# US 9,434,826 B2 · Graphene-augmented carbon fiber for aerospace composites > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,434,826 B2 - Document ID: US9434826B2 - Status: Granted - Kind: B2 - Application number: 14/589,057 - Filed: 2015-01-05 - Published: 2016-07-07 - Granted: 2016-09-06 - Earliest claimed: 2015-01-05 - Assignees: The Boeing Company - Applicants: The Boeing Company - Inventors: Keith Daniel Humfeld - Web page: https://patentgrep.com/patent/US9434826B2 ## CPC - C08J 5/06: using pretreated fibrous materials - C01B 32/182: Graphene - C01B 32/194: After-treatment - C08J 5/042: {with carbon fibres} - C08J 5/248: {using pre-treated fibres} - C08K 7/06: Elements - D01F 9/12: Carbon filaments; Apparatus specially adapted for the manufacture thereof - D02G 3/38: Threads in which fibres, filaments, or yarns are wound with other yarns or filaments, {e.g. wrap yarns, i.e. strands of filaments or staple fibres are wrapped by a helically wound binder yarn; (D02G3/32 takes precedence)}; (covering endless core threads with fibres by using open-end spinning techniques D01H4/00) - C08J 2300/00: Characterised by the use of unspecified polymers - D10B 2101/12: Carbon; Pitch - D10B 2505/02: Reinforcing materials; Prepregs - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C} - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - D01F: CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS - D02G: CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS - D10B: INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES ## Abstract Composite materials with graphene-augmented carbon reinforcement fibers having a graphene film wrapped about one or more carbon fiber filaments. The graphene film is wrapped about the carbon fiber filaments in a spiral orientation and has amine groups formed on an outer surface of the graphene film and epoxide groups formed on at least one edge of the graphene film. The amine groups are formed in a functionalized area on the outer surface of the graphene film that is within about 10 microns from the at least one edge of the graphene film. The graphene film may also have holes formed through the graphene film. The graphene film may be wrapped around a single carbon fiber filament, a substantially cylindrical bundle of about 19 carbon fiber filaments, or a substantially rectangular bed of carbon fiber filaments formed from a plurality of carbon fiber tows. ## Claims ### Claim 1 A graphene-augmented carbon fiber comprising a graphene film wrapped about a carbon fiber filament. ### Claim 2 (depends on 1) The graphene-augmented carbon fiber of claim 1, wherein the graphene film is wrapped about the carbon fiber filament in a spiral orientation. ### Claim 3 (depends on 2) The graphene-augmented carbon fiber of claim 2, wherein the graphene film is wrapped about the carbon fiber filament to a thickness of about 0.1 to about 3.0 microns to form about 300 to about 9,000 layers of the graphene film on top of the carbon fiber filament. ### Claim 4 (depends on 1) The graphene-augmented carbon fiber of claim 1, wherein the graphene film has amine groups formed on an outer surface of the graphene film and epoxide groups formed on at least one edge of the graphene film. ### Claim 5 (depends on 4) The graphene-augmented carbon fiber of claim 4, wherein the amine groups are formed in a functionalized area on the outer surface of the graphene film that is within about 10 microns from the at least one edge of the graphene film. ### Claim 6 (depends on 5) The graphene-augmented carbon fiber of claim 5, wherein the amine groups in the functionalized area on the outer surface of the graphene film have a surface density of about 4.0E10 to about 2.0E12 groups per square millimeter of the functionalized area. ### Claim 7 (depends on 5) The graphene-augmented carbon fiber of claim 5, wherein about 0.1% to about 5.0% of carbon atoms in the functionalized area of the graphene film have amine groups bonded thereto. ### Claim 8 (depends on 4) The graphene-augmented carbon fiber of claim 4, wherein the graphene film has a linear density of epoxide groups formed on the at least one edge of about 7,000 to about 700,000 groups per millimeter. ### Claim 9 (depends on 4) The graphene-augmented carbon fiber of claim 4, wherein about 0.1% to about 10% of carbon atoms at the least one edge of the graphene film have epoxide groups bonded thereto. ### Claim 10 (depends on 1) The graphene-augmented carbon fiber of claim 1, wherein the graphene film is about 0.5 microns to about 100 microns wide. ### Claim 11 (depends on 4) The graphene-augmented carbon fiber of claim 4, wherein the graphene film further comprises at least one hole formed through the graphene film. ### Claim 12 (depends on 11) The graphene-augmented carbon fiber of claim 11, wherein the holes are substantially circular and have a diameter of 1-2 nanometers. ### Claim 13 (depends on 11) The graphene-augmented carbon fiber of claim 11, wherein the graphene film has a density of holes in the range of about 4E7 to about 4E10 holes per square millimeter, or about one hole per 1,000 to 1 million carbon atoms. ### Claim 14 (depends on 11) The graphene-augmented carbon fiber of claim 11, wherein the holes have a size of about 12-80 carbon atoms. ### Claim 15 (depends on 1) The graphene-augmented carbon fiber of claim 1, wherein the graphene film is wrapped around a substantially cylindrical bundle of at least one of 7, 19, 37 or 61 carbon fiber filaments. ### Claim 16 (depends on 15) The graphene-augmented carbon fiber of claim 15, wherein the graphene film is about 0.5 microns to about 10 microns wide. ### Claim 17 (depends on 15) The graphene-augmented carbon fiber of claim 15, wherein the graphene film comprises holes formed through the graphene film. ### Claim 18 (depends on 17) The graphene-augmented carbon fiber of claim 17, wherein the holes are substantially circular and have a diameter of 1-20 nanometers. ### Claim 19 (depends on 17) The graphene-augmented carbon fiber of claim 17, wherein the holes have a size of greater than about 100 carbon atoms. ### Claim 20 (depends on 19) The graphene-augmented carbon fiber of claim 19, wherein the graphene film has a density of holes in the range of about 4E7 to about 4E10 holes per square millimeter, or about one hole per 1,000 to 1 million carbon atoms. ### Claim 21 (depends on 17) The graphene-augmented carbon fiber of claim 17, wherein the graphene film is wrapped about the substantially cylindrical bundle of at least one of 7, 19, 37 or 61 carbon fiber filaments in a spiral orientation. ### Claim 22 (depends on 21) The graphene-augmented carbon fiber of claim 21, wherein the graphene film is wrapped about the cylindrical bundle of at least one of 7, 19, 37 or 61 carbon fiber filaments to a thickness of about 0.1 to about 3.0 microns to form about 300 to about 9,000 layers of the graphene film on top of the carbon fiber filaments. ### Claim 23 (depends on 17) The graphene-augmented carbon fiber of claim 17, wherein the graphene film has amine groups formed on an outer surface of the graphene film and epoxide groups formed on at least one edge of the graphene film. ### Claim 24 (depends on 23) The graphene-augmented carbon fiber of claim 23, wherein the amine groups are formed in a functionalized area on the outer surface of the graphene film that is within about 10 microns from the at least one edge of the graphene film. ### Claim 25 A graphene-augmented bed of carbon fiber, comprising a graphene film wrapped around a substantially rectangular bed of carbon fiber filaments separated from a plurality of carbon fiber tows. ### Claim 26 (depends on 25) The graphene-augmented bed of carbon fiber of claim 25, wherein the substantially rectangular bed of carbon fiber filaments is about 12 inches wide and about 250 microns thick. ### Claim 27 (depends on 25) The graphene-augmented bed of carbon fiber of claim 25, wherein the substantially rectangular bed of carbon fiber filaments comprises about 600,000 of the carbon fiber filaments. ### Claim 28 (depends on 25) The graphene-augmented bed of carbon fiber of claim 25, wherein the graphene film is about 0.5 microns to about 100 microns wide. ### Claim 29 (depends on 25) The graphene-augmented bed of carbon fiber of claim 25, wherein the graphene film comprises substantially circular holes formed through the graphene film having a diameter of 1-20 nanometers. ### Claim 30 (depends on 29) The graphene-augmented bed of carbon fiber of claim 29, wherein the graphene film has a density of holes in the range of about 4E7 to about 4E10 holes per square millimeter, or about one hole per 1,000 to 1 million carbon atoms. ### Claim 31 (depends on 25) The graphene-augmented bed of carbon fiber of claim 25, wherein the graphene film is wrapped about the rectangular bed of carbon fiber filaments in a spiral orientation. ### Claim 32 (depends on 31) The graphene-augmented bed of carbon fiber of claim 31, wherein the graphene film is wrapped about the rectangular bed of carbon fiber filaments to a thickness of about 0.1 to about 3.0 microns to form about 300 to about 9,000 layers of the graphene film on top of the carbon fiber filaments. ### Claim 33 (depends on 29) The graphene-augmented bed of carbon fiber of claim 29, wherein the graphene film has amine groups formed on an outer surface of the graphene film and epoxide groups formed on at least one edge of the graphene film. ### Claim 34 (depends on 33) The graphene-augmented bed of carbon fiber of claim 33, wherein the amine groups are formed in a functionalized area on the outer surface of the graphene film that is within about 10 microns from the at least one edge of the graphene film. ### Claim 35 (depends on 1) A composite material comprising the graphene-augmented carbon fiber of claim 1 and a matrix material. ### Claim 36 (depends on 15) A composite material comprising the graphene-augmented carbon fiber of claim 15 and a matrix material. ### Claim 37 (depends on 25) A composite material comprising the graphene-augmented carbon fiber of claim 25 and a matrix material. ### Claim 38 A method of increasing strength of a composite material comprising carbon reinforcement fibers and a resin matrix material, the method comprising: wrapping a graphene film about each of the carbon reinforcement fibers in a spiral orientation to form graphene-augmented carbon fibers; combining the resin matrix material with a plurality of the graphene-augmented carbon fibers to form a prepreg material; and curing the prepreg material to form the composite material. ### Claim 39 (depends on 38) The method of claim 38, wherein each of the carbon reinforcement fibers in the graphene-augmented carbon fibers comprises a carbon fiber filament. ### Claim 40 (depends on 38) The method of claim 38, wherein each of the carbon reinforcement fibers in the graphene-augmented carbon fibers comprises a substantially cylindrical bundle of at least one of 7, 19, 37 or 61 carbon fiber filaments. ### Claim 41 (depends on 38) The method of claim 38, wherein each of the carbon reinforcement fibers in the graphene-augmented carbon fibers comprises a substantially rectangular bed of carbon fiber filaments separated from a plurality of carbon fiber tows. ### Claim 42 (depends on 38) The method of claim 38, further comprising forming amine groups on an outer surface of the graphene film and epoxide groups on at least one edge of the graphene film. ### Claim 43 (depends on 42) The method of claim 42, wherein the amine groups are formed on the outer surface of the graphene film in a functionalized area that is within about 10 microns from the at least one edge of the graphene film. ### Claim 44 (depends on 38) The method of claim 38, wherein the graphene film is wrapped about the carbon reinforcement fibers to a thickness of about 0.1 to about 3.0 microns to form about 300 to about 9,000 layers of the graphene film on top of the carbon fiber. ### Claim 45 (depends on 38) The method of claim 38, further comprising forming holes through the graphene film having a substantially circular shape and a diameter of 1-20 nanometers. ### Claim 46 (depends on 45) The method of claim 45, wherein the graphene film has a density of holes in the range of about 4E7 to about 4E10 holes per square millimeter, or about one hole per 1,000 to 1 million carbon atoms. ### Claim 47 (depends on 45) The method of claim 45, wherein the step of wrapping a graphene film about each of the carbon reinforcement fibers comprises wrapping the graphene film to a thickness of about 0.1 to about 3.0 microns to form about 300 to about 9,000 layers of the graphene film on top of the bed of carbon reinforcement fibers.