National Gypsum Properties, LLC

Gopalakrishnan Sethuraman

Amba Ayambem

W Roy Burke

Richard E Smith

Ronald S Finkelstein

Richard J Romanek

Joseph J Bailey

Eli Stav

Ma-Ikay Miatudila

Karen Fey

Larry W Kingston

Elisha Stav

Lambert J Metz

Craig Robertson

Charles Dennis Price

John L Phillips

Claudette Brown

Robert C Mitchell

Roy W Burke

Compositions for gypsum board are disclosed, comprising a mixture of a gypsum slurry and a pre-generated foam and a coalescing agent. The coalescing agent comprises one or more coalescing agents that are added to the composition singly, separately or in combination to change the size and distribution of the air bubbles in the foamed gypsum slurry. The resulting gypsum cores have increased nail pull resistance and an improved facer/gypsum core bond.

Gypsum wallboard and method of making same

The disclosure relates to a method for effectively and efficiently adding sodium trimetaphosphate to a gypsum slurry. In one exemplary embodiment, the sodium trimetaphosphate is added at the same time as foam is added to the gypsum slurry through the foam waterline. In another exemplary embodiment, the sodium trimetaphosphate is added at the same time as additional water is added to the gypsum slurry through the gauging waterline. The sodium trimetaphosphate can be added to either or both waterlines in its dry form or in a diluted solution.

Method of adding STMP to a gypsum slurry

Gypsum wallboard compositions are disclosed which contain functionalized styrene butadiene latex polymers. Methods for the use of the compositions in the manufacture of wallboard panels and sheets is presented.

Gypsum layered panels containing styrene butadiene latex additive

Methods of preparing gypsum wallboards containing styrene butadiene latex additive

Compositions useful for the preparation of lightweight, high strength wallboards, and methods of making same are disclosed. The composition includes a slurry of calcium sulfate hemihydrate (stucco), water, starch, and a foam. The foam acts to provide large bubbles within the core slurry, thereby lightening the weight of the wallboard. The composition and method provide wallboards having lighter weights compared to standard wallboard, increased core strength, and increased paper-to-core bonding.

Lightweight wallboard compositions containing natural polymers

The invention provides a method of providing void spaces in gypsum wallboard and in a gypsum core composition such that the weight of the gypsum product is reduced without deleteriously affecting its mechanical properties. More specifically, the invention provides a method of providing void spaces in a gypsum wallboard comprising the step of adding air bubbles having different relative stabilities to a gypsum slurry, wherein the less stable air bubbles are sufficiently unstable such that they coalesce on contact with each other in the slurry to form larger air bubbles, and the weight ratio of the less stable air bubbles to the more stable air bubbles initially added to the slurry is such that there are a sufficient number of more stable air bubbles to prevent a majority of the less stable air bubbles from becoming large enough to rupture before the slurry sets sufficiently to prevent the slurry from filling void spaces left by ruptured bubbles. The method further includes the steps of mixing the air bubble-containing gypsum slurry to distribute the air bubbles throughout the slurry to form a core composition of gypsum wallboard, depositing the core composition on a cover sheet, and, applying a second cover sheet over the core composition to form a gypsum wallboard.

Method of providing void space in gypsum wallboard and in a gypsum core composition

A method of producing calcium sulfate &agr;-hemihydrate is disclosed, including the steps of exposing a mixture including a calcium sulfate form selected from the group consisting of calcium sulfate dihydrate, calcium sulfate &bgr;-hemihydrate, water-soluble calcium sulfate anhydrite, and mixtures thereof, water, and a crystallization catalyst, to microwave radiation to produce calcium sulfate &agr;-hemihydrate; and separating at least a portion of the calcium sulfate &agr;-hemihydrate to provide a solid comprising calcium sulfate &agr;-hemihydrate and a filtrate and/or remainder that can be recycled to provide at least one of a calcium sulfate form, water, a crystallization catalyst, a crystal habit modifier, and a surfactant for use in production of additional &agr;-hemihydrate.

Method of producing calcium sulfate alpha-hemihydrate

A joint compound includes water, calcium carbonate, and a water-soluble polymeric set retarder formed from a monomer having two or more carboxyl groups. The joint compound is useful in various applications and in a hybrid joint compound made with a calcium sulfate hemihydrate setting-type joint compound.

Joint compound and method of using same

Gypsum composition with ionic styrene butadiene latex additive

Joint compound and method of making same

A static foam generating apparatus including a pipe having an inner diameter, an axis, an input end, and an output end is disclosed. A plurality of perforated discs are disposed in the pipe, the discs positioned parallel to each other and perpendicular to the pipe axis. A plurality of spacer rings are disposed within the pipe, a spacer ring separating each perforated disc from each adjacent perforated disc. Additionally, a method for generating foam including the steps of providing a static foam generating apparatus including a pipe having an inner diameter, an axis, an input end, and an output end, supplying feed water to the pipe, supplying surfactant to the pipe, and supplying air to the pipe is disclosed.

Growing community of inventors

East Amherst, NY, United States of America

Gopalakrishnan Sethuraman