United States Gypsum Company

Knauf Gips Kg

Rutgers, the State University of New Jersey

United States Mineral Products Company

Usg Interiors, Inc.

Qinghua Li

Mark K Hemphill

Vahit Atakan

Richard E Riman

Yuan Zhu

Xiaogang Chen

Surojit Gupta

Jong-Kae Fwu

Ashish Dubey

Naveen Punati

Charles W Cochran

Naser Aldabaibeh

Seunghee Han

Alexei Vladimirovich Davydov

Yujian Zhang

Weixin David Song

Robert P Kreh

Wendy C Wong

Rafael Bury

Suman Sinha Ray

Yanfei Peng

Runhai Lu

Ling Tang

Trevor S Rische

Mark Antosh

Thomas E Nye

Cekdar Vakifahmetoglu

Xiaoyan Chen

Aaron D Johnson

Nicholas D′anna

Robert Paul Kreh

Yi Hsuan

Huaning Niu

Honggang Li

Hujun Yin

Xintian E Lin

Apostolos Papathanassiou

Tang Ling

This disclosure provides products useful as construction materials and containing set gypsum and ammonium-exchanged vermiculite, including a gypsum panel having a gypsum core comprising set gypsum and ammonium-exchanged vermiculite and characterized by decreased heat shrinkage and increased resistance to fire damage in comparison to the gypsum panel that comprises vermiculite that has not been ammonium-exchanged. The disclosure further relates to methods for producing the gypsum panel and constructing building assemblies with the gypsum panels, including walls and ceilings.

Gypsum panel containing ammonium-exchanged vermiculite and methods

A fire-resistant gypsum panel comprises: a gypsum core layer comprising set gypsum and a high temperature sag-resistant material including mineral wool in an amount between 0.2% and 3.0% by weight of gypsum.

High temperature sag resistant gypsum panel

A method of recovering desalinated activated alumina (AA) beads from a composition including salt laden (high salt absorbed) activated alumna (AA) beads and free anions and free cations, comprising the step of electrodialysis of the composition to reduce salt content of the activated alumina (AA) beads to produce a stream comprising the desalinated activated alumina (AA) beads.

Desalination of high chloride salt absorbed porous beads

Gypsum boards formed from synthetic gypsum and other gypsum sources having high chloride salt concentrations. Gypsum boards may include a board core including set gypsum between a front cover sheet and a back cover sheet. A total concentration of the chloride anion in the board core ranges from about 150 to 4000 parts by weight (pbw) chloride, typically about 300 to about 3000 pbw, more typically from about 400 to about 2000 pbw, further typically from about 1000 to about 2000 pbw, and further typically from about 600 to about 1000 pbw, per 1,000,000 pbw calcium sulfate dihydrate. A polymer layer contacts an inner surface of the back cover sheet. A densified gypsum layer contacts an inner surface of the front cover sheet. Methods of making the gypsum board, and a wall system for employing the gypsum boards, are also provided.

Gypsum board from gypsum having high level of chloride salt and a polymer layer and methods associated therewith

A gypsum wallboard having a core with a central core layer and one or more densified layers is disclosed. At least one densified layer contains salt absorbent particles of zeolite and/or hydrotalcite to improve adhesion of the gypsum core to a cover sheet. Also, methods of making the gypsum wallboard and a wall system for employing the gypsum wallboard are disclosed.

High salt gypsum wallboard containing salt absorbents and methods of making same

Disclosed are a composite gypsum board and a method of preparing composite gypsum board. The board contains set gypsum layers sandwiched between two cover sheets. The set gypsum layers are formed from at least stucco and water. The set gypsum layers include a board core and one or more skim coat layers. The set gypsum core makes up a substantial thickness (e.g., at least about 90%, at least about 92%, at least about 95%, or at least about 97%) of the total thickness of all the gypsum layers. A first skim coat layer is included on one side of the core, facing a first (face) cover sheet. A second skim coat layer is included on the other side of the core, facing a second (back) cover sheet. At least the second skim layer is formed from a slurry that contains starch. The stucco material generally includes a high salt impurity content, for example, when the stucco is calcined from certain sources of low-quality synthetic gypsum. For example, in some embodiments, the salts are chloride salts, e.g., sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl), and/or calcium chloride (CaCl).

Method of preparing gypsum wallboard from high salt gypsum, and related product

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.

Calcium aluminate cement and calcium sulfoaluminate cement catalysts in gypsum panels and use thereof

Disclosed are a composite gypsum board and a method of preparing composite gypsum board. The board contains at least one set gypsum layer sandwiched between two cover sheets. The set gypsum layer is formed from at least stucco and water. The stucco material generally includes a high salt impurity content, for example, when the stucco is calcined from certain sources of low-quality synthetic gypsum. For example, in some embodiments, the salts are chloride salts, e.g., sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl), and/or calcium chloride (CaCl)). At least one of the cover sheets is composed of high absorption paper, which enhances the bond between the set gypsum layer and the cover sheet.

Gypsum board containing high absorption paper and related methods

Disclosed are a composite gypsum board and a method of preparing composite gypsum board. The board contains a set gypsum core sandwiched between two cover sheets. The core is formed from a slurry containing stucco, water, and optional ingredients such as foaming agent, accelerator, retarder, polyphosphate, starch, and dispersant, and core intumescent material. The board also contains at least one skim coat and/or hard edges. A face skim coat layer can be included on one side of the core, facing a face cover sheet. A back skim coat layer can be included on the other side of the core, facing a back cover sheet. Hard edges are known in the art and can be formed, e.g., continuously from a stucco slurry for forming the face and/or back skim coats. Preferably, the back skim coat layer and/or the hard edges are formed from a slurry containing stucco, water, skim coat or edge intumescent material (which have the same desired characteristics), and other optional additives as desired. The skim coat or edge intumescent material can be composed of the same material as the core intumescent material, if desired, but the skim coat and/or edge intumescent material is present in a higher relative concentration in its respective slurry than the amount of core intumescent material in the core slurry. Examples of suitable intumescent materials include expandable vermiculite (e.g., No. 4 or No. 5 according to the US naming system, or combinations thereof), expandable graphite, perlite, or any combination thereof.

Fire resistant gypsum board and related methods

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.

Methods of removing chloride from gypsum having high level of chloride salt

The disclosure provides a coating composition for improving the sag resistance of a fibrous panel, the composition including 10 to 100 wt. % inorganic binder, based on the total weight of the dry coating, wherein the inorganic binder includes a borate salt and at least one of an alkali metal silicate or an alkaline earth metal silicate, and the inorganic binder is water soluble. Further provided are fibrous panels having a backing side and an opposing facing side including the coating of the disclosure, and methods of preparing same.

Borate and silicate coating for improved acoustical panel performance and methods of making same

Disclosed are an organic binder-based coating; a composite gypsum board containing face and back cover sheets, an outside surface of the back cover sheet bearing the coating; and a method of preparing composite board where the back cover sheet contains the coating on its outer surface. The coating is formed from a composition comprising an alkaline silicate, a solid filler, and optionally, a borate. An enhancing layer can also be applied to the back cover sheet.

Gypsum wallboard with enhanced fire resistance, and related coatings and methods

Gypsum boards formed from synthetic gypsum and other gypsum sources having high chloride salt concentrations. The gypsum boards may include a set gypsum board core layer between a front and back paper cover sheets. The back paper cover sheet has a plurality of perforations extending therethrough. Methods of making the gypsum boards, and a wall system for employing the gypsum boards, are also provided. The concentration of the chloride anion in aqueous gypsum slurry used to make the set gypsum board core layer and to perform the methods of the invention may range from about 500 ppm to about 3000 ppm, typically from about 500 ppm to about 2000 ppm per 1,000,000 parts by weight calcium sulfate hemihydrate, more typically from about 500 ppm to about 1500 ppm per 1,000,000 parts by weight calcium sulfate hemihydrate.

Gypsum board from gypsum having high level of chloride salt and a perforated sheet and methods associated therewith

Gypsum boards formed from synthetic gypsum and other gypsum sources having high chloride salt concentrations. Gypsum boards may include a board core including set gypsum. A total concentration of the chloride anion in the board core ranges from about 500 ppm to about 3000 ppm, typically about 1000 ppm to about 3000 ppm, based on weight of the calcium sulfate hemihydrate. An inner surface of a front paper cover sheet contacts a first face of the board core. An inner surface of a back paper cover sheet contacts a second face of the board core. A starch layer coats the inner surface of at least one of the front and back cover sheet. Methods of making the gypsum board, and a wall system for employing the gypsum boards, are also provided.

Gypsum board from gypsum having high level of chloride salt and a starch layer and methods associated therewith

Aqueous cementitious slurries including predominantly Type I Portland cement containing an aluminate additive. The aluminate additive is an aluminate salt other than calcium aluminate or calcium sulfoaluminate, preferably sodium aluminate. Cementitious reactive powders of the slurry include the Type I Portland cement and 0.1-10 wt. % of the aluminate additive as an accelerator. The slurries may have a set time of about 10 minutes or less. Due to the short set time, the cementitious reactive powders may facilitate cement board fabrication by continuous manufacturing processes. Methods for making cement boards may include disposing the aqueous cementitious slurry including the cementitious reactive powders in a continuous layer, preferably upon a porous support, and setting the aqueous cementitious slurry with a set time of about 10 minutes or less.

Growing community of inventors

Rolling Meadows, IL, United States of America

Qinghua Li