Graphene superparticles, methods for manufacturing them, and their uses

Abstract

The present invention relates to a method for producing graphene superparticles, wherein the particle size is 0.5 microns to 100 microns in diameter d 50 The present invention relates to a method for obtaining graphene superparticles by dispersing a graphene material having a certain property in a solvent, preferably by adding an additive to the dispersion, and at least partially removing the solvent from the dispersion thus obtained by spray drying.

Description

[Technical Field]

[0001] The present invention relates to a method for producing graphene superparticles, the graphene superparticles themselves, and the use thereof.

[0002] Technical literature, such as Roempp online (ROEMPP editorial team, Balgar T, Graphene, RD-07-02758 (2010) in Boeckler F., Dill B., Eisenbrand G., Faupel F., Fugmann B., Gamse T., Matissek R., Pohnert G., Ruehling A., Schmidt S., Sprenger G., ROEMPP [Online], Stuttgart, Georg Thieme Verlag, [September 2022] https: / / roempp.thieme.de / lexicon / RD-07-02758), discusses various aspects of graphene, including its manufacturing, properties, and uses.

[0003] Similar to graphite, each carbon atom in graphene is covalently bonded to three adjacent atoms by sigma bonds. The CC bond length is 142 pm. The atoms are sp 2 It is hybridized, and the sigma bonds lie within a single plane. Therefore, graphite has a planar structure. Partially filled p z Orbitals remain in each atom. These p z The orbitals are perpendicular to the bonding plane and form the most important delocalized pi electron system when determining the electronic properties of graphene.

[0004] Crystallographically, graphene is a unit cell vector

number

[0005] The methods described below can be carried out using all graphenes specified thereafter. The definitions outlined earlier are applicable to these graphenes.

[0006] In the context of this invention, "graphene material" means a material in accordance with ISO / TS 80004-13, namely graphene, graphene carbon material, single-layer, double-layer and triple-layer graphene, epitaxial graphene, exfoliated graphene, multi-layer graphene, multi-layer graphene, multi-layer nanoribbon, graphene nanoplate, graphene nanoplatelet, graphene nanosheet, graphene microsheet, graphene nanoflake, graphene nanoribbon, graphene oxide, graphene oxide nanosheet, multi-layer graphene oxide, graphene quantum dot, graphite, graphite nanoplate, graphite nanosheet, graphite nanoflake, graphite oxide, reduced graphene oxide, or mixtures thereof.

[0007] In the context of this invention, fillers are understood to mean boron nitride, nitrides in general, carbon-based materials (diamines), aluminum-based materials, metal particles and alloys, TiO2, ZnO, MgO, noble metals and their alloys, as well as metal salts, silica and silicates, SiC materials, layered materials (WS2, vanadium-based, silicon-based), composite components (such as fibers), flame retardants, impact modifiers, pigments, and UV stabilizers.

[0008] Graphene materials are used in many technical fields, as described, for example, in European Patent Application No. 21150690. Materials composed of graphene materials, such as so-called composite materials, also constitute part of the prior art.

[0009] International Publication No. 2016078664 discloses a composite material in which a structure-granting material is imparted to a given macroscopic surface by using appropriately selected graphene as a binder material.

[0010] The polynorbornene / graphene oxide composite material described in Korean Registered Patent No. 1190014 plays a role in adjusting gas barrier properties and various mechanical parameters in a layered structure.

[0011] Korean Published Patent No. 20190048574 outlines, for example, the production of a composite material containing graphene oxide using a 10 g / l dispersion in distilled water. Thus, a graphene material with a weight percentage of only 1% is achieved. The graphene oxide particles partially aggregated to form particles having an approximately spherical shape and a diameter of less than 30 μm. Another portion was in the form of flakes of a different shape. In this case, a free-flowing composite material was not obtained.

[0012] In the paper "Supraparticles: Functionality from Uniform Structural Motifs" by S. Wintzheimer et al., ACS NANO, 12 (2018), 5093-5120, nanoparticles are found to be components of superparticles. Using the controlled aggregation of only such individual nanoparticles, superparticles with specific electronic, plasmon, magnetic, and / or photon properties can be obtained. To induce this aggregation, van der Waals or electrostatic forces present between nanoparticles are utilized by spray drying, or alternatively, nanoparticles are bonded in an environment where they are formed by the sol-gel method, or ultrasonic chemistry is employed. In particular, in the case of spray drying, the geometric specificity of the apparatus used for this purpose, and its relationship to the properties of the thus aggregated product, are not discussed.

[0013] Graphene materials are commercially available as powders and often have a very low bulk density in the range of, for example, 2 to 400 g / l. In addition to the low bulk density, most graphene materials also have low fluidity and / or generate a large amount of dust during transfer by gravity-driven flow. This is considered to deteriorate the handling property, cause problems during metering and measurement, and be significant in terms including environmental protection and operator safety.

[0014] The deterioration of the handling property is evident when the powder is incorporated into the elastomer system, for example, as in the case of rubber kneading. The production of a good filled rubber compound depends on incorporating the powdery filler at an appropriate time over an appropriate period. These are poured into the mixing chamber by a hopper and then pushed in the direction of the rotating roller by a pneumatic piston. The shear force acting during such a mixing process decomposes the aggregates of the filler and thus contributes to its dispersion. Therefore, the maximum filler level that can be achieved is substantially determined by the shear force acting thereon. This is a problem because, especially in the case of soft polymer mixtures, it is not possible to generate a large shear force for material-related reasons.

[0015] For example, it is known to generate fine graphite or graphene aggregates in electrode manufacturing. However, this conventional material is not sufficiently free-flowing to enable its use in conventional compounders or extruders due to the size of the aggregate particles.

[0016] Similarly, it is also known that the spray drying process can be utilized for the optimization of the powder system in that spherical aggregates can be obtained, for example, by spray drying of a graphene dispersion. However, powders composed of graphene materials having improved fluidity have not been found so far.

[0017] In order to characterize the fluidity of the material, in the context of the present invention, several test methods are employed, namely, the following measurements or determinations: - Angle of repose compliant with ISO 4324, - Dynamic avalanche angle, and - Hausner coefficient compliant with ASTM 527.

[0018] A further measured value in the context of the present invention is the dust value compliant with DIN 55992.

[0019] The above parameters are well-known to those skilled in the art and are confirmed by the test methods outlined below. Here, the angle of repose and the avalanche angle are expressed in degrees (°).

[0020] The better at least two of these values of the material, and even better three of these values, i.e., - a low angle of repose, - a low dynamic avalanche angle, - a low Hausner coefficient the better the flowability of the material. Further, the smaller the dust value, the less dust is obtained in the processing of the material used in the context of the present invention, i.e., the material presented and claimed here.

[0021] The terms "dust value" and "dust generation" are synonymous in the context of the present invention. Conventionally produced graphene powder is cohesive, which is synonymous with high measured values, and thus has only low flowability and high dust generation. Such powders are either difficult to process or can only be processed with elaborate technical safety measures, and when the dust value is high, only a low bulk density is achieved.

[0022] Therefore, a technical approach is needed to provide a powdered graphene material with improved flowability.

[0023] Similarly, there is an ongoing need to reduce the amount of dust generated. This is because, firstly, the dust causes contamination and makes it difficult to measure the amount of filler actually introduced into the matrix system. Secondly, for occupational health and environmental protection reasons, it is essential to remove the dust by suction or other means.

[0024] Furthermore, the dustiness and generally low bulk density of graphene material increase the cost of introducing the material into the desired matrix system. For example, corresponding problems arise when manufacturing thermoplastic compound materials filled with graphene material in an extruder. For these reasons, it is difficult or impossible to ensure compliance with essential time-dependent requirements when introducing powdered graphene material during the manufacturing process of thermoplastic systems.

[0025] Furthermore, the conductivity of graphene, known to those skilled in the art, limits the use of graphene material in electrical insulating composite materials. For this purpose, additional electrical insulating materials are required. However, the use of such materials has the disadvantage that the thermal conductivity of graphene is further limited. Therefore, in order to achieve a complete electrical insulating effect with high thermal conductivity, it is necessary to efficiently connect the graphene material to the insulator.

[0026] Therefore, the object of the present invention was to improve a spray drying method for producing a powder containing a freely flowable graphene material so that the graphene material or its compound or masterbatch has improved fluidity and / or less dust is generated during processing than conventional methods. The resulting graphene material was further thermally conductive and simultaneously electrically insulating.

[0027] The objective is a method for producing graphene superparticles, (a) Particle size diameter d from 0.5 μm to 100 μm 50 Mix at least one graphene material having a solvent, (b) Add to the dispersion obtained in step (a) and any step (a1) Based on the mass of the graphene material used, 0 to 100% by weight, preferably 0.1 to 100% by weight, of a dispersion aid, emulsifier, wetting aid, and / or defoaming agent. Add, after that, (c) Remove the solvent from the dispersion obtained in step (b) by spray drying, Obtaining graphene superparticles This was achieved by providing a method.

[0028] Preferably, graphene material, or at least one further material (a1) selected from SiO2, aluminum oxide, TiO2, MgO, ZnO, SbO, organic fillers, polymers, or phosphates, chlorides, sulfates, nitrites, is used simultaneously or sequentially, and the particle size diameter d of at least one further material is 50 It is at least one-tenth the size of graphene material (a).

[0029] A more preferred (a1) material is selected from the group consisting of graphene material, aluminum oxide, TiO2, MgO, ZnO, SbO, organic fillers, or selected from phosphates, chlorides, sulfates, nitrites, and at least one further material with particle size diameter d 50 It is at least one-tenth the size of graphene material (a).

[0030] Surprisingly, it was found that graphene dispersions containing additives could be spray-dried.

[0031] Further graphene materials, SiO2, aluminum oxide, TiO2, MgO, ZnO, SbO, organic fillers, polymers, or additional materials selected from the group of phosphates, chlorides, sulfates, and nitrites can be optionally added. It optionally contains a dispersing agent, emulsifier, wetting agent, and / or defoaming agent. The dispersion of the graphene material can be spray-dried, and it has been found that improved fluidity and the desired properties of thermal conductivity and electrical insulation of the spray-dried material are achieved.

[0032] During the operation of drying the aqueous or alkanol solution to which the additive is added, the surface of the graphene material particles is wetted or has been wetted by the additive, whereby it is stabilized. By spray-drying, using aggregation, graphene superparticles of the graphene material are obtained.

[0033] The aggregated graphene particles obtained after step (c) are superparticles of graphene particles. These are referred to as "graphene superparticles" or "superparticles" in the context of the present invention. These graphene superparticles preferably have a spherical or substantially spherical shape and a particle diameter d of 1 μm to 500 μm, preferably 5 μm to 250 μm, more preferably 50 μm to 100 μm. 50 having.

[0034] In the context of the present invention, the particle diameter is measured using a Partica laser scattering particle size analyzer LA-950V2 from Rentsch Technology. All particles were analyzed in water. Here, the pump transport circulation rate was set to 6 and the stirrer speed was set to 6. For the analysis of the starting material, the ultrasonic wave was set to level 6 for 1 minute. The graphene superparticles were measured in a 0.001 wt% soap solution to stabilize them.

[0035] The method according to the present invention has the advantage that the graphene superparticles obtained in this way have better fluidity than conventional graphene particles. Here, the graphene superparticles have been found to have good fluidity only when the particle diameter d exceeds at least 40 μm. 50 Graphene superparticles having a particle diameter d of at least 50 μm, preferably at least 70 μm, have particularly good fluidity. 50 having.

[0036] The graphene content of the graphene superparticles of the present invention is at least 50% by weight.

[0037] The respective amounts of graphene material and further material (a1) in step (a) are 50:50, preferably 60:40, and more preferably 80:20.

[0038] Graphene superparticles were measured by Brunauer-Emmett Teller (BET) surface area analysis, and were found to be 400 m². 2 Less than / gBET, preferably 300m 2 It has a surface area less than / gBET.

[0039] In this context, the use of additives such as dispersants, emulsifiers, wetting agents, and / or defoamers facilitates the handling of the dispersion without affecting the inherent properties of the graphene material.

[0040] Similar to the improved fluidity, the bulk density of the resulting graphene superparticles also increases. Furthermore, the material obtained by this method can be easily measured and added to any conventional matrix material. Moreover, the processing of graphene superparticles obtained according to the present invention results in relatively low dust levels. Thus, operational safety is improved. Furthermore, the usability of the further processed material is also maintained. For example, in conventional compounders, graphene superparticles can be broken down into graphene material using active shear forces in a matrix material, preferably a polymer, monomer, or solvent, thereby maintaining the original physical properties.

[0041] Similarly, the present invention relates to graphene superparticles, - An angle of repose in accordance with ISO 4324 of 50°~20°, preferably 40°~25°, more preferably 37.5°~30°, and particularly preferably 37°~27.5°, and - Dynamic avalanche angles of 65°~30°, preferably 55°~35°, most preferably 45°~40°, and / or - Hausner coefficients in accordance with ASTM 527, of 1.5 to 1, preferably 1.4 to 1.1, more preferably 1.3 to 1.2, or - Dust values ​​conforming to DIN 55992 Type I, of 10 to 0.001, preferably 5 to 0.01, and more preferably 3 to 0.1. The present invention provides graphene superparticles characterized by having the following properties:

[0042] The graphene superparticles obtained according to or in accordance with the present invention provide a powder that is free-flowing yet does not produce dust.

[0043] The graphene superparticles according to the present invention preferably have the features claimed simultaneously. Thus, the graphene superparticles have an angle of repose in accordance with ISO 4324 of 50° to 20°, a dynamic avalanche angle in accordance with 65° to 30°, a Hausner coefficient in accordance with ASTM 527 of 1.5 to 1, and a dust value in accordance with DIN 55992 Type I of 10 to 0.001. These graphene superparticles preferably have a diameter d of 1 μm to 500 μm. 50 It has.

[0044] The graphene superparticles obtained according to the present invention or in accordance with the present invention can be collected into three different containers for classification purposes and thus divided into three sizes.

[0045] The so-called "crude material" can be collected vertically into a collection container downstream of the drying chamber after step (c) of the method according to the present invention. The powder containing graphene superparticles, which consist of graphene particles obtained according to the present invention or the present invention, is subjected to a correspondingly low level of shear force during the method, which means that there is little debris obtained.

[0046] Downstream from the drying chamber, the powder can be introduced into a cyclone. Here, the so-called "particulate fraction" is separated from the so-called "cyclone product." The cyclone product is subjected to a large shear force by centrifugal force, and as a result, graphene superparticles in particular tended to break down. The particulate fraction can be collected on a filter mat downstream of the cyclone.

[0047] The present invention also, - In particular, thermally conductive materials and thermally conductive adhesives in the fields of batteries, sensors, ICs, and LEDs, such as films, underflow materials, pourable electronic materials, materials with phase transitions, thermal pastes, sealing compounds, - Composite materials based on thermoplastic resins, thermosetting resins, and / or elastomers having increased electrical conductivity and / or thermal conductivity, or for EMI shielding, particularly in the field of housings for electrical components, motors, battery packs, and pipelines. - Coatings and varnishes that are thermally conductive and / or electrically conductive, or for use in EMI shielding sectors. - Thermally conductive and / or conductive oils, coolants, or inks This invention provides for the use of graphene superparticles obtained according to or in accordance with the present invention in the following applications.

[0048] In particular, graphene superparticles obtained according to the present invention or in accordance with the present invention are A standard thermoplastic resin, preferably selected from PE, PP, PS, PVC, alpha-olefin, butadiene derivatives, and / or Vestenamer®. Industrial thermoplastic resins, preferably PET, PMMA, PC, POM, PA, PBT, PEBA, TPU, PU, ​​and / or TPE, High-performance thermoplastic resins, preferably PPS, PEEK, PES, PI, and / or PEI, A paste containing copolymers, elastomers, preferably silicones, more preferably room temperature crosslinked (RTV) silicones, high temperature crosslinked (HTV) silicones, liquid silicone rubber (LSR), heat crosslinked rubber (HCR), acrylates, and / or polysiloxanes and oligosiloxanes. Polyurethane, rubber, preferably styrene-butadiene rubber (SBR), butadiene rubber (BR), and / or natural rubber, thermosetting resin, preferably polyurethane, polyester resin, phenolic resin, epoxy resin, acrylate resin, and / or silicone resin, Solvents, preferably aprotic-nonpolar, aprotic-polar, and / or protic solvents. Oil, preferably mineral oil, silicone oil, and / or process oil Suitable for use in [location / area].

[0049] More preferably, graphene superparticles obtained according to the present invention or in accordance with the present invention are used as additives in the plastics processing industry. These are preferably used in the compounding, extrusion, or injection molding of plastics.

[0050] The claimed benefit of the use is that the incorporation of graphene becomes practically feasible in several cases. Furthermore, the use of the present invention enables the easy and reliable processing of graphene, including so-called "rapid injection molding (RIM)."

[0051] This method allows for the efficient use of high-performance fillers such as graphene without compromising the high-performance properties of the matrix, as is the case with PA12, for example.

[0052] When used as an additive, graphene superparticles enable improvements in thermal, electrical, and / or mechanical properties, such as improved degree of extrusion, in high-performance polymers in high-performance applications where filler content must be kept low to maintain matrix properties.

[0053] The use of graphene superparticles according to the present invention also achieves a favorable lubrication effect for easy compounding and extrusion, which is difficult with fillers. Furthermore, conductivity is improved.

[0054] Further advantages arise when handling in masterbatch processing for thermoplastic resins, epoxys, and elastomers, and / or when handling concentrates commonly referred to as masterbatches.

[0055] When used in gas membranes or gas conduction systems, the tendency for leakage is similarly reduced.

[0056] The present invention will be described in more detail below.

[0057] The method according to the present invention is schematically shown in Figure 2.

[0058] Step (a) of the method according to the present invention involves a particle size diameter d of 0.5 μm to 100 μm. 50 A graphene material having [a certain characteristic] is mixed with a solvent. Further materials can be optionally added ((step a1)). These materials may be, for example, further graphene materials, but can also be selected from the group consisting of SiO2, aluminum oxide, TiO2, MgO, ZnO, SbO, organic fillers, polymers, or phosphates, chlorides, sulfates, and nitrites.

[0059] The particle dispersion obtained after step (b) preferably has a particle diameter d of 0.5 μm to 100 μm, more preferably 0.5 μm to 60 μm, and more preferably 2 μm to 40 μm. 50 It has.

[0060] The graphene material in step (a) has the same particle size diameter d as the graphene material obtained in step (b). 50 It has.

[0061] The graphene particles in step (a) are at least an order of magnitude larger than any further graphene particles, aluminum oxide particles, SiO2 particles, TiO2 particles, MgO particles, ZnO particles, SbO particles, polymer particles, organic fillers, or phosphates, chlorides, sulfates, or nitrites used in step (a1).

[0062] Further graphene material, aluminum oxide particles, SiO2 particles, TiO2 particles, MgO particles, ZnO particles, SbO particles, polymer particles, organic fillers, or phosphates, chlorides, sulfates, nitrites with diameter d used in step (a1) of the method according to the present invention 50 This is the diameter d of the initial graphene particle. 50 Smaller than the diameter d of the material used in step (a1) of the method according to the present invention. 50 The diameter d of the graphene particles used in step (a) 50 More preferably at least 1 / 10th smaller, even more preferably at least 1 / 20th smaller, and most preferably at least 1 / 50th smaller. The material used in step (a1) is advantageously d with a diameter of 500 nm or less. 50 It may have.

[0063] Preferably, according to the present invention, the material used in step (a1) is a hydrophobic material. Therefore, further graphene materials, aluminum oxide particles, SiO2 particles, TiO2 particles, MgO particles, ZnO particles, SbO particles, polymer particles, organic fillers, or phosphates, chlorides, sulfates, and nitrites used according to the present invention preferably do not have (surface) modifications that increase their water solubility, in contrast to hydrophilic materials.

[0064] Due to the improved material properties, it is advantageous that the graphene superparticles obtained in step (c) can be broken down into graphene material in a compounder while maintaining their original physical properties by using active shear forces in a matrix material, preferably a polymer, monomer, or solvent.

[0065] In step (a1), the organic filler used may be a polymer selected from PE, PP, PS, PVC, alpha-olefins, butadiene derivatives, Vestenamer® (a rubber additive from Evonik GmbH in Essen, Germany), industrial thermoplastics, preferably PET, PMMA, PC, POM, PA, PBT, PEBA, TPU, PU, ​​TPE, and high-performance thermoplastics, preferably PPS, PEEK, PES, PI, and PEI.

[0066] In the context of the present invention, the inorganic filler is also considered to contain a salt that is insoluble in the solvent used in step (a).

[0067] Furthermore, it may be advantageous to select the solvent in step (a) from water, distilled water, alkanol, and preferably ethanol.

[0068] The solvent can be selected from hexane, chlorobenzene, toluene, tetrachloromethane, dichloromethane, water, distilled water, ethanol, or a mixture of these solvents.

[0069] Suitable solvents for graphene materials and additives, including these and others, are known to those skilled in the art.

[0070] In the method according to the present invention, it may be advantageous to produce the dispersion in batch or continuously. In the case of batch formulation in step (a) and, if appropriate, (a1), the graphene material or the material used in step (a1) can be weighed and gradually added to the solvent. Here, a suitable stirring unit, such as an ultrasonic finger or Ultraturrax, can be used. It is observed that the viscosity of the dispersion increases as the mass proportion of the graphene material or further material in step (a1) increases.

[0071] More preferably, a homogeneous dispersion is obtained in step (a) and, if appropriate, in (a1). The properties of the dispersion are very important in carrying out step (c) of the method, because the size of the graphene superparticles is influenced by the viscosity, surface tension, density and mass ratio of the graphene material, as well as the shape of the drying chamber.

[0072] As previously described, step (c) of the method according to the present invention involves subjecting the dispersion obtained in step (b) to spray drying. The drying method in step (c) is preferably the following steps: Step (b) involves spraying the dispersion obtained in step (b) into an inert gas stream using a spray unit to at least partially evaporate the solvent in the droplets formed by the spray. Includes.

[0073] In the spray drying method, a dispersion consisting of graphene material and optional additives is atomized by applying a shear force. During this process, an initial film is formed, and then the film separates into numerous droplets. Here, the droplets are surrounded by a high-temperature gas stream, preferably an inert gas, more preferably nitrogen, and are preferably in the range of 80 to 400°C. This temperature can be adjusted depending on the solvent.

[0074] In the context of the present invention, graphene particles obtained according to or in accordance with the present invention are referred to as "superparticles" or "graphene superparticles" when they are in an aggregated form.

[0075] In step (c), the solvent in the droplet evaporates and is absorbed by the gas flow. This cools the gas. Due to the evaporation of the solvent, the volume of the droplet continuously decreases. Thus, as the droplet passes through the gas flow, the mass ratio of graphene material and any additives in the droplet increases. The drying of the droplet and the resulting volume reduction are initially linear until a so-called "rocking point" is reached. At the rocking point, a hard outer shell is formed, while the core of the graphene superparticles being formed remains moist, meaning that solvent residues are present in the core of the graphene superparticles and the additives. Further drying is slower because moisture needs to transfer from the core to the surface. The drying rate can be controlled by the temperature of the inert gas flow during step (c) of the method.

[0076] If this drying rate is very high, it is possible to obtain hollow graphene superparticles.

[0077] When the drying rate is low, solid graphene superparticles are usually obtained.

[0078] In this second case, attention must be paid to the required residence time in the drying chamber; otherwise, drying will be incomplete.

[0079] Furthermore, the particle diameter of the graphene superparticles can be adjusted by the drying rate. Further means of influencing the size of the graphene superparticles are the selection of a spraying unit, which is preferably a two-phase nozzle, and the selection of the ratio of the mass flow rate of gas to the sprayed dispersion, known as the air-to-liquid ratio.

[0080] Although not bound by any particular theory, as schematically shown in Figure 3, there may be various pathways 1-4 for forming graphene superparticles during the implementation of the method according to the present invention. These pathways depend on factors including the temperature of the inert gas flow. Depending on the pathway that follows the implementation of step (c), the graphene superparticles will have different shapes F, J, and P, each with different properties for each pair.

[0081] The dispersion can be atomized, for example, by a two-phase nozzle. In this case, the required shear energy is supplied by the gas flow, which is significantly accelerated in the constricted section. Depending on the gas volumetric flow rate and the resulting gas velocity at the nozzle outlet, a higher or lower shear force is applied. This changes the droplet size and droplet size distribution of the dispersion.

[0082] Depending on the solvent, it is possible to use graphene material in a mass percentage of 5% to 50% by weight. The mass percentage of the additive used in wt% is based on the mass of the graphene material used.

[0083] The additives can be dispersed using a suitable agitator unit. To prevent demixing, the dispersion is preferably stirred continuously.

[0084] In the case of continuous preparation in step (a) and, if appropriate, step (a1), the graphene material or further material from step (a1) can be added to the mixture of solvent and additive by a suitable machine, preferably by a conveyor screw. If two phases are obtained, they can be pumped through a dispersion chamber. A corresponding agitator unit is required for the necessary energy input. The selection of the dispersion chamber and the energy input to be set are known to those skilled in the art. The dispersion is then continuously supplied to the agitator unit.

[0085] In step (b) of the method according to the present invention, if present, one additive may be selected from the group consisting of a dispersant, an emulsifier, or a wetting agent, and / or an antifoaming agent.

[0086] The at least one additive in step (b) can be used in a mass percentage of 0% to 100% by weight, preferably 0.1% to 100% by weight, and more preferably 0.1% to 10% by weight, based on the mass of the graphene material used.

[0087] At least one wetting or dispersing agent can preferably be selected from copolymers based on oxyalkylene glycol alkenyl ethers or polyalkylene oxide alkenyl ethers and unsaturated dicarboxylic acid derivatives. Such copolymers are disclosed in the patent specification, European Patent No. 114292, and ensure, for example, the production of binder-free, co-solvent-free, or VOC-free pigment concentrates based on transparent iron oxide.

[0088] In step (c) of the method according to the present invention, the spray unit may be a device having at least one two-phase nozzle and / or the inert gas used may be nitrogen, preferably dry nitrogen, the temperature of the inert gas stream may be set more preferably from above the cooling limit temperature of the solvent to 200°C to 400°C, and more preferably in the range of 220°C to 300°C and / or the spray droplets may have a size of 30 to 1000 μm.

[0089] The size of the sprayed droplets is determined by the force of the sprayer, which is known to those skilled in the art, and can be adjusted by the nitrogen flow rate or by the shear effect of the sprayer gas flow rate.

[0090] The present invention will be described in detail by examples without limiting the subject matter of the present invention.

[0091] The SEM images shown below were evaluated using a JEOL NeoScope by scattering the powdered material to be examined onto an adhesive graphene film and carefully removing the excess material with a bellows set. The SEM images shown in the context of this invention were recorded at 10kV.

[0092] Hausner coefficients compliant with ASTM 527 The Hausner coefficient was determined in accordance with ASTM 527. This is also a measure of the compressibility of the powder.

[0093] To determine the Hausner coefficient, the ratio of bulk density to compaction density is calculated. This is done by introducing 100g of powder material into a cylinder. Depending on the bulk density, a 100ml or 250ml cylinder can be used. The powder is introduced gradually and carefully. The volume of the loose layer is read; this is the bulk volume. The quotient between the mass of the introduced powder and its bulk volume is the bulk density.

[0094] Afterward, the powder is compacted until no further volume change is observed. The volume remaining at that point is the compacted volume, and this is then read.

[0095] The compaction density is the quotient between the mass of the introduced powder and the compacted volume.

[0096] The Hausner coefficients, calculated from bulk density and compaction density, can be classified into various evaluation classes as shown in Table 1.

[0097] [Table 1]

[0098] Dynamic avalanche angle measured with Revolution Powder Analyzer Similarly, dynamic avalanche angle is a measure of powder fluidity and can be measured directly.

[0099] In the context of this invention, we used the Revolution Powder Analyzer model Rev2015 from PS Prozesstechnik GmbH. This involved loading a specific amount into a rotating drum and using a camera to determine the angle at which the material began to form an avalanche, as shown in Figure 4a. A smaller avalanche angle (ava,h) between surfaces formed by horizontal (h) particles at the avalanche joint indicates better material flowability. The avalanche angle was measured mathematically in the positive direction between (ava) and horizontal (h). The operating modes of this Powder Analyzer, as well as the variables measured therein, are known to those skilled in the art. Further details can be found, for example, in the following article by Amado: "Advances in SLS powder characterization", 22nd Annual International Solid Freeform Fabrication Symposium - An Additive Manufacturing Conference, SFF, 2011, pp. 438-452.

[0100] 100 ml of powder material was weighed and introduced into a glass chamber. The chamber rotated at 0.5 rpm, thereby creating an angle. When the dynamic avalanche angle, the maximum value of this angle, was reached, the powder began to flow down the slope. A camera recorded the movement of the powder, thus continuously monitoring the dynamic avalanche angle. Furthermore, the avalanche energy of the downward-flowing powder was calculated.

[0101] The dynamic avalanche angle can vary from 70° for very low-flow powders to 30° for very efficiently flowing powders.

[0102] The measurement parameters of the fluidity program corresponded to the standard settings for dark-colored powders: 0.5rpm • 150 avalanche occurrences • Avalanche threshold 0.65% Camera: Shutter speed 6ms, gain 6dB (black powder), 10 frames / second

[0103] Homogeneity and flow characteristics can be directly calculated from the standard deviation of the dynamic avalanche angle and avalanche energy.

[0104] Tilt angle compliant with ISO 4324 Measuring the angle of inclination provides further explanation for the powder's fluidity.

[0105] In the context of this invention, 100 ml of powder material was introduced into a funnel having a 10 mm outlet. The outlet was closed. The funnel was fixed at a distance of 7.5 cm from a plate having a diameter of 10 cm and a height of 25 cm. When the outlet of the funnel was opened, the powder flowed onto the plate. In this way, the powder formed a cone with an angle of inclination of the object.

[0106] The inclination angle can be classified into various evaluation classes as shown in Table 2.

[0107] [Table 2]

[0108] Scanning electron microscope (SEM) The SEM images disclosed herein were obtained using a FlexSEM 1000 II VP-SEM. For this purpose, the powder to be examined was sprinkled onto an adhesive graphene film. Excess material was carefully removed with a bellows set. Images were recorded at 10kV.

[0109] Electrical insulation Electrical insulation was measured in accordance with ISO 62631 using an FE50 ring electrode and a Mili-TO 3 ohmmeter (Fischer Elektronik).

[0110] Thermal conductivity Thermal conductivity was determined in equilibrium according to ASTM E1530-19 using a two-dimensional sample approximately 10 mm thick in contact with a 120 silicone type (Wakefield-Vette) thermal joint compound, using a guarded hot plate (Thermtest GHFM-02). The upper plate was set to 35°C, while the lower plate was set to 15°C. Measurements were started after a 60-minute equilibrium period.

[0111] Devices used in the examples: Somakon MP-GL laboratory mixer, Buechi B290 spray dryer, UltraTurrax IKA T50. The spray dryer used is schematically shown in Figure 4b.

[0112] Example 1. Gamor GO The graphene material used was Gamor GO (manufactured by Gamor Inc., located in Orlando, Florida, USA).

[0113] Figure 5 shows an SEM image of graphene material. It is in the form of particles, and the particles are partially in the form of aggregates.

[0114] Figure 6 shows the corresponding particle size distribution.

[0115] Here, the following characteristic diameter is measured: d 10 0.94 μm, d 50 2.42 μm, d 90 5.53 μm.

[0116] Manufacturing of dispersions: A dispersion consisting of ethanol and Gamor GO is prepared as follows.

[0117] Add Gamor GO to ethanol, stirring until it reaches a weight of 20% by weight. Then, disperse the dispersion using an H7 ultrasonic finger. The device is set to 100% amplitude and 0.75 cycles. Disperse for 5 minutes first. Then, close the container and shake vigorously for 30 seconds. Repeat this procedure a total of three times.

[0118] Once a homogeneous dispersion is obtained, it is stirred to prevent separation. This is done using a stirrer plate and a football-shaped stirrer bar at 600 rpm.

[0119] During step (c), the dispersion was stirred to prevent separation. The process parameters during step (c) were: Inlet temperature: 100℃, Outlet temperature: 70℃, Nozzle gas flow rate: 366 l / min Aspirator output 50% (about 20m 3 ( / h), pump output 50% (approx. 8 ml / min), Air-to-liquid ratio approximately 0.9 That was indeed the case.

[0120] The resulting graphene superparticles were formed in the form of loose aggregates held together solely by van der Waals forces, and therefore could be broken under moderate shear forces. Such forces were generated, for example, in the cyclone of a spray dryer. Therefore, the graphene superparticles were withdrawn from directly below the spray chamber, and any particles downstream of the cyclone were discarded. These consisted only of fragments of graphene superparticles.

[0121] Figure 7 shows a SEM image of graphene superparticles.

[0122] Figure 8 shows that there is a wide range of particle sizes that do not adversely affect the processability of graphene material.

[0123] The particle size distribution of graphene superparticles manufactured according to the present invention is evident from Figures 7 and 8. The graphene superparticles have a diameter of more than 40 μm.

[0124] Example 2: First Graphene pure graph 20 The graphene material used was First Graphene pure graph 20 (manufactured by First Graphene, Inc., located in Henderson, Australia).

[0125] Figure 9 shows an SEM image of graphene material. It is in the form of platelets, which are partially in the form of aggregates.

[0126] Figure 10 shows the corresponding particle size distribution.

[0127] Here, the following characteristic diameter is measured: d 10 13 μm, d 50 22 μm, d 90 40 μm.

[0128] Manufacturing of dispersions: A dispersion consisting of water, First Graphene pure graph 20 (manufactured by First Graphene, Henderson, Australia), and AEROXIDE® Alu 65 (manufactured by Evonik, Essen, Germany) is prepared as follows.

[0129] Dissolve the appropriate additive, TEGOMER® DA 850 (manufactured by Evonik GmbH, Essen, Germany), in water. Stir the First Graphene pure graph 20 until it reaches a weight of 25% by weight. Then, disperse the dispersion using an H7 ultrasonic finger. The device is set to 100% amplitude and 0.75 cycles. Disperse for 5 minutes first. Then, close the container and shake vigorously for 30 seconds. Repeat this procedure a total of three times.

[0130] Once a homogeneous dispersion is reached, stir it to prevent separation. This is done using a stirrer plate and a football-shaped stirrer bar at 600 rpm.

[0131] During step (c), the dispersion was stirred to prevent separation. The process parameters during step (c) were: Inlet temperature: 140℃, Outlet temperature: 90℃, Nozzle gas flow rate: 366 l / min Aspirator output 50% (about 20m 3 ( / h), pump output 50% (approx. 8 ml / min), Air-to-liquid ratio: approximately 0.85 That was indeed the case.

[0132] The resulting graphene superparticles were formed in the form of loose aggregates held together solely by van der Waals forces, and therefore could be broken under moderate shear forces. Such forces were generated, for example, in the cyclone of a spray dryer. Therefore, the graphene superparticles were withdrawn from directly below the spray chamber, and any particles downstream of the cyclone were discarded. These consisted only of fragments of graphene superparticles.

[0133] Figure 11 shows a SEM image of graphene superparticles.

[0134] Figure 12 shows that there is a wide range of particle sizes that do not adversely affect the processability of graphene material.

[0135] The particle size distribution of graphene superparticles manufactured according to the present invention is evident from Figures 11 and 12. The graphene superparticles have a diameter of an order of magnitude greater than 80 μm.

[0136] Example 3: Avanzare av PLAT 2 The graphene material used was Avanzare av PLAT 2 (manufactured by Avanzare, located in La Rioja, Spain).

[0137] Figure 13 shows an SEM image of the starting graphene material. It is in the form of platelets, which are partially in the form of aggregates.

[0138] Figure 14 shows the corresponding particle size distribution.

[0139] Here, the following characteristic diameter is measured: d 10 0.9 μm, d 50 2.7 μm, d 90 13 μm.

[0140] Manufacturing of dispersions: A dispersion consisting of water and Avanzare av PLAT 2 (manufactured by Avanzare, located in La Rioja, Spain) is prepared as follows.

[0141] Dissolve the appropriate additive, TEGOMER® DA 850 (manufactured by Evonik GmbH, Essen, Germany), in water. Stir in Avanzare av PLAT 2 (manufactured by Avanzare GmbH, La Rioja, Spain) until it reaches a weight of 30% by weight. Then, disperse the dispersion using an H7 ultrasonic finger. The device is set to 100% amplitude and 0.75 cycles. Disperse for 5 minutes first. Then, close the container and shake vigorously for 30 seconds. Repeat this procedure a total of three times.

[0142] Once a homogeneous dispersion is reached, stir it to prevent separation. This is done using a stirrer plate and a football-shaped stirrer bar at 600 rpm.

[0143] During step (c), the dispersion was stirred to prevent separation. The process parameters during step (c) were: Inlet temperature: 220℃, Outlet temperature: 95℃, Nozzle gas flow rate: 366 l / min Aspirator output 50% (about 20m 3 ( / h), pump output 30% (approx. 8ml / min) That was indeed the case.

[0144] The resulting graphene superparticles were formed in the form of loose aggregates held together solely by van der Waals forces, and therefore could be broken under moderate shear forces. Such forces were generated, for example, in the cyclone of a spray dryer. Therefore, the graphene superparticles were withdrawn from directly below the spray chamber, and any particles downstream of the cyclone were discarded. These consisted only of fragments of graphene superparticles.

[0145] Figure 15 shows a SEM image of graphene superparticles.

[0146] Figure 16 shows that there is a wide range of particle sizes that do not adversely affect the processability of graphene material.

[0147] The particle size distribution of graphene superparticles manufactured according to the present invention is evident from Figures 11 and 12. The graphene superparticles have a diameter of an order of magnitude greater than 90 μm.

[0148] The particle is 37.3m 2 It has a BET surface area of ​​ / g.

[0149] Example 4: Avanzare av PLAT 2 and AEROXIDE® Alu 65 The graphene material used was Avanzare av PLAT 2 (manufactured by Avanzare, located in La Rioja, Spain).

[0150] Figure 13 shows an SEM image of graphene material. It is in the form of platelets, which are partially in the form of aggregates.

[0151] Figure 14 shows the corresponding particle size distribution.

[0152] Here, the following characteristic diameter is measured: d 10 0.9 μm, d 50 2.7 μm, d 90 13 μm.

[0153] Manufacturing of dispersions: A dispersion consisting of water, Avanzare av PLAT 2 (manufactured by Avanzare, located in La Rioja, Spain), and AEROXIDE® Alu 65 (manufactured by Evonik, located in Essen, Germany) is prepared as follows.

[0154] Dissolve the appropriate additive, TEGOMER® DA 850 (manufactured by Evonik GmbH, Essen, Germany), in water. Stir the First Graphene pure graph 20 until it reaches a weight of 30% by weight. Then, disperse the dispersion using an H7 ultrasonic finger. The device is set to 100% amplitude and 0.75 cycles. Disperse for 5 minutes first. Then, close the container and shake vigorously for 30 seconds. Repeat this procedure a total of three times.

[0155] Once a homogeneous dispersion is reached, stir it to prevent separation. This is done using a stirrer plate and a football-shaped stirrer bar at 600 rpm.

[0156] During step (c), the dispersion was stirred to prevent separation. The process parameters during step (c) were: Inlet temperature: 220℃, Outlet temperature: 95℃, Nozzle gas flow rate: 366 l / min Aspirator output 50% (about 20m 3 ( / h), pump output 30% (approx. 8ml / min) That was indeed the case.

[0157] The resulting graphene superparticles were formed in the form of loose aggregates held together solely by van der Waals forces, and therefore could be broken under moderate shear forces. Such forces were generated, for example, in the cyclone of a spray dryer. Therefore, the graphene superparticles were withdrawn from directly below the spray chamber, and any particles downstream of the cyclone were discarded. These consisted only of fragments of graphene superparticles.

[0158] Figure 17 shows a SEM image of graphene superparticles.

[0159] Figure 18 shows that there is a wide range of particle sizes that do not adversely affect the processability of graphene material.

[0160] The particle size distribution of graphene superparticles manufactured according to the present invention is evident from Figures 17 and 18. The graphene superparticles have a diameter of an order of magnitude greater than 90 μm.

[0161] The particle is 137.1m 2 It has a BET surface area of ​​ / g.

[0162] Example 5: Fluidity and dust content liquidity To quantitatively evaluate the fluidity of the graphene superparticles obtained in Example 1, the Hausner coefficient in accordance with ASTM 527, the dynamic avalanche angle, and the inclination angle in accordance with ISO 4324 were measured in each case.

[0163] The compaction density and bulk density related to the Hausner coefficient from Example 1 are shown in Table 3.

[0164] [Table 3]

[0165] When comparing the bulk density and compaction density of graphene superparticles produced according to the present invention with those of graphene-based materials, a clear increase was observed after spray drying.

[0166] In the case of graphene superparticles manufactured according to the present invention, it was found that the Hausner coefficient was lower and therefore the compatibility was lower.

[0167] Table 4 shows the inclination angle and dynamic avalanche angle of the graphene material used, in accordance with ISO 4324, compared with the values ​​for graphene superparticles.

[0168] [Table 4]

[0169] Due to the poor flow properties and significant fouling observed within the chamber, optical evaluation of the dynamic avalanche angle was not possible with graphene-based materials.

[0170] Therefore, it has become clear that graphene superparticles with better fluidity can be obtained by the method according to the present invention.

[0171] Determination of dust levels in accordance with DIN 55992-1 (June 2006 edition) In the context of this invention, the dust level is determined by a Heubach dust meter Type I dust generating device using a rotation method in accordance with DIN 55992 (June 2006 edition), as schematically shown in Figure 1. The details of the structure of this device are known to those skilled in the art.

[0172] For determination, 5 g of powder material was introduced into the dust meter chamber as a sample weight. The chamber was equipped with a paddle, which was used to continuously move the powder. The filter unit was weighed before and after the measurement. A constant gas flow rate of 20 l / min was applied to the entire powder. The chamber rotated at 30 revolutions per minute.

[0173] The dust value is calculated from the ratio of the mass of powder in the filter after the experiment to the mass of powder initially loaded into the chamber, i.e., the mass of dust released from the sample weight by a standard dust generating device.

[0174] The mass of dust released from the sample weight by a standard dust generating device is based on the sample weight and is reported as a weight percentage.

[0175] Table 5 shows the results of the measured dust levels.

[0176] [Table 5]

[0177] The graphene superparticles according to the present invention were found to have a lower dust value than untreated graphene-based materials. In the case of the particles according to the present invention, the stability of the graphene superparticles was improved, particularly on the surface, because the gaps between smaller particles in the graphene material used were filled.

[0178] Example 4: Effects of using aluminum oxide Graphene superparticles were prepared according to Example 2, except that different commercially available aluminum oxides were used. Measurements of compaction density, bulk density, Hausner coefficient, inclination angle, and dynamic avalanche angle of the functionalized superparticles according to Example 3+5, performed according to Example 2+4, did not show significant differences from the measurements of the graphene superparticles according to Example 2.

[0179] Example 5: Thermal conductivity and electrical insulation The graphene superparticles of the present invention according to Example 2, as well as the First Graphene pure graph 20 and aluminum oxide particles used in Example 2, were each introduced separately into an epoxy resin matrix in an amount of 20 wt%. The resulting products were tested for thermal conductivity and electrical insulation using the test methods described above. These results are shown in Figure 19. As can be seen from this figure, the superparticles according to the present invention had a sheet resistance several orders of magnitude higher than uncoated First Graphene pure graph 20, while no significant decrease in thermal conductivity was observed. A clear improvement in thermal conductivity was achieved compared to pure aluminum oxide. Furthermore, surprisingly, an even greater improvement in electrical insulation was found compared to pure aluminum oxide.

[0180] Therefore, the superparticles produced by the method according to the present invention have improved electrical insulation properties without lowering their thermal conductivity. [Brief explanation of the drawing]

[0181] [Figure 1] This figure shows a Heubach dust meter Type I dust generating device. [Figure 2] This is a schematic diagram of a preferred method according to the present invention. [Figure 3] This is a schematic diagram of the hypothetical formation of graphene superparticles F, J, and P according to the present invention after the implementation of step c. [Figure 4a] This is a schematic diagram illustrating the principle of the Revolution Powder Analyzer's functionality. [Figure 4b] This is a schematic diagram of a spray dryer that is preferred for use. [Figure 5] This is a diagram showing the starting materials for Gamor GO. [Figure 6] This figure shows the particle size distribution of Gamor GO starting material measured in water, with agitator speed 6, ultrasonic waves for 1 minute, and circulation speed 6. [Figure 7] This diagram shows spray-dried Gamor GO graphene superparticles. [Figure 8] This figure shows the particle size distribution of Gamor GO ultrafine particles measured in water with agitator speed 6, ultrasonic waves for 1 minute, and circulation speed 6. [Figure 9] First Graphene pure graph 20 This is a diagram showing the starting materials. [Figure 10] This figure shows the particle size distribution of the starting material in First Graphene pure graph 20, measured in water with agitator speed 6, ultrasonic waves for 1 minute, and circulation speed 6. [Figure 11] This figure shows 60 wt% spray-dried First Graphene pure graph 20 + 40 wt% AEROXIDE® Alu 65 graphene superparticles. [Figure 12] This figure shows the particle size distribution of 60 wt% First Graphene pure graph and 20 + 40 wt% AEROXIDE® Alu 65 graphene superparticles. [Figure 13] This is a diagram showing the starting materials for Avanzare av PLAT 2. [Figure 14] This is a diagram showing the particle size distribution of the starting materials for Avanzare av PLAT 2. [Figure 15] This diagram shows spray-dried Avanzare av PLAT 2 superparticles. [Figure 16] This is a diagram showing the particle size distribution of Avanzare av PLAT 2 superparticles. [Figure 17] This figure shows 60 wt% spray-dried Avanzare av PLAT 2 + 40 wt% AEROXIDE® Alu 65 graphene superparticles. [Figure 18] This figure shows the particle size distribution of 60 wt% spray-dried Avanzare av PLAT 2 + 40 wt% AEROXIDE® Alu 65 graphene superparticles. [Figure 19] This figure compares the sheet resistance of the graphene superparticles (black squares) of the present invention with that of pure First Graphene pure graph 20 (black diamonds) and pure aluminum oxide (black triangles), with respect to thermal conductivity. In both cases, the figure represents 20% by weight of particles in epoxy resin.

Claims

1. A method for producing graphene superparticles, (a) Particle size diameter d from 0.5 μm to 100 μm ５０ Mix at least one graphene material having a solvent, (b) Add to the dispersion obtained in step (a) Based on the mass of the graphene material used, 0 to 100% by weight, preferably 0.1 to 100% by weight, of a dispersion aid, wetting aid, emulsifier, and / or defoaming agent. Add, after that, (c) At least partially remove the solvent from the dispersion obtained in step (b) by spray drying, Obtaining graphene superparticles method.

2. In step (a), graphene material or SiO ２ , aluminum oxide, TiO ２ , MgO, ZnO, SbO, organic fillers, or polymers, or at least one further material (a1) selected from phosphates, chlorides, sulfates, or nitrites is used simultaneously or sequentially, and the particle size diameter d of the at least one further material ５０ The method according to claim 1, wherein the amount is at least one-tenth smaller.

3. The method according to claim 2, wherein the amounts of the graphene material and the further material (a1) in step (a) are 50:50, preferably 60:40, and more preferably 80:

20.

4. The spray drying in step (c) The dispersion obtained in step (b) is sprayed into an inert gas stream by a spray unit, and the solvent in the droplets formed by the spray is at least partially evaporated. The method according to any one of claims 1 to 3, including

5. The obtained graphene superparticles are deaggregated by the action of shear force in a matrix material, preferably a polymer, monomer, or solvent, thereby homogeneously dispersing the graphene particles in the matrix material. The method according to any one of claims 1 to 4, further comprising step (d) including the following:

6. The method according to any one of claims 1 to 5, wherein the solvent in step (a) is selected from water, distilled water, and alkanol, and is preferably ethanol.

7. In step (c), a diameter d of 1 μm to 500 μm, preferably 5 μm to 250 μm, more preferably 50 μm to 100 μm. ５０ The method according to any one of claims 1 to 6, wherein graphene superparticles having the property are obtained.

8. The method according to any one of claims 1 to 7, wherein the mass percentage of graphene in the dispersion used in step (b) is 5% by weight to 50% by weight.

9. The spraying unit in step (c) is a device having at least one two-phase nozzle, And / or the inert gas used is nitrogen, preferably dry nitrogen. The temperature of the inert gas flow is more preferably set to a range of 200°C to 400°C above the cooling limit temperature of the solvent, and even more preferably within the range of 220°C to 300°C. and / or the sprayed droplets have a size of 30 to 1000 μm, The method according to any one of claims 1 to 8.

10. In graphene superparticles obtained according to at least one of claims 1 to 9, An angle of repose in accordance with ISO 4324, of 50° to 20°, preferably 40° to 25°. Dynamic avalanche angle compliant with ISO 4324, 65° to 30° 1. Hausner coefficients in accordance with ASTM 527, ranging from 1.5 to 1. and / or Dust values ​​compliant with DIN 55992 Type I, ranging from 10 to 0.

001. Graphene superparticles, characterized by the following features.

11. The graphene superparticle according to claim 10, wherein the amount of graphene in the graphene superparticle is at least 50% by weight.

12. - In particular, thermally conductive materials and thermally conductive adhesives in the fields of batteries, sensors, ICs, and LEDs, such as films, underflow materials, pourable electronic materials, materials with phase transitions, thermal pastes, sealing compounds, - Composite materials based on thermoplastic resins, thermosetting resins, and / or elastomers having increased electrical conductivity and / or thermal conductivity, or for EMI shielding, particularly in the field of housings for electrical components, motors, battery packs, and pipelines. - Coatings and varnishes having thermal conductivity and / or electrical conductivity, or for EMI shielding sector applications. - Thermally conductive and / or conductive oil, coolant, or ink Use of graphene superparticles obtained according to claim 10 or 11 or at least one of claims 1 to 9.

13. - A standard thermoplastic resin, preferably selected from PE, PP, PS, PVC, alpha-olefin, butadiene derivatives, and / or Vestenamer®. - Industrial thermoplastic resins, preferably PET, PMMA, PC, POM, PA, PBT, PEBA, TPU, PU, ​​and / or TPE, - High-performance thermoplastic resin, preferably PPS, PEEK, PES, PI, and / or PEI, - Pastes containing copolymers, elastomers, preferably silicones, more preferably room temperature crosslinked (RTV) silicones, high temperature crosslinked (HTV) silicones, liquid silicone rubber (LSR), heat crosslinked rubber (HCR), acrylates, and / or polysiloxanes and oligosiloxanes. - Polyurethane, rubber, preferably styrene-butadiene rubber (SVR), butadiene rubber (BR), and / or natural rubber, thermosetting resin, preferably polyurethane, polyester resin, phenolic resin, epoxy resin, acrylate resin, and / or silicone resin, - Solvents, preferably aprotic-nonpolar, aprotic-polar, and / or protic solvents. - Oil, preferably mineral oil, silicone oil, and / or process oil Use of graphene superparticles obtained according to claim 10 or 11 or at least one of claims 1 to 9.

14. Use of graphene superparticles obtained according to claim 10 or 11 or at least one of claims 1 to 9, preferably as an additive in compounders, extrusions, and injection moldings in the plastics processing industry.

Images