Polymer composites

Abstract

Glass fiber reinforced polymer composites including three-dimensional (3D) graphene characterized by a significant increase in flexural modulus while reducing density compared to the neat polymer. A carbon reinforced polymer composite including a polymer blend including a first polymer characterized by a first flexural modulus, and a second polymer characterized by a second flexural modulus that is different from the first flexural modulus, and 3D graphene. The carbon reinforced polymer composite is characterized by a flexural modulus that is greater than the flexural modulus of the first polymer by at least 10%. A thermoplastic polyolefin (TPO) composite characterized by an increase in the density of the TPO composite of less than about 5% relative to the nominal density of the polypropylene homopolymer.

Description

POLYMER COMPOSITESRELATED APPLICATIONS

[0001] This Patent Application claims priority to U.S. Provisional Patent Application No. 63 / 530,960 entitled “COMPOSITE POLYMER BLENDS INCLUDING THREE- DIMENSIONAL (3D) GRAPHENE” and filed on August 05, 2023, to U.S. Provisional Patent Application No. 63 / 546,351 entitled “POLYMER COMPOSITES INCLUDING THREE-DIMENSIONAL GRAPHENE” and filed on October 30, 2023, to U.S. Provisional Patent Application No. 63 / 604,765 entitled “POLYMER COMPOSITES” and filed on November 30, 2023, and to U.S. Provisional Patent Application No. 63 / 679,069 entitled “POLYMER COMPOSITES” and filed on August 02, 2024, all of which are assigned to the assignee hereof. The disclosures of all prior Applications are considered part of and are incorporated by reference in this Patent Application in their respective entireties.TECHNICAL FIELD

[0002] This disclosure relates generally to polymer composites with enhanced mechanical properties, and more particularly, to lightweighted glass fiber reinforced polymer composites, carbon reinforced polymer composites, or thermoplastic polyolefin composites.DESCRIPTION OF RELATED ART

[0003] A polymer composite generally includes a polymer matrix, and one or more additives or filler materials to enhance polymer matrix-filler interface interactions and yield a composite characterized by one or more mechanical properties that are superior to that of the polymer matrix. The mechanical properties of the polymer composites may be influenced by the type of the polymer matrix, the type of filler, the concentration of the filler, the dispersion of filler in the polymer matrix, and the interfacial tension or interactions between the filler and the polymer matrix.

[0004] For example, glass fiber reinforced polymer (“GFRP”) composites, which include glass fibers as a strengthening additive, are of great interest for several applications, including automotive, aerospace, marine, or buildings. Interest in GFRP composites is motivated, in part, by properties including strong and scratch-resistant surfaces and walls that can withstand high impacts. However, due to the high density of glass, which is approximately 2.5 g / cm3, a glass fiber content of between 15 wt% and 50 wt% in the GFRP compositesresults in significantly higher GFRP composite densities compared to the pure polymer counterparts which do not include glass fibers. This undesirable increase in GFRP composite density leads to increased weight of the finished product or part, which can be detrimental in some applications including vehicular applications. For example, automotive applications require lightweight and high strength materials and components to achieve long-term cost saving and improvements in fuel efficiency. Accordingly, there is a need for novel GFRP composites including reduced glass fiber content but without sacrificing one or more mechanical properties including flexural modulus or tensile strength.

[0005] As another example, in carbon fiber reinforced polymer composites, the carbon fibers may also increase the stiffness and strength of the composite above that of the starting polymer matrix. Carbon fibers may be coated with an epoxy to improve adhesion of the fibers in the polymer matrix and dispersion of the fibers in the polymer matrix. However, there is a tradeoff between stiffness, which is an indicator of the ability of the composite material to bend and distribute a load or resist deformation, and the strength of the composite. The strength of the polymer may be characterized by its tensile strength or ultimate strength, and the stiffness by its flexural modulus. Approaches to improve this tradeoff include manipulating the density of the starting polymer matrix, adding an alpha-olefin copolymer, for example, octene copolymer in linear low-density polyethylene (“LLDPE”) or by adding one or more of glass fibers, carbon fibers, talc, mica, or graphene. There is a need for improving the stiffness of carbon reinforced composites while allowing for moldability of the material, which is driven by many applications that include one or more of travel cases, kayaks, or other watercraft. More importantly, there is a need for lightweighting composites by decreasing the wall thickness of the composite products while optimizing stiffness (which is indicative of resistance to deformation), toughness (which is indicative of resistance to impact), low temperature impact resistance, and moldability.

[0006] As another example, thermoplastic polyolefins (“TPO”) composites of polypropylene may be characterized by an increase in impact resistance relative to that of lightweight polypropylene homopolymers. TPO composite formulations typically include an elastomer or rubber, and a filler, which are added to a base polypropylene homopolymer. For example, filler materials in TPO composites may include minerals, and may increase stiffness, impact resistance, and dimensional stability even at low temperatures. These filler materials are typically high-density materials. For example, the density of calcium carbonate and talc is about 2.71 g / cc and about 2.75 g / cc, respectively, compared to the nominal densityof polypropylene homopolymer of about 0.90 g / cc. As such, even at low percentage amounts of a mineral filler in the TPO composite, the density of the TPO composite often undesirably increases beyond 0.95 g / cc and sometimes even beyond 1 g / cc. Accordingly, there is a need for lightweighting TPO composites using novel filler materials that result in a TPO composite density of less than about 0.95 g / cc, without a significant reduction in the desired mechanical properties of the TPO composites.SUMMARY

[0007] This Summary is provided to introduce in a simplified form a selection of concepts that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter.

[0008] In some implementations, a glass fiber reinforced polymer (“GFRP”) composite may include a polypropylene polymer, glass fibers, polypropylene-graft-maleic anhydride (“PPgMA”), and three-dimensional (“3D”) graphene. In some implementations, the ratio of a flexural modulus of the glass fiber reinforced polymer composite to the flexural modulus of the polypropylene polymer is between about 2 and about 3. In some other implementations, the GFRP composite may include about 30 wt% glass fibers, about 2 wt% PPgMA, and about 2 wt% 3D graphene dispersed in the polypropylene polymer. In some implementations, the glass fibers may include surface amine functional groups generated by treating the glass fibers with 3-aminopropyl) triethoxysilane (“APTES”). In some other implementations, 3D graphene may include surface oxygen functional groups generated by ozone treatment of 3D graphene.

[0009] In some implementations, a carbon reinforced polymer composite may include a polymer blend including a first polymer characterized by a first flexural modulus, and a second polymer characterized by a second flexural modulus that is different from the first flexural modulus, polyethylene-graft-maleic anhydride (“PEgMA”), and 3D graphene, wherein the composite is characterized by a third flexural modulus that is greater than the first flexural modulus by at least 10%. In some implementations, a first polymer of the one or more polymers includes linear low-density polyethylene (“LLDPE”), and a second polymer of the one or more polymers includes an alpha-olefin copolymer. In some implementations, an alpha-olefin copolymer may include octene alpha-olefin LLDPE copolymer. In some other implementations, a carbon reinforced polymer composite may further include an antioxidant additive. In some other implementations, an antioxidantadditive may include one or more of sterically hindered phenols, secondary aromatic amines, phosphites, thioethers, or any combination thereof.

[0010] In some implementations, 3D graphene associated with the example polymer composites may include porous carbon agglomerates including a plurality of graphene layers. In some instances, a number of graphene layers in the plurality of graphene layers may be between 10 and 15. In some other instances, 3D graphene may include surface oxygen functional groups. In some instances, a ratio of the concentration of oxygen (at%) associated with C=O groups to the concentration of oxygen (at%) associated with C-0 groups may be between approximately 5 and 6. In some implementations, 3D graphene may include surface silanol (Si-O-H) functional groups. In some instances, a silicon content associated with 3D graphene including surface silanol functional groups may be between approximately 5 at% and approximately 10 at%. In some other instances, an oxygen content associated with in 3D graphene including surface silanol functional groups may be between approximately 2 at% and approximately 8 at%. In some instances, a BET surface area associated with 3D graphene including surface silanol functional groups may be between approximately 100 m2 / g and approximately 150 m2 / g.

[0011] In some implementations, 3D graphene associated with the example polymer composites may include porous carbon agglomerates of porous carbon primary nanoparticles including one or more interconnected bundles of electrically conductive graphene layers. In some other implementations, each graphene layer may be characterized by a linear dimension of between approximately 50 nm and 200 nm. In some other implementations, the graphene layers may include one or more of single layer graphene (“SLG”), few layer graphene (“FLG”), or many layer graphene (“MLG”). In some implementations, the graphene layers may be arranged as one or more stacks connected to each other and defining a 3D porous scaffold structure including mesopores. In some implementations, the one or more stacks may be disposed substantially orthogonal to each other.

[0012] In some implementations, 3D graphene may include porous carbon agglomerates of porous carbon primary nanoparticles. A respective porous carbon primary nanoparticle may include an inner porous shell disposed about a center of the respective porous carbon primary nanoparticle and enclosing an inner porous carbon region, an outer porous shell enclosing an outer porous carbon region disposed between the inner porous shell and the outer porous shell, and an interconnected porous network disposed in and in fluid communication with the inner and outer porous carbon regions. In some implementations,the inner porous carbon region and the outer porous carbon region may be characterized by an average pore size and an average pore density associated with each region. In some other implementations, the average pore size decreases along a radial direction from the center to the outer porous shell.

[0013] In some other implementations, an example thermoplastic polyolefin (“TPO”) composite may include a polypropylene homopolymer, a polypropylene copolymer and an elastomer. In some aspects, an increase in the density of an example TPO composite as measured under ASTM D.792 may be less than about 5% relative to the nominal density of the polypropylene homopolymer. In some implementations, an example TPO composite may further include a carbon material including one or more of graphite, amorphous carbon, fullerene, carbon nanotubes, single layer graphene (“SLG”), few layer graphene (“FLG”), 3D graphene, or many layer graphene (“MLG”). In some implementations, a loading of the carbon material in the TPO composite may be less than or equal to about 0.5 wt%. In some implementations, an example TPO composite does not include a polypropylene-graft-maleic anhydride (PP-g-MA) compatibilizer.

[0014] Details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims. Note that the relative dimensions of the following figures may not be drawn to scale.BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1A shows a schematic diagram of a mesoporous carbon nanoparticle in three-dimensional (“3D”) graphene, according to some implementations.

[0016] Figure IB shows a scanning electron microscopy (“SEM”) micrograph of agglomerates of porous carbon primary nanoparticles including 3D graphene, according to some implementations.

[0017] Figure 1C shows a transmission electron microscopy (“TEM”) micrograph of agglomerates of porous carbon primary nanoparticles including 3D graphene, according to some implementations.

[0018] Figure 2 shows TEM micrographs of wavy and / or wrinkled graphene formed during microwave treatment of hydrocarbon feedstock, according to some implementations.

[0019] Figure 3 shows a SEM micrograph of example agglomerates of porous carbon nanoparticles in 3D graphene, according to some implementations.

[0020] Figure 4 shows an illustrative flow chart depicting an example operation for forming glass fiber reinforced polymer (“GFRP”) composites including graphene, according to some implementations.

[0021] Figure 5A shows a schematic diagram of covalent interaction between 3D graphene including surface oxygen functional groups and amine-functionalized glass fibers in GFRP composites, according to some implementations.

[0022] Figure 5B shows a schematic diagram of covalent interaction between PPgMA and 3D graphene including surface oxygen functional groups in GFRP composites, according to some implementations.

[0023] Figure 5C shows a schematic diagram of covalent interaction between PPgMA and amine-functionalized glass fibers in GFRP composites, according to some implementations .

[0024] Figure 5D shows a schematic diagram of physical interaction between PPgMA and polypropylene matrix in GFRP composites, according to some implementations.

[0025] Figure 6 shows a comparison of the mechanical properties of various compositions of glass fiber reinforced polymer composites, according to some implementations .

[0026] Figure 7 shows SEM micrographs of example GFRP composites including 3D graphene, according to some implementations.

[0027] Figure 8A shows a schematic diagram of an example porous carbon primary nanoparticle, according to some implementations.

[0028] Figure 8B shows a transmission electron microscopy (“TEM”) micrograph of aggregates of porous primary nanoparticles, according to some implementations.

[0029] Figure 8C shows a TEM micrograph of porous carbon agglomerates of porous primary carbon nanoparticles, according to some implementations.

[0030] Figure 8D shows a TEM micrograph of surface etched agglomerates of porous primary carbon nanoparticles, according to some implementations.

[0031] Figure 9A shows a schematic diagram of a tri-zone porous carbon primary nanoparticle, according to some implementations.

[0032] Figure 9B shows an example pore size variation representative of a tri-zone porous carbon primary nanoparticle of Figure 9A, according to some implementations.

[0033] Figure 10 shows a graph illustrating pore volume versus pore size of an example porous carbon primary nanoparticle, according to some implementations.

[0034] Figure 11 A shows a show TEM micrograph of example porous carbon agglomerates of porous carbon primary nanoparticles in 3D graphene, according to some implementations .

[0035] Figure 1 IB shows another TEM micrograph of porous carbon agglomerates of porous carbon primary nanoparticles in 3D graphene, according to some implementations.

[0036] Figure 12 shows a graph depicting cumulative pore volume versus pore size of micropores and mesopores dispersed throughout porous carbon primary nanoparticles particles, according to some implementations.

[0037] Figure 13A shows a schematic representation of example porous carbon agglomerates, according to some implementations.

[0038] Figures 13B-13C show scanning electron microscopy (“SEM”) micrographs of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons, according to some implementations.

[0039] Figure 13D shows a transmission electron microscopy (“TEM”) micrograph of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons, according to some implementations.

[0040] Figure 13E shows a scanning transmission electron microscopy (“STEM”) micrograph of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons, according to some implementations.

[0041] Figure 13F shows an electron energy loss spectroscopy (“TEM-EELS”) micrograph of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons, according to some implementations.

[0042] Figure 14 shows a graph which provides a comparison of the flexural modulus of linear low-density polyethylene (“LLDPE”) with that of several example carbon reinforced polymer composites, according to some implementations.

[0043] Figure 15 shows a graph which provides a comparison of the tensile strength and elongation at break of LLDPE with that of several example carbon reinforced polymer composites, according to some implementations.

[0044] Figure 16A shows a scanning electron microscopy (“SEM”) micrograph of porous carbon agglomerates of porous carbon primary nanoparticles including 3D graphene, according to some implementations.

[0045] Figure 16B shows a SEM micrograph of 2-dimensional graphene nanoplatelets, according to some implementations.

[0046] Figure 16C shows a SEM micrograph of single layer graphene flakes, according to some implementations.

[0047] Like reference numbers and designations in the various drawings indicate like elements.DETAILED DESCRIPTION

[0048] The following description is directed to some example implementations for the purposes of describing innovative aspects of this disclosure. However, a person having ordinary skill in the art will readily recognize that the teachings herein can be applied in a multitude of different ways. The described implementations can be implemented in any type of material and can be used to provide a formative material used to protect cases, coolers, phones, flashlights, travel gear, luggage, drinkware, backpacks, or the like. As such, the disclosed implementations are not to be limited by the examples provided herein, but rather encompass all implementations contemplated by the attached claims. Additionally, well- known elements of the disclosure will not be described in detail or will be omitted so as not to obscure the relevant details of the disclosure.

[0049] Composite materials may be applied in a wide array of end-use application areas, such as sensing, actuation, computation, and communication into composites (“robotic materials”), or other similar non-limiting example applications. Composite materials may also be used in constructing and / or forming buildings, bridges, structures (e.g., boat hulls and swimming pool panels), racing car bodies, shower stalls, bathtubs, storage tanks, imitation granite, cultured marble sinks and countertops, or the like. Composite materials may be used in general automotive applications, such as exposed paneling and impact absorption (e.g., for bumpers). Some composite materials may be produced for spacecraft and / or aircraft, which may travel at more than 1,000 miles per hour in demanding environments, such as outer space.

[0050] In some aspects, the composite material may be post-processed by injection molding and used as a formative material for cases, coolers, phone cases, flashlights, travel gear, luggage, drinkware, backpacks, or other similar non-limiting example applications. Inaddition, composite materials may be used as a formative material in a variety of end-use application areas in several industries, including but not limited to, agriculture, construction, floor cleaning machinery, water treatment, outdoor (e.g., lawn and garden), environmental products, marine, aerospace, recreational equipment, sporting equipment, toys, furniture, medical, consumer articles, large containers, tanks, boxes, or the like. In some instances, fabrication methods used to produce the composite material include rotational molding, injection molding, blow molding, vacuum forming, thermoforming, extrusion, additive manufacturing (e.g., 3D printing), polymer casting, or another appropriate fabrication method.

[0051] In some implementations, glass fiber reinforced polymer (“GFRP”) composites including graphene may reduce the glass fiber content in the composites, thereby reducing the density of the composites while increasing one or more of flexural modulus and tensile strength. Interleaving stiff and brittle epoxy-based carbon materials including graphene in flexible thermoplastic polymers may increase the toughness of composite materials, and thus increase impact resistance. Composite materials may include various types or classes, such as sandwich- structured composite materials, which may be formed by attaching two relatively thin and stiff skins to a lightweight and thick core. The addition of graphene to GFRP composites may also increase electrical conductivity, thermal conductivity, and durability of the composites. However, adding graphene to GFRP composites is challenging due to the structural differences of graphene compared to organic polymers. As such, to realize the benefits of including graphene in GFRP composites, achieving a good dispersibility of graphene in a polymer matrix is required.

[0052] Aspects of the present disclosure recognize that certain composite materials including GFRP composites, carbon reinforced composites, or thermoplastic polyolefin composites may benefit from uniformly incorporating graphene in various polymer blends. Unfortunately, relatively high carbon loading levels, for example, greater than 10 wt% carbon loading levels, may result in undesirable aggregation (e.g., clumping) of carbon, which may result in uncontrolled increases in viscosity and exceed targeted rheological specifications associated with post-processing of composite materials. The relatively unpredictable and uncontrollable aggregation of carbon may undesirably change physical properties (e.g., toughness) of the composite materials.Glass Fiber Reinforced Polymer Composites including 3D Graphene

[0053] In some implementations, GFRP composites including three-dimensional (“3D”) graphene and a polypropylene polymer matrix may include one or more of surface functionalized 3D graphene or a compatibilizer including polypropylene-graft-maleic anhydride (“PPgMA”). In some implementations, GFRP composites may include surface functionalized glass fibers.

[0054] In this disclosure, a primary carbon nanoparticle may include a spheroidal shaped, non-discreet component or building block of an aggregate, separable from the aggregate only by fracturing. A plurality of primary carbon nanoparticles produced by one or more methods including thermal cracking of a hydrocarbon gas, may be coalesced, or joined to form aggregates of primary carbon nanoparticles. A carbon aggregate may be considered as a discrete, colloidal entity that is the smallest dispersible unit, composed of coalesced primary carbon nanoparticles. The primary carbon nanoparticles may be connected together by one or more of van der Waals forces, covalent bonds, ionic bonds, metallic bonds, or by other physical or chemical interactions. A plurality of aggregates may be considered as an agglomerate. Agglomerates of primary carbon nanoparticles may be produced using one or more methods including thermal cracking of a hydrocarbon gas. An example porous carbon agglomerate of primary carbon nanoparticles may be characterized by a principal dimension of at least about 1 pm.

[0055] In this disclosure, “graphene” refers to an allotrope of carbon in the form of atomic-scale, hexagonal lattice in which one atom forms each vertex. The carbon atoms in graphene may be sp2hybridized carbon atoms. Additionally, graphene has a Raman spectrum with two main peaks: a G-mode at approximately 1580 cm'1and a D mode at approximately 1350 cm'1(when using a 532 nm excitation laser). Graphene may be characterized by a Raman spectroscopy signature having an ID / IG ratio between approximately 0.95 and approximately 1.05.

[0056] In some implementations, an example GFRP including graphene may include a polymer matrix and additives including 3D graphene (as described below in this disclosure), a compatibilizer, and functionalized glass fiber. The polymer matrix may include polypropylene. The compatibilizer may include PPgMA. 3D graphene may be oxidized to form surface oxygen functional groups disposed on the carbon atoms of 3D graphene. Glass fibers may also be functionalized. In some implementations, (3 -aminopropyl) triethoxysilane (“APTES”) may be used to functionalize glass fibers to form an amine film on the surfaces of the glass fibers to improve the interaction between glass fibers and the polymer matrix. Thefunctionalized glass fibers may be coated with a polypropylene film via hydrolysis and condensation.

[0057] In some implementations, 3D graphene may be oxidized using ozone. In some implementations, the oxygen containing surface functional groups on 3D graphene may include one or more of epoxide (C-O-C), hydroxyl (-OH), ether (C-O-C), ketone (O-C=O), or carboxylic acid (-COOH) groups.

[0058] As described below, in some implementations, 3D graphene may include porous carbon agglomerates of porous carbon primary nanoparticles including one or more interconnected bundles of electrically conductive graphene layers. In some implementations, the graphene layers may be arranged as one or more stacks connected to each other and defining a 3D porous scaffold structure including a mesoporous interconnected porous network. In some implementations, the one or more stacks of graphene layers may be disposed substantially orthogonal to each other. In some implementations, the graphene layers may be characterized by a linear dimension of between approximately 50 nm and 200 nm. In some other implementations, the graphene layers may include one or more of single layer graphene (SLG), few layer graphene (“FLG”), or many layer graphene (“MLG”).

[0059] Figure 1A shows a schematic diagram of a mesoporous carbon nanoparticle 100A in three-dimensional (“3D”) graphene, according to some implementations. Mesoporous nanoparticle 100A may include an interconnected bundle of electrically conductive graphene layers arranged to form a 3D open porous scaffold structure. Nanoparticle 100A and porous carbon agglomerates including nanoparticles 100 A may be produced using a high throughput, low-cost, cracking of a hydrocarbon gas such as natural gas, in an atmospheric microwave plasma reactor. An example microwave plasma reactor is disclosed in commonly-owned U.S. Pat. No. 9,767,992, which is incorporated by reference herein in its entirety. For example, the agglomerates may be formed in-flight and grown by adding additional carbonbased materials derived from incoming carbon-containing gas within a microwave-plasma reaction chamber.

[0060] The carbon nanoparticles 100A may include three-dimensional (“3D”) multimodal mesoporous carbon nanoparticles. A mesoporous material, as generally understood and as referred to herein, includes a material containing pores with diameters between 2 nm and 50 nm, according to IUPAC nomenclature. For the purposes of comparison, IUPAC defines microporous material as a material having pores smaller than 2 nm in diameter and defines macroporous material as a material having pores larger than 50 nm in diameter. In some instances, mesoporous carbon particle 100A may be characterized by a three-dimensional (“3D”) hierarchical porous structure including pores 180. In some aspects, at least a portion of the hierarchical porous structure may further define a 3D open porous scaffold structure 181.

[0061] The nanoparticles 100A may include one or more interconnected bundles 182 of electrically conductive graphene layers or sheets. Each interconnected bundle 182 may include one or more stacks 183 of graphene layers. Each stack 183 may include a plurality of graphene layers 186 that are generally stacked horizontally as more clearly shown in stack 184. One or more stacks 183 of graphene layers 186 may be arranged to form a 3D porous scaffold structure 181 including mesopores. That is, a plurality of stacks 183 of electrically conductive graphene layers 186 may be sintered together to define the 3D open porous scaffold structure 181 (which includes mesopores 180 in the example of Figure 1A). In some implementations, one or more of the stacks 183 may be connected substantially orthogonal to each other. The open porous scaffold structure 181 may be configured to provide electrical conduction between contact points (not shown for simplicity) of the stacks of graphene layers 186. In some implementations, each graphene layer 186 may be characterized by a diameter or linear dimension (“La”) of between about 50 nm to about 200 nm. In some implementations, graphene stack 483 may include few layer graphene (“FLG”), which may be composed of 5 to 15 layers of graphene.

[0062] A plurality of porous carbon primary nanoparticles 100A may be coalesced or joined to form porous carbon agglomerates of porous carbon primary nanoparticles. In this disclosure, three-dimensional graphene (“3D graphene”) includes porous carbon agglomerates of mesoporous nanoparticles 100A. In some implementations, the example 3D graphene described herein may be characterized by a Brunauer-Emmett-Teller (“BET”) surface area measured using nitrogen gas of about 50 to 300 m2 / g. In some implementations, 3D graphene may be characterized by a graphene to amorphous carbon ratio of between about 1% and about 95%. In some implementations, 3D graphene may be characterized by a carbon purity of at least 99.9%. In some implementations, 3D graphene may be characterized by an electrical conductivity of between about 500 S / m and about 20,000 S / m when compressed at pressure of about 12,000 pounds per square inch (“psi”).

[0063] In some implementations, the porous carbon primary nanoparticles 100A may include a plurality of interconnected crinkled 3D graphene sheets, a plurality of non-hollow carbon spherical particles (“NHCS”), flat graphene, wrinkled graphene, or a plurality of carbon nano-onions (“CNOs”). In some implementations, the porous carbon primary nanoparticles 100A may include wavy or flexible graphene layers that resemble crinkledpaper and may be produced using micro wave processes. The graphene layers may be flexible as they may be fused with each other at sp3type defects in a sp2graphene lattice structure.

[0064] Figure IB shows a scanning electron microscopy (“SEM”) micrograph 100B of agglomerates 102 of porous carbon primary nanoparticles including 3D graphene, according to some implementations. In some implementations, plasma-based processing conditions, e.g., as applied or performed in a microwave reactor, may be adjusted with a high degree of tunability to achieve graphene-on-graphene densification to yield the agglomerate 102. Agglomerate 102 may be surface etched using methods including CO2 etching to create pores on the external surface of the agglomerate 102 and to increase the surface area of the agglomerate 102.

[0065] Figure 1C shows a transmission electron microscopy (“TEM”) micrograph 100C of agglomerates 104 of porous carbon primary nanoparticles including 3D graphene, according to some implementations. In the agglomerates 104, 3D few-layer graphene (“FLG”) structures 106 may be seen at a 50 nm scale. FLG may refer to about 10 layers of graphene generally configured in a stacked orientation. Plasma-based processing conditions, e.g., as applied or performed in a reactor such as a microwave reactor, may be adjusted with a high degree of tunability to achieve 3D graphene by graphene-on-graphene densification.

[0066] Figure 2 shows micrographs 200 of wavy and / or wrinkled graphene 205 formed during microwave treatment of hydrocarbon feedstock, according to some implementations. In some instances, at least some of the wavy and / or wrinkled graphene 205 may coalesce with one or more additional instances of itself to produce at least some of the carbon particles in the example 3D graphene additives. In some aspects, at least some graphene layers of the microwave-energy based wavy and / or wrinkled graphene 205 may adjoin together to define various ridges and valleys 215. In this way, at least some of the ridges and valleys 215 may produce areas of increased flexibility within the wavy and / or wrinkled graphene 205, which may be suitable for infiltration by, for example, a polymeric compatibilizer including polypropylene-graft-maleic anhydride (“PPgMA”).

[0067] Figure 3 shows a micrograph of example agglomerates 305 of porous carbon nanoparticles in 3D graphene, according to some implementations. At least some of the agglomerates 305 may be formed upon coalescence of wavy and / or wrinkled graphene produced by microwave-energy assisted cracking of hydrocarbons. In some instances, the agglomerates 305 may be separated from one another by a first multitude of pores 310 formed between adjacent instances of the agglomerates 305. As shown in Figure 3, each of the agglomerates 305 may include a porous structure including an interconnect porousnetwork (e.g., including a second multitude of pores 320) produced by overlapping smaller agglomerates 315. In various implementations, an average size of the first multitude of pores 310 may be larger than an average size of the second multitude of pores 320. In various implementations, the second multitude of pores may be large enough to enable compatibilizers including PPgMA molecules to infiltrate at least some of the agglomerates 305 to produce, for example, the composite materials described herein.

[0068] In some implementations, 3D graphene as disclosed above, may include a plurality of carbon particles wherein at least some of carbon particles may include exposed carbon surfaces oxidized with one or more oxygen-containing groups and bonded to adjacent PPgMA molecules. Without being bound by any particular theory, oxidation of at least some of the carbon surfaces in 3D graphene may increase chemical bonding between at least some of the PPgMA molecules with adjacent carbon atoms in the GFRP including 3D graphene. Other graphene surface functionalization methods may be used to enhance polymer matrixgraphene interface interactions to achieve a uniform dispersion of the 3D graphene additives in the polymer matrix. As previously described, the polymer matrix in the GFRP composites may include polypropylene.

[0069] Figure 4 shows an illustrative flow chart depicting an example operation 400 for forming glass fiber reinforced polymer composites including 3D graphene, according to some implementations. In some instances, operation 400 may begin at 402 with producing 3D graphene including oxygen surface functional groups by oxidizing 3D graphene as disclosed herein with ozone. In some instances, 3D graphene may be subjected to ozone treatment in a fluidized bed reactor. The surface oxygen functional groups may include epoxy, hydroxy, or carboxylic groups. Operation 400 may continue at 404 with producing surface functionalized glass fibers by treating glass fibers in a silane solution. In some implementations, the silane solution may include of (3 -aminopropyl) triethoxysilane (“APTES”). In some instances, glass fibers may be submerged in a dilute APTES solution in ethanol, dried at ambient temperature between about 6 h and about 12 h to allow for silane condensation and cured at about 60 °C for between about 6 h and about 12 h to form an amine film on the glass fibers and to remove residual solvent. Operation 400 may continue at 406 with forming the GFRP composites including 3D graphene by mixing or compounding functionalized 3D graphene, functionalized glass fibers, PPgMA and polypropylene at between about 180 °C and about 200 °C. In some implementations, mixing at 406 may be done using a twin-screw mixer. In some implementations, one or more peroxide initiators may be added during compounding at 406.

[0070] Without being bound by any particular theory, the polypropylene matrix including oxidized 3D graphene, amino-surface functionalized glass fibers and PPgMA may result in ternary and binary hybrids (that is, joined covalently hybridized) of the respective constituents, which in turn, may synergistically improves the mechanical properties of the GFRP composites including 3D graphene.

[0071] Figure 5A shows a schematic diagram 500A of covalent interaction between 3D graphene including surface oxygen functional groups and amine-functionalized glass fibers in GFRP composites, according to some implementations. In some instances, 3D graphene may be treated with ozone as previously described. The covalent interaction may open the epoxide group on the ozone-treated 3DG graphene 501A by the amine group on the surface of glass fiber 502A.

[0072] Figure 5B shows a schematic diagram 500B of covalent interaction between PPgMA and 3D graphene including surface oxygen functional groups in GFRP composites, according to some implementations. In some instances, 3D graphene may be treated with ozone as previously described. In some instances, the interaction between PPgMA 503B and hydroxyl surface groups on 3D graphene 502B may ring-open the grafted maleic anhydride.

[0073] Figure 5C shows a schematic diagram 500C of covalent interaction between PPgMA and amine-functionalized glass fibers in GFRP composites, according to some implementations. In some instances, 3D graphene may be treated with ozone as previously described. In some instances, the amine group in the amine-functionalized glass fiber 502C may interact with maleic anhydride group of PPgMA 503C.

[0074] Figure 5D shows a schematic diagram 500D of physical interaction between PPgMA and polypropylene matrix in GFRP composites, according to some implementations. In some instances, the physical interaction may include hydrophobic -hydrophobic interaction between the polypropylene matrix 504D and polypropylene groups in PPgMA 503D.

[0075] Figure 6 shows a tabular comparison 600 of the mechanical properties of various compositions of glass fiber reinforced polymer composites, according to some implementations. A baseline GFRP composite includes 40% glass fiber (“GF”) and about 2 wt% PPgMA in a polypropylene matrix. The baseline GFRP composite was characterized by a flexural modulus of about 735,431 psi, a tensile strength of about 7207 psi, and a density of about 1.21 g / cc. The flexural modulus is indicative of the stiffness of the composite. The flexural modulus may be measured at a temperature of 23 °C under ASTM D.790 at a 1% secant modulus value. Decreasing the glass fiber content from about 40 wt% to about 30 wt% relative to the baseline GFRP composite decreased the density from about 1.2 g / cc toabout 1.14 g / cc, but also decreased the flexural modulus of the composite from about 735, 431 psi to about 609,289 psi.

[0076] Three modifications to the 30% glass fiber GFRP composite were evaluated to improve mechanical strength at lower densities, namely, (a) adding about 2 wt% 3D graphene (“XT”) prior to compounding with the polypropylene matrix including about 2 wt% PPgMa (“MODI”), (b) functionalizing the glass fibers using APTES prior to compounding with the polypropylene matrix including about 2 wt% PPgMA (“M0D2”), (b) functionalizing the glass fibers using APTES and adding about 2 wt% ozone treated 3D graphene (“O3-XT”) prior to compounding with the polypropylene matrix and about 2 wt% PPgMa (“M0D3”).

[0077] The “MODI” GFRP composite was characterized by a lower density of about 1.14 g / cc and a decrease in flexural modulus by about 4% related to the baseline GFRP composite. Additionally, the ratio of the flexural modulus of the “MODI” GFRP composite to that of polypropylene is about 2.4. In some implementations, the ratio of the flexural modulus of the “MODI” GFRP composite to that of polypropylene between about 2 and about 3. In some implementations, the flexural modulus of the glass fiber reinforced polymer composite “MODI” is about 710,000 psi. The “MODI” GFRP composite was characterized by a density of about 1.14 g / cc.

[0078] The “M0D2” GFRP composite was characterized by an increase in flexural modulus by about 3% relative to the baseline GFRP composite. The “M0D3” GFRP composite was characterized by a lower density of about 1.13 g / cc and an increase in flexural modulus by about 7% relative to the baseline GFRP composite. As such., the “M0D3” GFRP composite supports lightweighting and increase in stiffness over the baseline composite. The “M0D3” composite highlights the synergistic effects of using oxidized 3D graphene in conjunction with functionalized glass fibers in improving the mechanical properties of GFRP polymer composites. The ratio of the flexural modulus of the M0D3 glass fiber reinforced polymer composite to that of polypropylene is about 2.7. In some implementations, the ratio of the flexural modulus of the glass fiber reinforced polymer “M0D3” composite to that of polypropylene is between about 2 and about 3. In some implementations, the flexural modulus of the glass fiber reinforced polymer composite “M0D3” is about 790,000 psi. In some implementations, the tensile strength of the glass fiber reinforced polymer composite “M0D3” is about 9000 psi.

[0079] Figure 7 shows the SEM micrographs 700 of example GFRP composites including 3D graphene, according to some implementations. SEM micrograph 701 is associated with the “MODI” composite as previously described with reference to Figure 6.SEM micrograph 702 is associated with the “M0D3” composite as previously described with reference to Figure 6. SEM micrograph 701 shows localized 3D graphene as darker regions 701A in the composite. On the other hand, SEM micrograph 702 shows well distributed dark regions 702A indicating a relatively more uniform dispersion of 3D graphene in the composite matrix. Without being bound by any particular theory, the “jointly covalently hybridized” constituents of the “M0D3” GFRP composite synergistically work to improve uniform dispersion of 3D graphene in the GFRP composite matrix and subsequently improve the mechanical properties of the GFRP composites while supporting lightweighting.

[0080] In some implementations, glass fibers may be functionalized with mercapto silanes or vinyl silanes prior to compounding with the polypropylene polymer matrix to form any one of the GFRP composites as previously described. In some implementations, the example GFRP composites may include one or more of Nylon 6, Nylon 66, polycarbonates, or polypropylene polymer matrix materials.

[0081] In some implementations, 3D graphene may include porous carbon agglomerates including porous primary carbon nanoparticles, which may resemble carbon nano-onions (CNOs). As described below with reference to Figure 8 A, the porous primary carbon nanoparticles may each include an inner porous shell disposed about a center of the respective porous carbon primary nanoparticle and enclosing an inner porous carbon region, an outer porous shell enclosing an outer porous carbon region disposed between the inner porous shell and the outer porous shell, and an interconnected porous network disposed in and in fluid communication with the inner and outer porous carbon regions. In some implementations, the inner porous carbon region and the outer porous carbon region may be characterized by an average pore size and an average pore density associated with each region. In some implementations, the average pore size may decrease along a radial direction from the center to the outer porous shell. In some other implementations, the porous primary carbon nanoparticles may further include one or more intermediate porous shells disposed between the inner porous shell and the outer porous shell, wherein each of the intermediate porous shells encloses a respective intermediate porous carbon region.

[0082] In some implementations, the porous carbon agglomerates including CNO type porous primary carbon nanoparticles may be characterized by a Raman spectroscopy signature having an ID / IG ratio between approximately 0.95 and 1.05. In some implementations, the porous carbon agglomerates may be characterized by a Brunauer- Emmett-Teller (“BET”) surface area between approximately 50 m2 / g and approximately 300 m2 / g measured using nitrogen gas. In some other implementations, the porous carbonagglomerates may be characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi).

[0083] Figure 8A shows a schematic diagram 800A of an example porous carbon primary nanoparticle 805 including 3D graphene, according to some implementations. As shown in the example of Figure 8A, the porous primary carbon nanoparticle 805 may include a core (inner) porous carbon region 811 defined by a first porosity and enclosed within an inner porous shell 813. The inner porous carbon region 811, which may also be referred to herein as the first porosity region, may include a plurality of first pores 801 dispersed therein. An outer porous carbon region 812, which may also be referred to herein as the second porosity region, may be disposed between the inner porous shell 813 and an outer porous shell 810 and may include a plurality of second pores 802 dispersed therein. The inner porous carbon region 811 and the outer porous carbon region 812 may be interconnected by one or more of the first pores 801 or one or more of the second pores 802, thereby interconnecting the first and second porosity regions. That is, the inner porous carbon region 811 may be configured to be in fluid communication with the outer porous carbon region 812 through an interconnected porous network. The inner porous carbon region 811 may be defined by a first pore density, and the outer porous carbon region 812 may be defined by a second pore density that is similar to or different than the first pore density.

[0084] Example porous primary carbon nanoparticle 805 may be characterized by an average size or principal dimension (diameter, length, width) of less than approximately 200 nm. In some implementations, an average pore size may gradually decrease along a radial direction from the center 816 of the nanoparticle 805 to the outer boundary 813 of the nanoparticle 805. In some implementations, porous primary carbon nanoparticle 805 may be characterized by a range of pore sizes and pore distributions in each region.

[0085] Figure 8B shows a transmission electron microscopy (“TEM”) micrograph 800B of aggregates 840 of porous primary nanoparticles 805 including 3D graphene, according to some implementations. Those skilled in the art will appreciate that the micrographs are shown by way of example only, and that other scales may exist without departing from the scope and spirit of the present implementations. Example carbon aggregates 840 may include an interconnected porous network disposed between adjacent carbon nanoparticles 805. Aggregate 840 may include a plurality of porous carbon primary nanoparticles 805 and, in some instances, may resemble a “string-of-pearls.” In some implementations, the size or principal dimension of aggregate 840 may be between about 50 nm and 500 nm.

[0086] Figure 8C shows a TEM micrograph 800C of agglomerates of porous primary carbon nanoparticles including 3D graphene, according to some implementations. An agglomerate 845 of porous carbon primary nanoparticles 805 may be characterized by a surface area of less than about 3000 m2 / g. In some implementations, an example agglomerates 845 may be spherical in shape. In some implementations, an agglomerate 845 may be of any shape, including one or more of spherical, spheroidal, dumbbell, cylindrical, elongated cylindrical type, rectangular prism, disk, wire, or irregular.

[0087] Figure 8D shows a TEM micrograph 800D of surface etched agglomerates 842 of porous primary carbon nanoparticles including 3D graphene, according to some implementations. Example agglomerates 845 may be surface etched using methods that include CO2 etching to create pores on the external surface of the agglomerates 845 and to increase the surface area of the carbon agglomerates 845 to yield surface etched agglomerates 842. After etching, the surface etched agglomerates 842 may include three-dimensional graphene carbons (“3DG carbons”) including graphene layers interconnected as three- dimensional (“3D”) graphene structures (not shown for simplicity). The surface etched agglomerates 842 of porous primary carbon nanoparticles may be characterized by a Raman spectroscopy signature with an ID / IG ratio of approximately between 0.95 and 1.05. As previously noted, the surface etched agglomerates 842 may be assembled as rigid porous carbon agglomerates by processes including spray drying.

[0088] In some implementations, the carbon agglomerates including 3D graphene may be produced by thermal cracking of hydrocarbon feedstock as disclosed in commonly owned U.S. Pat. No. 9,862,602, U.S. Pat. No. 10,112,837, U.S. Pat. No. 11,053,121, and / or U.S. Pat. Pub. No. 2021 / 0292170, all of which are incorporated by reference herein in each of their entireties.

[0089] In some implementations, the porous carbon agglomerates may include tri-zone porous carbon primary nanoparticles. Figure 9A shows a schematic diagram of another porous carbon primary nanoparticle 900A including 3D graphene, according to some implementations. The tri-zone particle 900A may include three discrete zones such as (but not limited to) a first zone 901, a second zone 902, and a third zone 903. In some respects, each of the zones 901-903 surrounds and / or encapsulates a preceding zone. For example, the first zone 901 may be surrounded by or encapsulated by the second zone 902, and the second zone 902 may be surrounded by or encapsulated by the third zone 903. The first zone 901 may correspond to an inner region of the tri-zone particle 900A, the second zone 902 may correspond to an intermediate transition region of the tri-zone particle 900A, and the thirdzone 903 may correspond to an outer region of the tri-zone particle 900A. In some respects, the tri-zone particle 900A may include a permeable shell 855 that deforms in response to contact with one or more adjacent non-tri-zone particles and / or tri-zone particles 500A.

[0090] In some implementations, the first zone 901 may have a relatively low density, a relatively low electrical conductivity, and a relatively high porosity, the second zone 902 may have an intermediate density, an intermediate electrical conductivity, and an intermediate porosity, and the third zone 903 may have a relatively high density, a relatively high electrical conductivity, and a relatively low porosity. In some respects, the first zone 901 may have a density of carbon material between approximately 1.5 g / cc and 5.0 g / cc, the second zone 902 may have a density of carbon material between approximately 0.5 g / cc and 3.0 g / cc, and the third zone 903 may have a density of carbon material of less than about 1.5 g / cc. In other aspects, the first zone 901 may include pores having a width of less than about 40 nm, the second zone 902 may include pores having a width of less than about 35 nm, and the third zone 903 may include pores having a width of less than about 30 nm.

[0091] In some other implementations, the second zone 902 may not be defined for the tri-zone particle 900A. In one implementation, the first zone 901 may have a principal dimension Di of less than about 100 nm, the second zone 902 may have a principal dimension D2 between approximately 20 nm and 150 nm, and the third zone 503 may have a principal dimension D3 of approximately 200 nm.

[0092] In some aspects, the pores may decrease in size and volume from one zone to the other. In some implementations, the tri-zone particle may consist entirely of one zone with a range of pore sizes and pores distributions (e.g., pore density). For the example of Figure 9A, the pores 911 associated with the first zone 901 or the first porosity region have relatively large widths and may be defined as macropores, the pores 912 associated with the second zone 902 or the second porosity region have intermediate- sized widths and may be defined as mesopores, and the pores 913 associated with the third zone 903 or the third porosity region have relatively small widths and may be defined as micropores.

[0093] A group of tri-zone porous carbon primary nanoparticles 900A may be joined together to form an aggregate (not shown for simplicity), and a group of the aggregates may be joined together to form an agglomerate (not shown for simplicity). In some implementations, a plurality of mesopores may be interspersed throughout the aggregates formed by respective groups of the carbon nanoparticles. In some aspects, the first porosity region (also referred to as first zone) 901 may be at least partially encapsulated by the second porosity region (also referred to as second zone) 902 such that a respective aggregate mayinclude one or more mesopores and one or more macropores. In one implementation, each mesopore may have a principal dimension between about 3.3 nanometers (nm) and about 19 nm, and each macropore may have a principal dimension between about 0.1 pm and about 1,000 pm. In some instances, the tri-zone particle 900A may include carbon fragments intertwined with each other and separated from one another by at least some of the mesopores.

[0094] In some implementations, the tri-zone particle 900A may have a surface area of exposed carbon surfaces in an approximate range between 10 m2 / g to 3,000 m2 / g and / or a composite surface area (including other substances such as PEgMA micro-confined within pores) in an approximate range between 10 m2 / g to 3,000 m2 / g. In one implementation, an example 3D graphene may include a multitude of tri-zone particles 900A may have an electrical conductivity in an approximate range between 100 S / m to 20,000 S / m at a pressure of 12,000 pounds per square in (psi). In some aspects, 3D graphene may have a specific surface area (“SSA”) of at least approximately 60 m2 / g.

[0095] Figure 9B shows an example step function 900B representative of a tri-zone porous carbon primary nanoparticle of Figure 9 A, according to some implementations. As previously discussed, the pores distributed throughout the tri-zone particle 900A may have different sizes, volumes, or distributions. In some implementations, the average pore volume may decrease based on a distance between a center of the tri-zone particle 900A and an adjacent zone, for example, such that pores associated with the first zone 901 or the first porosity region have a relatively large volume or pore size, pores associated with the second zone 902 or the second porosity region have an intermediate volume, and pores associated with the third zone 903 or the third porosity region have a relatively small volume. The interior region has a higher pore volume than the regions near the periphery. In the example of Figure 9A, the average pore volume in the inner region (also referred to as first zone) is approximately 3 cc / g, the average pore volume in the outermost region (also referred to as third zone) is approximately 0.5 cc / g and the average pore volume in the intermediate region (also referred to as second zone) is between about 0.5 cc / and about 3 cc / g.

[0096] Figure 10 shows a graph 1000 illustrating an example pore volume distribution versus pore size of an example porous carbon primary nanoparticle, according to some implementations. As shown in graph 1000, pores associated with a relatively high pore volume may have a relatively low pore size, for example, such that the pore size generally increases as the pore volume decreases. In some aspects, pores having a pore size less than approximately 1.0 nm may be referred to as micropores, pores having a pore size betweenapproximately 3 and 11 nm may be referred to as mesopores, and pores having a pore size greater than approximately 24 nm may be referred to as macropores.

[0097] Figure 11 A shows a show TEM micrograph 1100A of example porous carbon agglomerates of porous carbon primary nanoparticles in 3D graphene, according to some implementations. In some implementations, each of the carbon structures 1102 may have a substantially hollow core region surrounded by various monolithic carbon growths and / or layering. In some aspects, the monolithic carbon growths and / or layering may be examples of the various carbon structures, growths and / or layering. In some instances, the carbon structures 1102 may include several concentric multi-layered fullerenes and / or similarly shaped carbon structures organized at varying levels of density and / or concentration. For example, the actual final shape, size, and graphene configuration of each of the carbon structures 1102 may depend on various manufacturing processes. The carbon structures 1102 may, in some aspects, demonstrate poor water solubility. As such, in some implementations, non-covalent functionalization may be utilized to alter one or more dispersibility properties of the carbon structures 1102 without affecting the intrinsic properties of the underlying carbon nanomaterial.

[0098] In some aspects, the underlying carbon nanomaterial may include a sp2hybridized carbon nanomaterial including 3D graphene. In some implementations, each of the carbon structures 1102 may have a diameter between approximately 20 and 500 nm. In various implementations, groups of the carbon structures 1102 may coalesce and / or join together to form the aggregates 1104. In addition, groups of the aggregates 1104 may coalesce and / or join together to form the agglomerates 1106. In some aspects, one or more of the carbon structures 1102, the aggregates 1104, and / or the agglomerates 1106 may be used to form one or more of the carbon particles in 3D graphene described herein.

[0099] Figure 1 IB shows another TEM micrograph 1100B of porous carbon agglomerates of porous carbon primary nanoparticles in 3D graphene, according to some implementations. In one implementation, exterior carbon shell-type structures 1152 may fuse together with carbons provided by other carbon shell-type structures 1154 to form a carbon structure 1156. A group of the carbon structures 1156 may coalesce and / or join with one another to form the aggregate 1160. In some aspects, a core region 1158 of each of the carbon structures 1156 may be tunable, for example, in that the col Ire region 1158 may include various defined concentration levels of interconnected graphene structures and / or carbon particles. In some implementations, some of the carbon structures 1156 may have afirst concentration of interconnected carbons approximately between 0.1 g / cc and 2.3 g / cc at or near the exterior carbon shell-type structure 1152.

[0100] In some implementations, the pores in each of the carbon structures 756 may have a width or dimension of less than about 0.5 nm, less than about 0.1 nm, less than about 6.0 nm, or less than about 35 nm. Each carbon structure 756 may also have a second concentration at or near the core region 758 that is different than the first concentration. For example, the second concentration may include several relatively lower-density carbon regions arranged concentrically. In one implementation, the second concentration may be lower than the first concentration at between approximately 0.0 g / cc and 1.0 g / cc or between approximately 1.0 g / cc and 1.5 g / cc.

[0101] In some implementations, graphene nanoplatelets (e.g., formative structures included in each of the carbon structures 756) may include multiple instances of graphene, such as a first graphene layer, a second graphene layer, and a third graphene layer, all stacked on top of each other in a vertical direction. Each of the graphene nanoplatelets (“GNP”) may have a thickness between 1 nm and 3 nm and may have lateral dimensions ranging from approximately 100 nm to 100 pm.

[0102] Figure 12 shows a graph 1200 depicting cumulative pore volume versus pore size of micropores and mesopores dispersed throughout the porous carbon primary nanoparticles particles, according to some implementations. As used herein, “Carbon 1” refers to nanoparticles including mostly micropores (such as less than 5 nm in principal dimension), and “Carbon 2” refers to nanoparticles including mostly mesopores (such as between approximately 20 nm to 50 nm in principal dimension).

[0103] In some implementations, an example 3D graphene may include a plurality of porous carbon agglomerates including one or more non-tri-zone porous carbon primary nanoparticles and / or tri-zone porous carbon primary nanoparticles. Additional details are provided below with reference to Figure 13A. In some instances, each tri-zone nanoparticle may be formed of carbon fragments intertwined with each other and separated from one another by mesopores. A deformable perimeter may form upon coalescence with one or more adjacent non-tri-zone nanoparticles and / or tri-zone nanoparticles.

[0104] Figure 13A shows an example configuration 1300A of example porous carbon agglomerates depicted in Figure 3, according to some implementations. In some implementations, configuration 1300A may be one example of one or more agglomerates of the carbon particles, as previously described in this disclosure. In one implementation, configuration 1300A includes a first porous carbon region 1310 and a second porous carbonregion 1320 positioned adjacent to the first porous carbon region 1310. The first porous carbon region 1310 may be formed of a first concentration level of carbon materials, and the second porous carbon region 1320 formed of a second concentration level of carbon materials dissimilar to the first concentration level of carbon materials. For example, the second porous carbon region 1320 may have a lower concentration level of carbon materials than the first porous carbon region 1310 as shown in Figure 13A. In some aspects, additional porous carbon regions (not shown in Figure 13A for simplicity) may be coupled with at least the second porous carbon region 1320.

[0105] In one implementation, the first porous carbon region 1310 may include first non- tri-zone particles 1311. The configuration of the first non-tri-zone particles 1311 within the first porous carbon region is one example configuration. Other placements, orientations, alignments and / or the like are possible for the non-tri-zone particles. In some aspects, each non-tri-zone particle may be an example of one or more carbon materials disclosed elsewhere in the present disclosure. The first porous carbon region 1310 may also include first tri-zone particles 1312 interspersed throughout the first non-tri-zone particles 911 as shown in Figure 13 A, or positioned in any other placement, orientation, or configuration. Each first tri-zone particle 1312 may be one example of the tri-zone particle 900A of Figure 9A. In addition, or in the alternative, each first tri-zone-particle 1312 may include first carbon fragments 1313 intertwined with each other and separated from one another by mesopores 1314. Each tri- zone-particle may have a first deformable perimeter 1315 configured to coalesce with adjacent first non-tri-zone particles 1311 and / or first tri-zone particles 1312.

[0106] The first porous carbon region 1310 may also include first aggregates 1316, where each aggregate includes a multitude of the first tri-zone particles 912 joined together. In one or more particular examples, each first aggregate may have a principal dimension in a range between 10 nanometers (nm) and 10 micrometers (pm). The mesopores 1314 may be interspersed throughout the first plurality of aggregates, where each mesopore may have a principal dimension between about 3.3 nanometers (nm) and about 19 nm. In addition, the first porous carbon region 1310 may include first agglomerates 1317, where each agglomerate includes a multitude of the first aggregates 1316 joined to each other. In some aspects, each first agglomerate 1317 may have a principal dimension in an approximate range between about 0.1 pm and about 1,000 pm. Macropores 1318 may be interspersed throughout the first aggregates 1316, where each macropore may have a principal dimension between 0.1 pm and 1,000 pm.

[0107] The second porous carbon may include second non-tri-zone particles 1321, which may be one example of the first non-tri-zone particles 1311. The second porous carbon region 1320 may include second tri-zone particles 1322, which may each be one example of each of the first tri-zone particles 1312 and / or may be one example of the tri-zone particle 900A of Figure 9A. In addition, or the alternative, each second tri-zone particle 1322 may include second carbon fragments 1323 intertwined with each other and separated from one another by the mesopores 1314. Each second tri-zone particle 1322 may have a second deformable perimeter 1325 configured to coalesce with one or more adjacent second non-tri- zone particles 1321 or second tri-zone particles 1322.

[0108] In addition, the second porous carbon region 1320 may include second aggregates 1326, where each second aggregate 1326 may include a multitude of the second tri-zone particles 1322 joined together. In one or more particular examples, each second aggregate 1326 may have a principal dimension in a range between 10 nanometers (nm) and 10 micrometers (pm). The mesopores 1314 may be interspersed throughout the second aggregates 1326, each mesopore may have a principal dimension between about 3 nanometers (nm) and about 19 nm. Further, the second porous carbon region 1320 may include second agglomerates 1327, each second agglomerate 1327 may include a multitude of the second aggregates 1326 joined to each other, where each agglomerate may have a principal dimension in an approximate range between 0.1 pm and 1,000 pm. The macropores 1318 may be interspersed throughout the second plurality of aggregates, where each macropore having a principal dimension between 0.1 pm and 1,000 pm.

[0109] In one or more particular examples, the first porous carbon region 1310 may have an electrical conductivity in an approximate range between 500 S / m to 20,000 S / m at a pressure of 12,000 pounds per square in (psi). The second porous carbon region 1320 may have an electrical conductivity in an approximate range between 0 S / m to 500 S / m at a pressure of 12,000 pounds per square in (psi). The first agglomerates 1317 and / or second agglomerates 1327 may include aggregates connected to each other with one or more polymer-based binders.

[0110] In some aspects, each first tri-zone particle 1312 may have a first porosity region (not shown in Figure 13A for simplicity) located around a center of the first tri-zone particle 1312. Similarly, each second tri-zone particle 1322 may have a first porosity region (not shown in Figure 13A for simplicity) located around a center of the second tri-zone particle 1322. The first porosity region may include first pores. A second porosity region (not shown in Figure 13A for simplicity) may surround the first porosity region. The second porosityregion may include second pores. In one implementation, the first pores may define a first pore density, and the second pores may define a second pore density that is different from the first pore density.

[0111] In some aspects, the mesopores 1314 may be grouped into first mesopores and second mesopores (both not shown in Figure 13A for simplicity). In one or more particular examples, the first mesopores may have a first mesopore density, and the second mesopores may have a second mesopore density that is different than the first mesopore density. In addition, the macropores 1318 may be grouped into first macropores that may have a first pore density, and second macropores (both not shown in Figure 13A for simplicity) that may have a second pore density different than the first pore density.

[0112] As previously described herein, 3D graphene including porous carbon agglomerates of porous carbon primary nanoparticles may be produced using high throughput, low-cost, processing of a hydrocarbon gas such as natural gas in an atmospheric microwave plasma reactor. In some implementations, operating parameters associated with an example microwave plasma reactor may be tuned to generate porous 3D graphene including porous carbon agglomerates that include a plurality of carbon flakes (hereinafter referred to as “flaky carbons”).

[0113] In some other implementations, 3D graphene including flaky carbons may be surface functionalized using hexamethyldisiloxane (“HMDSO”) to produce silicon containing functional groups dispersed in, or chemical bound to, the surface of flaky carbons. Example silicon containing functional groups may include silanol functional groups (Si-O-H). Figures 13B-13C show scanning electron microscopy (“SEM”) micrographs 1300B-1300C of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons, according to some implementations. As can be seen, the porous carbon agglomerates may be characterized by amorphous flaky carbons 1350 (also referred to herein as flaky carbon layers) including mesopores 1351, and a plurality of graphene flakes 1353, and may be disposed as one or more graphene layers (not shown for simplicity). Graphene flakes 1353 may be characterized by a flat and / or edgy morphology. In some implementations, the number of graphene layers in 3D graphene including flaky carbons may be between about 5 and 15. In some implementations, the number of graphene layers in 3D graphene including flaky carbons may be between about 10 and 15.

[0114] Figure 13D shows a transmission electron microscopy (“TEM”) micrograph 13000 of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons, according to some implementations. As previously described with reference toFigure 2, 3D graphene including flaky carbons may also be characterized as wavy and / or wrinkled graphene. In some aspects, at least some graphene layers of the wavy and / or wrinkled graphene produced by microwave processing of hydrocarbons may adjoin together to define various ridges and valleys 1352. At least some of the ridges and valleys 1352 may produce areas of increased flexibility, which may enable infiltration by, for example, a polymeric compatibilizer including polypropylene-graft-maleic anhydride (“PPgMA”).

[0115] Figure 13E shows a scanning transmission electron microscopy (“STEM”) micrograph 1300E of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons 1350, according to some implementations. Figure 13F shows an electron energy loss spectroscopy (“TEM-EELS”) micrograph HOOF of 3D graphene including silicon-doped porous carbon agglomerates including flaky carbons 1350, according to some implementations. As shown in micrograph 1300E, 3D graphene including flaky carbons 1350 may include one or more graphene flakes 1354 that may include few layers of graphene, and one or more graphene flakes 1354’ that may include multiple layers of graphene. As can be seen in micrograph 1300E, graphene flake 1354 may be characterized by a wavy or wrinkled morphology, as previously described herein. Graphene flakes 1354 or 1354’ may include carbon regions 1355, which are represented as bright areas in micrograph 1300E, and as red regions in micrograph HOOF. Additionally, silicon present as siliconoxide functional groups or particles (“SiOx”) 1356 or silanol groups disposed on carbon are represented as relatively darker areas in micrograph 1300E. As can be seen in micrograph HOOF, TEM-EELS analysis confirmed the presence of silicon as silicon-oxide functional groups or particles (“SiOx”) 1356 disposed on carbon surfaces, where the SiOx particles1356 are shown as green areas. Additionally, as can be seen in micrograph HOOF, TEM- EELS analysis also confirmed the presence of oxygen containing surface functional groups1357 disposed on carbon surfaces, where the functional groups including oxygen bound to carbon surfaces are shown as blue dots.

[0116] Without being bound by any particular theory, the example silanol functional groups disposed on 3D graphene including flaky carbons may enhance condensation reactions with glass fibers under high heat processing conditions, for example, temperatures greater than 180 °C, associated with the production of GFRP composites. Additionally, the silanol functional groups may also participate in ring-opening of maleic anhydride in PPgMA to form covalent bonds. These covalent bonding reactions may promote the compatibilization of 3D graphene in the GFRP composite matrix and increase the dispersionof 3D graphene in the GFRP composite matrix yielding a lightweight GFRP composite with superior mechanical properties.

[0117] In some implementations, the silicon content in 3D graphene including flaky carbons surface functionalized with silanol functional groups may be between approximately 5 at% and approximately 10 at%. In some implementations, the silicon content in 3D graphene including flaky carbons surface functionalized with silanol functional groups may be between approximately 5 at% and approximately 8 at%.

[0118] In some implementations, the oxygen content in 3D graphene including flaky carbons surface functionalized with silanol functional groups may be between approximately 2 at% and approximately 8 at%. In some implementations, the oxygen content in 3D graphene including flaky carbons surface functionalized with silanol functional groups may be between approximately 3 at% and approximately 6 at%. The atomic concentration of the surface functional groups disposed on 3D graphene may be measured using energy dispersive X-ray spectroscopy (“EDS’), X-ray fluorescence (“XRF”), or other analytical techniques. In some instances, surface oxygen may be present predominantly as C=O covalent double bonds groups as opposed to C-0 covalent groups in the 3D graphene including flaky carbons surface functionalized with silanol functional groups. In some instances, the atomic ratio of oxygen in C=O groups to oxygen in C-0 groups, measured using the Is line intensities for oxygen during EDS analysis of the 3D graphene including flaky carbons surface functionalized with silanol functional groups, may be between 5 and 6.

[0119] In some implementations, the BET surface area (measured using nitrogen gas) of 3D graphene including flaky carbons surface functionalized with silanol functional groups may be between approximately 100 m2 / g and approximately 200 m2 / g. In some implementations, the BET surface area (measured using nitrogen gas) of 3D graphene including flaky carbons surface functionalized with silanol functional groups may be between approximately 100 m2 / g and approximately 150 m2 / g.Carbon Reinforced Polymer Composites including 3D Graphene

[0120] In various implementations, carbon reinforced polymer composites may include a polymer matrix or blend including one or more polymers, polyethylene-graft-maleic anhydride (“PEgMA”) compatibilizer, and 3D graphene. 3D graphene may include any one of the 3D graphene implementations previously disclosed in this disclosure. In some implementations, an example carbon reinforced polymer composite may further include anantioxidant additive. In some implementations, the polymer matrix may include a first polymer including a high-flexural modulus polymer, for example, high density polyethylene (“HDPE”), to increase stiffness, and a second polymer including a low-flexural modulus plastomer. In general, a plastomer is a polymer material which combines the properties of elastomers and plastics to balance rubber-like elasticity with the processing capabilities, of impact resistance or toughness of plastics. In some instances, an example plastomer may include an alpha-olefin copolymer. In some other instances, an example alpha-olefin may include octene copolymer linear low-density polyethylene (“LLDPE”).

[0121] In some implementations, example antioxidants may include one or more of free radical scavengers or peroxide scavengers. In some instances, free radical scavengers may include one or more of sterically hindered phenols or secondary aromatic amines. In some instances, peroxide scavengers may include one or more of bivalent phosphorus compounds (also known as phosphites) or thioethers.

[0122] In some instances, carbon reinforced polymer composites may include a polymer blend including a first polymer characterized by a first flexural modulus, and a second polymer characterized by a second flexural modulus that is different from the first flexural modulus, PEgMA, and 3D graphene. In some implementations, the example composite material may be characterized by a flexural modulus that is greater than the flexural modulus of the first polymer by at least 10%.

[0123] In some implementations, carbon reinforced polymer composites may include a polymer blend including one or more polymers, each characterized by a flexural modulus that is different from each of the other polymers in the blend, PEgMA, and 3D graphene. In some implementations, the composite material may be characterized by a flexural modulus that is greater than the flexural modulus of the first polymer by at least 10%.

[0124] In some implementations, at least some carbon atoms in 3D graphene may be oxidized with one or more oxy gen-containing groups. Without being bound by any particular theory, oxidizing carbon atoms may increase carbon-PEgMA molecule chemical bonding and help to increase the strength of the composite material.

[0125] In some instances, the polymer matrix or blend in the example composite materials may include a combination of a thermoplastic resins and maleated copolymers, maleic copolymers, and / or maleated polymers. In some aspects, the thermoplastic resin may include LLDPE resin including an ethylene-butene copolymer and / or alpha-olefins. In some other aspects, the thermoplastic resin may include any type of polyethylene-based polymers, including LLDPE, linear polyethylene (“LPE”), metallocene polyethylene (“mPE”), high-density polyethylene (“HDPE”), ultra-high molecular weight polyethylene (“UHMWPE”), nylons, polypropylene, or polyether ether ketone (“PEEK”), or similar polymers. Thermoplastic resins may also include any type of semi-crystalline and amorphous thermoplastic materials.

[0126] In some implementations, a first polymer in an example carbon reinforced polymer composite may include LLDPE, and a second polymer may include an alpha-olefin copolymer. Figure 14 shows a graph 1400 which provides a comparison of the flexural modulus of LLDPE with that of several example carbon reinforced polymer composites, according to some implementations. The example carbon reinforced polymer composites may include a polymer blend, PEgMA, and 3D graphene. The polymer blend may include LLDPE and an alpha-olefin copolymer. As shown in Figure 14, the example carbon reinforced polymer composites may be characterized by a flexural modulus that is greater than the flexural modulus of LLDPE by between about 10% and about 60%. Additionally, the example carbon reinforced polymer composites may be characterized by a flexural modulus of between about 80,000 psi and about 130,000 psi. The flexural modulus of the example may be measured at a temperature of 23°C under ASTM D.790 at a 1% secant modulus value.

[0127] Figure 15 shows a graph 1500 which provides a comparison of the tensile strength and elongation at break of LLDPE with that of several example carbon reinforced polymer composites, according to some implementations. As shown in Figure 14, the example carbon reinforced polymer composites may be characterized by a tensile strength of between about 3000 psi and about 4500 psi. Additionally, the example carbon reinforced polymer composites may be characterized by an elongation at break of between about 800% and about 1400%. The example carbon reinforced polymer composites may include a polymer blend, PEgMA, and 3D graphene.

[0128] In some implementations, any one of the example carbon reinforced polymer composites as previously described may include an antioxidant additive. In some aspects, example antioxidant additives may include one or more of sterically hindered phenols, secondary aromatic amines, phosphites, thioethers, or combination thereof.Thermoplastic Polyolefins Composites

[0129] As previously described, there is a need for lightweighting thermoplastic polyolefins (“TPO”) composites using novel filler materials that result in a TPO composite density of less than about 0.95 g / cc.

[0130] In some implementations, a thermoplastic polyolefin (“TPO”) composite may include a polypropylene homopolymer, a polypropylene copolymer and an elastomer. In some aspects, an increase in the density of an example TPO composite as measured under ASTM D.792 may be less than about 5% relative to the nominal density of the polypropylene homopolymer. In some implementations, an example TPO composite may further include a carbon material including one or more of graphite, amorphous carbon, fullerene, carbon nanotubes, single layer graphene (“SLG”), few layer graphene (“FLG”), three-dimensional (“3D”) graphene, or many layer graphene (“MLG”). In some implementations, a loading of the carbon material in the TPO composite may be less than or equal to about 0.5 wt%.

[0131] In some implementations, any one of the previously described 3D graphene materials may be used as filler materials in TPO composites. In some implementations, an example carbon reinforced TPO composite may include a polypropylene homopolymer, a polypropylene copolymer, an elastomer, and 3D graphene. In some implementations, an increase in the density of the TPO composite including 3D graphene as measured under ASTM D.792 may be less than about 5% relative to the nominal density of the polypropylene homopolymer. The nominal density of polypropylene homopolymer may be about 0.90 g / cc. In some implementations, ethylene propylene diene terpolymer (“EPDM”) may replace the polypropylene copolymer and the elastomer during formulating the example TPO composites including 3D graphene.

[0132] In some implementations, polypropylene homopolymers may include atactic polypropylene, isotactic polypropylene, syndiotactic polypropylene, or any other structural variations thereof. In some implementations, the polypropylene copolymers are produced by polymerizing ethene and propene and may include one or more of polypropylene impact copolymers, polypropylene random copolymers, or polypropylene graft copolymers. The chain structures of these polypropylene homopolymers and copolymers are well known in the art, and therefore are not described herein so as to not obscure description of various aspects of the subject matter disclosed herein.

[0133] In some implementations, the amount (also referred to as loading in this disclosure) of the polypropylene homopolymer in an example carbon reinforced TPO composite including 3D graphene may be between about 60 wt% and about 80 wt%. In someimplementations, the amount of the polypropylene copolymer in an example carbon reinforced TPO composite including 3D graphene may be between about 10 wt% and about 25 wt%.

[0134] In some implementations, an example carbon reinforced TPO composite including 3D graphene may be characterized by a decrease in the flexural modulus of the TPO composite as measured under ASTM D.790 at a 1% secant module value relative to the flexural modulus of the polypropylene homopolymer. In some aspects, the decrease in the flexural modulus of the carbon reinforced TPO composite including 3D graphene may be less than about 35% relative to the nominal flexural modulus of the polypropylene homopolymer. In some aspects, the decrease in the flexural modulus of the carbon reinforced TPO composite including 3D graphene may be less than about 5% relative to the nominal flexural modulus of the polypropylene homopolymer. For reference purposes, the nominal flexural modulus of polypropylene homopolymer may be between about 215,000 psi (or about 1484 MPa) and about 280,000 psi (or about 1932 MPa).

[0135] In other implementations, an example carbon reinforced TPO composite including 3D graphene may be characterized by a decrease in the ultimate tensile strength of the TPO composite including 3D graphene as measured under ASTM D.638 relative to the nominal ultimate tensile strength of the polypropylene homopolymer. In some aspects, the decrease in the ultimate tensile strength of the carbon reinforced TPO composite including 3D graphene may be less than about 35% relative to ultimate tensile strength of the polypropylene homopolymer. In some aspects, the decrease in the ultimate tensile strength of the carbon reinforced TPO composite including 3D graphene may be less than about 20% relative to ultimate tensile strength of the polypropylene homopolymer. For reference purposes, the nominal ultimate tensile strength of polypropylene homopolymer may be between about 5,400 psi (or about 37 MPa) and about 5,700 psi (or about 39 MPa).

[0136] In some other implementations, an example carbon reinforced TPO composite including 3D graphene may be characterized by one or more of an increase in a density of the TPO composite including 3D graphene as measured under ASTM D.792 of less than about 5% relative to the nominal density of the polypropylene homopolymer, a decrease in an ultimate tensile strength of the TPO composite including 3D graphene as measured under ASTM D.638 of less than about 35% relative to a nominal ultimate tensile strength of the polypropylene homopolymer, or a decrease in an ultimate tensile strength of the TPOcomposite including 3D graphene as measured under ASTM D.638 of less than about 35% relative to a nominal ultimate tensile strength of the polypropylene homopolymer.

[0137] In some implementations, a carbon reinforced TPO composite may include 3D graphene in an amount that is less than or equal to about 0.5 wt%. In some other implementations, a carbon reinforced TPO composite may include 3D graphene in an amount that is less than or equal to about 1 wt%. In some aspects, the carbon reinforced TPO composite including 3D graphene may not include a polypropylene-graft-maleic anhydride (PP-g-MA) compatibilizer commonly used in propylene based TPO composites.

[0138] In some implementations, an elastomer in a carbon reinforced TPO composite including 3D graphene may include an ethylene octene block copolymer. In some aspects, a carbon reinforced TPO composite including 3D graphene may include an elastomer in an amount that is between about 10 wt% and about 15 wt%.

[0139] In some implementations, a carbon reinforced TPO composite including 3D graphene may further include an effective amount of an alpha-nucleating agent to increase the rate of polypropylene crystallization. In other implementations, a carbon reinforced TPO composite including 3D graphene may further include less than about 1 wt% of an alphanucleating agent. In some aspects, example alpha- nucleating agents may include one or more of talc, sodium benzoate, organic phosphate esters, or derivates of sorbitol. In other aspects, derivatives of sorbitol may include one or more of 1,2,3,4-bis- dibenzylidene sorbitol (“DBS”), l,2,3,4-bis-( p-methoxybenzylidene sorbitol) (“DOS”), l,2,3,4-bis-(p- methylbenzylidene sorbitol) (“MBDS”), l,2,3,4-bis-(3,4-dimethylbenzylidene sorbitol), l,3:2,4-di(3,4- dimethylbenzylidene) sorbitol (“DMDBS”), or l,3:2,4-bis-o-(3,4- dimethylbenzylidene)-d-sorbitol.

[0140] In some implementations, a carbon reinforced TPO composite including 3D graphene may include between about 60 wt% and about 80 wt% polypropylene homopolymer, between about 10 wt% and about 15 wt% polypropylene impact copolymer, between about 10 wt% and about 15 wt% ethylene octene block copolymer, less than about 1 wt% an alpha-nucleating agent, and less than or equal to about 0.5 wt% 3D graphene. Increasing the 3D graphene content in the example TPO composites previously herein to above 0.5 wt% may increase the raw material costs of the TPO composites without resulting in a significant improvement in mechanical properties or reduction in the density of the TPO composite.

[0141] In some implementations, the flexural modulus of a TPO composite including 3D graphene as measured under ASTM D.790 at a 1% secant modulus value may be between about 187,000 psi (or about 1290 MPa) and about 208,000 psi (or about 1435 MPa).

[0142] In some implementations, the percentage elongation at break of a TPO composite including 3D graphene as measured under ASTM D.638 may be between about 875% and about 1150%.

[0143] In some implementations, the ultimate tensile strength of a TPO composite including 3D graphene as measured under ASTM D.638 may be between about 3960 psi (or about 27 MPa) and about 4450 psi (or about 31 MPa).

[0144] In some implementations, the impact strength (also referred to as notched Izod impact strength) of a TPO composite including 3D graphene as measured under ISO 180 / 1 A at 23 °C may be between about 20 kJ / m2(or about 11 ft-lbs / in2) and about 40 kJ / m2(or about 19 ft-lbs / in2).

[0145] In some implementations, the density of a TPO composite including 3D graphene as measured under ASTM D.792 may be less than about 0.95 g / cc. In some implementations, the density of a TPO composite including 3D graphene as measured under ASTM D.792 may be about 0.92 g / cc.

[0146] In some implementations, an example 3D graphene included in any one of the carbon reinforced TPO composites previously described herein may include porous carbon agglomerates of porous carbon primary nanoparticles 100A (referring to Figure 1A) including one or more interconnected bundles 182 of electrically conductive graphene layers. In some aspects, each graphene layer may 186 be characterized by a linear dimension of between approximately 50 nm and 200 nm. In other aspects, the graphene layers 186 may include one or more of single layer graphene (SLG), few layer graphene (FLG), or many layer graphene (MLG). In some other aspects, the graphene layers 186 may be arranged as one or more stacks 183 connected to each other and defining a 3D porous scaffold structure 181 including mesopores. In some instances, the one or more stacks 183 may be disposed substantially orthogonal to each other. In some instances, the example porous carbon agglomerates may be characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi).

[0147] In some implementations, another example 3D graphene included in any one of the carbon reinforced TPO composites may include porous carbon agglomerates of porous carbon primary nanoparticles 805 (referring to Figures 8A-8D, and Figure 9A). In someimplementations, the example porous carbon primary nanoparticles may include an inner porous shell 813 disposed about a center 816 of the respective porous carbon primary nanoparticle and enclosing an inner porous carbon region 811, an outer porous shell 810 enclosing an outer porous carbon region 812 disposed between the inner porous shell and the outer porous shell and an interconnected porous network disposed in and in fluid communication with the inner and outer porous carbon regions. In some implementations, the inner porous carbon region 811 and the outer porous carbon region 812 may be characterized by an average pore size and an average pore density associated with each region. In some implementations, the average pore size may decrease along a radial direction from the center to the outer porous shell (for example, referring to Figure 9B). In some other implementations, the porous carbon agglomerates of porous carbon primary nanoparticles may further include one or more intermediate porous shells (referring to Figure 9A) disposed between the inner porous shell and the outer porous shell. In some instances, each of the intermediate porous shells encloses a respective intermediate porous carbon region.

[0148] In some implementations, the example porous carbon agglomerates may be characterized by a Raman spectroscopy signature having an ID / IG ratio between approximately 0.95 and 1.05. In other implementations, the porous carbon agglomerates are characterized by a Brunauer-Emmett-Teller (“BET”) surface area between approximately 50 m2 / g and 300 m2 / g measured using nitrogen gas. In some implementations, the porous carbon agglomerates including one or more porous carbon regions as previously described may be characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi).EXAMPLESEXAMPLE 1, Mechanical properties of example TPO composite test samples.

[0149] Screening of TPO composite test samples were conducted as listed in Table 1 below. The flexural modulus (“FM”) of the TPO composite test samples including 3D graphene was measured under ASTM D.790 at a 1% secant modulus value. The percentage elongation at break (“%Elongation”) of the TPO composite samples were measured under ASTM D.638. The ultimate tensile strength (“UTS”) of the TPO composite test samples were measured under ASTM D.638. The impact strength (“IS”), also referred to as notched Izod impact strength, of the TPO composites test samples was measured under ISO 180 / 1 A at 23 °C. About 1 wt% of a derivative of sorbitol, l,3:2,4-bis-o-(3,4-dimethylbenzylidene)-d- sorbitol, was used as an alpha-nucleating agent during formulation of the TPO composite testsamples. Polypropylene-graft-maleic anhydride (PPgMA, also denoted as PP-g-MA) was not used during formulating the TPO composite test samples.Table 1. Mechanical properties of example TPO composite test samples.

[0150] In Table 1, “neat polypropylene resins” refers to the polypropylene homopolymer resins used in these formulations. The nominal density of the polypropylene homopolymer as measured under ASTM D.792 was about 0.90 g / cc. The melt flow rate, 230°C / 2160g, measured under ASTM D.1238 was between about 7.5 g / 10 min and about 20 g / 10 min. The other nominal mechanical properties of polypropylene homopolymer resins are listed in Table 1.

[0151] The polypropylene impact copolymer (“PP Impact copolymer”) included a high crystallinity, high impact polypropylene copolymer resin. The density of polypropylene impact copolymer was about 0.90 g / cc. The melt flow rate, 230°C / 2160g, measured under ASTM D.1238 was between about 20 g / 10 min and about 30 g / 10 min. The flexural modulus of the polypropylene impact copolymer measured under ASTM D.790 at a 1% secant modulus value was between about 144,000 psi (or about 994 MPa) and about 175,000 psi (or about 1208 MPa). The percentage elongation at break of the polypropylene impact copolymer measured under ASTM D.638 was between about 5.7% and about 6%. The ultimate tensile strength of the polypropylene impact copolymer was between about 2890 psi (or about 20 MPa) and about 3480 psi (or about 24 MPa). The notched Izod impact strength of the polypropylene impact copolymer measured at 23 °C under ISO 180 / 1A, was about 22 ft.lb / in2(or about 46 kJ / m2).

[0152] The elastomer included an octene block copolymer with a density of between about 0.87 g / cc and about 0.89 g / cc as measured under ASTM D.792. The melt flow rate, 190°C / 2160g, measured under ASTM D.1238 was about 15 g / 10 min. The percentage elongation at break of the octene block copolymer measured under ASTM D.412 was between about 1500% and 1800%. The ultimate tensile strength of octene block copolymer was between about 1000 psi (or about 7 MPa) and about 1100 psi (or about 7.6 MPa).

[0153] In the example TPO composite test samples shown in Table 1, the 3D graphene content (“%XT”) was about 0.5 wt%. Structural details and properties related to 3D graphene were previously disclosed herein. Additional details related to a comparison between 3D graphene used in formulating the TPO composite test samples shown in Table 1 and commercially available graphene are provided in Example 2 below.

[0154] The density of the TPO composite test samples was found to be about 0.92 g / cc under ASTM D.792. Accordingly, lightweighting of TPO composites may be realized without sacrificing mechanical properties including flexural modulus and ultimate tensile strength required for the fabrication of several polypropylene based end products.EXAMPLE 2, Comparison of example 3D graphene with commercially available graphene.

[0155] Figure 16A shows a scanning electron microscopy (“SEM”) micrograph 1600A of porous carbon agglomerates of porous carbon primary nanoparticles including 3D graphene, according to some implementations. Details related to the porous carbon agglomeratesincluding 3D graphene were previously described with reference to Figures 1A-1C, Figure2, Figure 3, and Figures 13B-13D and excerpts are reproduced here for convenience.

[0156] The nanoparticles 100A (with reference to Figure 1A) may include one or more interconnected bundles 182 of electrically conductive graphene layers include or packed in the porous carbon nanoparticles that make up the porous carbon agglomerates. The graphene layers 186 may include one or more of single layer graphene (SLG), few layer graphene (FLG), or many layer graphene (MLG) and may be characterized by a linear dimension of between about 50 nm and about 200 nm. The graphene layers 186 may be arranged as one or more stacks 183 connected to each other and defining a 3D porous scaffold structure 181 including mesopores. The one or more stacks 183 may be disposed substantially orthogonal to each other.

[0157] The porous carbon agglomerates may be characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi) and a BET surface area of between about 50 m2 / g and about 300 m2 / g. Without being bound by any particular theory, the example porous carbon agglomerates including graphene layers arranged as stacks connected to each other in a 3D porous scaffold structure including mesopores enables reinforcement of the TPO composites previously described herein even at small 3D graphene loadings in the TPO composites.

[0158] As such, TPO composite densities as low as 0.92 g / cc under ASTM D.792 may be achieved using the example 3D graphene as fillers, which supports the lightweighting of TPO composites without sacrificing mechanical properties including flexural modulus and ultimate tensile strength.

[0159] Figure 16B shows a SEM micrograph 1600B of 2-dimensional graphene nanoplatelets. The 2-dimensional nanoplatelets (supplied by XG Sciences, Lansing, MI) is produced from graphite as the starting material. The nanoplatelets or graphene flakes include nanoparticles consisting of short stacks of graphene sheets. The nanoplatelets have an average thickness of approximately 7 nm and a surface area of 120 m2 / g to 150 m2 / g. Average particle size is between 5 pm and 25 pm. As can be seen in micrograph 1600B, the fairly crystalline sheets of graphene nanoplatelets 1603B do not include the mesoporous structure of the carbon agglomerates 1603 A of porous carbon primary nanoparticles including 3D graphene shown in Figure 16A.

[0160] Kiziltas et al. (2001) formulated a TPO composite including 55 wt% - 63 wt% polypropylene, 30 wt% natural rubber, 5 wt% PP-g-MA compatibilizer, and 2 wt% - 10 wt% 2D graphene nanoplatelets (supplied by XG Sciences). The density and the percentage elongation at break of the TPO composites were not reported. The TPO composites were characterized by a tensile strength of less than 20 MPa (2899 psi) and a notched Izod impact strength of less than 10 kJ / m2(about 4.8 ft.lb / in2) at a significantly higher 2D graphene nanoplatelet loading of 2 wt% - 10 wt% compared to the 3D graphene loading described in Example 1. The reported tensile strength and notched Izod impact strength are lower than the ultimate tensile strength and notched Izod impact strength, respectively, of the TPO composites of Example 1. The lower mechanical strength properties in the TPO composite of Example 2 is not desirable. It is well known that high tensile strength is desired for consumer products including luggage because materials with higher tensile strength yield a more durable product that can withstand increased stress and wear and tear before breaking.

[0161] Figure 16C shows a SEM micrograph 1600C of single layer graphene flakes. Single layer graphene powder (supplied by ACS Material LLC, Pasadena, CA) is produced as graphene flakes using a combination of thermal exfoliation reduction and hydrogen reduction. The thickness of the single layer graphene flakes 1603C is between 0.6 nm and 1.2 nm and is characterized by a BET surface area of between 400 m2 / g to 1000 m2 / g. The flake size is between 0.4 pm and 0.5 pm. As can be seen in micrograph 1600C, the fairly crystalline single layer graphene flakes do not include the porous structure of the carbon agglomerates 1603 A of porous carbon primary nanoparticles including 3D graphene shown in Figure 16A.

[0162] As used herein, a phrase referring to “at least one of’ or “one or more of’ a list of items refers to any combination of those items, including single members. For example, “at least one of: a, b, or c” is intended to cover the possibilities of: a only, b only, c only, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a and b and c. Unless otherwise specified in this disclosure, for construing the scope of the term “about” or “approximately,” the error bounds associated with the values (dimensions, operating conditions etc.) disclosed is ± 1% of the values indicated in this disclosure. The error bounds associated with the values disclosed as percentages is ± 1% of the percentages indicated. The word “substantially” used before a specific word includes the meanings “considerable in extent to that which is specified,” and “largely but not wholly that which is specified.”

[0163] The various illustrative components, compositions, and operations, described in connection with the implementations disclosed herein may be implemented including the structures disclosed in this specification, their functionalities, and the structural equivalents thereof, and may be interchangeably used. Whether such functionality is implemented compositions or operations depends upon the application and design constraints imposed on the overall system.

[0164] Various modifications to the implementations described in this disclosure may be readily apparent to persons having ordinary skill in the art, and the generic principles defined herein may be applied to other implementations without departing from the spirit or scope of this disclosure. Thus, the claims are not intended to be limited to the implementations shown herein but are to be accorded the widest scope consistent with this disclosure, the principles and the novel features disclosed herein.

[0165] Additionally, various features that are described in this specification in the context of separate implementations also can be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation also can be implemented in multiple implementations separately or in any suitable subcombination. As such, although features may be described above in combination with one another, and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

[0166] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. Further, the drawings may schematically depict one more example processes in the form of a flowchart or flow diagram. However, other operations that are not depicted can be incorporated in the example processes that are schematically illustrated. For example, one or more additional operations can be performed before, after, simultaneously, or between any of the illustrated operations. In some circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single product or packaged into multiple products.REFERENCESKiziltas, A, Tamrakar, S., Rizzo, J., and Mielewski, D., “Characterization of graphene nanoplatelets reinforced sustainable thermoplastic elastomers,” Composites Part C: Open Access 6 (2021) 100172.

Claims

AMENDED CLAIMS received by the International Bureau on 27 March 2025 (27.03.2025)What is claimed is:

1. A glass fiber reinforced polymer (GFRP) composite including: a polypropylene polymer; glass fibers; polypropylene-graft-maleic anhydride (PPgMA); and three-dimensional (3D) graphene, wherein a ratio of a flexural modulus of the glass fiber reinforced polymer composite to a flexural modulus of the polypropylene polymer is between about 2 and about 3.

2. The GFRP composite of claim 1, wherein the composite includes about 30 wt% glass fibers, about 2 wt% PPgMA, and about 2 wt% 3D graphene dispersed in the polypropylene polymer.

3. The GFRP composite of claim 1, wherein the glass fibers includes surface amine functional groups generated by treating the glass fibers with 3-aminopropyl triethoxysilane (APTES).

4. The GFRP composite of claim 1 , wherein 3D graphene includes surface oxygen functional groups generated by ozone treatment of 3D graphene.

5. The GFRP composite of claim 4, wherein the surface oxygen functional groups include one or more of epoxide (C-O-C), hydroxyl (-OH), ether (C-O-C), ketone (O-C=O), or carboxylic acid (-COOH) groups.

6. The GFRP composite of claim 5, wherein a ratio of the concentration (at%) of oxygen associated with C=O groups to the concentration of oxygen (at%) associated with C- O groups is between approximately 5 and 6.

7. The GFRP composite of claim 1, wherein 3D graphene includes surface silanol (Si-O-H) functional groups.

438. The GFRP composite of claim 7, where a silicon content associated with 3D graphene including surface silanol functional groups is between approximately 5 at% and approximately 10 at%.

9. The GFRP composite of claim 8, wherein an oxygen content associated with 3D graphene including surface silanol functional groups is between approximately 2 at% and approximately 8 at%.

10. The GFRP composite of claim 7, where a BET surface area associated with 3D graphene including surface silanol functional groups is between approximately 100 m2 / g and approximately 150 m2 / g.

11. The GFRP composite of claim 1 , wherein 3D graphene includes porous carbon agglomerates including a plurality of graphene layers.

12. The GFRP composite of claim 11, wherein a number of graphene layers in the plurality of graphene layers is between 10 and 15.

13. The GFRP composite of claim 1, wherein 3D graphene includes porous carbon agglomerates of porous carbon primary nanoparticles, each porous carbon primary nanoparticle including one or more interconnected bundles of electrically conductive graphene layers.

14. The GFRP composite of claim 13, wherein each graphene layer is characterized by a linear dimension of between approximately 50 nm and 200 nm.

15. The GFRP composite of claim 13, wherein the graphene layers include one or more of single layer graphene (SLG), few layer graphene (FLG), or many layer graphene (MLG).

16. The GFRP composite of claim 13, wherein the graphene layers are arranged as one or more stacks connected to each other and defining a 3D porous scaffold structure including mesopores.4417. The GFRP composite of claim 16, wherein the one or more stacks are disposed substantially orthogonal to each other.

18. The GFRP composite of claim 13, wherein the porous carbon agglomerates are characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi).

19. The GFRP composite of claim 1, wherein 3D graphene includes porous carbon agglomerates of porous carbon primary nanoparticles, wherein a respective porous carbon primary nanoparticle includes: an inner porous shell disposed about a center of the respective porous carbon primary nanoparticle and enclosing an inner porous carbon region; an outer porous shell enclosing an outer porous carbon region disposed between the inner porous shell and the outer porous shell; and an interconnected porous network disposed in and in fluid communication with the inner and outer porous carbon regions.

20. The GFRP composite of claim 19, wherein the inner porous carbon region and the outer porous carbon region are characterized by an average pore size and an average pore density associated with each region.

21. The GFRP composite of claim 19, wherein the average pore size decreases along a radial direction from the center of the respective porous carbon primary nanoparticle to the outer porous shell of the respective porous carbon primary nanoparticle.

22. The GFRP composite of claim 19, further including one or more intermediate porous shells disposed between the inner porous shell and the outer porous shell of the respective porous carbon primary nanoparticle, wherein each of the intermediate porous shells encloses a corresponding intermediate porous carbon region.

23. The GFRP composite of claim 19, wherein the porous carbon agglomerates are characterized by a Raman spectroscopy signature having an ID / IG ratio between approximately 0.95 and 1.05.4524. The GFRP composite of claim 19, wherein the porous carbon agglomerates are characterized by a Brunauer-Emmett-Teller (BET) surface area between approximately 50 m2 / g and 300 m2 / g measured using nitrogen gas.

25. The GFRP composite of claim 19, wherein the porous carbon agglomerates are characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi).

26. A glass fiber reinforced polymer (GFRP) composite including: a polypropylene polymer; glass fibers including surface amine functional groups; polypropylene-graft-maleic anhydride (PPgMA); and three-dimensional (3D) graphene including surface oxygen functional groups, wherein a ratio of a flexural modulus of the glass fiber reinforced polymer composite to a flexural modulus of polypropylene polymer is between about 2 and about 3, and wherein the GFRP composite includes about 30 wt% of glass fibers including surface amine functional groups, about 2 wt% PPgMA, and about 2 wt% 3D graphene including surface oxygen functional groups dispersed in the polypropylene polymer.

27. The GFRP composite of claim 26, wherein the flexural modulus of the GFRP composite is about 790,000 psi.

28. The GFRP composite of claim 26, wherein a density of the GFRP composite is about 1.13 g / cc.

29. The GFRP composite of claim 26, wherein the surface oxygen functional groups are generated by ozone treatment of 3D graphene.

30. A carbon reinforced polymer composite including: a polymer blend including a first polymer characterized by a first flexural modulus, and a second polymer characterized by a second flexural modulus that is different from the first flexural modulus; polyethylene-graft-maleic anhydride (PEgMA); andthree-dimensional (3D) graphene, wherein the composite is characterized by a third flexural modulus that is greater than the first flexural modulus by at least 10%.

31. A carbon reinforced polymer composite including: a polymer blend including one or more polymers each characterized by a different flexural modulus; polyethylene-graft-maleic anhydride (PEgMA); and three-dimensional (3D) graphene, wherein the composite is characterized by a composite flexural modulus that is greater than the flexural modulus of each of the one or more polymers in the polymer blend.

32. The carbon reinforced polymer composite of claim 31, wherein the 3D graphene includes porous carbon agglomerates of porous carbon primary nanoparticles, each porous carbon primary nanoparticle including one or more interconnected bundles of electrically conductive graphene layers.

33. The carbon reinforced polymer composite of claim 31, wherein the 3D graphene includes porous carbon agglomerates of porous carbon primary nanoparticles, wherein a respective porous carbon primary nanoparticle includes: an inner porous shell disposed about a center of the respective porous carbon primary nanoparticle and enclosing an inner porous carbon region; an outer porous shell enclosing an outer porous carbon region disposed between the inner porous shell and the outer porous shell; and an interconnected porous network disposed in and in fluid communication with the inner and outer porous carbon regions.

34. The carbon reinforced polymer composite of claim 33, wherein the inner porous carbon region and the outer porous carbon region of the respective porous carbon primary nanoparticle are characterized by an average pore size and an average pore density associated with each region.

35. The carbon reinforced polymer composite of claim 33, wherein the porous carbon agglomerates are characterized by an electrical conductivity of between about 500S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi)-36. The carbon reinforced polymer composite of claim 31 , wherein: a first polymer associated with the one or more polymers includes linear low-density polyethylene (LLDPE); and a second polymer associated with the one or more polymers includes an alpha-olefin copolymer.

37. The carbon reinforced polymer composite of claim 36, wherein a flexural modulus of the composite is greater than the flexural modulus of LLDPE by between about 10% and about 60%.

38. The carbon reinforced polymer composite of claim 36, wherein a flexural modulus of the composite is between about 80,000 psi and about 130,000 psi as measured at a temperature of 23°C under ASTM D.790 at a 1% secant modulus value.

39. The carbon reinforced polymer composite of claim 36, wherein a tensile strength of the composite is between about 3000 psi and about 4500 psi.

40. The carbon reinforced polymer composite of claim 36, wherein an elongation of break of the composite is between about 800% and about 1400%.

41. The carbon reinforced polymer composite of claim 36, wherein the alphaolefin copolymer includes octene alpha-olefin LLDPE copolymer.

42. The carbon reinforced polymer composite of claim 31, further including an antioxidant additive.

43. The carbon reinforced polymer composite of claim 42, wherein the antioxidant additive includes one or more of sterically hindered phenols, secondary aromatic amines, phosphites, thioethers, or any combination thereof.4844. A thermoplastic polyolefin (TPO) composite including: a polypropylene homopolymer; a polypropylene copolymer; and an elastomer, wherein an increase in a density of the TPO composite as measured under ASTM D.792 is less than about 5% relative to the nominal density of the polypropylene homopolymer.

45. The TPO composite of claim 44, further including a carbon material including one or more of graphite, amorphous carbon, fullerene, carbon nanotubes, single layer graphene (SLG), few layer graphene (FLG), 3D graphene, or many layer graphene (MLG).

46. The TPO composite of claim 45, wherein a loading of the carbon material in the TPO composite is less than or equal to about 0.5 wt%.

47. The TPO composite of claim 44, wherein a density of the TPO composite as measured under ASTM D.792 is less than about 5% relative to the nominal density of the polypropylene homopolymer.

48. The TPO composite of claim 44, wherein a loading of the carbon material in the TPO composite is less than or equal to about 1 wt%.

49. The TPO composite of claim 44, wherein the TPO composite does not include a polypropylene-graft-maleic anhydride (PP-g-MA) compatibilizer.

50. The TPO composite of claim 44, wherein the polypropylene copolymer includes one or more of polypropylene impact copolymers, polypropylene random copolymers, or polypropylene graft copolymers.

51. The TPO composite of claim 44, wherein the elastomer includes an ethylene octene block copolymer.

52. The TPO composite of claim 44, wherein a loading of the polypropylene homopolymer is between about 60 wt% and about 80 wt%.4953. The TPO composite of claim 44, wherein a loading of the polypropylene copolymer is between about 10 wt% and about 25 wt%.

54. The TPO composite of claim 44, wherein a loading of the elastomer is between about 10 wt% and about 15 wt%.

55. The TPO composite of claim 44, further including an effective amount of an alpha-nucleating agent configured to increase the rate of polypropylene crystallization.

56. The TPO composite of claim 44, further including less than about 1 wt% of an alpha-nucleating agent.

57. The TPO composite of claim 56, wherein the alpha-nucleating agent includes one or more of talc, sodium benzoate, organic phosphate esters, 1,2,3,4-bis- dibenzylidene sorbitol (DBS), l,2,3,4-bis-( p-methoxybenzylidene sorbitol) (DOS), l,2,3,4-bis-(p- methylbenzylidene sorbitol) (MBDS), l,2,3,4-bis-(3,4-dimethylbenzylidene sorbitol), l,3:2,4-di(3,4- dimethylbenzylidene) sorbitol (DMDBS), or l,3:2,4-bis-o-(3,4- dimethylbenzylidene)-d-sorbitol.

58. The TPO composite of claim 44, further comprising 3D graphene including porous carbon agglomerates of porous carbon primary nanoparticles, each porous carbon primary nanoparticle including one or more interconnected bundles of electrically conductive graphene layers.

59. The TPO composite of claim 58, wherein each graphene layer is characterized by a linear dimension of between approximately 50 nm and 200 nm.

60. The TPO composite of claim 58, wherein the graphene layers include one or more of single layer graphene (SLG), few layer graphene (FLG), or many layer graphene (MLG).

61. The TPO composite of claim 58, wherein the graphene layers are arranged as one or more stacks connected to each other and defining a 3D porous scaffold structure including mesopores.5062. The TPO composite of claim 61, wherein the one or more stacks are disposed substantially orthogonal to each other.

63. The TPO composite of claim 58, wherein the porous carbon agglomerates are characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi).

64. The TPO composite of claim 44, further comprising 3D graphene including porous carbon agglomerates of porous carbon primary nanoparticles, wherein a respective porous carbon primary nanoparticle includes: an inner porous shell disposed about a center of the respective porous carbon primary nanoparticle and enclosing an inner porous carbon region; an outer porous shell enclosing an outer porous carbon region disposed between the inner porous shell and the outer porous shell; and an interconnected porous network disposed in and in fluid communication with the inner and outer porous carbon regions.

65. The TPO composite of claim 64, wherein the inner porous carbon region and the outer porous carbon region of the respective porous carbon primary nanoparticle are characterized by an average pore size and an average pore density associated with each region.

66. The TPO composite of claim 64, wherein the average pore size decreases along a radial direction from the center of the respective porous carbon primary nanoparticle to the outer porous shell of the respective porous carbon primary nanoparticle.

67. The TPO composite of claim 64, further including one or more intermediate porous shells disposed between the inner porous shell and the outer porous shell, wherein each of the intermediate porous shells encloses a respective intermediate porous carbon region.5168. The TPO composite of claim 64, wherein the porous carbon agglomerates are characterized by a Raman spectroscopy signature having an ID / IG ratio between approximately 0.95 and 1.05.

69. The TPO composite of claim 64, wherein the porous carbon agglomerates are characterized by a Brunauer-Emmett-Teller (BET) surface area between approximately 50 m2 / g and 300 m2 / g measured using nitrogen gas.

70. The TPO composite of claim 64, wherein the porous carbon agglomerates are characterized by an electrical conductivity of between about 500 S / m and 20,000 S / m when compressed at a pressure of about 12,000 pounds per square inch (psi).

71. A carbon reinforced thermoplastic polyolefin (TPO) composite including: between about 60 wt% and about 80 wt% polypropylene homopolymer; between about 10 wt% and about 15 wt% polypropylene impact copolymer; between about 10 wt% and about 15 wt% ethylene octene block copolymer; less than about 1 wt% an alpha-nucleating agent; and less than or equal to about 0.5 wt% three-dimensional (3D) graphene.

72. The carbon reinforced TPO composite of claim 71, wherein a flexural modulus of the TPO composite as measured under ASTM D.790 at a 1% secant modulus value is between about 187,000 psi and about 208,000 psi.

73. The carbon reinforced TPO composite of claim 71, wherein a percentage elongation at break as measured under ASTM D.638 of the TPO composite is between about 875% and about 1150%.

74. The carbon reinforced TPO composite of claim 71, wherein an ultimate tensile strength of the TPO composite as measured under ASTM D.638 is between about 3960 psi and about 4450 psi.

75. The carbon reinforced TPO composite of claim 71, wherein a notched Izod impact strength of the TPO composite as measured under ISO 180 / 1 A at 23 °C is between about 20 kJ / m2and about 40 kJ / m2.5276. The carbon reinforced TPO composite of claim 71, wherein a density of the TPO composite as measured under ASTM D.792 is less than about 0.95 g / cc.

77. A carbon reinforced thermoplastic polyolefin (TPO) composite including: a polypropylene homopolymer; a polypropylene copolymer; an elastomer; and three-dimensional (3D) graphene, wherein a decrease in a flexural modulus of the TPO composite as measured under ASTM D.790 at a 1% secant modulus value is less than about 35% relative to a nominal flexural modulus of the polypropylene homopolymer.

78. A carbon reinforced thermoplastic polyolefin (TPO) composite including: a polypropylene homopolymer; a polypropylene copolymer; an elastomer; and three-dimensional (3D) graphene, wherein a decrease in an ultimate tensile strength of the TPO composite as measured under ASTM D.638 is less than about 35% relative to a nominal ultimate tensile strength of the polypropylene homopolymer.

79. A carbon reinforced thermoplastic polyolefin (TPO) composite including: a polypropylene homopolymer; a polypropylene copolymer; an elastomer; and three-dimensional (3D) graphene, wherein the TPO composite is characterized by one or more of: an increase in a density of the TPO composite as measured under ASTM D.792 of less than about 5% relative to the nominal density of the polypropylene homopolymer; a decrease in an ultimate tensile strength of the TPO composite as measured under ASTM D.638 of less than about 35% relative to a nominal ultimate tensile strength of the polypropylene homopolymer; or53a decrease in an ultimate tensile strength of the TPO composite as measured under ASTM D.638 of less than about 35% relative to a nominal ultimate tensile strength of the polypropylene homopolymer.54

Images