Abstract:
This invention provides gypsum wallboards with a unique microstructure where the walls between voids are enhanced in thickness and strength to substantially improve the strength and handling properties of the wallboards. A method of making lightweight gypsum wallboards is also provided.
Abstract:
The invention generally provides gypsum-containing slurries including stucco, naphthalenesulfonate dispersant, and pregelatinized starch. The naphthalenesulfonate dispersant is present in an amount of about 0.1% -3.0% by weight based on the weight of dry stucco. The pregelatinized starch present in an amount of at least about 0.5% by weight up to about 10% by weight of pregelatinized starch by weight based on the weight of dry stucco in the formulation. Other slurry additives can include trimetaphosphate salts, accelerators, binders, paper fiber, glass fiber, and other known ingredients. The invention also comprises the gypsum-containing products made with such slurries, for example, gypsum wallboard, and a method of making gypsum wallboard.
Abstract:
A gypsum composition, board, and method of producing a gypsum board with increased fire endurance are described. The set gypsum-containing composition can be used to prepare a gypsum board having fire endurance, based on the inclusion of silica gel.
Abstract:
A system and method for predicting wallboard fire performance in a standard test includes procuring a sample of the wallboard for testing, and mounting the sample into a fixture so that one side of the sample is exposed to a heat source. A cavity is created between the sample and the fixture such that the sample is disposed between the heat source and the cavity. A temperature measurement is taken at a predetermined location within the cavity over time, and the temperature is monitored and recorded as a series of temperature readings using a computer-readable medium. The series is analyzed to determine an index time at which the temperature reaches a predetermined temperature threshold. The index time is correlated to a standard-test fire performance using the computer-readable medium and, based on the correlation, a fire performance of the wallboard in a standard test procedure is predicted.
Abstract:
The invention generally provides gypsum-containing slurries including stucco, naphthalenesulfonate dispersant, and pregelatinized starch. The naphthalenesulfonate dispersant is present in an amount of about 0.1%-3.0% by weight based on the weight of dry stucco. The pregelatinized starch is present in an amount of at least about 0.5% by weight up to about 10% by weight of pregelatinized starch by weight based on the weight of dry stucco in the formulation. Other slurry additives can include trimetaphosphate salts, accelerators, binders, paper fiber, glass fiber, and other known ingredients. The invention also comprises the gypsum-containing products made with such slurries, for example, gypsum wallboard, and a method of making gypsum wallboard.
Abstract:
A reduced weight, reduced density gypsum panel that includes high expansion vermiculite with fire resistance capabilities that are at least comparable to (if not better than) commercial fire rated gypsum panels with a much greater gypsum content, weight and density.
Abstract:
Disclosed are product (e.g., panels), slurry, and methods relating to a pregelatinized starch having a mid-range viscosity (i.e., from about 20 centipoise to about 700 centipoise).
Abstract:
An about ⅝ inch to ¾ inch thick low weight, low density gypsum panel with fire resistance capabilities sufficient to provide a Thermal Insulation Index of at least 17.0 minutes which when subjected to U419 test procedures will not fail for at least 30 minutes and, in selected embodiments, also has outstanding water resistance properties.
Abstract:
Disclosed is a method and system for blending a foam modifier with foaming agent on-line, e.g., as may be particularly useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C6-C16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.
Abstract:
A reduced weight, reduced density gypsum panel that includes high expansion vermiculite with fire resistance capabilities that are at least comparable to (if not better than) commercial fire rated gypsum panels with a much greater gypsum content, weight and density.