Aerogel composites, heat resistant pads including the same, and methods for manufacturing heat resistant pads

Abstract

The method for manufacturing a heat-resistant mat according to the present application includes the steps of mixing a fluorine-based resin and aerogel particles in a solid phase at a weight ratio of 1:1 to 1:1.5 to form an aerogel composite material; and forming an aerogel composite material sheet to form an insulating layer.

Description

Technical Field

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2024-0086361, filed on July 1, 2024, and Korean Patent Application No. 10-2025-0085474, filed on June 26, 2025, the disclosures of which are incorporated herein by reference in their entirety.

[0003] This disclosure relates to an aerogel composite material, a heat-resistant pad including the aerogel, and a method for producing the heat-resistant pad, and more specifically, to a method for producing the heat-resistant pad, the method comprising a method for producing the heat-resistant pad including the aerogel by a dry process. Background Technology

[0004] With technological advancements and increasing demand for mobile devices, the need for secondary batteries as an energy source has grown rapidly. In particular, secondary batteries have attracted considerable attention as an energy source for power-driven devices such as electric bicycles, electric vehicles, and hybrid electric vehicles, as well as for mobile devices such as mobile phones, digital cameras, laptops, and wearable devices.

[0005] Secondary battery cells are manufactured by incorporating electrode assemblies and electrolytes together into a secondary battery casing, and the electrode assemblies are manufactured by stacking and / or winding positive electrodes, separators, and negative electrodes. The manufactured battery cells are stacked in multiple quantities to form battery modules or battery packs.

[0006] The driving force of the battery cell may generate heat in the battery cell, and if the heat is transferred to adjacent battery cells and accumulates, battery heat propagation may occur.

[0007] To prevent these problems, numerous studies have been conducted to prevent internal combustion of battery packs by placing heat-resistant pads between battery cells. In particular, heat-resistant pads with excellent heat resistance and high production efficiency have been studied. Summary of the Invention

[0008] Technical issues

[0009] This disclosure has been designed to address the aforementioned problems, and one object of it is to provide a method for producing an insulation layer comprising an aerogel composite material and a heat-resistant pad comprising the insulation layer by a dry process.

[0010] Another object of this disclosure is to provide an aerogel composite material and a heat-resistant pad, the heat-resistant pad including an insulation layer comprising an aerogel composite material.

[0011] Technical solution

[0012] According to an aspect of this disclosure, a method for producing a heat-resistant pad is provided, the method comprising the steps of: mixing a fluoropolymer resin and aerogel particles in a weight ratio of more than 1:1 and less than 1:1.5 in a solid state to form an aerogel composite material; and forming the aerogel composite material into a sheet to form an insulating layer.

[0013] In one embodiment, the formation of the aerogel composite material is performed in one step.

[0014] In one embodiment, the step of forming the aerogel composite material may include the following steps: a first step of mixing ceramic particles and the fluoropolymer in a solid state to form a precursor; and a second step of mixing the precursor and the aerogel particles in a solid state to form the aerogel composite material.

[0015] In one embodiment, in the first step, the mixing weight ratio of the ceramic particles to the fluoropolymer resin can be greater than 2:1 and less than 9:1.

[0016] In one embodiment, the first step may be a step of mixing the ceramic particles and the fluoropolymer resin while applying shear stress.

[0017] In one embodiment, the second step may be a step of kneading and mixing the precursor and the aerogel particles.

[0018] In one embodiment, the ceramic particles may include one or more selected from the group consisting of silicon dioxide, zirconium-based oxides, yttrium-based oxides, aluminum oxide (Al2O3), boehmite, aluminum trihydrate, calcium oxide, phosphate-based oxides, phosphorus pentoxide (P2O5), glass fibers, glass microspheres, and chopped glass.

[0019] In one embodiment, the fluoropolymer resin may include one or more selected from the group consisting of polytetrafluoroethylene (PTFE) resin, polyfluoroalkoxy (PFA) resin, and polyvinylidene fluoride (PVDF) resin.

[0020] In one embodiment, the aerogel particles may include silica aerogel particles.

[0021] In one embodiment, forming the aerogel composite material into a sheet can be achieved by pressing the aerogel composite material.

[0022] In one embodiment, the thermal conductivity of the insulation layer can be above 0.02 W / m·K and below 0.1 W / m·K.

[0023] In one embodiment, the method further includes the step of forming a support layer on at least one surface of the insulation layer, wherein the support layer may include one or more selected from the group consisting of silicone resin, aramid fiber, yarn, mica pad and mica paper.

[0024] In one embodiment, the silicone-based resin may be silicone rubber.

[0025] According to another aspect of this disclosure, an aerogel composite material is provided, the aerogel composite material comprising a fluoropolymer resin and aerogel particles in a weight ratio of 1:1 or more and 1:1.5 or less.

[0026] In one embodiment, the aerogel particles may include silica aerogel particles.

[0027] In one embodiment, the fluoropolymer resin may include one or more selected from the group consisting of polytetrafluoroethylene (PTFE) resin, polyfluoroalkoxy (PFA) resin, and polyvinylidene fluoride (PVDF) resin.

[0028] In one embodiment, the aerogel composite material may further include ceramic particles.

[0029] In one embodiment, the mixing weight ratio of the ceramic particles to the fluoropolymer resin can be greater than 2:1 and less than 9:1.

[0030] In one embodiment, the ceramic particles may include one or more selected from the group consisting of silicon dioxide, zirconium-based oxides, yttrium-based oxides, aluminum oxide (Al2O3), boehmite, aluminum trihydrate, calcium oxide, phosphate-based oxides, phosphorus pentoxide (P2O5), glass fibers, glass microspheres, and chopped glass.

[0031] According to another aspect of this disclosure, a heat-resistant pad is provided, the heat-resistant pad including an insulation layer comprising the aforementioned aerogel composite material.

[0032] Beneficial effects

[0033] This disclosure provides a method for producing an insulation layer comprising an aerogel composite material using a dry process, thereby producing a heat-resistant pad with high cost competitiveness and high process efficiency.

[0034] Furthermore, this disclosure may provide an aerogel composite material produced by the above method and a heat-resistant pad including the same. Attached Figure Description

[0035] Figure 1 This is a photograph of the aerogel composite material produced in Example 1.

[0036] Figure 2 This is a SEM image of the aerogel composite material produced in Example 1.

[0037] Figure 3 This is a SEM image of the aerogel composite material produced in Example 1.

[0038] Figure 4 This is a photograph of the aerogel composite material produced in Example 2.

[0039] Figure 5 This is a SEM image of the aerogel composite material produced in Example 2.

[0040] Figure 6 This is a SEM image of the aerogel composite material produced in Example 2.

[0041] Figure 7 This is a SEM image of the aerogel composite material produced in Example 3.

[0042] Figure 8 This is a SEM image of the aerogel composite material produced in Example 3.

[0043] Figure 9 This is an image of the insulation layer produced in Example 3.

[0044] Figure 10 This is an image of the heat-resistant pad produced in Example 3.

[0045] Figure 11 This is a SEM image of the mixture of fluoropolymer resin and aerogel particles produced in Comparative Example 1.

[0046] Figure 12 This is an image of a mixture of ceramic particles, fluoropolymer resin, and aerogel particles produced in Comparative Example 2.

[0047] Figure 13 This is an image of a mixture of ceramic particles, fluoropolymer resin, and aerogel particles produced in Comparative Example 3.

[0048] Figure 14 yes Figure 13 SEM image of the mixture.

[0049] Figure 15 This is an image of a mixture of ceramic particles, fluoropolymer resin, and aerogel particles produced in Comparative Example 4.

[0050] Figure 16 yes Figure 15 SEM image of the mixture.

[0051] Figure 17 This is an image of the mixture of fluoropolymer resin and aerogel particles produced in Comparative Example 5. Detailed Implementation

[0052] Various embodiments of this disclosure will be described in detail below with reference to the accompanying drawings, enabling those skilled in the art to readily implement them. This disclosure can be modified in various different ways and is not limited to the embodiments set forth herein.

[0053] For clarity in describing this disclosure, descriptions of parts unrelated to this disclosure will be omitted, and identical or similar components will be indicated by the same reference numerals throughout the description.

[0054] Because the dimensions and thicknesses of each component are shown arbitrarily for ease of description, this disclosure is not necessarily limited to the dimensions and thicknesses shown. The thicknesses are depicted at an enlarged scale to clearly show the different layers and regions. Furthermore, the thickness of a particular layer or region is exaggerated in the figures for ease of description.

[0055] When layers, films, regions, plates, etc., are arranged "on" a specific component, the description includes not only cases where the layers, films, regions, plates, etc., are arranged "directly" on the specific component, but also cases where the layers, films, regions, plates, etc., are arranged on the specific component via another component. When a component is arranged "directly" on another component, this indicates that there is no new component between the two components. Furthermore, when a component is arranged "on" a reference component, this indicates that the component exists on top of or below the reference component, and does not necessarily indicate that the component is arranged only on the top of the reference component away from the direction of gravity.

[0056] Throughout this document, when a component “includes” an element, it does not mean that the component excludes other components, but rather that the component may include other components, unless otherwise defined.

[0057] Now, an aerogel composite material according to the present disclosure, a heat-resistant pad including the same, and a method for producing the heat-resistant pad will be described.

[0058] The method for producing heat-resistant pads according to this disclosure includes the following steps: Fluoropolymer resin and aerogel particles are mixed in a solid state at a weight ratio of 1:1 or greater and 1:1.5 or less to form an aerogel composite material; and Aerogel composites are formed into sheets to create an insulation layer.

[0059] The method for producing a heat-resistant pad according to this disclosure relates to a method for producing a heat-resistant pad including an insulation layer, and the heat-resistant pad produced by the method of this disclosure may include only the insulation layer, or may further include a support layer disposed on at least one surface of the insulation layer. Embodiments of this method for producing a heat-resistant pad will now be described in detail.

[0060] According to one embodiment, a method for producing a heat-resistant pad includes the following steps: mixing fluoropolymer resin and aerogel particles in a weight ratio of 1:1 or more and 1:1.5 or less in a solid state to form an aerogel composite material; and forming the aerogel composite material into a sheet to form an insulating layer.

[0061] In one embodiment, the step of forming the aerogel composite material can be performed in a single step. That is, the step of forming the aerogel composite material can be a step of mixing powdered fluoropolymer resin and powdered aerogel particles in a solid state.

[0062] Mixing can be done using a device that can apply shear stress, such as a household mixer.

[0063] In one embodiment, the fluoropolymer resin may include one or more selected from the group consisting of polytetrafluoroethylene (PTFE) resin, polyfluoroalkoxy (PFA) resin, and polyvinylidene fluoride (PVDF) resin. For example, polytetrafluoroethylene (PTFE) resin can be used as a fluoropolymer resin, but the embodiments are not limited thereto.

[0064] In one embodiment, the aerogel particles can be inorganic aerogel particles, particularly silica aerogel particles. Aerogel particles have excellent thermal insulation properties and are therefore used as a major component in the production of thermal insulation layers.

[0065] The fluoropolymer resin and aerogel particles are supplied in powder form and mixed in a solid state. That is, the fluoropolymer resin and aerogel particles are mixed in a dry state without a separate solvent.

[0066] Typically, wet production processes for aerogel composites require approximately 1 to 3 days to grow the aerogel precursor on the surface of a support such as glass fiber, followed by a process that selectively removes the solvent from the aerogel precursor using methods such as supercritical fluid dynamics or room temperature pressurization, resulting in high process costs. In contrast, the advantages of this disclosure are that, because the aerogel composite is formed by dry mixing of fluoropolymer resin and aerogel particles, the process time is within 10 minutes. This process is simpler than wet production processes and is relatively faster and less costly.

[0067] Fluoropolymer resins and aerogel particles can be mixed at a weight ratio of fluoropolymer resin to aerogel particles of 1:1 or higher but less than 1:1.5. When the amount of aerogel particles decreases and the weight ratio of fluoropolymer resin to aerogel particles (fluoropolymer weight: aerogel particle weight) is less than 1:1, it may be difficult to form a pad of the aerogel composite material, or even if the aerogel composite material and insulation layer can be produced, the produced insulation layer may not exhibit sufficient insulation performance. When the amount of aerogel particles increases and the weight ratio of fluoropolymer resin to aerogel particles (fluoropolymer weight: aerogel particle weight) exceeds 1:1.5, the amount of fluoropolymer resin used as a mesh to connect the aerogel particles decreases relatively, making it difficult to form a pad of the aerogel composite material. In other words, it is difficult to produce an insulation layer.

[0068] In this disclosure, fluoropolymer resin and aerogel particles are mixed in a solid state at a weight ratio of 1:1 or higher and 1:1.5 or lower to form an aerogel composite material, thereby providing a dry production method for aerogel composite materials and providing an aerogel composite material that is highly price-competitive, has excellent thermal insulation properties, and is easy to form into a pad.

[0069] The aerogel composite material formed as described above can be formed into sheets and produced as an insulation layer. Forming the aerogel composite material into sheets involves pressing the aerogel composite material and forming it into a sheet. Pressing can be performed by known methods, such as calendering.

[0070] In one embodiment, when the step of forming the aerogel composite material is performed in one step, it may include the step of mixing fluoropolymer and aerogel particles in a weight ratio of more than 1:1 and less than 1:1.5 in the solid state to form the aerogel composite material, and the step of forming the aerogel composite material into a sheet to form an insulating layer.

[0071] In another embodiment, the step of forming the aerogel composite material can be performed in two or more steps, for example, in two steps.

[0072] In one embodiment, the step of forming an aerogel composite material may include a first step of mixing ceramic particles and fluoropolymer in a solid state to form a precursor, and a second step of mixing the precursor and aerogel particles in a solid state to form an aerogel composite material.

[0073] The first step is to mix powdered ceramic particles and powdered fluoropolymer resin in a solid state to form a precursor.

[0074] The first step is the process for fiberizing the fluoropolymer resin. Fiberization of the fluoropolymer resin can be more easily induced by mixing ceramic particles into it. This first step can be performed using a device capable of applying shear stress, such as a household mixer. The mixing of the ceramic particles and the fluoropolymer resin is carried out without a separate solvent, i.e., by a dry process. Therefore, the process is less time-consuming and relatively inexpensive.

[0075] In this embodiment, ceramic particles and fluoropolymer resin can be mixed in a weight ratio of ceramic particles to fluoropolymer resin of 2:1 or more and 9:1 or less. When the above ratio is met, the fluoropolymer resin can be easily fibroinated.

[0076] In one embodiment, the ceramic particles may include one or more selected from the group consisting of silicon dioxide, zirconium-based oxides, yttrium-based oxides, alumina (Al2O3), boehmite, aluminum trihydrate, calcium oxide, phosphate-based oxides, phosphorus pentoxide (P2O5), glass fiber, glass bubbles, and chopped glass. For example, milled glass fiber, chopped glass, silicon dioxide, zirconium oxide, or alumina processed into ceramic particles may be used, and more specifically, milled glass fiber and chopped glass may be mixed and used, but the embodiments are not limited thereto.

[0077] The description of fluoropolymers applies in the same manner as described above.

[0078] The second step involves mixing the precursor formed in the first step with the aerogel particles in a solid state to form an aerogel composite material. The aerogel particles are described in the same manner as described above.

[0079] The mixing of the precursor and aerogel particles is performed via a dry process without the use of a separate solvent. Therefore, the process is less time-consuming and relatively inexpensive.

[0080] When the precursor and aerogel particles are mixed, they can be mixed based on the weight ratio of the fluoropolymer contained in the precursor to the aerogel particles. That is, the precursor and aerogel particles are mixed such that the weight ratio of the fluoropolymer contained in the precursor to the aerogel particles is greater than 1:1 and less than 1:1.5. When the above ratio is met, the fluoropolymer can be easily fibroinated.

[0081] The second step can be performed by kneading the precursor and aerogel particles produced in the first step. For example, the process of kneading the precursor and aerogel particles can be carried out using a PD mixer (planetary disperser mixer) or a twin screw extruder.

[0082] In this embodiment, if the first and second steps are performed in one step, i.e., if the ceramic particles, fluoropolymer, and aerogel particles are mixed simultaneously in a solid state, a problem of aerogel particle breakage may occur. Due to this particle breakage, the specific surface area of ​​the aerogel particles increases, and the proportion of fluoropolymer that can cover the surface of the aerogel particles becomes relatively low, and the formation of the aerogel composite pad may not be possible.

[0083] Therefore, when ceramic particles are added, the aerogel composite material is formed by dividing the process into a first step and a second step as described above. The insulating layer can then be formed by shaping the aerogel composite material into a sheet. The sheet formation of the aerogel composite material can be performed using the pressing method described above.

[0084] In the method for producing a heat-resistant pad according to the present disclosure, a fluoropolymer resin, aerogel particles and optional ceramic particles are mixed in a solid state to form an aerogel composite material, and the aerogel composite material can be formed into a sheet to produce an insulation layer.

[0085] The thermal conductivity of the insulation layer can be above 0.02 W / m·K and below 0.1 W / m·K. The insulation layer of this disclosure comprises aerogel particles, thus exhibiting excellent heat resistance, and is produced by a dry process, which reduces process time and cost compared to a wet process.

[0086] On the other hand, a method for producing a heat-resistant pad according to one embodiment can provide a method for producing an insulation layer. That is, a heat-resistant pad produced according to a method for producing a heat-resistant pad according to one embodiment can provide the aforementioned insulation layer.

[0087] A method for producing a heat-resistant pad according to another embodiment of the present disclosure may include the steps of forming an insulation layer and forming a support layer. That is, a heat-resistant pad produced according to one embodiment of the method for producing a heat-resistant pad may include an insulation layer and a support layer disposed on at least one surface of the insulation layer.

[0088] The steps for forming the insulation layer are the same as those described above for producing the insulation layer. That is, the steps for forming the insulation layer are performed by forming an aerogel composite material in one or both of the steps described above, and by forming the aerogel composite material into a sheet to form the insulation layer. Detailed descriptions of these steps will be omitted.

[0089] The step of forming the support layer is to form the support layer on at least one surface of the insulation layer. For example, the support layer may be formed on both surfaces of the insulation layer, but the implementation is not limited to this.

[0090] The support layer may include a heat-resistant material. Specifically, the support layer may include one or more materials selected from the group consisting of silicone-based resins, fabrics, and ceramic materials, and the silicone-based resin may be, for example, silicone rubber. The fabric may be, for example, aramid fiber or spun yarn. The ceramic material may be, for example, a mica pad or mica paper. That is, the support layer may include one or more materials selected from the group consisting of silicone-based resins, aramid fibers, spun yarn, mica pads, and mica paper.

[0091] In one embodiment, the support layer may be silicone rubber. In this case, the support layer can be formed by coating and curing a silicone rubber solution on at least one surface of the insulation layer. However, the implementation of the support layer is not limited to this.

[0092] In one embodiment, the support layer is made of silicone rubber as an adhesive layer, and may also include one or more materials selected from the group consisting of fabrics or ceramic materials. In this case, a silicone rubber solution may be applied to at least one surface of the insulation layer, fabrics or ceramic materials may be adhered to the silicone rubber solution, and then the silicone rubber solution may be cured to form the support layer.

[0093] According to one embodiment, a method for producing a heat-resistant pad can provide a method for providing a heat-resistant pad comprising an insulating layer and a support layer. The heat-resistant pad thus provided can further improve its strength and flexibility. This heat-resistant pad can be disposed, for example, between battery cells, to prevent heat generated from one battery cell from being transferred to adjacent battery cells and accumulating in adjacent battery cells, thereby preventing thermal runaway.

[0094] The aerogel composite materials disclosed herein include: Fluoropolymer resins and aerogel particles with a weight ratio of 1:1 or higher and 1:1.5 or lower.

[0095] In one embodiment, the aerogel composite material can be produced according to the step of forming the aerogel composite material in the method for producing heat-resistant pads described above. That is, the aerogel composite material of one embodiment can be formed by mixing fluoropolymer resin and aerogel particles in a weight ratio of 1:1 or more and 1:1.5 or less in the solid state. Therefore, the details of the fluoropolymer resin and aerogel particles in the aerogel composite material of this disclosure are applied in the same manner as described above.

[0096] In one embodiment, the aerogel particles may include silica aerogel particles.

[0097] In a further embodiment, the fluoropolymer resin may include one or more selected from the group consisting of polytetrafluoroethylene (PTFE) resin, polyfluoroalkoxy (PFA) resin, and polyvinylidene fluoride (PVDF) resin.

[0098] In one embodiment, the aerogel composite material may further include ceramic particles to facilitate the fibrosis of the fluoropolymer. That is, the aerogel composite material of one embodiment can be formed by a first step of mixing ceramic particles and fluoropolymer in a solid state to form a precursor, and a second step of mixing the precursor and aerogel particles in a solid state to form the aerogel composite material. Therefore, the details of the ceramic particles in the aerogel composite material of this disclosure apply in the same manner as described above.

[0099] In one embodiment, the mixing weight ratio of ceramic particles and fluorinated resin can be 2:1 or higher and 9:1 or lower. Furthermore, in one embodiment, the ceramic particles may include one or more selected from the group consisting of silicon dioxide, zirconium oxide, yttrium oxide, alumina (Al2O3), boehmite, aluminum trihydrate, calcium oxide, phosphate oxide, phosphorus pentoxide (P2O5), glass fiber, glass microspheres, and chopped glass.

[0100] The aerogel composite material disclosed herein comprises a fluoropolymer resin and aerogel particles in a weight ratio of 1:1 or more and 1:1.5 or less, thus exhibiting excellent thermal insulation properties, being easily formed into sheets, and having excellent processability.

[0101] The heat-resistant pad disclosed herein includes: The insulation layer comprises the aerogel composite material.

[0102] In one embodiment, the heat-resistant pad includes an insulation layer comprising the aforementioned aerogel composite material. Specifically, the insulation layer can be formed by forming the aforementioned aerogel composite material into a sheet. The sheet-forming method can be similarly applied to the step described in the method for producing the heat-resistant pad above, where the insulation layer is formed by forming the aerogel composite material into a sheet.

[0103] In a further embodiment, the heat-resistant pad of this disclosure may include an insulation layer and a support layer disposed on at least one surface of the insulation layer. Details of the support layer may be applied in the same manner as described above.

[0104] The heat-resistant pad disclosed herein includes an insulating layer comprising an aerogel composite material, thus exhibiting excellent heat resistance. Furthermore, in addition to the insulating layer, the heat-resistant pad of the present invention also includes a support layer, thereby improving flexibility.

[0105] Embodiments of this disclosure will be described in detail below to enable those skilled in the art to readily implement this disclosure. However, this disclosure can be modified in various different forms and is not limited to the embodiments described herein.

[0106] <Example 1>

[0107] Fluoropolymer resin and aerogel particles were mixed in a 1:1 weight ratio in the solid state to form an aerogel composite material. PTFE was used as the fluoropolymer resin, and silica aerogel particles were used as the aerogel particles. Mixing was performed for 15 minutes at 3500 rpm using a household mixer.

[0108] Figure 1 This is a photograph of the aerogel composite material produced in Example 1. Figure 2 and Figure 3 This is a SEM image of the aerogel composite material produced in Example 1. (Refer to...) Figures 1 to 3 It can be confirmed that the fluoropolymer is adsorbed on the surface of the aerogel particles, and the aerogel particles are uniformly bonded to each other by the fluoropolymer.

[0109] <Example 2>

[0110] Fluoropolymer resin and aerogel particles were mixed in a solid state at a weight ratio of 1:1.5 to form an aerogel composite material. PTFE was used as the fluoropolymer resin, and silica aerogel particles were used as the aerogel particles. The mixture was stirred for 15 minutes at 3500 rpm using a household stirrer.

[0111] Figure 4 This is a photograph of the aerogel composite material produced in Example 2. Figure 5 and Figure 6 This is a SEM image of the aerogel composite material produced in Example 2.

[0112] Reference Figures 4 to 6 It can be confirmed that the fluoropolymer is adsorbed on the surface of the aerogel particles, thus the aerogel particles are uniformly connected and bonded to each other.

[0113] <Example 3>

[0114] Ceramic particles and fluoropolymer resin were mixed in a 2:1 weight ratio in the solid state to form a precursor. Alumina (Al₂O₃) was used as the ceramic particles, and PTFE was used as the fluoropolymer resin. The mixture was stirred for 15 minutes at 3500 rpm using a household mixer.

[0115] The resulting precursor was mixed with aerogel particles in a solid state to form an aerogel composite material. At this stage, the aerogel particles and the fluoropolymer contained in the precursor were mixed at a 1:1 weight ratio. Silica aerogel particles were used as the aerogel particles. Mixing was performed using a HIVIS Mix (planetary mixer) purchased from PRIMIX at 45 rpm for 45 minutes.

[0116] Figure 7 and Figure 8 This is a SEM image of the aerogel composite material produced in Example 3. (Refer to...) Figure 7 and Figure 8 It can be confirmed that the precursor, which is a mixture of ceramic particles and fluoropolymer resin, exists in a network shape and covers the aerogel.

[0117] Subsequently, the resulting aerogel composite material was pressed using an automatic air hot press (air heating plate tester, model QM940AS) purchased from QMESYS and formed into sheets to form an insulation layer. Figure 9 This is an image of the insulation layer produced in Example 3. (See reference...) Figure 9 This confirms that the insulation layer has a sheet shape.

[0118] Subsequently, a silicone rubber solution is sprayed onto both surfaces of the formed insulation layer and thermosetting to form a support layer. The silicone rubber solution is a mixture of PDMS (polydimethylsiloxane), a crosslinking agent, and a platinum (Pt) catalyst in a weight ratio of PDMS:crosslinking agent:platinum catalyst = 100:1:1. The thermosetting process is carried out in an oven at 80°C for 10 minutes. This produces a heat-resistant pad comprising an insulation layer and a support layer. Figure 10 This is an image of the heat-resistant pad produced in Example 3. (See reference) Figure 10 It can be confirmed that the heat-resistant pad bends in one direction, including the support layer. In other words, it can be confirmed that the heat-resistant pad includes a support layer, thereby further enhancing its flexibility.

[0119] <Comparative Example 1>

[0120] An experiment was conducted to mix fluoropolymer resin and aerogel particles in a 1:5 weight ratio in the solid state to form an aerogel composite material. PTFE was used as the fluoropolymer resin, and silica aerogel particles were used as the aerogel particles. The mixture was stirred for 15 minutes at 3500 rpm using a household mixer.

[0121] Figure 11This is a SEM image of the mixture of fluoropolymer resin and aerogel particles produced in Comparative Example 1. Figure 11 As shown, in Comparative Example 1, the fluoropolymer and aerogel were not mixed, and therefore no aerogel composite material was formed. This is presumably because the amount of fluoropolymer per unit volume was smaller compared to Examples 1 and 2, making it difficult to form a web through fibrosis.

[0122] Since no aerogel composite material is formed, it is impossible to produce an insulation layer, and therefore impossible to produce a heat-resistant pad.

[0123] <Comparative Example 2>

[0124] Ceramic particles, fluoropolymer resin, and aerogel particles were mixed in a solid state at a weight ratio of 2:1:4, and the mixing was carried out simultaneously in one step. Alumina (Al2O3) was used as the ceramic particles, PTFE as the fluoropolymer resin, and silica aerogel particles as the aerogel particles.

[0125] Mix for 15 minutes at 3500 rpm using a household blender.

[0126] Figure 12 This is an image of a mixture of ceramic particles, fluoropolymer resin, and aerogel particles produced in Comparative Example 2.

[0127] Reference Figure 12 The mixture did not form a pad, and due to dust, SEM analysis was not possible.

[0128] <Comparative Example 3>

[0129] Ceramic particles and fluoropolymer resin were mixed in a 1:1 weight ratio in the solid state to form a precursor. Alumina (Al₂O₃) was used as the ceramic particles, and PTFE was used as the fluoropolymer resin. The mixture was stirred for 15 minutes at 3500 rpm using a household mixer.

[0130] The resulting precursor was mixed with aerogel particles in a solid state to form an aerogel composite material. At this stage, the aerogel particles were mixed in an amount four times the weight of the fluoropolymer contained in the precursor. Silica aerogel particles were used as the aerogel particles. Mixing was performed for 45 minutes at 45 rpm using a HIVIS Mix (planetary mixer) purchased from PRIMIX.

[0131] Figure 13 This is an image of a mixture of ceramic particles, fluoropolymer resin, and aerogel particles produced in Comparative Example 3. Figure 14 yes Figure 13 SEM image of the mixture.

[0132] Reference Figure 13This confirms that the aerogel composite material did not form and the mixture existed in powder form. (Refer to...) Figure 14 It can be confirmed that, due to the relatively high ratio of aerogel particles to precursors, only some aerogel particles form complexes with the precursors, and there are more aerogel particles that do not form complexes with the precursors.

[0133] <Comparative Example 4>

[0134] Ceramic particles and fluoropolymer resin were mixed in a solid state at a weight ratio of 10:1 to form a precursor. Alumina (Al₂O₃) was used as the ceramic particles, and PTFE was used as the fluoropolymer resin. The mixture was stirred for 15 minutes at 3500 rpm using a household mixer.

[0135] The resulting precursor was mixed with aerogel particles in a solid state to form an aerogel composite material. At this stage, the aerogel particles were mixed in an amount four times the weight of the fluoropolymer contained in the precursor. Silica aerogel particles were used as the aerogel particles. Mixing was performed for 45 minutes at 45 rpm using a HIVIS Mix (planetary mixer) purchased from PRIMIX.

[0136] Figure 15 This is an image of a mixture of ceramic particles, fluoropolymer resin, and aerogel particles produced in Comparative Example 4. Figure 16 yes Figure 15 SEM image of the mixture.

[0137] Reference Figure 15 This confirms that the aerogel composite material did not form and the mixture existed in powder form. Furthermore, refer to... Figure 16 It can be confirmed that ceramic particles are densely distributed in the aerogel composite, and some ceramic particles aggregate together because the proportion of ceramic particles is very high. It can be confirmed that aerogel particles are partially present between the ceramic particles, and there is insufficient bonding between the precursor and the aerogel particles.

[0138] <Comparative Example 5>

[0139] Fluoropolymer resin and aerogel particles were mixed in a solid state at a weight ratio of 2:1 to form an aerogel composite material. PTFE was used as the fluoropolymer resin, and silica aerogel particles were used as the aerogel particles. The mixture was stirred for 15 minutes at 3500 rpm using a household stirrer.

[0140] Figure 17 This is an image of the mixture of fluoropolymer resin and aerogel particles produced in Comparative Example 5.

[0141] Reference Figure 17It can be confirmed that aggregates of fluoropolymer resin were found in the area indicated by the circle, and a large number of such aggregates were formed, indicating that the fluoropolymer resin and aerogel were not mixed. Since no aerogel composite material was formed, it was impossible to produce an insulation layer and a heat-resistant pad.

[0142] Referring together to Example 1, Example 2, Comparative Example 1, Comparative Example 2 and Comparative Example 5, it was confirmed that when the weight ratio of fluoropolymer resin and aerogel particles is adjusted to 1:1 or more and 1:1.5 or less during solid mixing, a uniform network is formed between the fluoropolymer resin and aerogel particles, and a pad can be formed.

[0143] Furthermore, referring together with Example 3, Comparative Example 3 and Comparative Example 4, it was confirmed that even if the ceramic particles, fluoropolymer resin and aerogel particles are mixed in two steps, it is difficult to form an aerogel composite material and a mat if the weight ratio of the ceramic particles, fluoropolymer resin and aerogel particles is outside the scope of this disclosure.

[0144] Referring to Examples 1 to 3, the method for producing a heat-resistant pad disclosed herein provides a method for mixing a fluoropolymer, aerogel particles and optional ceramic particles in a solid state, but mixing the fluoropolymer:aerogel particles in a weight ratio of more than 1:1 and less than 1:1.5 to form an aerogel composite material, and forming the formed aerogel composite material into a sheet to form an insulating layer.

[0145] The method for producing heat-resistant pads disclosed herein is performed using a dry process, which is excellent in terms of processability, and the heat-resistant pads produced thereby can have excellent thermal insulation properties. Furthermore, the heat-resistant pad of one embodiment of this disclosure can be provided with further improved strength and flexibility by further including the step of forming a support layer on the insulation layer.

[0146] Although preferred embodiments of the present disclosure have been shown and described above, the scope of the present disclosure is not limited thereto, and those skilled in the art can make many other changes and modifications to the embodiments using the basic principles of the invention as defined in the appended claims, which also fall within the spirit and scope of the invention.

Claims

1. A method for producing a heat-resistant pad, the method comprising the following steps: Fluoropolymer resin and aerogel particles are mixed in a solid state at a weight ratio of 1:1 or greater and 1:1.5 or less to form an aerogel composite material; and The aerogel composite material is formed into a sheet to form an insulation layer.

2. The method for producing heat-resistant pads according to claim 1, wherein, The formation of the aerogel composite material is performed in one step.

3. The method for producing heat-resistant pads according to claim 1, wherein, The step of forming the aerogel composite material includes the following steps: The first step involves mixing ceramic particles and the fluoropolymer resin in a solid state to form a precursor; and The second step involves mixing the precursor and the aerogel particles in a solid state to form the aerogel composite material.

4. The method for producing a heat-resistant pad according to claim 3, wherein, In the first step, the mixing weight ratio of the ceramic particles to the fluoropolymer resin is 2:1 or more and 9:1 or less.

5. The method for producing a heat-resistant pad according to claim 3, wherein, The first step is to mix the ceramic particles and the fluoropolymer resin while applying shear stress.

6. The method for producing a heat-resistant pad according to claim 3, wherein, The second step is to knead and mix the precursor and the aerogel particles.

7. The method for producing a heat-resistant pad according to claim 3, wherein, The ceramic particles include one or more selected from the group consisting of silicon dioxide, zirconium-based oxides, yttrium-based oxides, aluminum oxide (Al2O3), boehmite, aluminum trihydrate, calcium oxide, phosphate-based oxides, phosphorus pentoxide (P2O5), glass fibers, glass microspheres, and chopped glass.

8. The method for producing a heat-resistant pad according to claim 1, wherein, The fluoropolymer resin includes one or more selected from the group consisting of polytetrafluoroethylene (PTFE) resin, polyfluoroalkoxy (PFA) resin, and polyvinylidene fluoride (PVDF) resin.

9. The method for producing a heat-resistant pad according to claim 1, wherein, The aerogel particles include silica aerogel particles.

10. The method for producing a heat-resistant pad according to claim 1, wherein, Forming the aerogel composite material into a sheet involves pressing the aerogel composite material.

11. The method for producing a heat-resistant pad according to claim 1, wherein, The thermal conductivity of the insulation layer is above 0.02 W / m·K and below 0.1 W / m·K.

12. The method for producing a heat-resistant pad according to claim 1, the method further comprising the step of forming a support layer on at least one surface of the insulation layer. in, The support layer comprises one or more selected from the group consisting of silicone resin, aramid fiber, yarn, mica pad, and mica paper.

13. The method for producing a heat-resistant pad according to claim 12, wherein, The silicone-based resin is silicone rubber.

14. An aerogel composite material, the aerogel composite material comprising a fluoropolymer resin and aerogel particles in a weight ratio of 1:1 or more and 1:1.5 or less.

15. The aerogel composite material according to claim 14, wherein, The aerogel particles include silica aerogel particles.

16. The aerogel composite material according to claim 14, wherein, The fluoropolymer resin includes one or more selected from the group consisting of polytetrafluoroethylene (PTFE) resin, polyfluoroalkoxy (PFA) resin, and polyvinylidene fluoride (PVDF) resin.

17. The aerogel composite material according to claim 14, wherein, The aerogel composite material also includes ceramic particles.

18. The aerogel composite material according to claim 17, wherein, The mixing weight ratio of the ceramic particles to the fluoropolymer resin is greater than 2:1 and less than 9:

1.

19. The aerogel composite material according to claim 17, wherein, The ceramic particles include one or more selected from the group consisting of silicon dioxide, zirconium-based oxides, yttrium-based oxides, aluminum oxide (Al2O3), boehmite, aluminum trihydrate, calcium oxide, phosphate-based oxides, phosphorus pentoxide (P2O5), glass fibers, glass microspheres, and chopped glass.

20. A heat-resistant pad, the heat-resistant pad comprising an insulation layer, the insulation layer comprising the aerogel composite material according to claim 14.

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