclosed is an improved facer mat for use as a cover sheet for gypsum board. Also disclosed are gypsum boards containing such mat facers on one or both major surfaces of the board (face and back sides when installed), a method of manufacturing such board, and a method of making the mat. The mat can comprise glass, thermoplastic, and/or thermoset fiber. In preferred embodiments, binder is included with the fiber. The mat has outer and inner surfaces. The mat comprises a first region adjacent to the outer surface defined along a horizontal plane of the mat, the first region having a first substantial thickness, and a second region adjacent to the inner surface defined along a horizontal plane of the mat, the second region having a second substantial thickness. The first region has (a) more hydrophilicity than the second region, (b) more wettability than the second region, and/or (c) less density than the second region.

Abstract: Disclosed are hydrophobic finish compositions and cementitious articles made with the hydrophobic finish compositions. In some embodiments, the article is a waterproof gypsum panel surface reinforced with inorganic mineral fibers that face a flexible and hydrophobic cementitious finish possessing beneficial waterproofing properties. These waterproof gypsum panels have many uses, such as, tile backer board in wet or dry areas of buildings, exterior weather barrier panel for use as exterior sheathing, interior wall and ceiling, and roof cover board having water durability and low surface absorption. The flexible and hydrophobic cementitious finish can include fly ash, film-forming polymer, preferably silane compound (e.g., alkyl alkoxysilane), an extended flow time retention agent including either one or more carboxylic acids, salts of carboxylic acids, or mixtures thereof, and other optional additives.

Abstract: A water-resistant gypsum fiber product comprising siloxane and coated with a coating comprising alkali metal organosiliconate is provided. A method of making a gypsum fiber product in which siloxane is cross-linked at the surface of the product is also provided. A fuel-efficient method for making the product and reducing the amount of siloxane dust released is provided as well.

Abstract: Effective use of dispersants in wallboard containing foam results from a method where stucco is mixed with a first dispersant and a first quantity of water to form a gypsum slurry. A soap is blended with a second dispersant and a second quantity of water to make a foam. Subsequently, the foam is combined with the slurry. Choice of different first and second dispersants and their relative amounts allows control of the size distribution of the foam bubbles in the slurry and the resulting voids in the gypsum core. Melamine sulfonate condensate and polycarboxylate dispersants are preferred dispersants.

Abstract: A water-resistant gypsum fiber product comprising siloxane and coated with a coating comprising alkali metal organosiliconate is provided. A method of making a gypsum fiber product in which siloxane is cross-linked at the surface of the product is also provided. A fuel-efficient method for making the product and reducing the amount of siloxane dust released is provided as well.

Abstract: A gypsum slurry is provided that includes calcium sulfate hemihydrate; water; a dispersant component comprising at least one of the following a comb-branched polymer with polyether side chains, naphthalene sulfonate-formaldehyde condensate or melamine sulfonate-formaldehyde condensate; a foaming agent; and a polycondensation component with three polycondensation repeating units. Also provided is a method for making a gypsum slurry with a foaming agent in which the ratio between the dispersant component and the polycondensation component is adjusted to control for the size of foam bubbles in the gypsum slurry. Gypsum products made from the gypsum slurry are provided and methods for making the products are provided as well.

Abstract: A gypsum slurry is provided that includes calcium sulfate hemihydrate; water; a dispersant component comprising at least one of the following a comb-branched polymer with polyether side chains, naphthalene sulfonate-formaldehyde condensate or melamine sulfonate-formaldehyde condensate; a foaming agent; and a polycondensation component with three polycondensation repeating units. Also provided is a method for making a gypsum slurry with a foaming agent in which the ratio between the dispersant component and the polycondensation component is adjusted to control for the size of foam bubbles in the gypsum slurry. Gypsum products made from the gypsum slurry are provided and methods for making the products are provided as well.

Abstract: A panel is provided that includes stucco, water and a dispersant component having dispersing properties and comprising a comb-branched polymer with polyether side chains, naphthalene sulfonate-formaldehyde condensate or melamine sulfonate-formaldehyde condensate. A polycondensation component is also included in the slurry that includes three repeating units. A method of making the gypsum panel includes combining stucco, water and a first dosage of a first dispersant to form a slurry, the first. A second dosage of a second dispersant is added to the slurry. Properties of the gypsum slurry are tested and it is formed into a product. The product sets and properties of the product are identified. The first dosage or the second dosage is changed based on the properties of the slurry or product.

Abstract: Effective use of dispersants in wallboard containing foam results from a method where stucco is mixed with a first dispersant and a first quantity of water to form a gypsum slurry. A soap is blended with a second dispersant and a second quantity of water to make a foam. Subsequently, the foam is combined with the slurry. Choice of different first and second dispersants and their relative amounts allows control of the size distribution of the foam bubbles in the slurry and the resulting voids in the gypsum core. Melamine sulfonate condensate and polycarboxylate dispersants are preferred dispersants.

Abstract: One or more of these or other problems are improved using a method of making a strong gypsum panel which includes a method for forming a hardened shell structure at the interface of a foamed bubble and a gypsum slurry. A strengthening component is selected from the group consisting of set accelerators, water soluble polyphosphate salts, blends of water soluble polyphosphate salts with starch, boric acid, fibers, glycerin or combinations thereof. The strengthening component is combined with a foaming agent and with water to form an aqueous soap mixture. Foam is generated from the aqueous soap mixture, and added to a gypsum slurry. Allowing the strengthening component to contact the soap bubbles prior to addition of the foam to the gypsum slurry allows the strengthening component to preferentially contact the soap film rather than be dispersed through the entire slurry.

Abstract: A gypsum slurry is described that includes water, a hydraulic component comprising at least 50% calcined gypsum by weight based on the dry weight of the hydraulic component, foam, a defoamer and a polycarboxylate dispersant. In some embodiments of the invention, the defoamer is combined with the dispersant prior to being added to the gypsum slurry. The defoamer and dispersant can be added as a physical mixture, wherein the defoamer is attached onto the dispersant polymer, or a combination thereof. A gypsum building panel is made from the gypsum slurry.

Abstract: A gypsum slurry is described that includes water, a hydraulic component comprising at least 50% calcined gypsum by weight based on the dry weight of the hydraulic component, foam, a defoamer and a polycarboxylate dispersant. In some embodiments of the invention, the defoamer is combined with the dispersant prior to being added to the gypsum slurry. The defoamer and dispersant can be added as a physical mixture, wherein the defoamer is attached onto the dispersant polymer, or a combination thereof. In some embodiments, a gypsum building panel is made from the gypsum slurry.

Abstract: A gypsum slurry is described that includes water, a hydraulic component comprising at least 50% calcined gypsum by weight based on the dry weight of the hydraulic component, foam, a defoamer and a polycarboxylate dispersant. In some embodiments of the invention, the defoamer is combined with the dispersant prior to being added to the gypsum slurry. The defoamer and dispersant can be added as a physical mixture, wherein the defoamer is attached onto the dispersant polymer, or a combination thereof. A gypsum building panel is made from the gypsum slurry.