Graphene heating module and preparation method and curing system thereof

Abstract

The invention relates to a graphene heating module and a preparation method and curing system thereof, the graphene heating module comprises a carrier plate, a graphene heating film and a packaging protection layer, the carrier plate and the graphene heating film are stacked, and the packaging protection layer is arranged on the exposed outer surface of the graphene heating film; the graphene heating film comprises graphene and a doping agent; the packaging protection layer is made of a matrix inorganic substance and an expansion coefficient regulating agent; the relative difference percentage of the thermal expansion coefficients of the carrier plate and the packaging protection layer is less than or equal to 10%. According to the invention, the doping agent is doped to modify the graphene heating film, the electronic characteristics of the heating film are optimized to regulate and control the infrared radiation wavelength of the heating film, the thermal radiation performance of the heating film is improved, the thermal expansion coefficient of the packaging protection layer is regulated and controlled to tend to be consistent with that of the carrier plate, the requirements of the heating module for different slurries on the curing process are broadened, and the production cost is reduced. And the thermal field uniformity and the working stability of the heating module in the curing process are optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature control, and particularly to a graphene heating module, a preparation method thereof, and a curing system. Background Art

[0002] High-precision curing technology has important applications in the fields of electronic ceramic components, electronic ceramic substrates, composite magnet films, high-temperature superconducting films, sensor induction films, energy device substrates and electrolyte films, precision electronic printing, water-based thick film casting and curing, etc. These fields have extremely high requirements for thermal uniformity during the curing process. Especially when dealing with the curing problem of high-thickness slurries, traditional curing methods often cannot ensure uniform heat distribution, resulting in unsatisfactory curing effects. Traditional curing systems mainly provide heat for materials through the method of circulating hot air. However, this method has problems such as large equipment volume, complex structure, and difficult temperature field regulation, and it is difficult to achieve precise temperature control. In the hot air circulation system, heat is transferred from the outside to the inside through heat conduction, and it is easy to generate obvious internal and external temperature gradients during the curing of high-thickness slurries, resulting in uneven thermal shrinkage stress, which in turn causes curing defects, and these defects are difficult to regulate.

[0003] In recent years, heating elements mainly composed of graphene heating films have received extensive attention in various fields. For example, CN111278176A discloses a graphene heating film and a graphene heating device. The graphene heating device includes a groove base, an upper cover, and a graphene heating film. The graphene heating film has considerable flexibility, toughness, and hardness, and has the functions of anti-bending, wear resistance, and appropriate stretching. The provided graphene heating device also has the advantages of convenient assembly, stable structure, and good electrical conductivity. CN221598155U discloses a graphene electric heater, including a base and an electric heating plate provided on the base; the electric heating plate includes an insulating and heat-conducting panel, a graphene electric heating film, and an insulating covering layer. The graphene electric heating film is provided on the inner surface of the insulating and heat-conducting panel and is completely covered by the insulating covering layer; conductive electrodes are respectively provided at both ends of the graphene electric heating film, and the insulating covering layer is provided with a window exposing the conductive electrodes, and the conductive electrodes are electrically connected to the power connection terminals provided on the base through the window. The graphene electric heater in this prior art has the advantages of good heating effect, high stability, and easy installation.

[0004] Due to the excellent thermal conductivity and heating efficiency of graphene, it is considered to have great potential in improving the thermal uniformity during the curing process. However, graphene heating films still face some challenges when applied to curing systems. Although graphene heating films usually adopt coating protection, the density and stability of the coatings are relatively low. Especially in an environment with high volatile organic compounds (VOCs), it is difficult for the protective film to completely prevent the erosion of the external environment. These environmental factors may penetrate through the coating, affecting the carrier concentration of graphene, resulting in fluctuations in conductivity, and further affecting thermal uniformity and heating efficiency, reducing the curing quality. After long-term use, the graphene heating film may be oxidized, reducing its conductivity and causing unstable temperature control. At the same time, there is also a certain degree of non-uniformity in the temperature distribution of the graphene heating film, and performance degradation and local overheating problems may occur under long-term high-temperature operation, which poses a threat to the stability of the high-precision curing process. More critically, existing curing systems have not fully utilized the infrared radiation characteristics of graphene heating films, do not have effective wavelength regulation means, and still rely on heat conduction for curing, resulting in inaccurate thermal energy distribution and unable to fully exert the advantages of infrared radiation in improving curing efficiency and thermal uniformity, thus limiting its application effect in the field of high-precision curing.

[0005] Therefore, how to regulate the effective wavelength of the graphene heating film and optimize the thermal uniformity and working stability of the graphene heating film during the curing process are the technical problems that need to be solved urgently at present. Summary of the Invention

[0006] To solve the above technical problems, the purpose of the present invention is to provide a graphene heating module, its preparation method, and a curing system. The present invention modifies the graphene heating film by doping with a dopant, optimizes the electronic properties of the heating film and regulates its infrared radiation wavelength, improves the thermal radiation performance of the heating film itself, and then regulates the thermal expansion coefficient of the encapsulation protective layer to be consistent with that of the carrier plate, while broadening the requirements of the formed graphene heating module for different slurry curing processes and optimizing the thermal field uniformity of the graphene heating module during the curing process, improving the working stability of the heating module.

[0007] To achieve this purpose, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a graphene heating module, which includes a carrier board, a graphene heating film, and a packaging protective layer. The carrier board and the graphene heating film are stacked, and the packaging protective layer is disposed on the exposed outer surface of the graphene heating film; the graphene heating film includes graphene and a dopant; the material of the packaging protective layer includes a matrix inorganic substance and a coefficient of thermal expansion regulator; below 800 °C, the relative difference percentage of the coefficient of thermal expansion between the carrier board and the packaging protective layer ≤ 10%, such as 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2% or 1%, etc.

[0009] In the present invention, "the packaging protective layer is disposed on the exposed outer surface of the graphene heating film" means that the packaging protective layer is disposed on the surface of the graphene heating film away from the carrier board and on all sides of the graphene heating film. The packaging protective layer and the carrier board together encapsulate and protect the graphene heating film.

[0010] In the present invention, "the relative difference percentage of the coefficient of thermal expansion between the carrier board and the packaging protective layer" refers to the percentage of the ratio of the absolute value of the difference between the coefficient of thermal expansion of the carrier board and the coefficient of thermal expansion of the packaging protective layer to the coefficient of thermal expansion of the carrier board.

[0011] In the present invention, the "coefficient of thermal expansion" refers to the linear expansion coefficient of the carrier board and the packaging protective layer below 800 °C, such as 50 °C, 100 °C, 150 °C, 200 °C, 250 °C, 300 °C, 350 °C, 400 °C, 450 °C, 500 °C, 550 °C, 600 °C, 650 °C, 700 °C, 750 °C or 800 °C, etc.

[0012] In the graphene heating module provided by the present invention, chemical doping modification is performed on the heating film through doping with a dopant to change the electron cloud density of the graphene heating film, optimize the electronic properties of graphene to regulate its emission wavelength, improve the thermal radiation performance of the graphene heating film, so that it can adapt to the specific wavelength requirements of different curing materials. Utilizing the matching characteristics of the infrared band with the characteristic vibration peaks of the molecular bonds and functional groups of the material to be cured, the graphene heating film can effectively shorten the curing time and reduce the curing temperature for curing the material to be cured by the graphene heating module under the combined action of thermal radiation and heat conduction, so as to improve the curing efficiency and at the same time improve the curing quality when the heating module is applied to the curing system. As a result, the graphene heating module provided by the present invention can be applicable to the curing process requirements of various slurries with various high thicknesses and various compositions, and achieve more excellent curing efficiency and curing quality.

[0013] The setting of the carrier plate provides a stable substrate for the graphene heating film, preventing the deformation or fracture of the graphene heating film, and at the same time quickly transferring the heat and infrared radiation generated by the graphene heating film to the outside, ensuring the uniform diffusion of temperature. The exposed outer surface of the graphene heating film is encapsulated in cooperation with the carrier plate by an encapsulation protective layer. The encapsulation protective layer precisely regulates its own thermal expansion coefficient through the combination of matrix inorganic substances and thermal expansion coefficient regulators, making the expansion coefficient of the encapsulation protective layer tend to be consistent with that of the carrier plate. Specifically, the relative difference percentage of the thermal expansion coefficients of the carrier plate and the encapsulation protective layer is within a specific range, which can reduce the generation of microdefects such as cracks and pores caused by uneven thermal stress distribution during the curing process of the encapsulation protective layer, effectively improving the protection effect of the encapsulation protective layer on the graphene heating film, and thus being able to effectively shield the pollution, oxidation or moisture erosion behavior of the external environment on the graphene heating film during the use of the graphene heating module, and further improving the thermal uniformity and long-term working stability of the graphene heating module.

[0014] Preferably, based on the total mass of the graphene heating film being 100 wt%, the doping amount of the dopant is 0.01 - 0.1 wt%, such as 0.01 wt%, 0.02 wt%, 0.03 wt%, 0.04 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.09 wt% or 0.1 wt%, etc.

[0015] The present invention further regulates the doping amount of the dopant in the graphene heating film, which can further improve the thermal radiation performance of the graphene heating film and avoid the influence of too high or too low doping amount on the performance of the graphene heating film.

[0016] Preferably, the dopant includes any one or a combination of at least two of metals, non-metals, organic small molecules, conductive polymers or low-dimensional materials.

[0017] Preferably, among the dopants, the metal includes any one or a combination of at least two of iron, cobalt, nickel, lithium or sodium.

[0018] Preferably, among the dopants, the non-metal includes any one or a combination of at least two of nitrogen, boron, sulfur, phosphorus or fluorine.

[0019] Preferably, among the dopants, the organic small molecule includes 7,7,8,8-tetracyanoquinodimethane and / or tetrathiafulvalene.

[0020] Preferably, among the dopants, the conductive polymer includes polyaniline and / or polypyrrole.

[0021] Preferably, among the dopants, the low-dimensional material includes any one or a combination of at least two of carbon nanotubes, quantum dots or MXene.

[0022] Preferably, below 800 °C, the percentage of the relative difference in the coefficient of thermal expansion between the carrier plate and the encapsulation protective layer ≤ 5%, such as 5%, 4%, 3%, 2%, or 1%, etc. The temperature "below 800 °C" is, for example, 50 °C, 100 °C, 150 °C, 200 °C, 250 °C, 300 °C, 350 °C, 400 °C, 450 °C, 500 °C, 550 °C, 600 °C, 650 °C, 700 °C, 750 °C, or 800 °C, etc.

[0023] Preferably, in the encapsulation protective layer, based on the total mass of the matrix inorganic substance and the coefficient of thermal expansion regulator being 100 wt%, the mass proportion of the coefficient of thermal expansion regulator is 0 - 20 wt%, and does not include 0, such as 0.1 wt%, 0.5 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, or 20 wt%, etc.

[0024] By regulating the contents of the matrix inorganic substance and the coefficient of thermal expansion regulator in the encapsulation protective layer, and in combination with the selection of the types of the matrix inorganic substance and the coefficient of thermal expansion regulator, the present invention can more precisely regulate the coefficient of thermal expansion of the encapsulation protective layer, so that the coefficients of thermal expansion of the carrier plate for encapsulating and protecting the graphene heating film and the encapsulation protective layer tend to be consistent, thereby reducing micro-defect phenomena such as cracks or pores generated in the encapsulation protective layer due to uneven thermal stress distribution, and avoiding the influence on the quality of the encapsulation protective layer caused by too high or too low content of the coefficient of thermal expansion regulator.

[0025] Preferably, the matrix inorganic substance includes any one or a combination of at least two of oxides, nitrides, or carbides.

[0026] Preferably, the oxide includes any one or a combination of at least two of aluminum oxide, zirconium oxide, or magnesium oxide.

[0027] Preferably, the nitride includes any one or a combination of at least two of aluminum nitride, silicon nitride, or boron nitride.

[0028] Preferably, the carbide includes any one or a combination of at least two of silicon carbide, boron carbide, or zirconium carbide.

[0029] Preferably, the coefficient of thermal expansion regulator includes NaAlSi 3 O 8 、CaMoO 4 、B 2 O 3 、SiO2 or ZrW 2 O 8 or any combination of at least two of them.

[0030] In the present invention, a variety of thermal expansion coefficient regulators are selected for the thermal expansion coefficient regulator, aiming to precisely regulate the thermal expansion coefficient of the encapsulation protective layer by matching different matrix inorganic substances with thermal expansion coefficient regulators having different thermal expansion coefficients, so that the relative difference percentage between the thermal expansion coefficient of the encapsulation protective layer and the thermal expansion coefficient of the carrier plate is within a specific range.

[0031] Preferably, a first conductive electrode and a second conductive electrode are further provided on the surface of the graphene heating film away from the carrier plate side, and the first conductive electrode and the second conductive electrode are respectively located at opposite ends of the surface of the graphene heating film.

[0032] Preferably, the encapsulation protective layer covers the exposed outer surface of the graphene heating film outside the regions where the first conductive electrode and the second conductive electrode are located, and the encapsulation protective layer is in direct contact connection with both the first conductive electrode and the second conductive electrode.

[0033] Preferably, the thickness of the carrier plate is 2 - 4 mm, such as 2 mm, 2.25 mm, 2.5 mm, 2.75 mm, 3 mm, 3.25 mm, 3.5 mm, 3.75 mm or 4 mm, etc.

[0034] Preferably, the material of the carrier plate includes any one or a combination of at least two of quartz glass, borosilicate glass, aluminosilicate glass or high - alumina glass.

[0035] Preferably, the thickness of the graphene heating film is 200 - 450 μm, such as 200 μm, 225 μm, 250 μm, 275 μm, 300 μm, 325 μm, 350 μm, 375 μm, 400 μm, 425 μm or 450 μm, etc.

[0036] Preferably, the thickness of the encapsulation protective layer on the surface of the graphene heating film away from the carrier plate side is 400 - 900 μm, such as 400 μm, 450 μm, 500 μm, 550 μm, 600 μm, 650 μm, 700 μm, 750 μm, 800 μm, 850 μm or 900 μm, etc.

[0037] The present invention does not specifically limit the thickness of the encapsulation protective layer on the side of the graphene heating film, that is, it is only necessary to cooperate with the carrier plate to encapsulate and protect the graphene heating film.

[0038] Preferably, the materials of the first conductive electrode and the second conductive electrode are independently selected from any one or a combination of at least two of copper, aluminum, silver, gold, or copper plated with silver on the surface, preferably silver or copper.

[0039] Preferably, the thicknesses of the first conductive electrode and the second conductive electrode are independently selected from below 300 μm, such as 300 μm, 280 μm, 260 μm, 240 μm, 220 μm, or 200 μm, etc.

[0040] Preferably, the operating temperature of the graphene heating module is 0 - 800 °C, such as 0 °C, 10 °C, 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, or 800 °C, etc.

[0041] Preferably, the tolerance temperature of the graphene heating film is 0 - 1800 °C, such as 0 °C, 10 °C, 100 °C, 200 °C, 400 °C, 600 °C, 800 °C, 1000 °C, 1200 °C, 1400 °C, 1600 °C, or 1800 °C, etc.

[0042] In a second aspect, the present invention provides a preparation method of the graphene heating module according to the first aspect, and the preparation method includes the following steps:

[0043] A graphene heating film made of doped graphene is provided on a carrier plate, and an encapsulation protection layer is prepared on the exposed outer surface of the graphene heating film to obtain the graphene heating module;

[0044] The material of the encapsulation protection layer includes matrix inorganic substances and a thermal expansion coefficient regulator; below 800 °C, the relative difference percentage of the thermal expansion coefficients of the carrier plate and the encapsulation protection layer ≤ 10%.

[0045] The preparation method of the graphene heating module provided by the present invention directly provides a graphene heating film made of doped graphene on a carrier plate, and sets an encapsulation protection layer with a specific composition on the graphene heating film. The adopted preparation process is simple and low-cost, and is suitable for the industrial production of graphene heating modules. Through the doping modification of the graphene heating film by the dopant, the electronic properties of the heating film are optimized to regulate its infrared radiation wavelength, improving the thermal radiation performance of the graphene heating film, so that the obtained graphene heating module can meet the requirements of different materials to be cured; in addition, through the encapsulation protection layer composed of matrix inorganic substances and a thermal expansion coefficient regulator, the thermal expansion coefficient of the encapsulation protection layer is accurately regulated, making the thermal expansion coefficient of the encapsulation protection layer tend to be consistent with that of the carrier plate, reducing the damage of thermal stress to the encapsulation protection layer, effectively shielding the influence of the external environment on the graphene heating film, and improving the thermal uniformity and long-term working stability of the graphene heating film module.

[0046] Preferably, the dopant includes any one or a combination of at least two of metals, non-metals, organic small molecules, conductive polymers, or low-dimensional materials.

[0047] Preferably, the method of modifying the graphene with the dopant includes any one or a combination of at least two of chemical vapor deposition, hydrothermal method, solid-phase synthesis method, or electrochemical method, and is used for preparing a graphene heating film.

[0048] In the present invention, the method of modifying graphene with the dopant adopts the above-mentioned multiple methods. The specific processes of the above methods are not specifically limited in the present invention, and the specific processes of the above methods that can be obtained by those skilled in the art within a reasonable range are applicable to the present invention.

[0049] Exemplarily, the specific process of doping and modifying graphene by chemical vapor deposition includes: depositing the dopant on the surface of graphene by chemical vapor deposition to obtain modified graphene, which is used to form a graphene heating film.

[0050] Exemplarily, the specific process of doping and modifying graphene by the hydrothermal method includes: mixing and dispersing a formulated amount of the dopant and graphene dispersion in the presence of an antioxidant, then placing it in a hydrothermal reaction kettle for hydrothermal reaction, centrifuging and drying to obtain modified graphene, which is used to form a graphene heating film.

[0051] Exemplarily, the specific process of doping and modifying graphene by the solid-phase synthesis method includes: performing solid-phase mixing of a formulated amount of the dopant and graphene powder, and then performing heat treatment in an inert atmosphere to obtain a mixed powder, and preparing modified graphene, which is used to form a graphene heating film.

[0052] Exemplarily, the specific process of doping and modifying graphene by the electrochemical method includes: dispersing graphene in an electrolyte containing the dopant, and under a constant voltage or pulse mode, the dopant is embedded into the graphene interlayer or surface through electrochemical reduction / oxidation, removing the electrode material, ultrasonic exfoliation and drying to obtain the modified graphene, which is used to form a graphene heating film.

[0053] Preferably, after modifying the graphene with the dopant, it further includes mixing the modified graphene with a film-forming agent and a solvent, then coating it on the carrier plate, and curing to obtain the graphene heating film.

[0054] The solvent and film-forming agent introduced in the process of preparing the graphene heating film in the present invention will volatilize during the subsequent curing process, and a graphene heating film doped and modified with a dopant is prepared.

[0055] Preferably, in the process of preparing the graphene heating film, the mass ratio of the modified graphene, the film-forming agent and the solvent is (50 - 80):(10 - 40):(5 - 10); wherein, the selection range of the mass fraction of the modified graphene is "50 - 80", such as 50, 55, 60, 65, 70, 75 or 80, etc.; the selection range of the mass fraction of the film-forming agent is "10 - 40", such as 10, 15, 20, 25, 30, 35 or 40, etc.; the selection range of the mass fraction of the solvent is "5 - 10", such as 5, 6, 7, 8, 9 or 10, etc.

[0056] Preferably, in the process of preparing the graphene heating film, the film-forming agent includes any one or a combination of at least two of epoxy resin, silicone, acrylic acid or polyurethane.

[0057] Preferably, in the process of preparing the graphene heating film, the solvent includes any one or a combination of at least two of ethyl acetate, butyl acetate, propylene glycol acetate, propylene glycol methyl ether acetate, toluene, xylene, acetone, dichloromethane, ethylene glycol methyl ether or ethylene glycol ethyl ether.

[0058] Preferably, in the process of preparing the graphene heating film, the curing temperature is 100 - 400 °C, such as 100 °C, 150 °C, 200 °C, 250 °C, 300 °C, 350 °C or 400 °C, etc.

[0059] Preferably, the specific preparation process of the encapsulation protection layer includes: mixing the matrix inorganic substance and the coefficient of thermal expansion regulator according to the formula amount, then adding a solvent and a film-forming agent and mixing evenly to obtain a precursor slurry of the encapsulation protection layer, coating the precursor slurry of the encapsulation protection layer on the exposed outer surface of the graphene heating film, and then curing to obtain the encapsulation protection layer.

[0060] In the present invention, the solvent and the film-forming agent introduced into the precursor slurry in the process of preparing the encapsulation protection layer will volatilize in the subsequent curing process of the encapsulation protection layer, and an encapsulation protection layer containing a matrix inorganic substance and a coefficient of thermal expansion regulator is prepared.

[0061] Preferably, in the process of preparing the encapsulation protection layer, the film-forming agent includes acrylic acid and / or polyurethane.

[0062] Preferably, in the process of preparing the encapsulation protection layer, the curing temperature is 100 - 400 °C, such as 100 °C, 150 °C, 200 °C, 250 °C, 300 °C, 350 °C or 400 °C, etc.

[0063] Preferably, in the preparation process of the encapsulation protective layer precursor slurry, the mass ratio of the total mass of the matrix inorganic substance and the coefficient of thermal expansion regulator to the mass of the solvent is (1 - 5):1, such as 1:1, 2:1, 3:1, 4:1 or 5:1, etc.

[0064] Preferably, in the preparation process of the encapsulation protective layer precursor slurry, the mass ratio of the total mass of the matrix inorganic substance and the coefficient of thermal expansion regulator to the mass of the film-forming agent is (0.5 - 2):1, such as 0.5:1, 0.6:1, 0.8:1, 1.0:1, 1.2:1, 1.4:1, 1.6:1, 1.8:1 or 2.0:1, etc.

[0065] Preferably, in the process of preparing the encapsulation protective layer, the coating method includes any one of spraying, knife coating or screen printing.

[0066] Preferably, before preparing the encapsulation protective layer on the surface of the graphene heating film, a first conductive electrode and a second conductive electrode are further arranged on the surface of the graphene heating film on the side away from the carrier plate, and the first conductive electrode and the second conductive electrode are respectively arranged at the edges of the opposite ends on the surface of the graphene heating film.

[0067] Preferably, the setting methods of the first conductive electrode and the second conductive electrode are each independently selected from any one of welding, printing or crimping.

[0068] In a third aspect, the present invention provides a curing system for a graphene heating module, and the curing system includes the graphene heating module described in the first aspect, a temperature control module connected to the graphene heating module, and a control module connected to the temperature control module.

[0069] The curing system provided by the present invention uses the graphene heating module as the main heating element, which can significantly improve the curing efficiency and quality of the curing system, and ensure the thermal uniformity and working stability of the curing system; further, a temperature control module connected to the heating module is provided to monitor the surface temperature and the generated infrared radiation wavelength of the graphene heating module in real time, and dynamically regulate the power supply parameters of the graphene heating film, so as to further ensure the thermal field uniformity during the curing process and avoid local overheating or overcooling; the provided control module connected to the temperature control module can set the wavelength parameters, temperature range and power output of the curing process according to specific curing requirements, so as to achieve precise control of the parameters of the curing process. Through the mutual cooperation of the graphene heating module, the temperature control module and the control module, the present invention jointly improves the thermal field uniformity and long-term working stability of the curing process of the curing system, so that the curing system provided by the present invention can be widely applicable to the curing requirements of various compositions and thicknesses of slurries.

[0070] Preferably, the temperature control module includes a monitoring component, a temperature controller, and a data acquisition component.

[0071] Preferably, the temperature feedback accuracy of the temperature control module is 0.1 - 1 °C, such as 0.1 °C, 0.2 °C, 0.5 °C, 0.8 °C, or 1 °C, etc.

[0072] In the present invention, the temperature feedback accuracy of the temperature control module can reach 0.1 °C by means of a PID temperature controller and a programmable logic controller PLC.

[0073] Preferably, the operating temperature of the temperature control module is 0 - 800 °C, such as 0 °C, 10 °C, 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, or 800 °C, etc.

[0074] By further regulating the feedback accuracy and the operating temperature range of the temperature control module, the present invention can accurately perform thermal management and parameter control to ensure precise regulation of each parameter in the curing process of the graphene heating module for the material to be cured, further improving the curing uniformity and curing quality.

[0075] Preferably, the monitoring component includes a temperature sensor and an infrared probe.

[0076] Preferably, one end of the temperature sensor is disposed near the surface of the carrier plate in the graphene heating module on the side away from the graphene heating film, for monitoring the temperature of the graphene heating module; the other end of the temperature sensor is electrically connected to the data acquisition component, for real-time acquisition of the temperature of the graphene heating module.

[0077] Preferably, taking the direction perpendicular to the surface of the carrier plate as the vertical direction, the distance between the temperature sensor and the surface of the carrier plate in the vertical direction is 2 - 3 cm, such as 2.0 cm, 2.2 cm, 2.4 cm, 2.6 cm, 2.8 cm, or 3.0 cm, etc.

[0078] In the present invention, the temperature sensor can be fixed above the surface of the carrier plate through a bracket for monitoring the temperature generated by the graphene heating module.

[0079] Preferably, the infrared probe is a non-contact infrared probe, the non-contact infrared probe is disposed near the graphene heating module and connected to the data acquisition component, for real-time monitoring of the infrared radiation wavelength of the graphene heating module.

[0080] Preferably, the distance between the infrared probe and the center of the graphene heating film in the graphene heating module is 1.5 - 3 m, such as 1.5 m, 1.6 m, 1.8 m, 2.0 m, 2.2 m, 2.4 m, 2.6 m, 2.8 m, or 3.0 m, etc.

[0081] In the present invention, "the center of the graphene heating film" refers to the center of the graphene heating film in the direction perpendicular to the surface of the graphene heating film and in the direction parallel to the surface of the graphene heating film.

[0082] In the present invention, the specific position of the infrared probe is not specifically limited, as long as it can monitor the infrared radiation wavelength of the graphene heating module.

[0083] Preferably, the temperature controller is connected to the first conductive electrode and the second conductive electrode in the graphene heating module through a first circuit wire and a second circuit wire respectively.

[0084] Preferably, both the temperature controller and the data acquisition element are connected to the control module.

[0085] Preferably, the control module includes a programmable logic controller and a user interface.

[0086] In the present invention, the programmable logic controller and the user interface are integrated into a control module.

[0087] Preferably, the programmable logic controller is connected to both the data acquisition element and the temperature controller, and is used for analyzing and processing the processed data collected by the data acquisition element and setting the output parameters of the temperature controller.

[0088] In the curing system provided by the present invention, a programmable logic controller (PLC controller) is respectively connected to the data acquisition element and the temperature controller (PID) in the temperature control module. The PLC controller performs algorithm calculations on the data collected by the data acquisition element, executes logical judgments, sends control instructions to the PID for temperature control. The PID dynamically adjusts the system error calculation output value, and the output value of the control generates a PWM signal to control the output parameters of the conductive electrode in the graphene heating module, thereby controlling the curing parameters of the graphene heating module.

[0089] Preferably, the curing system further includes a power supply.

[0090] Preferably, the power supply is connected to the graphene heating module through the temperature controller.

[0091] It should be noted that the present invention does not specifically limit the number of graphene heating modules in the curing system, which can be 1, 2, 3, etc., and those skilled in the art can select according to needs.

[0092] Exemplarily, when the number of graphene heating modules in the curing system provided by the present invention is 1, the material to be cured is disposed on the surface of the carrier plate away from the graphene heating film for curing; when the number of graphene heating modules in the curing system provided by the present invention is 2, the graphene heating modules include a first graphene heating module and a second graphene heating module, which are placed in parallel. The surfaces of the carrier plates in the first graphene heating module away from the graphene heating film and the second graphene heating module away from the graphene heating film are relatively spaced apart. The material to be cured is placed in the spaced area where the carrier plates in the first graphene heating module and the second graphene heating module are relatively arranged for curing.

[0093] Compared with the prior art, the present invention has at least the following beneficial effects:

[0094] (1) The present invention modifies the graphene heating film by doping with a dopant, optimizes the electronic properties of the heating film, thereby regulating its infrared radiation wavelength, improving the thermal radiation performance of the heating film itself, and can effectively shorten the curing time of the graphene heating module for the material to be cured and reduce the curing temperature. At the same time, the curing quality when the heating module is applied in the curing system is improved, so that the graphene heating module provided by the present invention can be applied to the curing process requirements of various high-thickness and various-component slurries; on the other hand, the present invention regulates the composition of the encapsulation protective layer so that the thermal expansion coefficient of the encapsulation protective layer is consistent with that of the carrier plate, effectively improving the protection effect of the encapsulation protective layer on the graphene heating film, and thus can effectively shield the pollution, oxidation or moisture erosion behavior of the external environment on the graphene heating film during the use of the graphene heating module, and further improve the thermal uniformity and long-term working stability of the graphene heating module.

[0095] (2) The preparation method of the graphene heating module provided by the present invention directly sets a graphene heating film made of dopant-modified graphene on the carrier plate and sets an encapsulation protective layer with a specific composition on the graphene heating film. The preparation process adopted is simple and low-cost, and is suitable for the industrial production of graphene heating films.

[0096] (3) The curing system provided by the present invention uses the graphene heating module as the main heating element, which can significantly improve the curing efficiency and quality of the curing system, and ensure the thermal uniformity and working stability of the curing system; the temperature control module is used to monitor the surface temperature of the graphene heating module and the infrared radiation wavelength generated in real time, and dynamically regulate the power supply parameters of the graphene heating film, so as to further ensure the thermal field uniformity during the curing process; the control module can set the wavelength parameters, temperature range and power output of the curing process according to specific curing requirements, so as to achieve precise control of the parameters of the curing process. The graphene heating module, the temperature control module and the control module cooperate with each other to jointly improve the thermal field uniformity and long-term working stability of the curing process of the curing system, and are widely applicable to the curing requirements of slurries with various compositions and thicknesses. BRIEF DESCRIPTION OF THE DRAWINGS

[0097] Figure 1 is a schematic cross-sectional view of the front view structure of the graphene heating module provided by the present invention.

[0098] Figure 2 is a schematic bottom view structure diagram of the graphene heating module provided by the present invention.

[0099] Figure 3 is a schematic structural diagram of the curing systems provided by the application example and the comparative application example in the present invention.

[0100] Among them, 1, carrier plate; 2, graphene heating film; 3, first conductive electrode; 4, second conductive electrode; 5, encapsulation protection layer; 6, temperature sensor; 7, infrared probe; 8, temperature controller; 9, data acquisition element; 10, programmable logic controller; 11, user interface; 12, power supply; Ι, first circuit wire; Ⅱ, second circuit wire. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0101] The technical solutions of the present invention will be further described below with reference to the drawings and through specific embodiments. However, the following examples are only simple examples of the present invention and do not represent or limit the scope of the protection of the present invention. The scope of protection of the present invention is subject to the claims.

[0102] In the following examples, the temperature sensor used is a high-precision PT1000 platinum resistance temperature sensor of the Swiss Sensirion brand as the temperature detection element; the temperature controller is a CNi8DV54 PID temperature controller of the American Omega company; the data acquisition element is a PXI series data acquisition system of the American National Instruments; the non-contact infrared probe is a Raytek Marathon of the United States; the programmable logic controller is an S7-1200 series PLC of the German Siemens.

[0103] The coefficient of thermal expansion of each substance provided in the following embodiments is the coefficient of linear expansion. The coefficients of thermal expansion of the materials for the carrier board and the encapsulation protection layer only need to satisfy that the percentage of the relative difference in the coefficients of thermal expansion between the carrier board and the encapsulation protection layer is within a specific range under specific working temperature conditions.

[0104] Among them, the coefficient of thermal expansion of the borosilicate glass used in the following embodiments is ≈3.3×10 -6 / K below 800 °C, the coefficient of thermal expansion of silicon nitride is ≈3×10 -6 / K below 800 °C, the coefficient of thermal expansion of NaAlSi 3 O 8 is ≈5×10 -6 / K below 800 °C, the coefficient of thermal expansion of silicon carbide is ≈4×10 -6 / K below 800 °C, the coefficient of thermal expansion of SiO 2 is ≈0.5×10 -6 / K below 800 °C, the coefficient of thermal expansion of aluminosilicate glass is ≈4.5×10 -6 / K below 800 °C, and the coefficient of thermal expansion of aluminum nitride (AlN matrix) is ≈5×10 -6 / K.

[0105] Embodiment 1

[0106] This embodiment provides a graphene heating module. The schematic cross-sectional view of the specific front view structure is as shown in Figure 1 and the schematic bottom view structure is as shown in Figure 2 . It can be seen from the figure that the graphene heating module includes a carrier board 1, a graphene heating film 2 disposed on one surface of the carrier board 1. A first conductive electrode 3 and a second conductive electrode 4 are disposed on the surface of the graphene heating film 2 away from the carrier board 1. The first conductive electrode 3 and the second conductive electrode 4 are respectively located at the edges of the opposite ends on the surface of the graphene heating film 2. On the exposed outer surface of the graphene heating film 2, that is, on the surface and all side surfaces of the graphene heating film 2 away from the carrier board 1, an encapsulation protection layer 5 is further covered. The encapsulation protection layer 5 covers the exposed outer surface of the graphene heating film 2 outside the regions where the first conductive electrode 3 and the second conductive electrode 4 are located, and is in direct contact connection with the first conductive electrode 3 and the second conductive electrode 4.

[0107] Among them, the carrier board 1 is borosilicate glass with a thickness of 3 mm; the graphene heating film 2 includes a graphene film and cobalt metal uniformly doped in the graphene film. Based on the total mass of the graphene heating film 2 being 100 wt%, the doping amount of cobalt is 0.05 wt%. The thickness of the graphene heating film 2 is 350 μm, and the tolerance temperature of the graphene heating film 2 is 810 °C; the materials of the first conductive electrode 3 and the second conductive electrode 4 are both silver, and their thickness is 300 μm; the thickness of the encapsulation protection layer 5 on the surface of the graphene heating film 2 away from the carrier board 1 is 700 μm, which is composed of a silicon nitride matrix inorganic substance and a NaAlSi 3 O 8 thermal expansion coefficient regulator. Based on the total mass of silicon nitride and NaAlSi 3 O 8 being 100 wt%, the mass fraction of NaAlSi 3 O 8 is 14 wt%; below 800 °C, the relative difference percentage of the thermal expansion coefficients of the carrier board 1 and the encapsulation protection layer 5 is less than 5%.

[0108] The present invention also provides a preparation method of the above-mentioned graphene heating module, and the preparation method includes the following steps:

[0109] (1) Using chemical vapor deposition to dope a formulated amount of cobalt powder on graphene to obtain modified graphene, mixing the modified graphene with a polyurethane film-forming agent and an ethyl acetate solvent in a mass ratio of 60:30:10 to obtain a graphene mixed slurry, and then coating the graphene mixed slurry on the surface of one side of the borosilicate glass carrier board 1 and curing at 350 °C to form the graphene heating film 2 on the carrier board 1.

[0110] (2) Setting metal silver at the edges of the two opposite ends on the surface of the graphene heating film 2 away from the carrier board 1 by welding to obtain the first conductive electrode 3 and the second conductive electrode 4 respectively.

[0111] (3) Mixing silicon nitride and NaAlSi 3 O 8 according to the formulated amount, adding absolute ethanol and a film-forming agent acrylic acid and mixing evenly to obtain a mixed coating. Among them, the mass ratio of the total mass of silicon nitride and NaAlSi 3 O 8 to the mass of absolute ethanol is 2:1, and the total mass of silicon nitride and NaAlSi 3 O 8The mass ratio of the total mass to the film-forming agent is 1:1; the mixed coating is applied to the surface of the graphene heating film 2 on the side away from the carrier plate 1 and all sides of the graphene heating film 2 by the doctor blade method. The coating area on the surface of the graphene heating film 2 is set in the remaining area outside the areas where the first conductive electrode 3 and the second conductive electrode 4 are located, and is in direct contact with the first conductive electrode 3 and the second conductive electrode 4. Then, the coated component is cured at 350 °C to form an encapsulation protective layer 5 on the exposed outer surface of the graphene heating film 2, and a graphene heating module is prepared. By using a temperature sensor to detect the working temperature of the graphene heating module provided in this embodiment, it is obtained that the highest working temperature achieved by the graphene heating module provided in this embodiment is 800 °C.

[0112] Example 2

[0113] This embodiment provides a graphene heating module. The schematic cross-sectional view of the specific front view structure is as Figure 1 shown, and its schematic bottom view structure is as Figure 2 shown. It can be seen from the figure that the graphene heating module includes a carrier plate 1, a graphene heating film 2 provided on one surface of the carrier plate 1. A first conductive electrode 3 and a second conductive electrode 4 are provided on the surface of the graphene heating film 2 on the side away from the carrier plate 1. The first conductive electrode 3 and the second conductive electrode 4 are respectively located at the edges of the opposite ends on the surface of the graphene heating film 2. On the exposed outer surface of the graphene heating film 2, that is, on the surface of the graphene heating film 2 on the side away from the carrier plate 1 and all sides, there is also an encapsulation protective layer 5 covering the exposed outer surface of the graphene heating film 2 outside the areas where the first conductive electrode 3 and the second conductive electrode 4 are located, and is in direct contact connection with the first conductive electrode 3 and the second conductive electrode 4.

[0114] Among them, the carrier plate 1 is borosilicate glass with a thickness of 2 mm; the graphene heating film 2 includes graphene and doped carbon nanotubes doped in the graphene. Based on the total mass of the graphene heating film 2 being 100 wt%, the doping amount of the carbon nanotubes is 0.05 wt%. The thickness of the graphene heating film 2 is 450 μm, and the tolerance temperature of the graphene heating film 2 is 1120 °C; the materials of the first conductive electrode 3 and the second conductive electrode 4 are both copper, and their thickness is 240 μm. The thickness of the encapsulation protective layer 5 on the surface of the graphene heating film 2 on the side away from the carrier plate 1 is 900 μm, which is composed of a silicon carbide matrix inorganic substance and SiO 2 thermal expansion coefficient regulator. Based on the total mass of silicon carbide and SiO 2 being 100 wt%, the mass proportion of SiO 2 is 18 wt%; below 800 °C, the relative difference percentage of the thermal expansion coefficients of the carrier plate 1 and the encapsulation protective layer 5 is less than 5%.

[0115] The present invention also provides a preparation method of the above-mentioned graphene heating module, and the preparation method includes the following steps:

[0116] (1) The graphene heating film 2 is doped and modified with carbon nanotubes by using the solid-phase synthesis method. The specific process includes: dry ball-milling the formulated amount of carbon nanotubes and graphene powder to obtain a mixed powder, performing heat treatment at 500 °C for 1 h under argon protection to obtain modified graphene, mixing the modified graphene with an acrylic film-forming agent and toluene solvent in a mass ratio of 60:35:5 to obtain a graphene mixed slurry, and then coating the graphene mixed slurry on the surface of one side of the borosilicate glass carrier 1, and curing at 400 °C to form the graphene heating film 2 on the carrier 1.

[0117] (2) Metal copper is disposed at the edges of the two opposite ends on the surface of the graphene heating film 2 away from the carrier 1 by printing to obtain a first conductive electrode 3 and a second conductive electrode 4 respectively.

[0118] (3) Mix silicon carbide and SiO 2 in accordance with the formulated amount, then add absolute ethanol and a film-forming agent polyurethane and mix evenly to obtain a mixed coating. Among them, the mass ratio of the total mass of silicon carbide and SiO 2 to the mass of absolute ethanol is 1:1, and the mass ratio of the total mass of silicon carbide and SiO 2 to the mass of the film-forming agent is 2:1; the mixed coating is coated on the surface of the graphene heating film 2 away from the carrier 1 and on all sides of the graphene heating film 2 by spraying. The coating area on the surface of the graphene heating film 2 is set in the remaining area outside the areas where the first conductive electrode 3 and the second conductive electrode 4 are located, and is in direct contact with the first conductive electrode 3 and the second conductive electrode 4. Then, the coated component is cured at 300 °C to form a packaging and protective layer 5 on the exposed outer surface of the graphene heating film 2, and the graphene heating module is prepared. By using a temperature sensor to detect the working temperature of the graphene heating module provided in this embodiment, it is obtained that the highest working temperature achieved by the graphene heating module provided in this embodiment is 780 °C.

[0119] Example 3

[0120] This embodiment provides a graphene heating module, and the schematic cross-sectional view of the specific front view structure is as Figure 1 shown, and its schematic bottom view structure is as Figure 2As shown, it can be seen from the figure that the graphene heating module includes a carrier plate 1, a graphene heating film 2 disposed on one surface of the carrier plate 1. On the surface of the graphene heating film 2 away from the carrier plate 1, a first conductive electrode 3 and a second conductive electrode 4 are provided. The first conductive electrode 3 and the second conductive electrode 4 are respectively located at the edges of the opposite ends on the surface of the graphene heating film 2. On the exposed outer surface of the graphene heating film 2, that is, on the surface of the graphene heating film 2 away from the carrier plate 1 and all side surfaces, a packaging protective layer 5 is further covered. The packaging protective layer 5 covers the exposed outer surface of the graphene heating film 2 outside the regions where the first conductive electrode 3 and the second conductive electrode 4 are located, and is in direct contact connection with the first conductive electrode 3 and the second conductive electrode 4.

[0121] Among them, the carrier plate 1 is aluminosilicate glass with a thickness of 4 mm; the graphene heating film 2 includes graphene and nitrogen doped in the graphene. Based on the total mass of the graphene heating film 2 being 100 wt%, the doping amount of nitrogen is 0.05 wt%. The thickness of the graphene heating film 2 is 200 μm, and the tolerance temperature of the graphene heating film 2 is 1280 °C; the materials of the first conductive electrode 3 and the second conductive electrode 4 are both silver with a thickness of 200 μm; the thickness of the packaging protective layer 5 on the surface of the graphene heating film 2 away from the carrier plate 1 is 400 μm, and it is composed of an aluminum nitride matrix inorganic substance and an SiO 2 thermal expansion coefficient regulating agent. Based on the total mass of aluminum nitride and SiO 2 being 100 wt%, the mass proportion of SiO 2 is 10 wt%; below 800 °C, the relative difference percentage of the thermal expansion coefficients of the carrier plate 1 and the packaging protective layer 5 is less than 5%.

[0122] The present invention also provides a preparation method of the above-mentioned graphene heating module. The preparation method includes the following steps:

[0123] (1) The graphene heating film 2 is subjected to nitrogen doping modification by a hydrothermal method. The specific process includes: mixing a graphene dispersion solution with a concentration of 2 mg / mL, urea as a nitrogen source, and ascorbic acid as an antioxidant according to the formulated amounts. The mass ratio of the antioxidant to the graphene dispersion solution is 1:5. It is placed in a hydrothermal reaction kettle and subjected to hydrothermal reaction at 200 °C for 10 h, centrifuged, then washed with deionized water and dried with nitrogen, and then annealed at a temperature of 400 °C for 2 h under argon protection. The modified graphene, an acrylic film-forming agent, and an acetone solvent are mixed according to a mass ratio of 50:40:10 to obtain a graphene mixed slurry, and the modified graphene is obtained. Then, the graphene mixed slurry is coated on the surface of one side of the aluminosilicate glass carrier plate 1 and cured at 400 °C to form a nitrogen-doped graphene heating film 2 on the aluminosilicate glass carrier plate 1.

[0124] (2) On the surfaces at the opposite ends of the side of the graphene heating film 2 away from the carrier board 1, metal silver is provided by means of crimping to obtain a first conductive electrode 3 and a second conductive electrode 4 respectively.

[0125] (3) Mix aluminum nitride and SiO 2 in accordance with the formula amount, then add absolute ethanol and film-forming agent acrylic acid and mix evenly to obtain a mixed coating. Among them, the mass ratio of the total mass of aluminum nitride and SiO 2 to the mass of absolute ethanol is 5:1, and the mass ratio of the total mass of aluminum nitride and SiO 2 to the mass of the film-forming agent is 0.5:1; the mixed coating is coated on the surface of the side of the graphene heating film 2 away from the carrier board 1 and on all sides of the graphene heating film 2 by the doctor blade method. The coating area on the surface of the graphene heating film 2 is set in the area outside the areas where the first conductive electrode 3 and the second conductive electrode 4 are located, and is in direct contact with the first conductive electrode 3 and the second conductive electrode 4. Then, the coated component is cured at 400 °C to form a packaging and protective layer 5 on the exposed outer surface of the graphene heating film 2, and a graphene heating module is prepared. By using a temperature sensor to detect the working temperature of the graphene heating module provided in this embodiment, it is obtained that the highest working temperature achieved by the graphene heating module provided in this embodiment is 710 °C.

[0126] Example 4

[0127] The difference between this example and Example 1 is only that: in the graphene heating module provided in this example, based on the total mass of the graphene heating film 2 being 100 wt%, the doping amount of cobalt is 0.005 wt%. The rest are the same as those in Example 1.

[0128] Example 5

[0129] The difference between this example and Example 1 is only that: in the graphene heating module provided in this example, based on the total mass of the graphene heating film 2 being 100 wt%, the doping amount of cobalt is 0.15 wt%. The rest are the same as those in Example 1.

[0130] Example 6

[0131] The difference between this example and Example 1 is only that: in the graphene heating module provided in this example, the substance doped inside the graphene heating film 2 is copper oxide. The rest are the same as those in Example 1.

[0132] Comparative Example 1

[0133] The difference between this comparative example and Example 1 is only that: in the graphene heating module provided in this comparative example, the doping of cobalt is omitted on the graphene heating film 2. The rest are the same as those in Example 1.

[0134] Comparative Example 2

[0135] The difference between this comparative example and Example 2 is only that: in the graphene heating module provided in this comparative example, in the encapsulation protective layer 5, the coefficient of thermal expansion regulating agent SiO 2 is omitted, and the silicon nitride matrix inorganic substance is directly used as the encapsulation protective layer 5, and the relative difference percentage of the coefficient of thermal expansion between the carrier plate 1 and the encapsulation protective layer 5 is greater than 20%. The rest of the content is the same as that of Example 2. By using a temperature sensor to detect the working temperature of the graphene heating module provided in this comparative example, it is obtained that the highest working temperature achieved by the graphene heating module provided in this comparative example is 290 °C.

[0136] Comparative Example 3

[0137] The difference between this comparative example and Example 2 is only that: in the graphene heating module provided in this comparative example, taking the total mass of the silicon carbide matrix inorganic substance and the coefficient of thermal expansion regulating agent SiO 2 as 100 wt%, the mass ratio of the coefficient of thermal expansion regulating agent SiO 2 is 30 wt%, and the relative difference percentage of the coefficient of thermal expansion between the carrier plate 1 and the encapsulation protective layer 5 is greater than 10%. The rest of the content is the same as that of Example 2. By using a temperature sensor to detect the working temperature of the graphene heating module provided in this comparative example, it is obtained that the highest working temperature achieved by the graphene heating module provided in this comparative example is 360 °C.

[0138] Application Example 1

[0139] This application example provides a curing system, and its structural schematic diagram is as Figure 3 shown (in order to clearly show the connection relationship between the graphene heating module and the other components, Figure 3The graphene heating module in it is shown by a schematic cross-sectional view of the front view structure. The curing system includes the graphene heating module provided in Embodiment 1, a temperature control module connected to the graphene heating module, and a control module connected to the temperature control module. The number of graphene heating modules is 1. The temperature control module includes a temperature sensor 6, an infrared probe 7, a temperature controller 8, and a data acquisition element 9. One end of the temperature sensor 6 is arranged close to the surface of the carrier plate 1 in the graphene heating module on the side far from the graphene heating film 2, and the other end is connected to the data acquisition element 9 through a wire. Taking the direction perpendicular to the surface of the carrier plate 1 as the vertical direction, the distance between the temperature sensor 6 and the surface of the carrier plate 1 in the vertical direction is 2.5 cm. The infrared probe 7 is a non-contact infrared probe, which is arranged close to the graphene heating module and is 2 m away from the center of the graphene heating film 2 in the graphene heating module. The infrared probe 7 is also connected to the data acquisition element 9. The temperature controller 8 is connected to the first conductive electrode 3 and the second conductive electrode 4 in the graphene heating module through the first circuit wire Ι and the second circuit wire Ⅱ respectively. The first circuit wire Ι is the live wire, and the second circuit wire Ⅱ is the neutral wire. Both the temperature controller 8 and the data acquisition element 9 in the temperature control module are connected to the control module. The control module includes an integrated programmable logic controller 10 and a user interface 11. The programmable logic controller 10 is respectively connected to the data acquisition element 9 and the temperature controller 8. The curing system is also provided with a power supply 12, which is connected to the graphene heating module through the temperature controller 8.

[0140] Application Examples 2-6 and Comparative Application Examples 1-3

[0141] The differences between Application Examples 2-6 and Comparative Application Examples 1-3 and Application Example 1 are only that the graphene heating modules provided in Embodiment 1 used in the curing system are respectively replaced with the graphene heating modules provided in Embodiments 2-6 and Comparative Examples 1-3. The rest of the content is the same as that of Application Example 1.

[0142] The curing system provided by Application Examples 1-6 and Comparative Application Examples 1-3 was used for curing tests. The specific process of the test is as follows:

[0143] (1) Curing temperature and curing time: Place the silicon nitride slurry on the carrier plate of the curing system provided by Application Examples 1-6 and Comparative Application Examples 1-3, cure the silicon nitride slurry, and record the curing time required for the curing temperature of 65°C for the silicon nitride slurry cured by the curing systems provided by each of Application Examples 1-6 and Comparative Application Examples 1-3.

[0144] (2) Average temperature difference: Use a temperature sensor to measure the temperatures at three positions on the carrier board of the curing systems provided in Application Examples 1-6 and Comparative Application Examples 1-3 (the center of the carrier board and the center points at both ends along the length direction of the carrier board). Calculate the average temperature value of the three positions, and then calculate the absolute value of the temperature difference between the three positions and the average temperature value. Further calculate the average value of the absolute temperature differences, which is denoted as the average temperature difference.

[0145] (3) Working life: Set the curing systems provided in Application Examples 1-6 and Comparative Application Examples 1-3 to perform continuous high-temperature curing work at 300 °C. Use a temperature sensor to detect the temperature on the surface of the carrier board in the curing system at the same time gradient, and observe the morphology of the graphene heating module at the same time gradient. When any of the following situations occur: cracks or detachment in the encapsulation protective layer or the carrier board in the graphene heating module, or an increase of more than 5 °C compared to the initial average temperature difference value, then terminate the test and record the working life of the stable curing of the curing system.

[0146] The test results are shown in Table 1.

[0147] Table 1

[0148] Curing time (min) Average temperature difference (℃) Service life (years) Application Example 1 4.1 0.2 ＞2 Application Example 2 4.6 0.3 ＞2 Application Example 3 8.3 0.3 ＞2 Application Example 4 5.2 0.1 1-2 Application Example 5 6.1 0.5 1-2 Application Example 6 9.4 0.8 0.5-1 Comparative Application Example 1 56 0.3 / Comparative Application Example 2 14.2 1.6 ＜0.2 Comparative Application Example 3 9.7 1.0 ＜0.5

[0149] It can be seen from the test results in Table 1 that:

[0150] (1) It can be seen from Application Examples 1 to 3 that the present invention modifies the graphene heating film by doping with a dopant, optimizes the electronic properties of the heating film and regulates its infrared radiation wavelength, improves the thermal radiation performance of the heating film itself, and then regulates the thermal expansion coefficient of the encapsulation protective layer to be consistent with that of the carrier board. While broadening the requirements of the formed graphene heating module for different slurry curing processes and optimizing the thermal field uniformity during the curing process of the graphene heating module, the working stability of the heating module is improved.

[0151] (2) It can be seen by comparing Application Example 1 and Application Example 4 that if the doping amount of the dopant in the graphene heating film of the present invention is too low, it will lead to an increase in the curing time and a decrease in the curing efficiency of the curing system composed of the graphene heating module.

[0152] (3) It can be seen by comparing Application Example 1 and Application Example 5 that if the doping amount of the dopant in the graphene heating film of the present invention is too high, it will lead to an increase in the curing time and a decrease in the curing efficiency of the curing system composed of the graphene heating module, and the temperature difference on the surface of the carrier board in the graphene heating module increases, further affecting the curing effect and working stability when it is applied to the curing system.

[0153] (4) It can be seen from the comparison between Application Example 1 and Application Example 6 that if the doping substance inside the graphene heating film of the present invention is replaced with a metal oxide such as copper oxide, it will cause local heat accumulation on the graphene heating film, easily resulting in cracking or bubbling phenomena, reducing the working life of the graphene heating module, and thus leading to a decrease in the working life of the curing system composed of the graphene heating film.

[0154] (5) It can be seen from the comparison between Application Example 1 and Comparative Application Example 1 that if the graphene heating film of the present invention lacks the doping of the dopant and does not regulate the thermal radiation performance of the graphene heating film, it will greatly increase the curing time and reduce the curing efficiency of the graphene heating film.

[0155] (6) It can be seen from the comparison between Application Example 2 and Comparative Application Examples 2-3 that if the encapsulation protective layer of the present invention lacks the expansion coefficient regulator or the mass ratio of the expansion coefficient regulator is too high, resulting in too large a relative difference percentage of the thermal expansion coefficients of the encapsulation protective layer and the carrier plate, it will cause defects in the encapsulation protective layer under high-temperature curing conditions, making it difficult to completely prevent the erosion of the external environment on the graphene heating film, thereby affecting the long-term working stability of the curing system.

[0156] In summary, the present invention modifies the graphene heating film by doping with a dopant, optimizing the electronic properties of the heating film, thereby regulating its infrared radiation wavelength, improving the thermal radiation performance of the heating film itself, and being able to effectively shorten the curing time and curing temperature of the graphene heating module for the material to be cured, while improving the curing quality when the heating module is applied in the curing system, so that the graphene heating module provided by the present invention can be applicable to the curing process requirements of various slurries with various high thicknesses and various compositions; on the other hand, the present invention regulates the composition of the encapsulation protective layer to make the thermal expansion coefficient of the encapsulation protective layer tend to be consistent with that of the carrier plate, effectively improving the protection effect of the encapsulation protective layer on the graphene heating film, and thus being able to effectively shield the pollution, oxidation or moisture erosion behavior of the external environment on the graphene heating film during the use of the graphene heating module, and further improving the thermal uniformity and long-term working stability of the graphene heating module.

[0157] The applicant declares that the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by any person skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A graphene heating module, characterized in that: The graphene heating module comprises a carrier, a graphene heating film and a packaging protective layer, wherein the carrier and the graphene heating film are stacked, and the packaging protective layer is arranged on the exposed outer surface of the graphene heating film; the graphene heating film comprises graphene and a dopant; the material of the packaging protective layer comprises a matrix inorganic substance and an expansion coefficient regulating agent; Below 800° C., the relative difference percentage of the thermal expansion coefficients of the carrier board and the packaging protection layer is ≤10%.

2. The graphene heating module according to claim 1, characterized in that: Based on the total mass of the graphene heating film being 100wt%, the doping amount of the dopant is 0.01-0.1wt%; Preferably, the dopant comprises any one or a combination of at least two of metal, non-metal, organic small molecule, conductive polymer or low-dimensional material; Preferably, in the dopant, the metal includes any one or a combination of at least two of iron, cobalt, nickel, lithium or sodium; Preferably, in the dopant, the non-metal includes any one or a combination of at least two of nitrogen, boron, sulfur, phosphorus or fluorine; Preferably, in the dopant, the organic small molecule includes 7,7,8,8-tetracyano-p-benzoquinodimethane and / or tetrathiafulvalene; Preferably, in the dopant, the conductive polymer comprises polyaniline and / or polypyrrole; Preferably, in the dopant, the low-dimensional material includes any one of carbon nanotubes, quantum dots or MXene, or a combination of at least two of them.

3. The graphene heating module according to claim 1 or 2, characterized in that: Below 800° C., the relative difference percentage of the thermal expansion coefficients of the carrier and the packaging protection layer is ≤5%; Preferably, in the encapsulation protection layer, based on the total mass of the matrix inorganic substance and the expansion coefficient regulator being 100wt%, the mass proportion of the expansion coefficient regulator is 0-20wt%, excluding 0; Preferably, the matrix inorganic material comprises any one of oxides, nitrides or carbides or a combination of at least two thereof; Preferably, the oxide comprises any one of aluminum oxide, zirconium oxide or magnesium oxide, or a combination of at least two thereof; Preferably, the nitride comprises any one of aluminum nitride, silicon nitride or boron nitride, or a combination of at least two thereof; Preferably, the carbide comprises any one of silicon carbide, boron carbide or zirconium carbide, or a combination of at least two thereof; Preferably, the expansion coefficient regulator includes any one of NaAlSi3O8, CaMoO4, B2O3, SiO2 or ZrW2O8, or a combination of at least two thereof.

4. The graphene heating module according to any one of claims 1 to 3, characterized in that: A first conductive electrode and a second conductive electrode are also provided on the surface of the graphene heating film away from the carrier plate, and the first conductive electrode and the second conductive electrode are respectively located at two opposite edges on the surface of the graphene heating film; Preferably, the encapsulation protection layer covers the exposed outer surface of the graphene heating film outside the area where the first conductive electrode and the second conductive electrode are located, and the encapsulation protection layer is directly in contact with and connected to both the first conductive electrode and the second conductive electrode; Preferably, the thickness of the carrier plate is 2-4 mm; Preferably, the material of the carrier plate includes any one of quartz glass, borosilicate glass, aluminosilicate glass or high-aluminum glass, or a combination of at least two thereof; Preferably, the thickness of the graphene heating film is 200-450 μm; Preferably, the thickness of the packaging protection layer located on the surface of the graphene heating film away from the carrier board is 400-900 μm; Preferably, the material of the first conductive electrode and the second conductive electrode is independently selected from any one or a combination of at least two of copper, aluminum, silver, gold or copper plated with silver, preferably silver or copper; Preferably, the thickness of the first conductive electrode and the second conductive electrode are independently selected from 300 μm or less; Preferably, the working temperature of the graphene heating module is 0-800°C; Preferably, the graphene heating film has a temperature tolerance of 0-1800°C.

5. A method for preparing a graphene heating module according to any one of claims 1 to 4, characterized in that: The preparation method comprises the following steps: A graphene heating film made of dopant-modified graphene is arranged on a carrier plate, and a packaging protective layer is prepared on the exposed outer surface of the graphene heating film to obtain the graphene heating module; The material of the packaging protection layer includes a matrix inorganic substance and an expansion coefficient regulator; below 800° C., the relative difference percentage of the thermal expansion coefficients of the carrier board and the packaging protection layer is ≤10%.

6. The preparation method according to claim 5, characterized in that: The dopant comprises any one of metal, non-metal, organic small molecule, conductive polymer or low-dimensional material or a combination of at least two thereof; Preferably, the method of modifying the graphene with the dopant includes any one of vapor deposition method, hydrothermal method, solid phase synthesis method or electrochemical method or a combination of at least two thereof, for preparing the graphene heating film; Preferably, the specific preparation process of the encapsulation protective layer includes: mixing the matrix inorganic substance and the expansion coefficient regulating agent according to the formula amount, then adding a solvent and a film-forming agent to mix evenly to obtain an encapsulation protective layer precursor slurry, coating the encapsulation protective layer precursor slurry on the exposed outer surface of the graphene heating film, and then curing to obtain the encapsulation protective layer; Preferably, during the preparation of the encapsulation protection layer, the curing temperature is 100-400° C.; Preferably, in the process of preparing the encapsulation protection layer precursor slurry, the mass ratio of the total mass of the matrix inorganic substance and the expansion coefficient regulator to the mass ratio of the solvent is (1-5):1; Preferably, in the process of preparing the encapsulation protection layer precursor slurry, the mass ratio of the total mass of the matrix inorganic substance and the expansion coefficient regulating agent to the mass ratio of the film-forming agent is (0.5-2):

1.

7. The preparation method according to claim 5 or 6, characterized in that: Before preparing the encapsulation protection layer on the surface of the graphene heating film, a first conductive electrode and a second conductive electrode are arranged on the surface of the graphene heating film away from the carrier, and the first conductive electrode and the second conductive electrode are respectively arranged at the edges of the two opposite ends of the surface of the graphene heating film; Preferably, the first conductive electrode and the second conductive electrode are each independently arranged in a manner selected from any one of welding, printing or crimping.

8. A curing system for a graphene heating module, characterized in that: The curing system comprises the graphene heating module according to any one of claims 1 to 4, a temperature control module connected to the graphene heating module, and a control module connected to the temperature control module.

9. The curing system according to claim 8, characterized in that The temperature control module includes a monitoring element, a temperature controller and a data acquisition element; Preferably, the operating temperature of the temperature control module is 0-800°C; Preferably, the monitoring element includes a temperature sensor and an infrared probe; Preferably, one end of the temperature sensor is arranged close to the surface of the carrier plate in the graphene heating module away from the graphene heating film, so as to monitor the temperature of the graphene heating module; the other end of the temperature sensor is electrically connected to the data acquisition element, so as to collect the temperature of the graphene heating module in real time; Preferably, the infrared probe is a non-contact infrared probe, which is arranged close to the graphene heating module and connected to the data acquisition element, and is used to monitor the infrared radiation wavelength of the graphene heating module in real time; Preferably, the temperature controller is connected to the first conductive electrode and the second conductive electrode in the graphene heating module through a first circuit wire and a second circuit wire respectively; Preferably, the temperature controller and the data acquisition element are both connected to the control module.

10. The curing system according to claim 9, characterized in that The control module includes a programmable logic controller and a user interface; Preferably, the programmable logic controller is connected to both the data acquisition element and the temperature controller, and is used to analyze and process the processing data collected by the data acquisition element, and to set the output parameters of the temperature controller; Preferably, the curing system further comprises a power supply; Preferably, the power supply is connected to the graphene heating module through the temperature controller.

Images