Method and composition for manufacturing graphene polyurethane foam

Abstract

A method for manufacturing a polyurethane foam is provided herein. The method comprises the step of dispersing turbostratic graphene in a polymerization solution. The polymerization solution comprises a first component for polymerization into a polymer. The method comprises the step of chemically converting the polymerization solution into a polyurethane foam by adding a second component for polymerization with the first component. Additionally, a polyurethane foam comprising turbostratic graphene and a polymer formed from the polymerization of a polyol and an isocyanate is provided herein. Additionally, a turbostratic graphene dispersion comprising turbostratic graphene and a solvent for dispersing the turbostratic graphene is provided herein.

Description

Technology Field

[0001] The embodiments disclosed herein relate to a composition and a method for manufacturing polyurethane foam, in particular graphene polyurethane foam. Background Technology

[0002] Polyurethane foam is used in a variety of applications. Adding graphene to the components for manufacturing polyurethane foam can provide various advantages. However, the graphene dispersion in the components may not be able to contain a high concentration of conventional graphene. Turbostratic graphene offers various advantages by surpassing conventional graphene due to its turbostratic properties. For example, turbostratic graphene has fewer layers of graphene compared to conventional graphene, which allows for a higher concentration of graphene in the graphene dispersion.

[0003] Furthermore, turbostratic graphene dispersions could not previously be produced at high concentrations due to the low yield of graphene produced by chemical methods. However, turbostratic graphene can be produced in large quantities by Joule heating of a carbon feedstock. The problem to be solved

[0004] Therefore, there is a need for a novel method for manufacturing polyurethane foam and a novel polyurethane foam containing turbostratic graphene. Additionally, there is a need for a turbostratic graphene dispersion that can be used in the manufacture of polyurethane foam. Furthermore, there is a need for a high-concentration turbostratic graphene dispersion that can be used as a master batch to allow for increased ease of storage of the dispersion. means of solving the problem

[0005] According to some embodiments, there is a method for manufacturing a polyurethane foam. The method comprises the step of dispersing turbostratic graphene in a polymerization solution. The polymerization solution comprises a first component for polymerization into a polymer. The method also comprises the step of chemically converting the polymerization solution into a polyurethane foam by adding a second component for polymerization with the first component.

[0006] The above method may provide that the first component is a monomer or a polymer.

[0007] The above method may provide that the second component is a monomer or a polymer.

[0008] The above method may provide for turbostratic graphene to be dispersed in a polymerization solution by at least one of the group comprising ultrasonic treatment, shear mixing, stirring, shaking, vortex shaking, milling, ball milling, and grinding.

[0009] The above method can provide that the first component is a polyol and the second component is an isocyanate.

[0010] The above method may provide that the polyol is at least one of the group comprising petroleum-based polyols and bio-based polyols.

[0011] The above method may provide that the petroleum-based polyol is manufactured from at least one of the group comprising mineral oil, paraffinic oil, naphthenic oil, crude oil, kerosene, aliphatic oil, aromatic oil, coal oil, diesel oil, motor oil, and turbine oil.

[0012] The above method may provide that the bio-based polyol is prepared from at least one of the group comprising vegetable oil, seed oil, soybean oil, rapeseed oil, canola oil, peanut oil, cottonseed oil, sunflower oil, olive oil, grapeseed oil, linseed oil, castor oil, fish oil, algae oil, and mustard seed oil.

[0013] The above method may provide that the isocyanate is at least one of the group comprising methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H12MDI), 1,5-naphthalene diisocyanate (NDI), tetramethylxylene diisocyanate (TMXDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CDI), and tolidine diisocyanate (TODI).

[0014] The above method may also include the step of dispersing turbostratic graphene into a solvent before dispersing it into a polymerization solution.

[0015] The above method may also include the step of heating the solvent while dispersing turbostratic graphene into the solvent.

[0016] The above method may provide that the solvent comprises at least one of the group comprising an aqueous solvent, an alcohol-based solvent, an organic solvent, and an oil-based solvent.

[0017] The above method can provide that the aqueous solvent is a water-surfactant solution.

[0018] The above method comprises an aqueous solvent comprising sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), lithium dodecyl sulfate (LDS), sodium deoxycholate (DOC), sodium taurodeoxycholate (TDOC), cetyltrimethylammonium bromide (CTAB), tetradecyltrimethylammonium bromide (TTAB), pluronic F87, polyvinylpyrrolidone (PVP), polyoxyethylene (40), nonylphenyl ether (CO-890), Triton X-100, Tween 20, Tween 80, polycarboylate (H14N), sodium chlorate, tetracyanoquinodimethane (TCNQ), pyridinium tribromide, N,N'-dimethyl-2,9-diazaferropyrenium divalent cation, N,N'-dimethyl-2,7-diazapyrene, tetrasodium 1,3,6,8-Pyrenetetrasulfonate, 1-Pyrenemethylamine hydrochloride, 1,3,6,8-Pyrenetetrasulfonic acid tetrasodium salt hydrate, 1-Pyrenecarboxylic acid, 1-Aminopyrene, 1-Aminomethylpyrene, 1-Pyrenecarboxylic acid, 1-Pyrenebutyric acid, 1-Pyrenebutanol, 1-Pyrenesulfonic acid hydrate, 1-Pyrenesulfonic acid sodium salt, 1,3,6,8-Pyrenetetrasulfone tetraacid tetrasodium salt, 6,8-Dihydroxy-1,3-Pyrenedisulfonic acid disodium salt, 8-Hydroxypyrene-1,3,6-trisulfonic acid trisodium salt, Perylenebisimide bolaamphiphile, Tetrabutylammonium hydroxide (TBA), It may provide at least one of the group including 9-anthracene carboxylic acid.

[0019] The above method may provide that the aqueous solvent is at least one of the group comprising a water-surfactant solution, a water-pluronic solution, and a water-dihydrolevoglucosenone solution.

[0020] The above method may provide that the alcohol-based solvent is at least one of the group comprising methanol, ethyl alcohol, isopropyl alcohol, butanol, pentanol, ethylene glycol, propylene glycol, and glycerol.

[0021] The above method may provide that the organic solvent is at least one of the group comprising toluene, N-methyl-2-pyrrolidone (NMP), xylene, benzene, 1,2-dichlorobenzene (DCB), and dimethylformamide (DMF).

[0022] The above method may provide that the organic solvent is at least one of the group comprising seed oil, soybean oil, rapeseed oil, canola oil, peanut oil, cottonseed oil, sunflower oil, olive oil, grapeseed oil, linseed oil, castor oil, fish oil, algae oil, and mustard seed oil.

[0023] The above method can provide a concentration of turbostratic graphene dispersed in a solvent of 1 to 15 mg / mL.

[0024] The above method can provide turbostratic graphene having misoriented graphene layers relative to each other.

[0025] The above method involves turbostratic graphene of 200 to 300 m 2 It can provide a surface area of ​​ / g.

[0026] The above method can provide turbostratic graphene having 1 to 5 layers of graphene.

[0027] The above method can provide turbostratic graphene having a particle diameter of 5 nm to 2000 nm.

[0028] The above method can provide turbostratic graphene having an oxygen content of 0.1% to 5% based on atomic ratio.

[0029] The above method may also include the step of heating the polymerization solution while dispersing turbostratic graphene.

[0030] Turbostratic graphene polyurethane foam can be manufactured by the above method.

[0031] According to some embodiments, there is a polyurethane foam containing turbostratic graphene. The polyurethane foam also comprises a polymer formed from the polymerization of a polyol and an isocyanate.

[0032] Polyurethane foam can provide an increase in the compressive strength of the polyurethane foam with turbostratic graphene compared to polyurethane foam without turbostratic graphene.

[0033] Polyurethane foam can provide turbostratic graphene to reduce the average pore size of the polyurethane foam compared to polyurethane foam without turbostratic graphene.

[0034] Polyurethane foam can provide increased thermal insulation of polyurethane foam with turbostratic graphene compared to polyurethane foam without turbostratic graphene.

[0035] Polyurethane foam can be provided with turbostratic graphene increasing the insulation of the polyurethane foam by at least 60%.

[0036] Polyurethane foam can provide increased sound absorption of the polyurethane foam with turbostratic graphene compared to polyurethane foam without turbostratic graphene.

[0037] Polyurethane foam is 20 to 95 kg / m² 3 It can provide having a density of

[0038] Polyurethane foam can provide a layer of graphene in which turbostratic graphene has misaligned orientations relative to each other.

[0039] Polyurethane foam contains turbostratic graphene of 200 to 300 m2 It can provide a surface area of ​​ / g.

[0040] Polyurethane foam can provide turbostratic graphene having 1 to 5 layers of graphene.

[0041] Polyurethane foam can provide turbostratic graphene having a particle diameter of 5 nm to 2000 nm.

[0042] Polyurethane foam can provide turbostratic graphene having an oxygen content of 0.1% to 5% on an atomic ratio basis.

[0043] Polyurethane foam may be provided such that turbostratic graphene is prepared from at least one of the group comprising petroleum coke, tire carbon black, carbon black, metallurgical coke, plastic ash, plastic powder, ground coffee, anthracite coal, coal, corn starch, pine bark, polyethylene microwax, wax, Chemplex 690, cellulose, naphthenic oil, asphaltene, gilsonite, and carbon nanotubes.

[0044] Polyurethane foam can provide for the production of turbostratic graphene by heating carbon powder.

[0045] Polyurethane foam can enable the production of turbostratic graphene by heating a carbon-based pill.

[0046] Polyurethane foam can provide for the production of turbostratic graphene from a carbon feedstock by heating the carbon feedstock to a temperature of 2800°C to 3000°C.

[0047] The polyurethane foam may be provided such that the polyol is at least one of the group comprising petroleum-based polyols and bio-based polyols.

[0048] The polyurethane foam may be provided such that the isocyanate is at least one of the group comprising methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H12MDI), 1,5-naphthalene diisocyanate (NDI), tetramethylxylene diisocyanate (TMXDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CDI), and tolidine diisocyanate (TODI).

[0049] Polyurethane foam can be used for car seats, bedding, furniture, flooring, road fill, or building construction.

[0050] Polyurethane foam can be used as a urethane coating, adhesive, sealant, epoxy, or elastomer.

[0051] According to some embodiments, there is a kit for manufacturing a polyurethane foam comprising turbostratic graphene. The kit also comprises a polymerization solution for conversion into a polyurethane foam. The polymerization solution comprises a first component for polymerization into a polymer.

[0052] The kit may also include a second component for polymerizing with the first component.

[0053] The kit may provide that the first component is a monomer or a polymer.

[0054] The kit may provide that the second component is a monomer or a polymer.

[0055] The kit may provide a first component that is a polyol and a second component that is an isocyanate.

[0056] The kit may provide that the polyol is at least one of the group including petroleum-based polyols and bio-based polyols.

[0057] Turbostratic graphene polyurethane foam can be manufactured using the kit.

[0058] According to some embodiments, there is a turbostratic graphene dispersion containing turbostratic graphene. The turbostratic graphene dispersion also includes a solvent for dispersing turbostratic graphene.

[0059] The turbostratic graphene dispersion can provide a turbostratic graphene concentration of 1 mg / mL to 15 mg / mL in the solvent.

[0060] A turbostratic graphene dispersion can provide a turbostratic graphene having graphene layers that are misaligned in orientation with respect to one another.

[0061] The turbostratic graphene dispersion can provide that the turbostratic graphene is graphene having five or fewer layers.

[0062] The turbostratic graphene dispersion can be provided such that the solvent for dispersing the turbostratic graphene is a polyol solution for conversion into polyurethane foam.

[0063] The turbostratic graphene dispersion may be provided such that the solvent for dispersing the turbostratic graphene is an isocyanate solution for conversion into polyurethane foam.

[0064] The turbostratic graphene dispersion may be provided such that the solvent for dispersing the turbostratic graphene is at least one of the group comprising an aqueous solvent, an alcohol-based solvent, an organic solvent, and an oil-based solvent.

[0065] The turbostratic graphene dispersion can be provided with an aqueous solvent that is a water-surfactant solution.

[0066] The turbostratic graphene dispersion can provide a concentration of turbostratic graphene in an aqueous solvent of 1 to 5 mg / mL.

[0067] The turbostratic graphene dispersion may be provided such that the aqueous solvent is at least one of the group comprising a water-surfactant solution, a water-pluronic solution, and a water-dihydrolevoglucosenone solution.

[0068] The turbostratic graphene dispersion is an aqueous solvent comprising sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), lithium dodecyl sulfate (LDS), sodium deoxycholate (DOC), sodium taurodeoxycholate (TDOC), cetyltrimethylammonium bromide (CTAB), tetradecyltrimethylammonium bromide (TTAB), pluronic F87, polyvinylpyrrolidone (PVP), polyoxyethylene (40) nonylphenyl ether (CO-890), Triton X-100, Tween 20, Tween 80, polycarboylate (H14N), sodium chlorate, tetracyanoquinodimethane (TCNQ), pyridinium tribromide, N,N'-dimethyl-2,9-diazaferropyrenium divalent cation, N,N'-dimethyl-2,7-diazapyrene, Tetrasodium 1,3,6,8-pyrenetetrasulfonate, 1-pyrenemethylamine hydrochloride, 1,3,6,8-pyrenetetrasulfonic acid tetrasodium salt hydrate, 1-pyrenecarboxylic acid, 1-aminopyrene, 1-aminomethylpyrene, 1-pyrenecarboxylic acid, 1-pyrenebutyric acid, 1-pyrenebutanol, 1-pyrenesulfonic acid hydrate, 1-pyrenesulfonic acid sodium salt, 1,3,6,8-pyrenetetrasulfone tetrasodium salt, 6,8-dihydroxy-1,3-pyrenedisulfonic acid disodium salt, 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt, perylenebisimide bolar-type amphiphilic medium, tetrabutylammonium hydroxide (TBA), 9-anthracene It is possible to provide at least one of the group including carboxylic acids.

[0069] The turbostratic graphene dispersion may be provided with an alcohol-based solvent that is at least one of the group comprising methanol, ethyl alcohol, isopropyl alcohol, butanol, pentanol, ethylene glycol, propylene glycol, and glycerol.

[0070] The turbostratic graphene dispersion can provide a concentration of turbostratic graphene in an alcohol-based solvent of 1 to 50 mg / mL.

[0071] The turbostratic graphene dispersion can provide a concentration of turbostratic graphene in an alcohol-based solvent of 6.3% w / w or less.

[0072] The turbostratic graphene dispersion may be provided with an organic solvent that is at least one of the group comprising acetone, toluene, N-methyl-2-pyrrolidone (NMP), xylene, benzene, 1,2-dichlorobenzene (DCB), dimethylformamide (DMF), and methyl ethyl ketone (MEK).

[0073] The turbostratic graphene dispersion can provide a concentration of turbostratic graphene in an organic solvent of 1 to 100 mg / mL.

[0074] The turbostratic graphene dispersion can provide a concentration of turbostratic graphene in an organic solvent of 11% w / w or less.

[0075] The turbostratic graphene dispersion may be provided with an oil-based solvent that is at least one of the group comprising vegetable oil, seed oil, soybean oil, rapeseed oil, canola oil, peanut oil, cottonseed oil, sunflower oil, olive oil, grapeseed oil, linseed oil, castor oil, fish oil, algae oil, mustard oil, mineral oil, and naphthenic oil.

[0076] The turbostratic graphene dispersion can provide a concentration of turbostratic graphene in an oil-based solvent of 1 to 100 mg / mL.

[0077] The turbostratic graphene dispersion can provide a concentration of turbostratic graphene in an oil-based solvent of 11% w / w or less.

[0078] The turbostratic graphene dispersion can be provided as a masterbatch that is 5 to 10 times more concentrated than the concentration required to manufacture polyurethane foam.

[0079] Turbostratic graphene dispersions can be provided with a polyol solvent.

[0080] The turbostratic graphene dispersion can provide heating of the polyol while dispersing the graphene.

[0081] The turbostratic graphene dispersion can provide a polyol that is stirred while dispersing graphene.

[0082] Turbostratic graphene dispersions can be provided with an isocyanate solvent.

[0083] According to some embodiments, there is a polyurethane foam containing graphene. The polyurethane foam also comprises a polymer formed from the polymerization of a polyol and an isocyanate, wherein the polyol is prepared from oil.

[0084] The polyurethane foam may provide graphene that is at least one of the group comprising turbostratic graphene, very few layer graphene, few layer graphene, multilayer graphene, and graphene nanoplatelets.

[0085] Polyurethane foam can provide a layer of graphene in which turbostratic graphene has misaligned orientations relative to each other.

[0086] Polyurethane foam contains turbostratic graphene of 200 to 300 m 2 It can provide a surface area of ​​ / g.

[0087] Polyurethane foam can provide turbostratic graphene having 1 to 5 layers of graphene.

[0088] Polyurethane foam can provide turbostratic graphene having a particle diameter of 5 nm to 2000 nm.

[0089] The polyurethane foam may be provided such that the polyol is manufactured from at least one of the group comprising petroleum-based oils and bio-based oils.

[0090] The polyurethane foam may be provided with a petroleum-based oil that is at least one of the group comprising mineral oil, paraffinic oil, naphthenic oil, crude oil, kerosene, aliphatic oil, aromatic oil, coal oil, diesel oil, motor oil, and turbine oil.

[0091] The polyurethane foam may be provided with a bio-based oil that is at least one of the group comprising vegetable oil, seed oil, soybean oil, rapeseed oil, canola oil, peanut oil, cottonseed oil, sunflower oil, olive oil, grapeseed oil, linseed oil, castor oil, fish oil, algae oil, and mustard oil.

[0092] The polyurethane foam may be provided such that the isocyanate is at least one of the group comprising methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H12MDI), 1,5-naphthalene diisocyanate (NDI), tetramethylxylene diisocyanate (TMXDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CDI), and tolidine diisocyanate (TODI).

[0093] According to some embodiments, there is a method for manufacturing a polyurethane foam. The method comprises the step of dispersing graphene in oil. The method also comprises the step of chemically converting the oil into a polyol. The method also comprises the step of chemically converting the polyol into a polyurethane foam by adding an isocyanate.

[0094] The above method may provide that the graphene is at least one of the group comprising turbostratic graphene, microlayer graphene, microlayer graphene, multilayer graphene, and graphene nanoplatelets.

[0095] The above method can provide turbostratic graphene having graphene layers that are misaligned in orientation with respect to each other.

[0096] The above method involves turbostratic graphene of 200 to 300 m 2 It can provide a surface area of ​​ / g.

[0097] The above method can provide turbostratic graphene having 1 to 5 layers of graphene.

[0098] The above method can provide turbostratic graphene having a particle diameter of 5 nm to 2000 nm.

[0099] The above method may provide that the polyol is manufactured from at least one of the group comprising petroleum-based oil and bio-based oil.

[0100] The above method may provide that the petroleum-based oil is at least one of the group comprising mineral oil, paraffinic oil, naphthenic oil, crude oil, kerosene, aliphatic oil, aromatic oil, coal oil, diesel oil, motor oil, and turbine oil.

[0101] The above method may provide that the bio-based oil is at least one of the group comprising vegetable oil, seed oil, soybean oil, rapeseed oil, canola oil, peanut oil, cottonseed oil, sunflower oil, olive oil, grapeseed oil, linseed oil, castor oil, fish oil, algae oil, and mustard seed oil.

[0102] The above method may provide that the isocyanate is at least one of the group comprising methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H12MDI), 1,5-naphthalene diisocyanate (NDI), tetramethylxylene diisocyanate (TMXDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CDI), and tolidine diisocyanate (TODI).

[0103] Upon reviewing the following description of some exemplary embodiments, other aspects and features will become apparent to those skilled in the art. Brief explanation of the drawing

[0104] The drawings included herein are intended to illustrate various examples of articles, methods, and apparatus of this specification. In the drawings: Figure 1a is a transmission electron microscope (TEM) image of turbostratic graphene according to one embodiment. FIG. 1b is a high-resolution TEM image of turbostratic graphene. The high-resolution image demonstrates a region (105) in which three to four or more layers of graphene are detected superimposed on a flat sheet according to one embodiment. FIG. 1c is a high-resolution transmission electron microscope (HRTEM) of turbostratic graphene according to one embodiment. FIG. 1d is a representative selected region electron diffraction (SAED) of the structure presented in FIG. 1c, showing the turbostratic properties of graphene according to one embodiment. FIG. 1e is an intensity profile of SAED in FIG. 1d according to one embodiment. FIG. 1f is an X-ray photoelectron spectroscopy (XPS) spectrum of a representative sample of turbostratic graphene prepared by Joule heating according to one embodiment. Figure 2a is a flowchart demonstrating a method for manufacturing polyurethane foam (PUF). FIG. 2b shows a comparison of the physical properties of a turbostratic graphene-based PUF composite (TGPU) with respect to a conventional graphene-containing PUF composite (XGPU), with the relative change to a PUF without any additives (standard PU). FIG. 3 is an image of foam pore size as a function of additive material according to one embodiment. FIG. 4 is an image of a batch H of polyurethane foam before and after compression with a 100g load according to one embodiment. A PUF without any additives is shown before (405) and after compression. Figure 5 is a graph showing the thermal conductivity of four types of polyurethane foam according to one embodiment. FIG. 6 is an image of a device for measuring the sound absorption characteristics of four types of polyurethane foam according to one embodiment. FIG. 7 is a turbostratic graphene-oil dispersion before and after 3 weeks of storage, according to one embodiment. Figure 8 is a flowchart demonstrating a method for manufacturing polyurethane foam. Specific details for implementing the invention

[0105] Various devices or processes will be described below to provide examples of each claimed embodiment. The embodiments described below do not limit any claimed embodiment, and any claimed embodiment may include a process or device different from that described below. The claimed embodiments are not limited to all of the features of any single device or process described below, or to a device or process having features common to multiple or all of the devices described below.

[0106] The term "graphene" refers to sp² densely packed in a honeycomb crystal lattice. 2- Refers to a material that is a planar sheet of bonded carbon atoms one atom thick, containing an intact ring structure of carbon atoms and aromatic bonds throughout at least the majority of the internal sheet, and lacking significant oxidative modification of the carbon atoms. Graphene is distinguished from graphene oxide in that it has a lower degree of oxygen-containing groups, such as OH, COOH, and epoxides. The term "graphene monolayer" refers to graphene that is a single layer of graphene. The term "microlayer graphene" refers to graphene that is 1 to 3 layers of graphene. The term "microlayer graphene" refers to graphene that is 2 to 5 layers of graphene. The term "multilayer graphene" refers to graphene that is 2 to 10 layers of graphene.

[0107] The term "turbostratic graphene" refers to graphene with little order between the layers. Other terms that may be used include orientation mismatch, twist, rotation, rotational defects, and weak bonding. The rotational stacking of turbostratic graphene helps to relax interlayer bonding and increase interplanar spacing, yielding superior physical properties compared to competitive graphene structures when compared on a similar weight basis. Subtle differences in adjacent layer stacking orientations indicate, in themselves, significant differences in product performance attributes. A clear and significant performance advantage in the case of turbostratic graphene is that multilayer graphene structures are more easily separated into a few individual graphene layers, and the graphene layers tend not to recombine. The turbostratic properties of graphene can be observed and confirmed by Raman spectroscopy, transmission electron microscopy (TEM), selected area electron diffraction (SAED), scanning transmission electron microscopy (STEM), and X-ray diffraction (XRD) analysis.

[0108] One method for manufacturing bulk turbostratic graphene is by Joule heating carbon powder or carbon-based peels. Turbostratic graphene can be produced from carbon peels by Joule heating at temperatures of 2800 to 3000°C. The synthesis of graphene from carbon peels primarily produces few-layer turbostratic graphene. Turbostratic graphene consists of graphene layers that are misaligned relative to one another. Therefore, the graphene layers are not AB stacked and are misaligned relative to one another. The graphene layer configuration of turbostratic graphene allows for easier dispersion of graphene powder in a liquid. Easier dispersion of graphene enables the production of superior graphene composites.

[0109] A Joule heating synthesis method and a composition thereof are described in a Patent Cooperation Treaty application with international publication number WO 2020 / 051000 A1 (Tour et al.) with an international publication date of March 12, 2020 (the full text of which is incorporated herein by reference).

[0110] The graphene layers of turbostratic graphene are randomly stacked instead of the AB stacked graphene found in other types of bulk graphene. The turbostratic properties of the disclosed graphene make it easier to disperse at higher concentrations and maintain the dispersed state for long periods, such as days to years. Turbostratic graphene can be dispersed at concentrations ranging from 1 mg / mL (1 g / L) to 15 mg / mL (15 g / L) depending on the medium. In contrast, conventional graphene can be dispersed only up to 1 mg / mL (1 g / L). Turbostratic graphene dispersions can be used in the manufacture of turbostratic graphene polyurethane foam (TGPUF). For example, a turbostratic graphene distribution in water, oil, or polyol can be used to manufacture TGPUF. In some embodiments, turbostratic graphene is dispersed directly in the medium, and in some embodiments, a second additive medium is used to aid in the dispersion of turbostratic graphene.

[0111] Turbostratic graphene is 120 to 150 m 2 Compared to conventional graphene at 100 to 300 m / g 2 It can have a surface area of ​​ / g.

[0112] Turbostratic graphene can have particle or grain sizes ranging from 5 nm to several microns compared to conventional graphene having a particle diameter of 4 to 6 microns.

[0113] Referring to FIG. 1a, a transmission electron microscope (TEM) image of turbostratic graphene according to one embodiment is illustrated. To demonstrate the scale of the image, a 200 nm scale bar is shown at the bottom left of the image. Referring to FIG. 1b, a high-resolution TEM image of turbostratic graphene is illustrated. The high-resolution image demonstrates a region (105) in which three to four or more layers of graphene are detected superimposed on a flat sheet according to one embodiment.

[0114] Turbostratic graphene has 1 to 5 non-AB stacked graphene layers, as exemplified in FIGS. 1a and 1b. In contrast, conventional graphene has more than 5 AB stacked graphene layers, typically more than 10 AB stacked graphene layers. The energy required to exfoliate AB stacked graphite or graphene into few-layer graphene is much higher than in the case of turbostratic graphene. For example, AB stacked graphite or graphene can be exfoliated using high-energy sonication and harsh chemical methods. Due to the larger number of AB stacked graphene layers, conventional graphene is more difficult to disperse at higher concentrations, and their composites have a higher weight per unit volume because many of the graphene sandwiched between the outer layers does not participate in composite enhancement.

[0115] Referring to FIG. 1c, a high-resolution transmission electron microscope (HRTEM) of turbostratic graphene prepared from a sheet according to one embodiment is illustrated. The inset image (115) shows a high-magnification image of the sheet edge showing three graphene planes.

[0116] A method for synthesizing graphene by heating a carbon peel and a composition thereof are described in the Patent Cooperation Treaty application with international application number PCT / CA2020 / 051368 (Mancevski) with the international filing date of October 13, 2020 (the full text of which is incorporated herein by reference).

[0117] Referring to FIG. 1d, a representative selected region electron diffraction (SAED) of the structure presented in FIG. 1c, which indicates the turbostratic properties of graphene according to one embodiment, is illustrated. The arc (110) is observed as a ring with distinct bright spots superimposed. The points marked with circles within the arc (110) in the 60-degree arc (120) represent individual sub-stacks or sheets having different angular orientations (up to 53°) with respect to a reference (0° point) placed to the right of the arc. The dashed box on the SAED pattern is enlarged on the upper right of FIG. 1d and indicates the contribution of each individual point (125).

[0118] Referring to FIG. 1e, an intensity profile of the SAED in FIG. 1d according to one embodiment is illustrated. The distance of plane (130) is shown as 0.35 nm, plane (100) is shown as 0.21 nm, and plane (110) is shown as 0.12 nm. The distances are corrected for an aluminum metal SAED reference.

[0119] The high purity of graphene and the low oxygen content of turbostratic graphene imply that composites prepared using turbostratic graphene can have fewer defects and impurities, and thus a lower proportion of them in the composite, enabling stronger interfacial interactions between the graphene and the polymer matrix. Additionally, the low oxygen content of graphene can provide improved interactions with nonpolar (hydrophobic) polymer matrices.

[0120] High-resolution transmission electron microscope (HRTEM) images of a representative sheet of Joule-heated graphene in FIG. 1c demonstrate the turbostratic properties of graphene. The sheet structure in the center of the image has dimensions of approximately 500 x 700 nm and consists of a few stacked layers of graphene. The inset shows a high-magnification image of the sheet edge showing three graphene planes. Wrinkles (140) and ripples (145) are observed on the edge of the central structure, which is a characteristic of the two-dimensional material.

[0121] SAED in FIG. 1d indicates the turbostratic properties of the central sheet, where it is possible to observe multiple distinct bright spots within a 60° arc (120). The arc (120) is visually depicted using a curved arrow between two white lines defining the start and end of the arc. Each bright spot is caused by electron diffraction of a single graphene layer or a few graphene layers having the same orientation. The angular orientation of the selected bright spot is calculated for any one selected point as 0° (located to the right of the 60° arc (120)), demonstrating the turbostratic properties of the graphene sheet in image FIG. 1c (Gupta et al., Twist-Dependent Raman and Electron Diffraction Correlations in Twisted Multilayer Graphene , J. Phys. Chem. Lett., 2020, 11, 8, 2797-2803).

[0122] Referring to FIG. 1f, an X-ray photoelectron spectroscopy (XPS) spectrum of a turbostratic graphene sample from FIG. 1c prepared by Joule heating of a peel according to one embodiment is illustrated. The upper graph (150) shows a survey scan, and the lower graph (155) shows a carbon-edge high-resolution scan and properties.

[0123] XPS indicates the high purity and low oxygen content of turbostratic graphene. The scan (150) shows a turbostratic graphene sample composed of more than 98% carbon (atomic ratio). Other detected elements include oxygen and sulfur, but in small amounts (1.2% and 0.4%, respectively). The low oxygen content is characteristic of the Joule heating process and is significantly lower compared to the chemical method of producing graphene by graphite exfoliation (>10%, atomic ratio, also measured by XPS) (Al-Gaashaniab et al., XPS and structural studies of high quality graphene oxide and reduced graphene oxide prepared by different chemical oxidation methods , Ceramics International, 2019, 45, 11, 14439-1444). High-resolution spectra on the carbon edge (155) are from the literature (Lesiak et al., C sp 2 / sp 3 Hybridisations in carbon nanomaterials - XPS and (X)AES study It shows a deconvoluted carbon peak from the four main peaks confirmed by a similar analysis of carbon materials in , Applied Surface Science, 2018, 452, 223-231). The most prominent peak is located at 284.45 eV (~80% carbon atoms), and sp 2 It is attributed to carbon atoms with hybridization (C=C). The other peak is sp 3 It represents carbons having hybridization and the presence of CO bonds (C-OH and C=O). sp 2 The high hybridization content (nearly 80%) indicates that most carbon atoms in the sample are arranged in a 2D structure.

[0124] The high purity and low oxygen content of the graphene of the present disclosure provide that composites prepared using turbostratic graphene have fewer defects and impurities, and thus require a smaller percentage of the composite to have superior performance compared to conventional composites.

[0125] Conventional production of turbostratic graphene grown via chemical vapor deposition (CVD) and other atomic deposition methods is slow and may not be able to produce more than a few layers of graphene on a substrate; therefore, the high yield required for the production of turbostratic graphene composites was impossible with previous methods. The advantage of turbostratic graphene produced by Joule heating is that the graphene is produced in large quantities, such as grams to kilograms, in powder form. The high yield allows turbostratic graphene produced by Joule heating to be used in composites.

[0126] Turbostratic graphene can be used as an additive for preparing polyurethane foam composites by adding 0.01 wt% to 5 wt% of turbostratic graphene to polyurethane foam components, such as polyols or isocyanates, before mixing the polyurethane foam components. The embodiments of the present invention demonstrate the use of 0.063 wt% of turbostratic graphene in the foam material, but any concentration of turbostratic graphene from 0.01 wt% to 5 wt% may be used.

[0127] A turbostratic graphene polyurethane foam is provided that offers various advantages over polyurethane foams having graphite nanoplatelet (GNP) materials, AB stacked graphene, and carbon nanoparticles.

[0128] In one embodiment, turbostratic graphene is 120 m 2 / g to 150m 2 200m compared to conventional graphene / g 2 / g to 300m 2 It can have a larger surface area of ​​ / g.

[0129] In one embodiment, turbostratic graphene may have a particle diameter of 5 nm to 200 nm when produced from a carbon black feedstock, or 100 nm to 2000 nm when supplied from petroleum coke or coffee grounds. In comparison, conventional turbostratic graphene has a particle diameter of 4 to 6 microns.

[0130] In one embodiment, the dispersion of turbostratic graphene may have a concentration of 1 mg / mL (1 g / L) to 15 mg / mL (15 g / L). In comparison, a conventional graphene dispersion may have a concentration of only up to 1 mg / mL (1 g / L).

[0131] In one embodiment, turbostratic graphene may have a low oxygen content of 0.1% to 5% on an atomic basis. In comparison, conventional graphene typically has a higher oxygen content of 10% or more on an atomic basis. If desired, the oxygen content of turbostratic graphene may be increased by intentionally introducing oxygen content after the turbostratic graphene is produced.

[0132] In one embodiment, the concentration of turbostratic graphene in the turbostratic graphene polyurethane foam may be from 0.01 wt% to 5 wt%. The improved dispersion properties of turbostratic graphene and a smaller number of graphene layers allow for an increased concentration of graphene in the polyurethane foam, and thus the turbostratic graphene polyurethane foam has a lower weight per unit volume compared to polyurethane foam with traditional graphene.

[0133] Example 1 - Preparation of Polyurethane Foam

[0134] Polyurethane foam (PUF) containing manufactured and tested turbostratic graphene is provided herein. One method of manufacturing turbostratic graphene is through resistive (ohm) Joule heating, and is subsequently referred to as Joule-heated graphene. The results are compared with PUF manufactured without additives, PUF manufactured using carbon black (CB) additives, and PUF manufactured using conventional graphene. The turbostratic graphene-based PUF had superior mechanical properties compared to PUF without additives or PUF containing other types of graphene.

[0135] Referring to FIG. 2a, a flowchart illustrating a method (200) for manufacturing a polyurethane foam according to one embodiment is illustrated. The method (200) includes the step of dispersing turbostratic graphene in a polymerization solution at (210). Optionally, the method (200) includes the step of heating the polymerization solution while dispersing turbostratic graphene at (211). The polymerization solution includes a first component for polymerization into a polymer. The method (200) also includes the step of chemically converting the polymerization solution into a polyurethane foam by adding a second component for polymerization with the first component at (215). Optionally, the method (200) includes the step of dispersing turbostratic graphene into a solvent at (205) before dispersing turbostratic graphene in the polymerization solution at (210). Optionally, the method (200) includes the step of heating the solvent while dispersing turbostratic graphene in (206).

[0136] In some embodiments, the first component is a polyol and the second component is an isocyanate. In some embodiments, the first component is an isocyanate and the second component is a polyol. The polymerization solution is a solution that can be converted into a polyurethane foam. In some embodiments, the first component is a monomer or a polymer. In some embodiments, the second component is a monomer or a polymer.

[0137] Referring to FIG. 2b, a comparison of the physical properties of a turbostratic graphene-based PUF composite (TGPU) with respect to a conventional graphene-based PUF composite (XGPU) is illustrated. An increase in physical properties is shown for a PUF without any additives (standard PU).

[0138] In one embodiment, a commercial Flex Foam-iT! polyurethane foam kit can be used to manufacture PUF. The kit contains two parts. Part A is a methylene diphenyl diisocyanate (MDI)-based isocyanate material, and Part B is a polyol material. Typically, the material in Part B is a petroleum-based polyol, but it may also be a bio-based polyol, or a combination of petroleum-based and bio-based polyols.

[0139] One example of the preparation of turbostratic graphene PUF (PUF / TG) is described as Batch H. Turbostratic graphene is prepared from a carbon feedstock consisting of 30% bark + 70% petroleum coke, manufactured in the form of a compressed carbon-based peel, and Joule heated to convert carbon into turbostratic graphene. First, 20 g of partial B polyol (0.1%) is heated at 80 to 100°C until the polyol solution becomes less viscous, then 20 mg of turbostratic graphene is added, and the mixture is then mixed with 20 g of partial B polyol (0.1%) by sonicating the mixture until the mixture becomes uniformly black. In the next step, 11.5 g of partial A is mixed with a dispersion of partial B containing turbostratic graphene for 15 to 30 seconds, poured into a mold, and cured at room temperature for 2 hours. The amount of turbostratic graphene in the manufactured PUF / TG is 0.063 wt%. PUF using conventional graphene (PUF / XG) and PUF using carbon black (PUF / CB) were also manufactured using the same method in which turbostratic graphene was replaced with conventional graphene and carbon black, respectively.

[0140] Another example of PUF manufacturing is described as Batch R. Turbostratic graphene is prepared from a carbon feedstock consisting of 30% bark + 70% petroleum coke, manufactured in the form of a compressed carbon-based powder, and Joule heated to convert the carbon into turbostratic graphene. First, 20 mg of turbostratic graphene is dispersed with 20 ml of benzene and sonicated until the turbostratic graphene is well dispersed. Subsequently, the graphene / benzene slurry is dispersed with 11.5 g of Part A (MDI) and mixed using a magnetic stirring rod until the mixture becomes uniformly black. In the next step, 20 g of Part B (polyol) is mixed with the dispersion of Part A containing graphene / benzene for 15 to 20 seconds, then poured into a Pyrex mold and cured at room temperature for 2 hours. The amount of turbostratic graphene in the PUF is 0.063%. PU / XG and PU / CB foams were manufactured using the same method in which turbostratic graphene was replaced with conventional graphene and carbon black, respectively.

[0141] Turbostratic graphene can also be dispersed in toluene, N-methyl-2-pyrrolidone (NMP), or xylene instead of benzene. Other liquid dispersants compatible with part A material (isocyanate-containing compounds, e.g., MDI) and part B material (polyol) may also be used.

[0142] The physical properties of the foam produced in Example Batch H are shown in Table 1 below.

[0143] Physical properties of TG / PUF with 0.063% turbostratic graphene content compared to additive-free PUF, CB / PUF, and XG / PUF Ultrasonically treated additive carbon in MDI Additive-free PUF 0.063% CB / PUF 0.063% XG / PUF 0.063% TG / PUF Density (kg / m³) 3 ) 72.2 61.3 74.1 76.0 Average pore size (μm) 878 716 470 402

[0144] For reference, the density of the foam for automotive applications is 42 kg / m³ 3 That is all, and the density of automobile seat cushions and backs is 20 to 95 kg / m³ 3 It must be a range.

[0145] As graphene-like materials are added, the number of foam cells increases and the foam cell size decreases. The foam cell size of a PUF with 50% petroleum and 50% bio-based polyol is in the range of 200 to 600 microns, whereas the foam cell size with 1% graphite nanopane (GNP) additive is 200 microns or less.

[0146] Referring to FIG. 3, an image of foam pore size as a function of additive material according to one embodiment is illustrated. Pore sizes of a PUF (305) without any additives, a PUF (310) having 0.063% carbon black, a PUF (315) having 0.063% conventional graphene, and a PUF (320) having 0.063% turbostratic graphene are illustrated. The circumference of a representative bubble (325) from the PUF (305) without any additives is 2.761 mm, and the area is 0.606 mm. 2 and the radius is 0.439 mm. The circumference of a typical bubble (330) from a PUF (310) having 0.063% carbon black is 2.251 mm, and the area is 0.403 mm. 2 and the radius is 0.358 mm. The circumference of a typical bubble (335) from a PUF (315) having 0.063% conventional graphene is 1.477 mm and the area is 0.174 mm 2 and the radius is 0.235 mm. The circumference of the first representative bubble (340) from the PUF (320) having 0.063% turbostratic graphene is 1.263 mm and the area is 0.127 mm 2 and the radius is 0.201 mm. The circumference of the second representative bubble (345) from the PUF (320) having 0.063% turbostratic graphene is 0.848 mm and the area is 0.057 mm 2 and the radius is 0.135 mm.

[0147] Referring to FIG. 4, images of a batch R of polyurethane foam before and after compression under a 2 kg load according to one embodiment are illustrated. A PUF without any additives before (405) and after (410) compression is shown. A PUF having 0.063% carbon black before (415) and after (420) compression is shown. A PUF having 0.063% conventional graphene before (425) and after (430) compression is shown. A PUF having 0.063% turbostratic graphene before (435) and after (440) compression is shown.

[0148] As shown in Table 2 below, the compressive strength of four types of PUFs manufactured in example batch R according to one embodiment is measured. The thickness of each foam is measured and compared with the thickness compressed by a 2 kg load. The compressive strength (kPa) and the relative compressive strength between the foams were calculated from the measurements of the pre-load and compressed thickness of each foam.

[0149] Compressive strength of PUF in Example Batch R Ultrasonically treated additive carbon in MDI Additive-free PUF 0.063% CB / PUF 0.063% XG / PUF 0.063% TG / PUF Compressive strength (kPa) 8.6 8.5 15.3 31.1 change (%) 0.0 -1.2 78.4 262.4

[0150] As shown in Table 2, adding turbostratic graphene to PUF increases the compressive strength of the foam by 262%. Conventional graphene increases the compressive strength by 78%.

[0151] As shown in Table 3 below, the compressive strength of four types of PUFs manufactured in Example Batch H according to one embodiment is measured. The thickness of each foam is measured and compared with the thickness compressed by a small mass load of 100g. The compressive strength (kPa) and the relative compressive strength between the foams were calculated from the measurements of the preload and compression thickness of each foam.

[0152] Compressive strength of PUF in Example Batch H Ultrasonically treated additive carbon in MDI Additive-free PUF 0.063% CB / PUF 0.063% XG / PUF 0.063% TG / PUF Compressive strength (kPa) 8.5 8.2 9.3 12.2 change (%) 0.0 -3.5 9.4 43.5

[0153] As shown in Table 3, the addition of turbostratic graphene contributes to a change of more than 40% in compressive strength (which is much larger than that of conventional graphene).

[0154] Referring to FIG. 5, a graph showing the thermal conductivity of four types of polyurethane foam according to one embodiment is illustrated. The thermal conductivity of the four types of PUF is measured by placing the four types of PUF on a hot plate set to 100°C. A thermocouple probe is inserted 1 cm from the bottom of each foam to avoid problems when each foam has slightly different thicknesses. The foam temperature is recorded every 15 seconds for 2 minutes.

[0155] As shown in Table 4 below, according to one embodiment, the temperature change (dT) of the PUF after 2 minutes of heating at 100°C is measured.

[0156] Thermal conductivity of PUF in Example Batch R Ultrasonically treated additive carbon in MDI Additive-free PUF 0.063% CB / PUF 0.063% XG / PUF 0.063% TG / PUF dT after 2 minutes at To=100℃ 13.7 19.3 16.7 8.5 change (%) 0.0 -29.0 -18.0 61.2

[0157] The addition of turbostratic graphene increases the insulation of the foam by 61% compared to a baseline PUF without additives. In contrast, conventional graphene and carbon black increase thermal conductivity.

[0158] The amount of turbostratic graphene in the PUF can be increased or decreased to use a loading effect to change the thermal conductivity of the PUF.

[0159] Referring to FIG. 6, an image of a device for measuring the sound absorption characteristics of four types of polyurethane foam according to one embodiment is illustrated. The sound absorption characteristics of the four types of PUF are measured in a styrofoam box, and as shown in (605), a device such as a smartphone is placed inside the box to generate sound having three specific frequencies of 1600 Hz, 2000 Hz, and 2500 Hz within a range useful for the automotive industry. A sample of the PUF is placed in an opening on the lid of the box as shown in (610), and a second device such as a second smartphone is placed on top of the PUF. The second smartphone has sound analysis software that records sound dB.

[0160] The sound absorption properties of PUF are shown in Table 5 below.

[0161] Sound absorption of PUF in Example Batch R Ultrasonically treated additive carbon in MDI Additive-free PUF 0.063% CB / PUF 0.063% XG / PUF 0.063% TG / PUF 1.6 kHz (% sound absorption improvement) 0 -10 -30 -35 2.0 kHz (% sound absorption improvement) 0 0 44 44 2.5 kHz (% sound absorption improvement) 0 13 31 13

[0162] The sound absorption quality of PUF is highly dependent on the frequency of sound, but this is improved when carbon-based additives are added. A PUF with a turbostratic graphene content of 0.063% attenuated sound for frequencies above 2 kHz. Acoustically, turbostratic graphene was also compared to conventional graphene-based foams.

[0163] Example 2 - Turbostratic graphene dispersion

[0164] In one embodiment, turbostratic graphene is first dispersed in a liquid to break the weak surface forces holding the graphene powder together. The turbostratic graphene dispersion can be used for further dilution with various materials typically used in the manufacture of PUFs and masterbatches, such as polyol and isocyanate-containing compounds. Due to the turbostratic properties of graphene, turbostratic graphene particles with a size range of 5 nm to 2000 nm are dispersed at low energy, remain separated, and do not aggregate even after several days or years. The turbostratic graphene-liquid dispersion does not aggregate when diluted with or further mixed with other materials typically used in the manufacture of polyurethane foams and after the manufacture of masterbatches, such as polyol masterbatches or isocyanate-containing masterbatches.

[0165] Generally, turbostratic graphene dispersions have a concentration four times higher than the most concentrated conventional graphene dispersions produced by conventional liquid-phase exfoliation of graphite, and a concentration more than 10 times higher than many reported values ​​of graphene nanoplatelets (GNP).

[0166] Turbostratic graphene dispersion in water, alcohol, solvent, or oil can be achieved using ultrasonic treatment equipment or a shear mixer. For example, turbostratic graphene-water dispersion can be achieved by ultrasonic treatment for 2 to 30 minutes, or by shear mixing at 4000 rpm to 5000 rpm for 15 minutes.

[0167] In one embodiment, turbostratic graphene may be dispersed in a 1% water-pluronic (F-127) solution at various concentrations (1 to 5 mg / mL or 0.5% w / w in water). Other conventional water-compatible surfactants, such as conventional dishwashing liquid, dihydrolevoglucosenone (Cyrene), and other conventional water-compatible surfactants may also be used instead of pluronic F-127. Other water-compatible surfactant / dispersant systems for graphene dispersion include the following: sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), lithium dodecyl sulfate (LDS), sodium deoxycholate (DOC), sodium taurodeoxycholate (TDOC), cetyltrimethylammonium bromide (CTAB), tetradecyltrimethylammonium bromide (TTAB), Pluronic F87, polyvinylpyrrolidone (PVP), polyoxyethylene (40) nonylphenyl ether (CO-890), Triton X-100, Tween 20, Tween 80, polycarboylate (H14N), sodium chlorate, tetracyanoquinodimethane (TCNQ), pyridinium tribromide, N,N'-dimethyl-2,9-diazaferropyrenium divalent cation, N,N'-Dimethyl-2,7-Diazapyrene, Tetrasodium 1,3,6,8-Pyrenetetrasulfonate, 1-Pyrenemethylamine hydrochloride, 1,3,6,8-Pyrenetetrasulfonic acid tetrasodium salt hydrate, 1-Pyrenecarboxylic acid, 1-Aminopyrene, 1-Aminomethylpyrene, 1-Pyrenecarboxylic acid, 1-Pyrenebutyric acid, 1-Pyrenebutanol, 1-Pyrenesulfonic acid hydrate, 1-Pyrenesulfonic acid sodium salt, 1,3,6,8-Pyrenetetrasulfone tetrasodium salt, 6,8-Dihydroxy-1,3-Pyrenedisulfonic acid disodium salt, 8-Hydroxypyrene-1,3,6-trisulfonic acid trisodium salt, Perylenebisimide bolar-type amphiphilic medium, Tetrabutyl Ammonium hydroxide (TBA), 9-anthracene carboxylic acid.

[0168] In one embodiment, turbostratic graphene may be dispersed at various concentrations (1 to 50 mg / ml or 6.3% w / w in alcohol) in alcohols including, without limitation, methanol, ethyl alcohol, isopropyl alcohol, butanol, pentanol, ethylene glycol, propylene glycol, glycerol, and any combination thereof.

[0169] In one embodiment, turbostratic graphene may be dispersed without limitation at various concentrations (1 to 100 mg / ml or 11% w / w in organic solvent) in organic solvents including acetone, toluene, N-methyl-2-pyrrolidone (NMP), xylene, benzene, 1,2-dichlorobenzene (DCB), dimethylformamide (DMF), and methyl ethyl ketone (MEK).

[0170] Referring to FIG. 7, a turbostratic graphene-oil dispersion before (705) and after (710) three weeks of storage according to one embodiment is illustrated. The turbostratic graphene dispersion is maintained in olive oil throughout the storage period.

[0171] In one embodiment, turbostratic graphene may be dispersed in various concentrations (1 to 100 mg / ml or 11% w / w in oil) of petroleum-based oils and vegetable-based oils, such as seed oil, soybean oil, rapeseed oil, canola oil, peanut oil, cottonseed oil, sunflower oil, olive oil, grapeseed oil, linseed oil, castor oil, fish oil, algae oil, mustard seed oil, and combinations thereof. Other oils may include mineral oil, paraffinic oil, and naphthenic oil.

[0172] In one embodiment, the turbostratic graphene dispersion may be in water, alcohol, a solvent, or an oil. The turbostratic graphene dispersion may be used to prepare masterbatches, such as isocyanate-containing masterbatches and polyol masterbatches. The turbostratic graphene dispersion is shear-mixed with an isocyanate-containing material or a polyol material to prepare a masterbatch. Due to the dispersion ability of turbostratic graphene, the masterbatch may be diluted at least five times for the batch. In another embodiment, the turbostratic graphene dispersion may be further concentrated by heating, distillation, centrifugation, or by evaporating a portion of the dispersant by chemical means.

[0173] In one embodiment, turbostratic graphene is used in the preparation of masterbatches, such as isocyanate-containing masterbatches and polyol masterbatches, by directly dispersing turbostratic graphene into an isocyanate or polyol material. Optionally, the direct dispersion in the isocyanate or polyol is maintained at room temperature. Optionally, the isocyanate or polyol is heated until a desired viscosity is achieved (80°C to 100°C) to effectively disperse the turbostratic graphene.

[0174] In some embodiments, the isocyanate may include, without limitation, methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H12MDI), 1,5-naphthalene diisocyanate (NDI), tetramethylxylene diisocyanate (TMXDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CDI), tolidine diisocyanate (TODI), and combinations thereof.

[0175] In some embodiments, the polyol material may include petroleum-based polyols and bio-based polyols and combinations thereof.

[0176] Adding turbostratic graphene to PUF provides advantages that are not present when the PUF additive material is GNP. Due to the poor dispersion characteristics of GNP, it tends to aggregate and increase the viscosity of the medium. This property makes it difficult to disperse GNP into the polymer matrix without sacrificing the performance characteristics of the polymer matrix. In addition, the increased viscosity makes it more difficult to pump polyols and isocyanates from the holding tank to the dispersion nozzle.

[0177] Due to the turbostratic properties of turbostratic graphene, turbostratic graphene can be advantageously dispersed better than other types of conventional graphene, so individual graphene particles will not aggregate for several days or months. These properties can advantageously facilitate the dispersion of turbostratic graphene into a polymer matrix and improve the performance characteristics of the polymer matrix. In addition, the viscosity of the turbostratic graphene-polyol dispersion and the turbostratic graphene-isocyanate dispersion can advantageously facilitate the pumping of the turbostratic graphene-polyol dispersion and the turbostratic graphene-isocyanate dispersion from a holding tank to a dispersion nozzle.

[0178] In one embodiment, a flexible polyurethane foam can be manufactured according to a one-shot method. This procedure includes the step of preparing a turbostratic graphene-MDI mixture by mixing a turbostratic graphene dispersion, e.g., turbostratic graphene-toluene, with an isocyanate, e.g., MDI, at 1,000 to 1,500 rpm for 1 to 5 minutes. Optionally, turbostratic graphene may be dispersed in a surfactant. Optionally, turbostratic graphene may be dispersed in water, which is a blowing agent. Optionally, if the dispersant, water, alcohol, oil, or solvent is undesirable in the final foam product, the turbostratic graphene dispersion may be treated to remove the dispersant through thermal heating, distillation, or chemical methods. In one example, the turbostratic graphene concentration is 0.05% of the total weight of the polyol and MDI, and TG is introduced through the toluene dispersion. In one example, the turbostratic graphene concentration is 0.02% of the total weight of the polyol, MDI, and other chemical agents, and the turbostratic graphene is introduced through a water dispersion, where the water is 4% of the total weight.

[0179] Next, when adding a petroleum-based polyol, a bio-based polyol, or a combination thereof while stirring at 1,500 rpm for at least 10 seconds, Turbostratic graphene-MDI is mixed with a surfactant, catalyst, crosslinking agent, and foaming agent while stirring at 1,500 rpm for 10 seconds. At the 20-second mark, the mixed liquid is poured into a preheated steel mold heated to 60°C to 80°C before pouring the mixture. The PUF mixture is held in the mold for 1 to 5 minutes, after which it is demolded. After demolding, the foam can be cured in an oven at 60°C to 80°C for 1 to 2 hours.

[0180] Another example of a PUF composite with turbostratic graphene is the use of bio-based polyols. Bio-based polyols are products based on triglycerides, such as castor oil or modified soybean oil, typically referred to as natural oil polyols (NOPs). They serve as partial substitutes for petroleum-based polyols in applications including household furniture (stab stock applications), molded foams (typically automotive applications), and rigid foam applications (particularly spray foam insulation). NOPs are typically derived by functionalizing unsaturated fatty acids in natural oils to introduce hydroxyl functional groups. Some examples of NOPs include Emery 14060 and 14090 polyols.

[0181] The turbostratic graphene PUF composites and methods provided herein may be applied to commercially available foam manufacturing kits providing parts A and parts B components. Some examples of these kits include Flex Foam-iT! III, Flex Foam-iT! 7FR flexible foam (by Smooth-On), and Foam-iT! 10 slow rigid foam (by Smooth-On).

[0182] Example 3 - PUF prepared by polyol masterbatch

[0183] Referring to FIG. 8, a flowchart illustrating a method (800) for manufacturing a polyurethane foam is illustrated. The method (800) includes the step of dispersing graphene in oil at (805). The method also includes the step of chemically converting the oil into a polyol at (810). The method also includes the step of chemically converting the polyol into a polyurethane foam by adding an isocyanate at (815).

[0184] In one embodiment, graphene is dispersed in vegetable oil before chemically converting the graphene-oil dispersion into a polyol. Subsequently, a graphene PUF composite is prepared using the prepared polyol. Optionally, turbostratic graphene may be used as the selected graphene, but the graphene is not limited to turbostratic graphene. In this process, a polyurethane foam is prepared from an isocyanate and a polyol, wherein the graphene is pre-dispersed in the biopolyol.

[0185] Table 6 below shows an exemplary composition for the preparation of a biopolyol from oil having dispersed graphene according to one embodiment.

[0186] Bio-based polyol composition from graphene-soybean oil dispersion ingredient Amount (grams) Soybean oil 309.60 Turbostratic graphene 0.31 Iodine 0.60 Diethanolamine (DEA or DEOA) 58.11 Diphenylmethane diisocyanate (MDI) 155.45

[0187] In the composition of Table 6, turbostratic graphene is dispersed in soybean oil at a concentration of 0.074 wt% of the oil. The dispersion is sonicated until a uniform black solution is obtained, typically within 2 to 15 minutes. The dispersion may also be mixed using a shear mixer tool. Next, 58.11 g of diethanolamine and 0.60 g of iodine are added to the above amounts of turbostratic graphene-soybean oil dispersion while stirring. The mixture is stirred at about 90°C to about 113°C for 18 hours, and then cooled to room temperature to obtain about 368.54 g of dark liquid TG-soybean-polyol. Next, the polyol is reacted with 155.45 g of diphenylmethane diisocyanate (MDI) (wherein the turbostratic graphene concentration is 0.06% of the total weight) to produce a solid turbostratic graphene-soybean polyurethane material.

[0188] Table 7 below shows another embodiment of an oil-graphene dispersion for preparing a polyol for conversion to PUF according to one embodiment.

[0189] Bio-based polyol composition from graphene-corn oil dispersion ingredient Amount (grams) corn oil 309.60 Turbostratic graphene 0.31 Hydrochloric acid (37%) 10.0 Diethanolamine (DEA or DEOA) 58.11 Diphenylmethane diisocyanate (MDI) 155.45

[0190] In the composition of Table 7, turbostratic graphene is dispersed in corn oil at a concentration of 0.074 wt% of the oil. Hydrochloric acid is added to the turbostratic graphene-corn oil dispersion by stirring at room temperature. The mixture is heated to about 93°C and reacted at about 93°C for about 1 hour, then distilled to remove water under vacuum at about 93°C. The indicated amount of diethanolamine is added to the mixture and stirred at about 93°C to about 112°C for 40 hours, then cooled to room temperature to obtain 368.54 g of dark liquid turbostratic graphene-corn oil polyol. Subsequently, the polyol is reacted with the disclosed amount of diphenylmethane diisocyanate (MDI) (wherein the turbostratic graphene concentration is 0.06% of the total weight) to produce a solid TG-corn polyurethane material.

[0191] The provided turbostratic graphene PUF composite may be for automotive foam, but other foam applications may be implemented, including, but are not limited to, bedding, furniture, flooring, road fillers and repairs, and building construction. Other applications include urethane coatings, adhesives, sealants, epoxy, and elastomers. Other non-urethane applications may also be included, including cement and concrete manufacturing and asphalt manufacturing.

[0192] Bio-based polyols can offer advantages over petroleum-based polyols. For example, bio-based polyols allow for the use of renewable resources instead of non-renewable resources found in petroleum-based sources. Petroleum polyols also generally require more energy for manufacturing than bio-based polyols.

[0193] While the above technology provides examples of one or more devices, methods, or systems, it will be understood that other devices, methods, or systems may be within the scope of the claims as interpreted by a person skilled in the art.

Claims

Claim 1 A method for manufacturing a polyurethane foam, wherein the manufacturing method comprises: a step of dispersing turbostratic graphene synthesized through resistive Joule heating in a polymerization solution, wherein the polymerization solution comprises a first component for polymerization into a polymer; and a step of chemically converting the polymerization solution into a polyurethane foam by adding a second component for polymerization with the first component, wherein the first component and the second component are each one of a monomer and a polymer. Claim 2 A method of manufacturing according to claim 1, wherein the first component is a polyol and the second component is an isocyanate. Claim 3 A method of manufacturing according to paragraph 2, wherein the polyol is at least one of the group comprising petroleum-based polyols and bio-based polyols. Claim 4 A method for manufacturing according to claim 1, further comprising the step of dispersing the turbostratic graphene into a solvent before dispersing it into the polymerization solution, wherein the solvent comprises at least one of the group comprising an aqueous solvent, an alcohol-based solvent, an organic solvent, and an oil-based solvent. Claim 5 A manufacturing method according to claim 4, further comprising the step of heating the solvent while dispersing the turbostratic graphene into the solvent. Claim 6 A method of manufacturing according to claim 4, wherein the aqueous solvent is a water-surfactant solution. Claim 7 A manufacturing method according to claim 1, further comprising the step of heating the polymerization solution while dispersing the turbostratic graphene. Claim 8 As a polyurethane foam, the polyurethane foam comprises: turbostratic graphene synthesized through resistive Joule heating; and a polymer formed from the polymerization of a polyol and an isocyanate. Claim 9 In claim 8, the polyurethane foam having the turbostratic graphene with a particle diameter of 5 nm to 2000 nm. Claim 10 In claim 8, the polyurethane foam wherein the turbostratic graphene has an oxygen content of 0.1% to 5% based on atomic ratio. Claim 11 In claim 8, the polyurethane foam wherein the turbostratic graphene is produced by Joule heating of carbon powder. Claim 12 In claim 8, the polyurethane foam is prepared from the carbon feedstock by Joule heating the carbon feedstock to a temperature of 2800°C to 3000°C, wherein the turbostratic graphene is the turbostratic graphene. Claim 13 In paragraph 8, the polyurethane foam is a polyurethane foam used in automobile seats, bedding, furniture, flooring, road fill, or building construction. Claim 14 In claim 8, the polyurethane foam is a polyurethane foam used as a urethane coating, adhesive, sealant, epoxy, or elastomer. Claim 15 A turbostratic graphene dispersion, wherein the turbostratic graphene dispersion comprises: turbostratic graphene synthesized through resistive Joule heating; and a solvent for dispersing the turbostratic graphene, wherein the solvent for dispersing the turbostratic graphene is at least one of the group comprising an aqueous solvent, an alcohol-based solvent, an organic solvent, and an oil-based solvent. Claim 16 A turbostratic graphene dispersion according to claim 15, wherein the solvent for dispersing the turbostratic graphene is a polyol solution for conversion into polyurethane foam or an isocyanate solution for conversion into polyurethane foam. Claim 17 delete Claim 18 delete Claim 19 delete Claim 20 delete Claim 21 delete Claim 22 delete Claim 23 delete Claim 24 delete Claim 25 delete Claim 26 delete Claim 27 delete Claim 28 delete Claim 29 delete Claim 30 delete Claim 31 delete Claim 32 delete Claim 33 delete Claim 34 delete Claim 35 delete Claim 36 delete Claim 37 delete Claim 38 delete Claim 39 delete Claim 40 delete Claim 41 delete Claim 42 delete Claim 43 delete Claim 44 delete Claim 45 delete Claim 46 delete Claim 47 delete Claim 48 delete Claim 49 delete Claim 50 delete Claim 51 delete Claim 52 delete Claim 53 delete Claim 54 delete Claim 55 delete Claim 56 delete Claim 57 delete Claim 58 delete Claim 59 delete Claim 60 delete Claim 61 delete Claim 62 delete Claim 63 delete Claim 64 delete Claim 65 delete Claim 66 delete Claim 67 delete Claim 68 delete Claim 69 delete Claim 70 delete Claim 71 delete Claim 72 delete Claim 73 delete Claim 74 delete Claim 75 delete Claim 76 delete Claim 77 delete Claim 78 delete Claim 79 delete Claim 80 delete Claim 81 delete Claim 82 delete Claim 83 delete Claim 84 delete Claim 85 delete Claim 86 delete Claim 87 delete Claim 88 delete Claim 89 delete Claim 90 delete Claim 91 delete Claim 92 delete Claim 93 delete Claim 94 delete Claim 95 delete Claim 96 delete Claim 97 delete Claim 98 delete

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