Abstract: Fire resistant gypsum panels are provided herein, with assemblies including the same, and methods for making the same. A gypsum panel includes a set gypsum core and a mat facing material. The set gypsum core includes a fire resistant additive. The fire resistant additive consists essentially of clay, or a non-intumescent fire resistant additive. The panel displays an acceptable fire rating without requiring the use of vermiculite or intumescent materials.

Abstract: Paper and/or mat-faced gypsum board is prepared by applying a relatively thin coating of aqueous gypsum slurry containing a polyvinyl alcohol binder to one or two facer sheets. The polyvinyl alcohol binder provides adequate adhesion between the set gypsum core and the adjacent facer sheet(s) without the need for starch or other conventional binders. In one embodiment, polyvinyl alcohol is concentrated in one or more regions of the core adjacent to the facer sheet(s). In another embodiment, polyvinyl alcohol is applied to an aqueous gypsum slurry used to form the bulk core, such that the polyvinyl alcohol is present throughout the core.

Abstract: A method for increasing the drying rate of set plaster by adding fatty alcohol sulfate to the slurry of calcium sulfate hemihydrate from which the plaster is made.

Abstract: Paper and/or mat-faced gypsum board is prepared by applying a relatively thin coating of aqueous gypsum slurry containing a polyvinyl alcohol binder to one or two facer sheets. The polyvinyl alcohol binder provides adequate adhesion between the set gypsum core and the adjacent facer sheet(s) without the need for starch or other conventional binders. In one embodiment, polyvinyl alcohol is concentrated in one or more regions of the core adjacent to the facer sheet(s). In another embodiment, polyvinyl alcohol is applied to an aqueous gypsum slurry used to form the bulk core, such that the polyvinyl alcohol is present throughout the core.

Abstract: A method for increasing the drying rate of set plaster by adding fatty alcohol sulfate to the slurry of calcium sulfate hemihydrate from which the plaster is made.

Abstract: A fire resistant article comprising at least about 65 wt. % gypsum dihydrate, reinforcing fibers disposed substantially homogeneously throughout said set gypsum dihydrate, inorganic binder, and optionally refractive filler. This composition provides superior resistance to damage when subjected to a stream of pressurized water as from a fire hose.

Abstract: Binder compositions are provided which are principally composed of a lime-containing flyash, and optionally hydratable gypsum, with a small amount of a property improving additive. The compositions are capable of setting when mixed with sufficient water to form a hardened material having a high degree of compressive strength after only about 1 hour following set. In selected embodiments, compositions are provided for floor underlayment, road patch and exterior statuary applications. Compressive strengths starting at about 600 psi can be achieved within 1 hour after set with adequate working time for construction applications.