Method to Massively Manufacture Carbon Fibers through Graphene Composites and the Use Thereof

Abstract

This invention innovates a low cost method to synthesize carbon fibers through graphene composites, which are fabricated through chemical treatment of graphite. This invention also is related to the applications of thereof carbon fibers in different fields. Several examples of such fields would be to use carbon fibers to manufacture carbon fiber tubes, pipes or risers, or car/airplane/computer parts, bicycles, and sports supplies and many additional applications.

Claims

1) A method of forming carbon fibers comprising the steps of: mixing a quantity of graphene oxide in a solvent having a surfactant; adding a polymer to the solvent-graphene oxide mixture; stirring the mixture to reach an approximately uniform viscosity; adding a quantity of nano-cellulose fibers to the mixture; forming fibers from the mixture of graphene oxide, solvent, polymer, and nano-cellulose fibers; and heating the formed fibers in air to a temperature between approximately 200-500 Celsius.

2) The method of claim 1 wherein the step of forming fibers comprises one of wet-drawing plus hot air heating, drying spinning, melt-spinning or solution spinning, and electrical spinning.

3) The method of claim 1 further comprising the step of heating the formed fibers in an inert gas environment to approximately 600-900 Celsius.

4) The method of claim 1 further comprising the step of heating the formed fibers in an inert gas environment to approximately 650 Celsius.

5) The method of claim 1 wherein the step of heating the formed fibers in air comprises heating the formed fibers to approximately 300 Celsius.

6) The method of claim 1 further comprising the step of heating the formed fibers in a hydrogen gas environment to approximately 1500-2000 Celsius.

7) The method of claim 1 further comprising the step of heating the formed fibers in a hydrogen gas environment to approximately 1200 Celsius for two hours.

8) The method of claim 8 further comprising the step of heating the formed fibers in a hydrogen gas environment to approximately 2000 Celsius for two hours after the step of heating the formed fibers to approximately 1200 Celsius for two hours.

9) The method of claim 1 further comprising the step of adding at least one of CuO, NiO, ZrO.sub.2, Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, Co.sub.2O.sub.3, MgO, MnO.sub.2, ZnO, TiO.sub.2, Al.sub.2O.sub.3, SiO.sub.2, AgO, SnO.sub.2, Mo.sub.2O.sub.3, WO.sub.3, Cr.sub.2O.sub.3, trace lanthanum hafnate (La.sub.2Hf.sub.2O.sub.7), IrO.sub.2, metal nanoparticles or nanowires, such as Al, Mg, Ag, Au, Cu, Ni, Co, Zn, Fe, Sn, Ti, Cr, W, Mo, Pt, and Si nanowires to the mixture.

10) The method of claim 1 wherein the polymer is at least one of polyacrylonitrile, polystyrene, components found in asphalt, epoxy, polycarbonate, celluloses, polyvinyl alcohol, polyurethane, polyvinyl chloride, polyethylene, polyethylene glycol, nylon, polydimethylsiloxane, and polyacrylamide.

11) The method of claim 1 wherein the solvent is at least one of water, an alcohol, acetone, a ketone, dimethyl formamide, ethylene glycol, and Dimethyl sulfoxide.

12) The method of claim 1 further comprising forming the formed fibers into a functional shape comprising a plurality of the formed fibers.

13) The method of claim 12 further comprising the step of applying a concrete layer to a surface of the functional shape.

14) The method of claim 12 wherein the functional shape is a vehicle panel.

15) The method of claim 12 wherein the functional shape is a pipe.

16) The method of claim 3 further comprising the step of heating the formed fibers in a hydrogen gas environment to approximately 1500-2000 Celsius.

17) The method of claim 16 further comprising the step of adding at least one of CuO, NiO, ZrO.sub.2, Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, Co.sub.2O.sub.3, MgO, MnO.sub.2, ZnO, TiO.sub.2, Al.sub.2O.sub.3, SiO.sub.2, AgO, SnO.sub.2, Mo.sub.2O.sub.3, WO.sub.3, Cr.sub.2O.sub.3, trace lanthanum hafnate (La.sub.2Hf.sub.2O.sub.7), IrO.sub.2, metal nanoparticles or nanowires, such as Al, Mg, Ag, Au, Cu, Ni, Co, Zn, Fe, Sn, Ti, Cr, W, Mo, Pt, and Si nanowires to the mixture.

18) The method of claim 3 further comprising the steps of heating the formed fibers in a hydrogen gas environment to approximately 1200 Celsius for two hours and then heating the formed fibers in a hydrogen gas environment to approximately 2000 Celsius for two hours.

19) The method of claim 18 further comprising the step of adding at least one of CuO, NiO, ZrO.sub.2, Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, Co.sub.2O.sub.3, MgO, MnO.sub.2, ZnO, TiO.sub.2, Al.sub.2O.sub.3, SiO.sub.2, AgO, SnO.sub.2, Mo.sub.2O.sub.3, WO.sub.3, Cr.sub.2O.sub.3, trace lanthanum hafnate (La.sub.2Hf.sub.2O.sub.7), IrO.sub.2, metal nanoparticles or nanowires, such as Al, Mg, Ag, Au, Cu, Ni, Co, Zn, Fe, Sn, Ti, Cr, W, Mo, Pt, and Si nanowires to the mixture.

20) The method of claim 4 further comprising the steps of adding at least one of CuO, NiO, ZrO.sub.2, Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, Co.sub.2O.sub.3, MgO, MnO.sub.2, ZnO, TiO.sub.2, Al.sub.2O.sub.3, SiO.sub.2, AgO, SnO.sub.2, Mo.sub.2O.sub.3, WO.sub.3, Cr.sub.2O.sub.3, trace lanthanum hafnate (La.sub.2Hf.sub.2O.sub.7), IrO.sub.2, metal nanoparticles or nanowires, such as Al, Mg, Ag, Au, Cu, Ni, Co, Zn, Fe, Sn, Ti, Cr, W, Mo, Pt, and Si nanowires to the mixture; heating the formed fibers in a hydrogen gas environment to approximately 1200 Celsius for two hours; and heating the formed fibers in a hydrogen gas environment to approximately 2000 Celsius for two hours.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The utility method shall be hereby described in detail in the description with reference to the attached drawings, in which:

[0029] FIG. 1 is a flowchart showing a method of manufacturing graphene carbon fiber according to the present invention; and

[0030] FIG. 2 is a flowchart showing another method of manufacturing graphene carbon fiber according to the present invention; and

[0031] FIG. 3 is a flowchart showing yet another method of manufacturing graphene carbon fiber according to the present invention; and

[0032] FIG. 4 is a view showing an embodiment of the carbon composite nanofibers obtained from the present invention;

[0033] FIG. 5 is a view showing an embodiment of the carbon nanofiber composite obtained from the present invention prepared by the electrospinning method.

[0034] FIG. 6 provides a view of Graphene oxide Compounded with a low melting point polymer powder.

[0035] FIG. 7 provides a view of Melt-spun precursor fibers.

[0036] FIG. 8 provides a view of graphene carbon fiber from graphene oxide under the inducing of polymer templating.

[0037] FIG. 9 provides a view of graphene oxide flakes dispersed uniformly by templating of nano cellulose.

[0038] FIG. 10 provides a view of graphene-oxide/nano-cellulose fibers from solution spun in air.

[0039] FIG. 11 provides a view of graphene-oxide/nano-cellulose fibers from solution spun in air.

[0040] FIG. 12 provides a view of graphene-oxide/nano-cellulose fibers from solution spun in air.

[0041] FIG. 13 provides a view of carbon fibers obtained from PAN-templated Graphene composite

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] The present invention may be embodied in various forms and the details of the preferred embodiments of the present invention will be described in the subsequent content with reference to the accompanying drawings. The drawings show and depict only the preferred embodiments of the invention and shall not be considered as limitations to the scope of the present invention. Modifications of the shape of the present invention shall too be considered to be within the spirit of the present invention.

[0043] FIG. 1 shows an embodiment of an operational flowchart of the method of manufacturing graphene into carbon fiber according to the present invention. As shown in FIG. 1, the method of the present invention generally comprises the steps of mixing graphene oxide S10 with other components in a solvent, or melt formed compound, forming the fibers via air-spray or electrospinning, dry spinning, or the like S20, and applying a heat treatment between 200° C. to 500° C. S30. By altering the heat treatment applied, the qualities of the resulting carbon fiber can be manipulated and enhanced. In a preferred embodiment of the present invention the heating process heats the fibers to 300° C. in air S30. In one embodiment, this heating may be performed for approximately 150 to 250 minutes, although this timing may vary depending on embodiment.

[0044] FIG. 2 shows another embodiment of an operational flowchart of the method of manufacturing graphene into carbon fiber according to the present invention. As shown in FIG. 2, the method of the present invention generally comprises the steps of mixing graphene oxide S10 with other components, forming the fibers via air-spray or electrospinning, dry spinning, or the like S20, applying a heat treatment between 200° C. to 500° C. S30, and applying a further heat treatment between 600 to 900° C. for pyrolysis to form primary carbon fibers S40. In a preferred embodiment of the present invention the heating process heats the fibers up to 300° C. in air S30 after which the fibers under inert gas condition, such as nitrogen, or argon, increase temperature to 650° C. for pyrolysis of cellulose and to create chemical bonding crosslinks of GO with cellulose-formed graphene layers S40.

[0045] Referring to FIG. 3, yet another embodiment of an operational flowchart of the method of manufacturing graphene into carbon fiber according to the present invention. As shown in FIG. 3, the method of the present invention generally comprises the steps of mixing graphene oxide S10 with other components, forming the fibers via air-spray or electrospinning, dry spinning, or the like S20, applying a heat treatment between 200° C. to 500° C. S30, applying a further heat treatment between 600 to 900° C. for pyrolysis to form primary carbon fibers S40, and applying a further heat treatment heated to 1500 to 2000 ° C. S50 which results in a further refined and crystalized carbon fiber. In a preferred embodiment of the present invention the heating process heats the fibers up to 300° C. in air S30. In varying embodiments, fibers may be formed into products (such as pipes, panels, and the like) either before further processing steps, or after. After the initial heating the fibers, under inert gas condition, such as nitrogen, or argon, may be increased in temperature to 650° C. for pyrolysis of cellulose and create chemical bonding crosslinks of GO with cellulose-formed graphene layers S40; further more in a hydrogen environment, anneal the fibers to 1200° C. for 2 hours, and then increase to 2000 ° C. for two hours to ensure the perfection of crystallization of the graphitic carbon fibers S50. In various examples, the resultant fiber materials may be formed into products or components such as airplane parts, trucks, cars, and the like. Further, such fibers may be used in concrete or cement composite constructions, and may be used instead of or in addition to polymer fibers.

[0046] FIG. 4 provides a preferred embodiment of the resulting carbon fiber created with the use of the method of manufacturing graphene into carbon fiber according to the present invention detailed in FIG. 1.

[0047] FIG. 5 provides a preferred embodiment of the resulting carbon fiber created with the use of the method of manufacturing graphene into carbon fiber according to the present invention detailed in FIG. 2.

[0048] In a preferred embodiment of the present invention the resulting carbon fibers may be used to create pipes and tubes that are resistant to corrosion and are capable of replacing common polyvinyl chloride (PVC) pipes as well as copper and lead based pipes. The resulting carbon fiber piping would have improved tensile strength, be able to endure increased temperature stress ranges, and have improved resistance to corrosion when compared to the pipes current found in use across the world. Another preferred embodiment would be the use of carbon fiber to make piping or tubing used to hold or transport drinking water.

EXAMPLE 1

[0049] A cotton candy style spinning machine is used to melt a compound (such as that discussed herein) and spin it into precursor fibers. The compound was made by mixing over 30% (wt.) graphene oxide flakes in mass with a low melt point (<250° C.) polymer, such as candy powder, PLA, PVA, and other low melt point polymers listed herein, among others, in air. A trace of amount nickel (II) oxide (<5% in wt.) was added into the compound to function as Ni catalyst source for carbon fiber formation in post-treatment process. FIG. 6 provides a view of the compound melted, while FIG. 7 provides a view of an embodiment of the melt-spun fibers.

[0050] The precursor fibers were pulled out to form bundle fibers (FIG. 8), then put into a tube furnace with process of oxidation in air, carbonization with flowing nitrogen, and then followed by additional formation of multilayer graphene on the fibers under gases flow of hydrogen and methane, then annealed to remove defects and to form graphitic crystals in nitrogen from a temperature range of room temperature to 1600° C., respectively. The product shows a tensile strength of 0.45 Mpa at first treatment of lower than 500° C., then increase to 1172 Mpa (>1.0 GPa) after annealing post treatment of 1600° C. under nitrogen for 4 hours. FIG. 8 provides a view of graphene carbon fiber in this invention prepared from graphene oxide under the inducing of polymer templating: arrows point out the multilayer graphene grown in the post-treatment of annealing in the gases flow of methane and hydrogen at higher temperature. Trace catalyst is within the carbon fibers as final product.

EXAMPLE 2

[0051] A cellulose solution was prepared by dissolving nano-cellulose powder into an aqueous solution of mixture of nickel (II) hydroxide with 1,3-diaminopropane. Then a heavy mass load of graphene oxide nanoflake powders are dispersed in the nano cellulose mixture solution to form a uniform graphene nanoflake suspension. FIG. 9 shows the SEM image of a drop of this suspension as dried film showing the graphene oxide flakes dispersed uniformly by templating of nano celluloses.

[0052] Solution precursor fibers were prepared by directly spinning the mixture in air (FIGS. 10-12: air-drying spun fibers). After similar treatment as Example 1, the final fiber obtained at lower than 600° C. is 625 Mpa, and after annealed at 1600° C., its shows a tensile strength of 1773 Mpa (>1.5 Gpa). As can be seen in FIGS. 10-11, Graphene-oxide/nano-cellulose fibers are shown formed from solution spun in air.

EXAMPLE 3

[0053] Graphene oxide flakes were dispersed in the templating solution of diluted polyacrylonitrile (PAN) in dimethylformamide (DMF). Electrospinning was used to generate nanosized fibers (FIGS. 4 and 5), or solution drawing to form larger sized graphene oxide/PAN fibers (FIG. 11). Similar post-treatment as example 1 and 2 were performed.

[0054] The electro-spun fibers show a tensile strength of 2010 Mpa (>2 Gpa) after 1600° C. annealing, for example such as that described in example 1, while the drawn fibers when aligned (FIG. 11) gives tensile strength of 2586 Mpa (>2.5 Gpa) after the same post-treatment. The resulting carbon fibers obtained from the PAN-templated graphene composites can be seen in FIG. 11, having a composition of C:O:Ni≈92:7:1.

[0055] Further treatment the as-processed fibers from 1600° C. to 2000° C. should generate high performance carbon fibers that should have properties closed to conventional PAN fibers. In this invention, we prefer using lower temperature annealing to obtain practical carbon fibers with tensile strength between carbon nanotubes and conventional PAN carbon fibers to satisfy most general applications. This invention does not exclude the applications in aerospace such as space vehicles and airplanes if the invented carbon fibers satisfy the entire properties of those criterial requests.

[0056] While several variations of the present invention have been illustrated by way of example in preferred or particular embodiments, it is apparent that further embodiments could be developed within the spirit and scope of the present invention, or the inventive concept thereof. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention, and are inclusive, but not limited to the following appended claims as set forth.