Abstract: Water-resistant gypsum products may be produced using a novel catalyst that includes calcium aluminate cement and/or calcium sulfoaluminate cement. For example, a water-resistant gypsum panel may have a core comprising: interwoven matrices of calcium sulfate dihydrate crystals and a silicone resin, wherein the interwoven matrices have dispersed throughout them a siloxane polymerization catalyst comprising (a) 55 wt % to 100 wt % calcium aluminate cement and/or calcium aluminate cement and (b) 0 wt % to 45 wt % and magnesium oxide, wherein the weight ratio of the siloxane polymerization catalyst to the calcium sulfate dihydrate is 0.01-5:100. The water-resistant gypsum panel may have an absence of one or more of: Portland cement, limestone, aragonite, calcite, dolomite, and slaked lime.

Abstract: Beads of materials such as activated alumina, zeolite and silica gel, are used as chloride salt absorbers. The beads are mixed with high-salt gypsum. After mixing for a short time, the mixtures are dried, and the beads and the powder are separated by using a sieve or other physical separation device resulting in a low-salt gypsum which can be used as a gypsum source to make gypsum wallboard.

Abstract: A cementitious panel system reinforced on its opposed surfaces by a fabric of basalt fiber woven or non-woven mesh. Preferably the mesh is a woven basalt scrim with thicker yarn and larger mesh openings to provide a cementitious panel with improved handling properties while retaining tensile strength and long term durability. The fabric is constructed as a mesh of high modulus strands of bundled basalt fibers. The fabric also has suitable physical characteristics for embedment within the cement matrix of the panels or panels closely adjacent the opposed faces thereof. The fabric provides a panel system with long-lasting, high strength tensile reinforcement and improved handling properties regardless of their spatial orientation during handling. Included as part of the invention are methods for making the reinforced cementitious panel.

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: Beads of materials such as activated alumina, zeolite and silica gel, are used as chloride salt absorbers. The beads are mixed with high-salt gypsum. After mixing for a short time, the mixtures are dried, and the beads and the powder are separated by using a sieve or other physical separation device resulting in a low-salt gypsum which can be used as a gypsum source to make gypsum wallboard.

Abstract: Water-resistant gypsum products may be produced using a novel catalyst that includes calcium aluminate cement and/or calcium sulfoaluminate cement. For example, a water-resistant gypsum panel may have a core comprising: interwoven matrices of calcium sulfate dihydrate crystals and a silicone resin, wherein the interwoven matrices have dispersed throughout them a siloxane polymerization catalyst comprising (a) 55 wt % to 100 wt % calcium aluminate cement and/or calcium aluminate cement and (b) 0 wt % to 45 wt % and magnesium oxide, wherein the weight ratio of the siloxane polymerization catalyst to the calcium sulfate dihydrate is 0.01-5:100. The water-resistant gypsum panel may have an absence of one or more of: Portland cement, limestone, aragonite, calcite, dolomite, and slaked lime.

Abstract: Continuous method including mixing water and cementitous powder to form slurry; mixing the slurry and reinforcement fibers in a single pass horizontal continuous mixer to form fiber-slurry mixture, the mixer including an elongated mixing chamber having a reinforcement fiber inlet port, and upstream of the fiber inlet port is an inlet port to introduce water and cementitous powder together as one stream or at least two inlet ports to introduce water and dry cementitous powder separately as separate streams into the chamber, a rotating horizontal shaft/s within the chamber, part of the chamber for mixing the fibers and slurry and moving the fiber-slurry mixture to a mixture outlet; discharging the fiber-slurry mixture from the mixer outlet; forming and setting the fiber-slurry mixture on a moving surface; cutting the set mixture into fiber reinforced concrete panels and removing the panels from the moving surface.

Abstract: A method in which a stream of dry cementitious powder passes through a first conduit and aqueous medium stream passes through a second conduit to feed a slurry mixer to make cementitious slurry. The cementitious slurry passes through a third conduit and a reinforcement fiber stream passes through a fourth conduit to feed a fiber-slurry mixer which mixes the slurry and discrete fibers to make a stream of fiber-slurry mixture. An apparatus for performing the method is also disclosed.

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: Self-consolidating geopolymer compositions utilizing fly ash and inorganic mineral including alkaline earth metal oxide as cementitious reactive components and include cement set retarder. The alkaline earth metal oxide is preferably calcium oxide (also known as lime or quicklime) and/or magnesium oxide. The inorganic minerals including alkaline earth metal oxide have an alkaline earth metal oxide content preferably greater than 50 wt. %, more preferably greater than 60 wt. %, even more preferably greater than 70 wt. %, and most preferably greater than 80 wt. %, for example greater than 90 wt. %. The cementitious reactive powder may optionally also include one or more aluminous cements and one or more source of calcium sulfates. The cementitious reactive powders are activated with an alkali metal chemical activator selected from alkali metal salt and/or alkali metal base. Methods for making the compositions are also disclosed.

Abstract: A slurry feed apparatus for depositing a slurry upon a moving forming web having a direction of travel, including: a headbox mounted transverse to the direction of travel of the moving web, having a back wall, sidewalls, a concave transverse front wall, an open top, and an open bottom for directing slurry onto the forming web; a moveable dam releasably attached to the back wall, a seal attached to a bottom wall of the dam; and a headbox support system extending from opposed the sidewalls. Also disclosed is a continuous process for depositing a uniform layer of a cementitious slurry containing reinforcing fibers from the headbox onto a traveling web.

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. The waterproof gypsum panels of the invention have many uses, such as, tilebacker board in wet or dry areas of buildings, exterior weather barrier panel for use as exterior sheathing, and roof cover board having water durability and low surface absorption. The flexible and hydrophobic cementitious finish can include fly ash, film-forming polymer, 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: Self-consolidating geopolymer compositions utilizing fly ash and inorganic mineral including alkaline earth metal oxide as cementitious reactive components and include cement set retarder. The alkaline earth metal oxide is preferably calcium oxide (also known as lime or quicklime) and/or magnesium oxide. The inorganic minerals including alkaline earth metal oxide have an alkaline earth metal oxide content preferably greater than 50 wt. %, more preferably greater than 60 wt. %, even more preferably greater than 70 wt. %, and most preferably greater than 80 wt. %, for example greater than 90 wt. %. The cementitious reactive powder may optionally also include one or more aluminous cements and one or more source of calcium sulfates. The cementitious reactive powders are activated with an alkali metal chemical activator selected from alkali metal salt and/or alkali metal base. Methods for making the compositions are also disclosed.

Abstract: A method in which a stream of dry cementitious powder from a dry powder feeder passes through a dry cementitious powder inlet conduit to feed a first feed section of a fiber-slurry mixer. An aqueous medium stream passes through at least one aqueous medium stream conduit to feed a first mixing section the fiber-slurry mixer. A stream of reinforcing fibers passes from a fiber feeder through a reinforcing fibers stream conduit to feed a second mixing section of the fiber-slurry mixer. The stream of dry cementitious powder, aqueous medium stream, and stream of reinforcing fibers combine in the fiber-slurry mixer to make a stream of fiber-cement mixture which discharges through a discharge conduit at a downstream end of the mixer.

Abstract: A method for making geopolymer cementitious binder compositions for cementitious products such as concrete, precast construction elements and panels, mortar and repair materials, and the like is disclosed. The geopolymer cementitious compositions of some embodiments are made by mixing a synergistic mixture of thermally activated aluminosilicate mineral, calcium aluminate cement, a calcium sulfate and a chemical activator with water.

Abstract: Cementitious binder compositions for cementitious products including a hydraulic cement-based reactive powder blend, an inorganic flow control agent, and a metal-based dimensional movement stabilizing agent including at least one member of the group of lithium salt and lithium base, and methods for making the cementitious binder compositions.

Abstract: Geopolymer compositions utilizing fly ash and an inorganic mineral including alkaline earth metal oxide as cementitious reactive components. The inorganic mineral includes alkaline earth metal oxide preferably calcium oxide (also known as lime or quicklime) or magnesium oxide, or combinations thereof. The cementitious reactive powder may also optionally include one or more aluminous cements and one or more source of calcium sulfates. The cementitious reactive powders are activated with an alkali metal chemical activator selected from at least one member of the group consisting of an alkali metal salt and an alkali metal base. The inorganic minerals including alkaline earth metal oxide preferred in this invention have an alkaline earth metal oxide content preferably greater than 50 wt %, more preferably greater than 60 wt %, even more preferably greater than 70 wt %, and most preferably greater than 80 wt %, for example greater than 90 wt %. Methods for making the compositions are also disclosed.

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 method for making geopolymer cementitious binder compositions for cementitious products such as concrete, precast construction elements and panels, mortar, patching materials for road repairs and other repair materials, and the like is disclosed. The geopolymer cementitious compositions of some embodiments are made by mixing a synergistic mixture of thermally activated aluminosilicate mineral, calcium sulfoaluminate cement, a calcium sulfate and a chemical activator with water.