# US 11,306,683 B2 · Precursor compositions for an insulation and insulated rocket motors > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,683 B2 - Document ID: US11306683B2 - Status: Granted - Kind: B2 - Application number: 16/809,396 - Filed: 2020-03-04 - Published: 2021-03-18 - Granted: 2022-04-19 - Earliest claimed: 2017-03-16 - Assignees: Northrop Grumman Systems Corporation - Applicants: Northrop Grumman Systems Corporation - Inventors: Himansu M. Gajiwala; Steven B. Hall - Web page: https://patentgrep.com/patent/US11306683B2 ## CPC - F02K 9/346: {Liners, e.g. inhibitors} - B64G 1/40: Arrangements or adaptations of propulsion systems - B64G 1/403: {Solid propellant rocket engines} - C08F 255/06: on to ethylene-propylene-diene terpolymers {(C08F255/023 takes precedence)} - C08K 3/22: of metals - C08K 3/36: Silica - C08K 9/04: Ingredients treated with organic substances {(treated with macromolecular compounds C08K9/08)} - C08K 2003/2296: {of zinc} - C08L 2201/08: Stabilised against heat, light or radiation or oxydation - C08L 2205/06: having improved processability or containing aids for moulding methods - F05D 2220/80: in supersonic vehicles excluding hypersonic vehicles or ram, scram or rocket propulsion - F05D 2230/90: Coating; Surface treatment - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) - B64G: COSMONAUTICS; VEHICLES OR EQUIPMENT THEREFOR - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract 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. ## Claims ### Claim 1 A precursor composition, comprising, before curing: ethylene propylene diene monomer (EPDM), zinc oxide, silica, a solid chlorinated paraffin, an antioxidant, a processing aid, a plasticizer, a coagent, and a curative. ### Claim 2 (depends on 1) The precursor composition of claim 1, wherein the precursor composition comprises from about 4.2 parts by weight to about 9 parts by weight of the solid chlorinated paraffin. ### Claim 3 (depends on 1) The precursor composition of claim 1, wherein the precursor composition comprises from about 2.1 parts by weight to about 4.5 parts by weight of the zinc oxide. ### Claim 4 (depends on 1) The precursor composition of claim 1, wherein the precursor composition comprises from about 21 parts by weight to about 45 parts by weight of the silica. ### Claim 5 (depends on 1) The precursor composition of claim 1, wherein the coagent comprises trimethylolpropane trimethacrylate. ### Claim 6 (depends on 1) The precursor composition of claim 1, wherein the curative comprises a peroxide. ### Claim 7 (depends on 1) The precursor composition of claim 1, wherein the precursor composition comprises less than about 12 parts by weight of the curative. ### Claim 8 A precursor composition, comprising, before curing: ethylene propylene diene monomer (EPDM), zinc oxide, silica, a solid chlorinated paraffin, stearic acid, an antioxidant, a plasticizer, a coagent, and a peroxide. ### Claim 9 (depends on 8) The precursor composition of claim 8, wherein the precursor composition comprises from about 0.35 part by weight to about 0.75 part by weight of the stearic acid. ### Claim 10 (depends on 8) The precursor composition of claim 8, wherein the EPDM comprises a non-conjugated diene and the EPDM comprises a diene content of from about 1% by weight (wt %) to about 10 wt %. ### Claim 11 (depends on 8) The precursor composition of claim 8, wherein the EPDM comprises an ethylene content of between about 40 wt % and about 85 wt %. ### Claim 12 (depends on 9) The precursor composition of claim 9, wherein the antioxidant comprises polymerized 1,2-dihydro-2,2,4-trimethylquinoline. ### Claim 13 (depends on 8) The precursor composition of claim 8, wherein the precursor composition comprises from about 0.35 part by weight to about 0.75 part by weight of the antioxidant. ### Claim 14 (depends on 8) The precursor composition of claim 8, wherein the plasticizer comprises a five carbon petroleum hydrocarbon. ### Claim 15 (depends on 8) The precursor composition of claim 8, wherein the precursor composition comprises from about 4.2 parts by weight to about 9 parts by weight of the plasticizer. ### Claim 16 (depends on 8) The precursor composition of claim 8, wherein the coagent comprises a low volatility trifunctional monomer. ### Claim 17 (depends on 8) The precursor composition of claim 8, wherein the coagent comprises trimethylolpropane trimethacrylate. ### Claim 18 (depends on 8) The precursor composition of claim 8, wherein the precursor composition comprises from about 5.6 parts by weight to about 12 parts by weight of the coagent. ### Claim 19 (depends on 8) The precursor composition of claim 8, wherein the peroxide comprises 1,1-di-(t-butylperoxy)-3,3,5-trimethylcyclohexane. ### Claim 20 (depends on 8) The precursor composition of claim 8, further comprising multiwalled carbon nanotubes. ### Claim 21 A rocket motor, comprising: a case, an insulation on at least a portion of the case, and a propellant in the case, the insulation comprising: a reaction product of ethylene propylene diene monomer (EPDM), zinc oxide, silica, a solid chlorinated paraffin, an antioxidant, a processing aid, a plasticizer, a coagent, and a curative. ### Claim 22 (depends on 1) The precursor composition of claim 1, wherein the antioxidant comprises a hydroquinoline compound and the coagent comprises trimethylolpropane trimethacrylate. ### Claim 23 (depends on 1) The precursor composition of claim 1, wherein the antioxidant comprises polymerized 1,2-dihydro-2,2,4-trimethylquinoline and the coagent comprises trimethylolpropane trimethacrylate.