摘要:
A gypsum-based composite structure is prepared from a slurry comprising a mixture of calcium sulfate hemihydrate, a cellulose ether additive other than CMC and an amount of water that is sufficient to form a slurry. The calcium sulfate hemihydrate is hydrated by the water forming a wallboard core reinforced by the cellulose ether additive. The concentration, viscosity grade and degree of substitution of the cellulose ether are selected to give the composite improved nail pull resistance and greater flexural strength.
摘要:
A reinforced wallboard core is prepared from a slurry comprising a mixture of null-calcium sulfate hemihydrate, a cellulose ether additive other than CMC and an amount of water that is sufficient to form a slurry and resulting in a wallboard density of less than 0.8 g/cc. The null-calcium sulfate hemihydrate is hydrated by the water forming a wallboard core reinforced by the cellulose ether additive. The cellulose ether, having a molecular weight of at least about 20,000 and a viscosity grade of at least about 100 cps, is selected to give the reinforced wallboard core improved nail pull resistance and greater flexural strength than unreinforced wallboard of the same density. The reinforced wallboard core may be used for reduced-paper wallboard and/or for lightweight wallboard, for example.
摘要:
A type of composite material where the matrix material and additive are held together by covalently or non-covalently bound ligands is described. A particularly useful composite material covered by the present invention is a carbon nanotube-reinforced composite material where the matrix consists of a polymer, covalently attached to a linker, where said linker is non-covalently attached to the carbon nanotube. Methods for the preparation of such composite materials are provided.
摘要:
Light-weight, fire-resistant “mineral foam” includes an inorganic cementitious matrix and at least one metal hydrate that is a “super hydrate” substance, in which water is present with the substance in an amount of at least about ten moieties of water of hydration per formula unit of the substance. As a cured solid, that “mineral foam,” or another mineral foam composition including an inorganic cementitious matrix, can be provided as a structural member in part of an assembly that has at least one open web, thermally insulating support member at least partially embedded in the cured solid. Also, the cured “mineral foam” may be a solid foam in a form of a panel, panel block or tile, which may have a tongue provision and/or a groove provision.
摘要:
A cover material for a bulk material pile and method for applying the cover material are disclosed. The cover composition comprises liquid, cement and/or fly ash, fiber, water dispersible polymer and acid.
摘要:
Disclosed are polymeric additives for concrete formed of a polyoxymethylene (POM) copolymer, POM copolymers can be utilized to form fibrous additives for concrete, i.e., microfibers and/or macrofibers. The POM copolymers can include one or more chemical groups, e.g., end groups and/or pendant groups that can increase the polarity of the POM and increase the hydrophilicity of the formed fibers, which can improve miscibility of the fibers in wet concrete. Chemical groups of the POM copolymers can bond with components of the concrete or can hydrolyze to form groups that can bond with components of the concrete, e.g., form covalent or noncovalent (e.g., electrostatic or ionic) bonds with one or more components of the concrete binder.
摘要:
A cover material for a bulk material pile and method for applying the cover material are disclosed. The cover composition comprises liquid, cement and/or fly ash, fiber, water dispersible polymer and acid.
摘要:
A lightweight ready-mix concrete composition that contains 8-20 volume percent cement, 11-50 volume percent sand, 10-31 volume percent prepuff particles, 9-40 volume percent coarse aggregate, and 10-22 volume percent water, where the sum of components used does not exceed 100 volume percent;. The prepuff particles have an average particle diameter of from 0.2 mm to 8 mm, a bulk density of from 0.02 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3. The slump value of the composition measured according to ASTM C 143 is from 2 to 8 inches. After the lightweight ready-mix concrete composition is set for 28 days, it has a compressive strength of at least 1400 psi as tested according to ASTM C39.
摘要:
Disclosed is a method and apparatus for spray application of a monolithic refractory material, designed to add water to a powder material and knead the powder material during feeding. In the method and apparatus, a primary water injector 7 is arranged in a feed hose 5 extending from a spray-material supply device 1 to a distal spray nozzle 4, and a secondary water injector 8 is arranged in the feed hose at a position just before the distal spray nozzle 4. The primary water injector 7 is arranged on an upstream side of the secondary water injector 8 with a given distance therebetween. 10 to 50 mass %, preferably 15 to 40 mass %, of application water on the basis of the total application water required for the spray application is added from the primary water injector together with compression air in the form of water particles having an average particle size of 100 μm or less, to evenly wet a spray material during feeding to the extent capable of preventing the spray material from being slurried. Then, the remaining application water is injected from the secondary water injector together with compression air. The spray application method and apparatus of the present invention can achieve a high kneading effect by a low amount of application water while improving operational efficiency.
摘要:
A lightweight concrete composition containing from 10 to 90 volume percent of a cement composition, from 10 to 90 volume percent of particles having an average particle diameter of from 0.2 mm to 8 mm, a bulk density of from 0.03 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3, and from 0 to 50 volume percent of aggregate; where the sum of components used does not exceed 100 volume percent, and where after the lightweight concrete composition is set it has a compressive strength of at least 1700 psi as tested according to ASTM C39 after seven days. The concrete composition can be used to make concrete masonry units, construction panels, road beds and other articles.