Composition For Contact With Hot Propulsion Or Exhaust Gas Or Process Of Preparing Patents (Class 523/138)
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Patent number: 11306683Abstract: A precursor composition comprising, before curing, ethylene propylene diene monomer (EPDM), zinc oxide, silica, polymerized 1,2-dihydro-2,2,4-trimethylquinoline, a solid chlorinated paraffin, stearic acid, a five carbon petroleum hydrocarbon, trimethylolpropane trimethacrylate, and a peroxide. A rocket motor including a reaction product of the precursor composition and a method of insulating a rocket motor.Type: GrantFiled: March 4, 2020Date of Patent: April 19, 2022Assignee: Northrop Grumman Systems CorporationInventors: Himansu M. Gajiwala, Steven B. Hall
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Publication number: 20120003133Abstract: A method of controlling air pollution arising from sulphur trioxide and or sulphuric acid in coal combustion gases, combustion gases passing through the demister region of a wet flue gas desulphurisation unit are exposed to a sulphide based reducing agent such as hydrogen sulphide, such that metal catalysts promoting the oxidation of ammonia leading to the formation of nitrosylsulfuric acid are poisoned and so prevented from catalysing the formation and discharge of sulphuric acid in aerosol emissions in stack gases.Type: ApplicationFiled: June 23, 2011Publication date: January 5, 2012Inventor: Peter John Hurley
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Patent number: 7968620Abstract: An insulation composition that comprises at least one nitrile butadiene rubber, basalt fibers, and nanoclay is disclosed. Further disclosed is an insulation composition that comprises polybenzimidazole fibers, basalt fibers, and nanoclay. The basalt fibers may be present in the insulation compositions in a range of from approximately 1% by weight to approximately 6% by weight of the total weight of the insulation composition. The nanoclay may be present in the insulation compositions in a range of from approximately 5% by weight to approximately 10% by weight of the total weight of the insulation composition. Rocket motors including the insulation compositions and methods of insulating a rocket motor are also disclosed.Type: GrantFiled: April 22, 2010Date of Patent: June 28, 2011Assignee: Alliant Techsystems Inc.Inventor: Himansu M. Gajiwala
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Publication number: 20090137700Abstract: An insulation material comprising a low-density EPDM polymer, at least one flame-retardant, and an organic filler. The insulation material is used in an insulation layer of a rocket motor. The organic filler is a polymeric, organic filler such as polyvinyl chloride. A rocket motor comprising an insulation material is also disclosed. The insulation material comprises a low-density EPDM polymer, at least one flame-retardant, and a polymeric, organic filler and is applied between an inner surface of a case of the rocket motor and a propellant. A method of insulating a rocket motor is also disclosed.Type: ApplicationFiled: December 5, 2008Publication date: May 28, 2009Applicant: Alliant Techsystems Inc.Inventor: Himansu M. Gajiwala
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Patent number: 7470729Abstract: A method of forming articles made of an inorganic fiber material using compression molding. In one respect, a method of forming an article, wherein the method includes providing a molding composition comprising inorganic fiber and an inorganic binder, and compression molding the molding composition into the article. In another respect, the method including providing a molding composition comprising inorganic fibers and a binder, and compression molding the molding composition into the article, wherein at least 75% by weight of the molded article is inorganic material. In some embodiments the cured binder is capable of withstanding temperatures of at least 600° F. without significant degradation or deterioration due to heat. Articles made by the use of such methods and a molding composition for use in compression molding an article are also included.Type: GrantFiled: January 11, 2005Date of Patent: December 30, 2008Assignee: HNI Technologies Inc.Inventors: David Charles Lyons, Ted Victor Schroeder
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Patent number: 7461503Abstract: An insulation material comprising a low-density EPDM polymer, at least one flame-retardant, and an organic filler. The insulation material is used in an insulation layer of a rocket motor. The organic filler is a polymeric, organic filler such as polyvinyl chloride. A rocket motor comprising an insulation material is also disclosed. The insulation material comprises a low-density EPDM polymer, at least one flame-retardant, and a polymeric, organic filler and is applied between an inner surface of a case of the rocket motor and a propellant. A method of insulating a rocket motor is also disclosed.Type: GrantFiled: June 26, 2003Date of Patent: December 9, 2008Assignee: Alliant Techsystems Inc.Inventor: Himansu M. Gajiwala
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Patent number: 7371784Abstract: A novel and improved EPDM formulation for a solid propellant rocket motor is described wherein hexadiene EPDM monomer components are replaced by alkylidene norbornene components, and, with appropriate adjustment of curing and other additives, functionally required rheological and physical characteristics are achieved with the desired compatibility with any one of a plurality of solid filler materials, e.g., powder silica, carbon fibers or aramid fibers, and with appropriate adhesion and extended storage or shelf-life characteristics.Type: GrantFiled: August 31, 2004Date of Patent: May 13, 2008Assignee: Alliant Techsystems Inc.Inventors: David G. Guillot, Albert R. Harvey
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Patent number: 7012107Abstract: A rocket motor insulation including an elastomer-based polymer is improved in its processability by the addition of silica particles treated with a hydrophobic coating. The insulation also preferably includes a metallic coagent cross-linker, which when used in combination with the hydrophobic silica particles increases the tear strength and the elasticity of the insulation, while at the same time not adversely affecting the bonding characteristics of the insulation.Type: GrantFiled: June 17, 2003Date of Patent: March 14, 2006Assignee: Alliant Techsystems Inc.Inventors: Albert R. Harvey, John W. Ellertson
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Patent number: 6787586Abstract: A novel and improved EPDM formulation for a solid propellant rocket motor is described wherein hexadiene EPDM monomer components are replaced by alkylidene norbornene components, and, with appropriate adjustment of curing and other additives, functionally required rheological and physical characteristics are achieved with the desired compatibility with any one of a plurality of solid filler materials, e.g., powder silica, carbon fibers or aramid fibers, and with appropriate adhesion and extended storage or shelf-life characteristics.Type: GrantFiled: December 3, 2002Date of Patent: September 7, 2004Assignee: Alliant Techsystems Inc.Inventors: David G. Guillot, Albert R. Harvey
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Publication number: 20030220417Abstract: A novel and improved EPDM formulation for a solid propellant rocket motor is described wherein hexadiene EPDM monomer components are replaced by alkylidene norbornene components and with appropriate adjustment of curing and other additives functionally-required rheological and physical characteristics are achieved with the desired compatibility with any one of a plurality of solid filler materials, e.g. powder silica, carbon fibers or aramid fibers, and with appropriate adhesion and extended storage or shelf life characteristics.Type: ApplicationFiled: December 3, 2002Publication date: November 27, 2003Inventors: David G. Guillot, Albert R. Harvey
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Publication number: 20030213228Abstract: A rocket motor insulation including an elastomer-based polymer is improved in its processability by the addition of silica particles treated with a hydrophobic coating. The insulation also preferably includes a metallic coagent cross-linker, which when used in combination with the hydrophobic silica particles increases the tear strength and the elasticity of the insulation, while at the same time not adversely affecting the bonding characteristics of the insulation.Type: ApplicationFiled: June 17, 2003Publication date: November 20, 2003Inventors: Albert R. Harvey, John W. Ellertson
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Publication number: 20030185725Abstract: A holding material for a catalytic converter includes a catalyst carrier, a metal casing for receiving the catalyst carrier, and a holding material interposed in a gap between the catalyst carrier and the metal casing while wound on the catalyst carrier. The holding material is constituted by a molding of inorganic fiber molded with fibrillated fiber into a predetermined shape.Type: ApplicationFiled: March 31, 2003Publication date: October 2, 2003Inventors: Mituru Mutou, Osamu Ishikawa, Hideki Nokura, Toshiyuki Anji, Masafumi Tanaka, Tadashi Sakane, Takahito Mochida
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Patent number: 6606852Abstract: A rocket motor insulation including an elastomer base polymer is improved in its processability by the addition of silica particles treated with a hydrophobic coating. The insulation also preferably includes a metallic coagent cross-linker, which when used in combination with the hydrophobic silica particles increases the tear strength and the elasticity of the insulation, while at the same time not adversely affecting the bonding characteristics of the insulation.Type: GrantFiled: July 11, 2000Date of Patent: August 19, 2003Assignee: Alliant Techsystems Inc.Inventors: Albert R. Harvey, John W. Ellertson
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Patent number: 6566420Abstract: A novel and improved EPDM formulation for a solid propellant rocket motor is described wherein hexadiene EPDM monomer components are replaced by alkylidene norbornene components and with appropriate adjustment of curing and other additives functionally-required rheological and physical characteristics are achieved with the desired compatibility with any one of a plurality of solid filler materials, e.g. powder silica, carbon fibers or aramid fibers, and with appropriate adhesion and extended storage or shelf life characteristics.Type: GrantFiled: January 12, 2000Date of Patent: May 20, 2003Assignee: Alliant Techsystems Inc.Inventors: David G. Guillot, Albert R. Harvey
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Patent number: 6554936Abstract: An elastomerized phenolic resin ablative insulation particularly suitable for use in connection with the thermal insulation of selected components of rocket motors. A composition for making the elastomerized ablative insulation is disclosed. Furthermore, an associated method of forming calendered sheets of material formed of the composition is disclosed. The preferred ingredients of the disclosed composition include acrylonitryle butadiene rubber, zinc borate, and phenol formaldehyde resin which can be cured and bonded to structures such as domes of open-ended rocket motors and other rocket motor components. The subject elastomerized ablative insulation is well suited for use independently or in connection with other insulative materials to form a thermal barrier which is highly resistant to the heat and the erosive nature associated with the combustion of propellant fuels, for example.Type: GrantFiled: September 8, 1999Date of Patent: April 29, 2003Assignee: Alliant Techsystems Inc.Inventors: Gary S. Metcalf, William E. White
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Patent number: 6548570Abstract: A radiation shielding material is manufactured from an elastomer that is blended with a radiation-absorbing filler material. The filler material comprises a powder of a metal with a high atomic member, or compounds thereof. The filler material is represented by more than 80 percent weight and has a grain size distribution in the range of 20 &mgr;m to 120 &mgr;m. The filler material is mixed with a loading material in powdered form. That mixture is kneaded with the elastomer within a mixer while the temperature is maintained below 180° C. The kneaded mixture is cooled and then cut into strips. The strips are passed through a strainer having a mesh width of between 5 &mgr;m and 1000 &mgr;m. The strained strips are then formed into a foil.Type: GrantFiled: November 16, 2000Date of Patent: April 15, 2003Assignee: Arntz Beteiligungs GmbH & Co. KGInventor: Wolfgang Lange
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Patent number: 6054521Abstract: The present invention concerns an erosion resistant, low signature liner for solid propellant rocket motors and rocket motors having such a low signature liner. The liner combustion products in the exhaust plume have low visibility in the IR and visible light spectra which is essential for use in low signature solid propellant rocket motors. The liner also forms an in-situ protective layer at elevated temperatures for enhanced erosion resistance. These erosion resistant properties eliminate the need for supplemental case insulation which would contribute additional smoke and combustion products to the exhaust plume as well as add additional costs and inert weight to the motor.Type: GrantFiled: December 8, 1997Date of Patent: April 25, 2000Assignee: Cordant Technologies Inc.Inventors: Ronald W. Nelson, Merylin B. Lovett, Larry W. Poulter, Elizabeth K. Bonderson
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Patent number: 5905101Abstract: The invention relates to an ablator composition for providing ablation protection after cure thereof. The. ablator composition includes the components of: (A) 100 parts by weight of a silicone elastomer composition which is curable to a silicone elastomer by addition reaction; (B) 50-200 parts by weight of an amorphous silica having an average diameter from 0.1 to 100 .mu.m; and (C) 1-15 parts by weight of a first fiber having an average length from 0.5 to 6 mm in a longitudinal direction thereof and an average diameter from 1 to 20 .mu.m. The first fiber is at least one of a carbon fiber and a synthetic quartz fiber. An ablating material prepared by curing the ablator composition is superior in heat insulation and substantially low in ablation rate, and thus protects a spacecraft or the like from a high temperature gas, for a long time.Type: GrantFiled: March 19, 1996Date of Patent: May 18, 1999Assignees: Nissan Motor Co., Ltd., Shin-Etsu Chemical Co., Ltd.Inventors: Hironao Fujiki, Morio Ohashi, Hisao Okamoto
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Patent number: 5830384Abstract: The cool insulator incorporates a water gel coolant and poly-p-ethylene tphthalamide fibers (Kevlar) in an elastomeric rubber binder selected from the group consisting of silicon rubber, ethylene-propylene-diene-monomer, polybutadiene, and polyisoprene. The fiber provides erosion resistance required for long motor burning periods. This insulation includes a submicroscopic particulate water source with high temperature water release properties. The submicroscopic particulate water source is in the form of a flowable solid when formulated and in a weight percent amount from about 10 to about 20. The preferred water source is submicroscopic particulate silica containing over 11.times.10.sup.15 particles per gram and has a surface area of about 200 square meters per gram. The submicroscopic particulate silica is known as "dry water" and specifically described by its method of preparation in commonly assigned U.S. Pat. No. 4,008,170.Type: GrantFiled: June 30, 1997Date of Patent: November 3, 1998Assignee: The United States of America as represented by the Secretary of the ArmyInventors: William D. Stephens, Christi L. Salter, Gregory K. Hodges, Terry E. Hice, Jonathon S. Prickett
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Patent number: 5821284Abstract: Provided is an insulation for rocket motors that uses two ingredients not previously combined in such insulation before. These ingredients are ammonium sulfate and antimony oxide, which when combined, have a synergistic effect that reduces the ablation rate significantly. Such insulation also includes EPDM rubber and aramid fibers. The inventive insulation also exhibits better tear resistance and propellant-to-insulation bond peel strength, compared with prior art rocket motor insulation.Type: GrantFiled: October 27, 1995Date of Patent: October 13, 1998Assignee: The United States of America as represented by the Secretary of the Air ForceInventors: Mark Graham, Lane Levi, Brett Clarke
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Patent number: 5762746Abstract: A composition consisting essentially of a polyphosphazene binder having the following repeating units: ##STR1## wherein n is from about 20 to about 50,000, A is selected from --O-- and --NH--, and R.sup.1 and R.sup.2 are independently selected from alkyl having from one to about 20 carbon atoms, aryl having from 6 to about 14 carbon atoms, alkaryl having from 7 to about 30 carbon atoms, any of the preceding moieties substituted with halogen, hydroxyl, alkoxy, aryloxy, or nitro groups, or any of the preceding moieties linked by ether or amine linkages. Combined with an organic fiber filler, this material provides an erosion resistant insulation composition for temporarily protecting the interior of a rocket motor combustion chamber from thermal damage while the rocket is firing.Type: GrantFiled: August 16, 1989Date of Patent: June 9, 1998Assignee: Thiokol CorporationInventors: James A. Hartwell, Dale E. Hutchens, Kenneth E. Junior, James D. Byrd
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Patent number: 5352312Abstract: Rocket motor insulation compositions are provided. An important component of such insulation compositions is a thermoplastic liquid crystal polymer. Such a polymer provides an ablative insulation which has good performance characteristics during operation of the rocket motor. One such thermoplastic liquid crystal polymer is a wholly aromatic polyester known as VECTRA.RTM.. The insulation may also include fillers such as fibrous fillers and particulate fillers. Typical fibrous fillers include glass or carbon fibers. Typical particulate fillers include materials such as silica, alumina, powdered coal, and the like.Type: GrantFiled: August 6, 1992Date of Patent: October 4, 1994Assignee: Thiokol CorporationInventor: David G. Guillot
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Patent number: 5340643Abstract: Intumescent sheets are having improved expansion characteristics are disclosed. The intumescent sheets comprise an inorganic fibrous material, a binder, and a heat expandable layer mineral composition containing at least 87.5% by weight of heat expandable interstratified layer minerals comprising interstratified layers of vermiculite and biotite.Type: GrantFiled: February 26, 1993Date of Patent: August 23, 1994Assignee: W. R. Grace & Co.-Conn.Inventors: Chia-Chih Ou, Leon Bablouzian
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Patent number: 5254410Abstract: Intumescent vermiculite flakes useful in mountings of catalytic converters are prepared by partially dehydrating vermiculite ore to afford a uniform content of chemically bound water from about 1.0 to 3.2% by weight and a uniform bulk density from about 0.2 to 0.9 g/cm.sup.3. Such a mounting affords good support to the monolith at warm-up temperatures, exerts adequate holding forces at operating temperatures without danger of cracking the monolith, and does not incur gradual reduction in holding forces at operating temperatures. The mounting layer can be applied as either a mat or a paste.Type: GrantFiled: April 18, 1991Date of Patent: October 19, 1993Assignee: Minnesota Mining & Manufacturing CompanyInventors: Roger L. Langer, Richard P. Merry
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Patent number: 5110502Abstract: A solution for suppressing the formation of contrails from the exhaust of an engine including by weight between about 0.01% to 2.5% of the non-corrosive surfactant, between about 1% and 8% water, and between about 85% and 99% ethylene glycol. Another solution may include by weight a monohydric, dihydric or polyhydric alcohol in an amount of between about 85% and 99% and the non-corrosive surfactant in an amount of between about 0.01% and 8%. Still another solution may include an inorganic nucleating or hygroscopic salt, such as ammonium iodide, ammonium fluoride, silver iodide or calcium chloride in monohydric, dihydric or polyhydric alcohols and surfactant mixtures. Yet another solution may include an inorganic salt in monohydric, dihydric or polyhydric alcohols.Type: GrantFiled: August 22, 1988Date of Patent: May 5, 1992Assignee: SCIPAR, Inc.Inventor: Surjit Singh
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Patent number: 5047449Abstract: This material, essentially characterized in that it is flexible, employs simultaneously the two phenomena of in tumescence and endothermicity to obtain optimal protection characteristics maintaining the element to be protected at a temperature below or in the order of 150.degree. C. when it is subjected to thermal attack corresponding to a flame temperature of 700.degree. to 1000.degree. for a duration of at least one hour for a thickness of the material between 10 and 20 mm, comprises a binder (silicone elastomer) in a proportion of 30 to 35% by weight; a reinforcing charge (a metal oxide compatible with said silicone elastomer) in a proportion of 17 to 23% by weight; an active charge (an intumescent agent) in a production of 38 to 45% by weight; and an insulative charge in a proportion of 5 to 10% by weight, these proportions being relative to the total weight of said material.Type: GrantFiled: June 15, 1989Date of Patent: September 10, 1991Assignee: Aerospatiale Society National IndustrielleInventor: Nicole Pastureau
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Patent number: 4956397Abstract: An improved composition for an insulating liner, or insuliner, for a solid propellant rocket motor, which composition comprises a vulcanizable elastomeric composition comprising a vulcanizable elastomer and about 5 to 25 pph (parts by weight per 100 parts by weight of elastomer) of vulcanizing agents for the elastomer, about 10 to 20 pph of aramid polymer fibers, about 5 to 20 pph of a powder filler selected from the group consisting of silica, iron oxide, titanium dioxide, carbon, milled glass and ceramic clays, and about 10 to 25 pph of a bond promoter selected from the group consisting of treated cellulosic fiber and a multifunctional aromatic epoxy resin.Type: GrantFiled: July 17, 1989Date of Patent: September 11, 1990Assignee: The United States of America as represented by the Secretary of the Air ForceInventors: Gregory S. Rogowski, Thomas F. Davidson, Timothy Ludlow
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Patent number: 4878431Abstract: Non-asbestos elastomeric insulating materials for rocket motors are disclosed. The insulating materials are low in density (between about 0.035 and 0.050 lb./cubic inch) and comprise crosslinked elastomeric polymers (100 parts by weight of a crosslinkable elastomeric polymer that is substantially saturated and about 5-50 parts by weight of a crosslinkable, substantially unsaturated, elastomeric polymer) in which are dispersed between about 10 and 100 (preferably 15-75) parts by weight of a char forming organic fiber selected from polyaramide pulps, between 1 and 15 parts by weight of a peroxide crosslinker, and between about 0 and 150 parts by weight organic and/or inorganic particulate. The insulating materials issue little smoke, have notable erosion resistance and can be tailored to have thermal, mechanical and other properties of desired character. Ingredients such as supplemental elastomers, oils and lubricants enhance the processability and green properties such as tack of the insulating materials.Type: GrantFiled: February 21, 1986Date of Patent: November 7, 1989Assignee: Hercules IncorporatedInventor: Liles G. Herring
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Patent number: 4766725Abstract: A method of suppressing the formation of contrails from the exhaust of an engine including the steps of providing a solution of a non-corrosive surfactant in a combined carrier and nucleating agent selected from the group of water soluble monohydric, dihydric, trihydric or other polyhydric alcohols, forming the solution into a vapor, and injecting the solution into the exhaust of the engine. The solution may include by weight between about 0.01% to 2.5% of the non-corrosive surfactant, between about 1% and 8% water, and between about 85% and 99% ethylene glycol. Another solution may include by weight a monohydric, dihydric or polyhydric alcohol in an amount of between about 85% and 99% and the non-corrosive surfactant in an amount of between about 0.01% and 8%. Still another solution may include an inorganic nucleating or hygroscopic salt, such as ammonium iodide, ammonium fluoride, silver iodide or calcium chloride in monohydric, dihydric or polyhydric alcohols and surfactant mixtures.Type: GrantFiled: December 24, 1985Date of Patent: August 30, 1988Assignee: Scipar, Inc.Inventor: Surjit Singh
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Patent number: 4706912Abstract: A structural external insulation for hypersonic missiles which reach speeds hat cause surface temperatures on the cylindrical shell structure to reach up to 3000.degree. F. for a period of time. The invention incorporates efficient high temperature insulation as an integral part of the composite shell manufacturing process (tape layup and/or filament winding).Type: GrantFiled: December 16, 1985Date of Patent: November 17, 1987Assignee: The United States of America as represented by the Secretary of the ArmyInventor: John S. Perry
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Patent number: 4600732Abstract: An elastomeric composition suitable for use as a rocket motor case insulation is disclosed. The composition comprises a vulcanizable elastomeric material and reinforcing polybenzimidazole polymer fibers in combination with a powder filler. A preferred embodiment utilizes polyisoprene as the elastomer and silica as the powder filler. These compositions have better erosion resistance than asbestos-reinforced compositions, and do not pose the environmental or safety risks associated with asbestos-reinforced insulation.Type: GrantFiled: December 16, 1983Date of Patent: July 15, 1986Assignee: Thiokol CorporationInventors: Kenneth E. Junior, James D. Byrd, James O. Hightower, Jr.
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Patent number: 4515912Abstract: Cure shrink-resistant missile motor cases are disclosed along with their method for construction. These cases comprise a matrix resin composition which includes a bisspiroortho carbonate as a fourth component, a curing agent of o-phenylenediamine boron trifluoride etherate as a third component, butanediol diglycidyl ether as a second component, and equal parts by weight of diglycidyl ether of bisphenol A and epoxidized dimer of oleic acid as a second component and additionally, they comprise, in combination therewith, a high strength fiber reinforcement material selected from the group consisting of fibers of glass, graphite, and poly-p-ethylene terephthalamide (Kevlar). The specific bisspiroortho carbonate which achieves an expansion of the matrix resin on polymerization or curing is 3,9-bis(5'-norbornene-2'-yl)-1,5,7,11-tetraoxaspiro [5.5]undecane.Type: GrantFiled: July 5, 1984Date of Patent: May 7, 1985Assignee: The United States of America as represented by the Secretary of the ArmyInventor: David C. Sayles
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Patent number: 4514541Abstract: A particulate elastomeric composition having a density ratio of 0.1 to 0.4 comprising 5-75% by weight of an elastomer, 15-65% by weight of a filler and 10-60% by weight of aramid pulp and a solution process for its preparation. The composition is useful as a masterbatch for the introduction of aramid pulp into elastomeric articles.Type: GrantFiled: May 21, 1984Date of Patent: April 30, 1985Assignee: E. I. Du Pont de Nemours and CompanyInventor: Arnold Frances
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Patent number: 4492779Abstract: An elastomeric composition suitable for use as a rocket motor case insulation is disclosed. The composition consists of a vulcanizable elastomeric composition and reinforcing aramid polymer fibers in combination with a powder filler. A preferred embodiment utilizes polyisoprene as the elastomer, KELVAR.RTM. fibers as the aramid polymer fibers, and silica as the powder filler.Type: GrantFiled: December 7, 1981Date of Patent: January 8, 1985Assignee: Thiokol CorporationInventors: Kenneth E. Junior, James D. Byrd
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Patent number: 4385135Abstract: Flexible intumescent sheet materials containing low density filler components to provide low density mounting mats which reduce the mount density to prevent ceramic diesel particulate monolith cracking are disclosed.Type: GrantFiled: May 26, 1982Date of Patent: May 24, 1983Assignee: Minnesota Mining and Manufacturing CompanyInventors: Roger L. Langer, Alan J. Marlor