Aerogel Blanket

Abstract

The present invention relates to an aerogel blanket comprising an aerogel having a low organic content and a method for making the same.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0051229, filed on April 19, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to an aerogel blanket comprising an aerogel having a low organic content and a method for making the same. [Background technology]

[0003] Electronic products such as laptops, OLEDs, and TVs have hot spots due to heat sources, which can partially dissipate heat on the device surface, reducing the perceived quality felt by consumers. Furthermore, if a simple insulation material is used and the heat is not properly dispersed to the outside, excessive heat buildup can cause system failure, shorten the product's lifespan, or in severe cases, cause an explosion or fire. To address these heat-related issues, various insulation materials have been applied, but an optimal insulation material that is thin and has excellent insulation performance has yet to be developed, and various research and technological development efforts are currently underway.

[0004] To solve these conventional problems, some applications involve aerogel, which has attracted attention as a highly efficient thermal insulation material. Aerogel is a highly porous material composed of nanoparticles, and has a high porosity, specific surface area, and low thermal conductivity. It is a material that has attracted attention as a highly efficient thermal insulation material, soundproofing material, and other applications.

[0005] However, despite its excellent material properties, aerogel is used only in very limited applications due to its complex manufacturing process and high manufacturing cost. Furthermore, its high porosity means that its mechanical strength is very weak, making it susceptible to even small impacts. Therefore, in recent years, research has been conducted into aerogel blanket composite technology that can overcome these drawbacks of aerogel itself and enable it to be processed into various shapes.

[0006] An aerogel blanket is a mattress or sheet made from aerogel material. Its flexibility allows it to be bent, folded, and cut. Its applications include pipe insulation, clothing, and a variety of other industrial applications. Its flexibility is possible because the aerogel blanket is a composite made of fiber and aerogel. The fiber enhances the aerogel blanket's flexibility and mechanical strength, while the aerogel provides insulation properties through its porosity. The core composite technology of aerogel blankets is the combination of the characteristics of fiber and aerogel, leveraging each other's advantages and complementing their shortcomings.

[0007] Such aerogel blankets are new materials that have superior heat resistance and insulation properties compared to conventional polymer insulation materials such as polystyrene foam and polyurethane foam, and are attracting attention as advanced materials that can solve energy conservation and environmental problems that will emerge in the future.

[0008] However, because such aerogels have very low mechanical strength due to their porous structure, they have been used to manufacture aerogel composites in which aerogel is impregnated and bonded to conventional insulating fibers, such as inorganic or organic fibers. However, the adhesion between the fibers and the aerogel in such aerogel composites is weak, and aerogel particles separate during processing such as cutting and bending, resulting in dust generation and reduced durability. This can cause damage to the equipment when used as an insulating material for electronic products, etc.

[0009] Thus, the reduction in battery capacity and the increase in size of battery modules and battery packs are not problems, and there is a strong need to develop materials that can prevent flames caused by ignition and explosion of battery modules and battery packs from spreading to adjacent battery modules. Summary of the Invention [Problem to be solved by the invention]

[0010] An object of the present invention is to provide an aerogel blanket that can effectively achieve heat insulation and fire prevention performance when used in articles such as batteries, and a heat insulating member including the aerogel blanket. [Means for solving the problem]

[0011] In order to solve the above problems, the present invention provides an aerogel blanket, an insulating member including the aerogel blanket, a battery including the insulating member, and a method for producing the aerogel blanket.

[0012] (1) The present invention provides an aerogel blanket comprising an aerogel and a blanket substrate, the aerogel blanket having an organic matter content of 1.2 wt % or less according to the following formula 1:

[0013] [Formula 1] Organic matter content (wt%)=[(Wa-Wb) / Wa]×100 In the formula 1, Wa is the weight (g) of the aerogel blanket before heat treatment, Wb is the weight (g) of the aerogel blanket after heat treatment at 600°C for 12 hours.

[0014] (2) In the present invention, there is provided the aerogel blanket according to (1) above, wherein the organic substance is at least one selected from the group consisting of a hydrophobic group bonded to the aerogel, a binder, and a sizing agent.

[0015] (3) The present invention provides the aerogel blanket according to (1) or (2) above, wherein the aerogel blanket has a room temperature thermal conductivity of 15 to 35 mW / mK.

[0016] (4) The present invention provides the aerogel blanket according to any one of (1) to (3) above, wherein the aerogel contains pores having a diameter of 10 to 50 nm.

[0017] (5) The present invention provides the aerogel blanket according to any one of (1) to (4), wherein the blanket substrate is one or more selected from the group consisting of a film, a sheet, a net, a fiber, a porous body, a foam, and a nonwoven fabric body.

[0018] (6) In the present invention, there is provided the aerogel blanket according to (5) above, wherein the blanket substrate is one or more selected from the group consisting of glass fiber, ceramic wool, basalt fiber, and ceramic paper.

[0019] (7) The present invention provides the aerogel blanket according to any one of (1) to (6) above, wherein the aerogel blanket has a water absorption rate of 100% by weight or more, as determined by the following formula 2:

[0020] [Formula 2] Water absorption rate (wt%) = [(Wc - Wd) / Wd] x 100 In the formula 2, Wc is the weight (g) of the aerogel blanket after immersion in distilled water at 21±2°C for 15 minutes, Wd is the weight (g) of the aerogel blanket before immersion in distilled water.

[0021] (8) The present invention provides the aerogel blanket according to any one of (1) to (7) above, wherein the aerogel blanket has a heat of combustion of 200 cal / g or less according to the ISO 1716 measurement method.

[0022] (9) In the present invention, there is provided the aerogel blanket according to any one of (1) to (8), which is manufactured by a manufacturing method including the steps of: 1) preparing a sol containing a precursor material and a catalyst composition; 2) impregnating a blanket substrate with the sol to gel it, thereby manufacturing a wet gel blanket; 3) modifying the surface of the wet gel blanket; 4) drying the surface-modified wet gel blanket; and 5) heat-treating the wet gel blanket at a temperature of 450 to 650°C for 10 minutes to 6 hours.

[0023] (10) The present invention provides the aerogel blanket according to any one of (1) to (9), wherein the aerogel blanket is produced by a production method including: 1) a step of preparing a sol containing a precursor material and a catalyst composition; 2) a step of impregnating a blanket substrate with the sol to gel it, thereby producing a wet gel blanket; and 3) a step of drying the wet gel blanket, wherein the blanket substrate is pretreated at a temperature of 400 to 500°C for 30 minutes to 2 hours, and the production method does not include a step of surface-modifying the wet gel blanket.

[0024] (11) The present invention provides a heat insulating member, including the aerogel blanket according to any one of (1) to (10) above.

[0025] (12) The present invention provides a battery including the heat insulating member according to (11) above.

[0026] (13) The present invention provides an aerogel blanket comprising an aerogel and a blanket substrate, the aerogel blanket having a compressibility of 15 to 30% according to the following formula 3:

[0027] [Formula 3] Compression ratio (%) = [(Ta - Tb) / Ta] x 100 In the formula 3, Ta is the thickness of the aerogel blanket before compression (mm), Tb is the thickness (mm) of the aerogel blanket after 350 kPa compression. [Effects of the Invention]

[0028] The aerogel blanket according to the present invention has a low organic content and exhibits excellent heat absorption and fire extinguishing properties, and when used in an article, it can effectively exert fire prevention and fire propagation functions. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a graph showing the pore distribution of the aerogel blankets of Example 1 and Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention will now be described in more detail so that the present invention may be more easily understood.

[0031] The terms and words used in the description of the present invention and the claims should not be interpreted in a limited way to their ordinary or dictionary meanings, but should be interpreted in a way that is consistent with the technical idea of ​​the present invention, based on the principle that the inventors can appropriately define the concepts of terms in order to best describe their invention.

[0032] The present invention will be described in detail below.

[0033] The aerogel blanket of the present invention comprises an aerogel and a blanket substrate, and is characterized in that the organic matter content according to the following formula 1 is 1.2 wt % or less.

[0034] [Formula 1] Organic matter content (wt%)=[(Wa-Wb) / Wa]×100 In the formula 1, Wa is the weight (g) of the aerogel blanket before heat treatment, Wb is the weight (g) of the aerogel blanket after heat treatment at 600°C for 12 hours.

[0035] Conventional aerogel blankets are manufactured through a hydrophobic process using a surface modification step, which inevitably requires the blanket to contain a certain amount of organic matter. When such aerogel blankets are exposed to high temperatures and high energy conditions, the hydrophobic surface groups introduced during the surface modification burn, generating flames, odors, and heat. This phenomenon limits the temperature range in which aerogel blankets can be used for applications such as insulation. In particular, aerogel blankets cannot be used in applications such as batteries that must be used at ultra-high temperatures of over 1000°C, or even if they are used, their performance is significantly reduced.

[0036] In contrast, the aerogel blanket of the present invention is characterized by a low organic content, as described above. This indicates that the aerogel blanket of the present invention contains a low content of hydrophobic groups, and therefore, phenomena such as heat generation caused by hydrophobic groups at high temperatures are suppressed. Unlike conventional aerogel blankets, the aerogel blanket of the present invention can be used as a heat insulating member even in extreme environments with very high temperatures.

[0037] In the present invention, the organic substance may be one or more selected from the group consisting of a hydrophobic group bonded to the aerogel, a binder, and a sizing agent. More specifically, the hydrophobic group may be an alkyl group such as a methyl group or an ethyl group, and the binder and sizing agent may be, but are not limited to, polystyrene, polybutyl acrylate, polyvinyl alcohol, polyester, polyurethane, epoxy resin, acrylic resin, or a combination thereof.

[0038] In the present invention, the aerogel blanket may have a room temperature thermal conductivity of 15 to 35 mW / mK, specifically 18 to 30 mW / mK, or 20 to 25 mW / mK.

[0039] The aerogel blanket of the present invention maintains a suitable thermal conductivity as described above and exhibits excellent high-temperature heat insulation performance.

[0040] In the present invention, the aerogel contained in the aerogel blanket may have pores with a diameter of 10 to 50 nm.

[0041] In the present invention, the aerogel blanket may have a water absorption rate of 100% by weight or more, specifically 150% by weight or more, as measured by ASTM C1511. Specifically, the water absorption rate can be calculated by the following Equation 2:

[0042] [Formula 2] Water absorption rate (wt%) = [(Wc - Wd) / Wd] x 100 In the formula 2, Wc is the weight (g) of the aerogel blanket after immersion in distilled water at 21±2°C for 15 minutes, Wd is the weight (g) of the aerogel blanket before immersion in distilled water.

[0043] The aerogel blanket of the present invention has a low organic content and a low degree of hydrophobicity, and can exhibit a high water absorption rate as described above.

[0044] In the present invention, the aerogel blanket may have a heat of combustion of 200 cal / g or less, more specifically 150 cal / g or less, 100 cal / g or less, or 70 cal / g or less, as measured by ISO 1716.

[0045] The aerogel blanket of the present invention has a much lower heat of combustion than conventional aerogel blankets, and therefore when exposed to high temperatures, the heat energy released upon combustion is low, minimizing heat generation and therefore exhibiting excellent heat insulation performance.

[0046] In the present invention, the aerogel blanket may have a compressibility of 15 to 30%, specifically 15 to 29%, or 16 to 28%, as determined by the following formula 3:

[0047] [Formula 3] Compression ratio (%) = [(Ta - Tb) / Ta] x 100 In the formula 3, Ta is the thickness of the aerogel blanket before compression (mm), Tb is the thickness (mm) of the aerogel blanket after 350 kPa compression.

[0048] Specifically, the compression ratio can be determined by preparing an aerogel blanket sample, for example, 10 cm x 10 cm, applying a pressure of 350 kPa to the sample using a UTM device, and then comparing the thickness before and after applying the pressure.

[0049] The aerogel blanket of the present invention exhibits excellent strength and compression resistance, and is able to exhibit the low compression ratio described above because it is less susceptible to thickness loss due to pressure.

[0050] In the present invention, the blanket substrate may be one or more selected from the group consisting of a film, a sheet, a net, a fiber, a porous material, a foam, and a nonwoven fabric, or may be a laminate of two or more layers of these materials.

[0051] In addition, the surface of the blanket substrate may be roughened or patterned depending on the intended use. Specifically, the blanket substrate may be a fiber having low thermal conductivity, which can further improve heat insulating performance by including spaces or voids in the blanket substrate that facilitate the insertion of sol and the formation of aerogel.

[0052] The blanket substrate may be specifically polyamide, polybenzimidazole, polyaramid, acrylic resin, phenolic resin, polyester, polyether ether ketone (PEEK), polyolefin (such as polyethylene, polypropylene, or copolymers thereof), cellulose, carbon, cotton, wool, hemp, nonwoven fabric, glass fiber, ceramic wool, basalt fiber, or ceramic paper, and more specifically may be inorganic fiber-based glass fiber, ceramic wool, basalt fiber, ceramic paper, or a combination thereof, but is not limited thereto.

[0053] The aerogel blanket of the present invention may be included in a heat insulating member, and the heat insulating member may be included in a battery.

[0054] The aerogel blanket of the present invention may be manufactured using the following manufacturing method.

[0055] Specifically, the first aspect includes the steps of: 1) preparing a sol containing a precursor material and a catalyst composition; 2) impregnating a blanket substrate with the sol and gelling it to produce a wet gel blanket; 3) surface-modifying the wet gel blanket; 4) drying the surface-modified wet gel blanket; and 5) heat-treating the wet gel blanket at a temperature of 450 to 650°C for 10 minutes to 6 hours.

[0056] A second aspect of the present invention includes the steps of: 1) preparing a sol containing a precursor material and a catalyst composition; 2) impregnating a blanket substrate with the sol and gelling it to produce a wet gel blanket; and 3) drying the wet gel blanket, wherein the blanket substrate is pretreated at a temperature of 400 to 500°C for 30 minutes to 2 hours. The second aspect of the present invention does not include the step of surface-modifying the wet gel blanket.

[0057] [First aspect] Step 1) The step 1) is a step of preparing a sol containing a precursor material and a catalyst composition, and the sol may be produced by mixing the precursor material and the catalyst composition.

[0058] According to one embodiment of the present invention, the sol in the present invention may be, for example, a silica sol, and when the sol is a silica sol, the precursor material may be a silica precursor.

[0059] In this case, the silica precursor may be a silicon-containing alkoxide-based compound, specifically, tetramethyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), methyl triethyl orthosilicate, dimethyl diethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetra secondary butyl orthosilicate, tetra tertiary butyl orthosilicate, tetrahexyl orthosilicate, tetracyclo ... The silica precursor may be a tetraalkyl silicate such as tetraethyl orthosilicate (TEOS) or tetradodecyl orthosilicate (tetradodecyl orthosilicate). More specifically, the silica precursor may be tetraethyl orthosilicate (TEOS), and in this case, the tetraethyl orthosilicate is preferably pre-hydrolyzed TEOS (HTEOS).

[0060] HTEOS is an ethyl polysilicate oligomer with a wide molecular weight distribution. When synthesized from TEOS monomer in the form of an oligomer, physical properties such as gelation time can be adjusted, making it easy to adapt to the user's reaction conditions. Another advantage is that it produces reproducible physical properties for the final product.

[0061] That is, HTEOS refers to a partially hydrated ethyl polysilicate oligomer, specifically, an oligomer derived from partially hydrated TEOS.

[0062] The silica precursor may be used in an amount such that the silica content in the silica sol is 0.1 wt % to 30 wt %, but is not limited thereto. When the silica content satisfies the above range, it is preferable in that the mechanical properties, particularly flexibility, of the aerogel blanket are ensured at an excellent level and the aerogel blanket has an improved heat insulating effect.

[0063] The catalyst composition may also include an organic solvent, water, and a base catalyst, where the base catalyst may include, but is not limited to, an inorganic base such as sodium hydroxide or potassium hydroxide; or an organic base such as ammonium hydroxide.

[0064] Specific examples of the organic base include ammonium hydroxide (NH4OH), tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), methylamine, ethylamine, isopropylamine, monoisopropylamine, diethylamine, diisopropylamine, dibutylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, choline, monoethanolamine, diethanolamine, 2-aminoethanol, 2-(ethylamino)ethanol, 2-(methylamino)ethanol, N-methyldiethanolamine, dimethylaminoethanol, diethylaminoethanol, nitrilotriethanol, 2-(2-aminoethoxy)ethanol, 1-amino-2-propanol, triethanolamine, monopropanolamine, and dibutanolamine, and mixtures of two or more of these may also be used. More specifically, the base catalyst may be NaOH.

[0065] The organic solvent may be, for example, an alcohol, such as a monohydric alcohol (e.g., methanol, ethanol, isopropanol, or butanol) or a polyhydric alcohol (e.g., glycerol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, or sorbitol), or a mixture of two or more of these. Considering miscibility with water and the aerogel, a monohydric alcohol having 1 to 6 carbon atoms, such as methanol, ethanol, isopropanol, or butanol, may be used.

[0066] The alcohol (polar organic solvent) as described above promotes the surface modification reaction, and may be used in an appropriate amount by a person skilled in the art, taking into consideration the degree of hydrophobicity in the finally produced aerogel.

[0067] According to one embodiment of the present invention, the catalyst composition may be included in an amount such that the pH of the sol is 4 to 8. When the pH of the sol is included so as to satisfy this range, gelation can be easily and efficiently carried out. In addition, since the catalyst composition is added in the form of a solution in which the base catalyst is diluted in water and an organic solvent, problems such as catalyst precipitation can be prevented.

[0068] Step 2) Step 2) is a step in which the sol is impregnated into a blanket substrate and gelled to produce a wet gel blanket.

[0069] In the present invention, gelation may be a process for forming a network structure from a precursor material, and the network structure may be a planar network structure in which certain polygons having one or more types of atomic arrangements are connected, or a structure in which vertices, corners, faces, etc. of certain polyhedra are shared to form a three-dimensional skeletal structure.

[0070] The gelation of the sol may be carried out in a state where the blanket substrate is impregnated with the sol.

[0071] The impregnation may be performed in a reaction vessel capable of accommodating the blanket substrate. The sol may be poured into the reaction vessel, or the blanket substrate may be placed in a reaction vessel containing the sol and immersed therein. In this case, the blanket substrate may be lightly pressed to enhance the bond between the blanket substrate and the sol, allowing for sufficient impregnation. The blanket substrate may then be pressed to a predetermined thickness with a certain pressure to remove excess sol, thereby shortening the subsequent drying time.

[0072] According to one embodiment of the present invention, the blanket substrate may be a film, sheet, net, fiber, porous material, foam, nonwoven fabric, or a laminate of two or more layers thereof. Furthermore, depending on the intended use, the surface may be roughened or patterned. Specifically, the blanket substrate may be a fiber that can further improve thermal insulation performance by including spaces or voids in the blanket substrate that facilitate aerogel formation, or a material with low thermal conductivity may be used.

[0073] The blanket substrate may be specifically polyamide, polybenzimidazole, polyaramid, acrylic resin, phenolic resin, polyester, polyether ether ketone (PEEK), polyolefin (such as polyethylene, polypropylene, or copolymers thereof), cellulose, carbon, cotton, wool, hemp, nonwoven fabric, glass fiber, ceramic wool, basalt fiber, or ceramic paper, and more specifically may be inorganic fiber-based glass fiber, ceramic wool, basalt fiber, or ceramic paper, but is not limited thereto.

[0074] After step 2), the method may further include a step of aging the wet gel blanket.

[0075] The aging step is a process in which the silica wet gel or silica wet gel blanket is left at an appropriate temperature to allow complete chemical change. An additional aging step may be performed, which can strengthen the network structure formed above, thereby enhancing the mechanical stability of the silica aerogel or silica aerogel blanket of the present invention.

[0076] The aging step of the present invention involves adding a solution of a basic catalyst, such as sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonium hydroxide (NH4OH), triethylamine, or pyridine, diluted to a concentration of 1-10% in an organic solvent to maximize Si-O-Si bonding in the aerogel, strengthening the silica gel network structure and making it easier to maintain the pore structure in the subsequent rapid drying process. In this case, the organic solvent may be the aforementioned alcohol (polar organic solvent), specifically, ethanol.

[0077] Furthermore, the aging step must be carried out within an appropriate temperature range to optimally strengthen the pore structure, and the aging step of the present invention may be carried out by leaving the mixture at a temperature of 30 to 70° C. for 1 to 24 hours. If the aging temperature is below 30° C., the aging time becomes excessively long, which increases the total process time and reduces productivity. On the other hand, if the aging temperature exceeds 70° C., the temperature is outside the boiling point of ethanol, which increases the loss of solvent due to evaporation and increases the cost of raw materials.

[0078] Step 3) Step 3) is a step of surface-modifying the wet gel blanket, and may be a step of hydrophobizing the wet gel blanket, particularly the silica wet gel blanket, with a surface modifier. Specifically, this can be achieved by bonding hydrophobic groups derived from the surface modifier to the surface of the silica wet gel.

[0079] Silica aerogel blankets have the drawback of absorbing water from the air due to the presence of silanol groups (Si-OH) on the silica surface, which are hydrophilic, gradually increasing their thermal conductivity. Therefore, to suppress absorption of water from the air and maintain low thermal conductivity, it is necessary to modify the silica aerogel surface to make it hydrophobic in advance.

[0080] The surface modifier of the present invention may be any compound that hydrophobicizes the wet gel surface, and may be, for example, a silane-based compound, a siloxane-based compound, a silanol-based compound, a silazane-based compound, or a combination thereof.

[0081] Specifically, trimethylchlorosilane (TMCS), dimethyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, trimethylethoxysilane, vinyltrimethoxysilane, ethyltriethoxysilane, phenyltriethoxysilane, phenyltrimethoxysilane, tetraethoxysilane, dimethyldichlorosilane, 3-aminopropyl Silane compounds including methyltriethoxysilane; siloxane compounds including polydimethylsiloxane, polydiethylsiloxane, or octamethylcyclotetrasiloxane; silanol compounds including trimethylsilanol, triethylsilanol, triphenylsilanol, and t-butyldimethylsilanol; 1,2-diethyldisilazane, 1,1,2,2-tetramethyldisilazane, and 1,1,3,3-tetramethyldisilazane. silazane-based compounds including 1,1,1,2,2,2-hexamethyldisilazane (HMDS), 1,1,2,2-tetraethyldisilazane, or 1,2-diisopropyldisilazane; or combinations thereof, specifically hexamethyldisilazane.

[0082] The surface modifier may be used in the form of a solution diluted in an organic solvent, which may be the alcohol (organic solvent) described in step 1), and in this case, the surface modifier may be diluted to 1 to 15% by volume based on the volume of the total diluted solution.

[0083] The surface modifier may be added in an amount of 0.01 to 10% by volume relative to the wet gel blanket. When the amount is within this range, the amount of the surface modifier is sufficient, resulting in excellent surface modification reactivity and easy surface modification, which in turn suppresses the condensation reaction of unmodified silanol groups during drying, resulting in superior porosity of the finally produced silica aerogel blanket.

[0084] The step 3) may be carried out at a temperature of 50 to 90°C, preferably 50 to 80°C, for 1 to 24 hours by adding a surface modifier.

[0085] Step 4) Step 4) is a step of drying the surface-modified wet gel blanket, which removes water and solvent from the wet gel blanket to produce an aerogel blanket.

[0086] Meanwhile, the manufacturing method according to one embodiment of the present invention may further include a washing step before the drying. The washing is for removing impurities (sodium ions, unreacted materials, by-products, etc.) generated during the reaction and residual ammonia, which may react with CO to generate ammonium carbonate salt during supercritical drying, to obtain a high-purity hydrophobic silica aerogel. The washing may be performed by a dilution process or an exchange process using a non-polar organic solvent.

[0087] The drying step according to an embodiment of the present invention may be performed by removing the solvent while maintaining the pore structure of the aged gel, and may be performed by supercritical drying or atmospheric drying.

[0088] The supercritical drying process may be performed using supercritical carbon dioxide. Carbon dioxide (CO2) is in a gaseous state at room temperature and pressure, but when it exceeds a certain temperature and pressure limit called the supercritical point, it enters a critical state where it cannot be distinguished between gas and liquid because the evaporation process does not occur. Carbon dioxide in this critical state is called supercritical carbon dioxide.

[0089] Supercritical carbon dioxide has molecular density close to that of a liquid, but low viscosity, making it similar to a gas. It also has fast diffusion and high thermal conductivity, resulting in high drying efficiency and shortening the drying process time.

[0090] Specifically, the supercritical drying process involves placing the matured wet gel blanket in a supercritical drying reactor, filling it with liquid CO2, and replacing the alcohol solvent inside the wet gel with CO2. The temperature is then raised to 40-70°C at a constant rate, specifically 0.1°C / min to 1°C / min, and a pressure above the pressure at which carbon dioxide reaches the supercritical state, specifically 100 bar to 150 bar, is maintained. The carbon dioxide reaches the supercritical state for a certain period, specifically 20 minutes to 1 hour. Carbon dioxide typically reaches the supercritical state at a temperature of 31°C and a pressure of 73.8 bar. After maintaining the temperature and pressure at which carbon dioxide reaches the supercritical state for 2 hours to 12 hours, more specifically 2 hours to 6 hours, the pressure is gradually released, completing the supercritical drying process and producing an aerogel blanket.

[0091] In the case of the atmospheric pressure drying step, the step may be carried out by a conventional method such as hot air drying or IR drying at a temperature of 70 to 200° C. under atmospheric pressure (1±0.3 atm).

[0092] As a result of the drying process, a blanket containing porous aerogel with nano-sized pores can be produced. In particular, the silica aerogel according to one embodiment of the present invention has a high degree of hydrophobicity and excellent physical properties, particularly low tap density and high porosity, and a silica aerogel-containing blanket containing the same has low thermal conductivity and excellent mechanical flexibility.

[0093] In addition, before or after the drying process, a pressing process for adjusting the thickness and making the internal structure and surface shape of the blanket uniform, a molding process for providing an appropriate shape or morphology depending on the application, or a lamination process for laminating another functional layer may be further performed.

[0094] Step 5) Step 5) is a step of heat treatment at a temperature of 450 to 650°C for 10 minutes to 6 hours, in which the aerogel blanket is exposed to high temperatures under certain conditions to remove organic matter.

[0095] By carrying out the heat treatment at this temperature, excessive shrinkage of silica due to excessively high temperature can be prevented, and organic matter can be sufficiently decomposed at an appropriately high temperature. If the temperature and time are within the above range, a person skilled in the art can carry out the heat treatment at an appropriate combination of temperature and time.

[0096] Furthermore, the heat treatment causes sintering of the silica in the aerogel blanket, thereby improving the strength of the aerogel blanket.

[0097] As described above, the aerogel blanket of the present invention has a low organic content of 1.2 wt % or less due to the removal of organic matter through the heat treatment process described above, and also exhibits high strength and a lower compressibility than conventional aerogel blankets.

[0098] [Second mode] Step 1) The step 1) is a step of preparing a sol containing a precursor material and a catalyst composition, and the sol may be produced by mixing the precursor material and the catalyst composition.

[0099] According to one embodiment of the present invention, the sol in the present invention may be, for example, a silica sol, and when the sol is a silica sol, the precursor material may be a silica precursor.

[0100] In this case, the silica precursor may be a silicon-containing alkoxide-based compound, specifically, tetramethyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), methyl triethyl orthosilicate, dimethyl diethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetra secondary butyl orthosilicate, tetra tertiary butyl orthosilicate, tetrahexyl orthosilicate, tetracyclo ... The silica precursor may be a tetraalkyl silicate such as tetraethyl orthosilicate (TEOS) or tetradodecyl orthosilicate (tetradodecyl orthosilicate). More specifically, the silica precursor may be tetraethyl orthosilicate (TEOS), and in this case, the tetraethyl orthosilicate is preferably pre-hydrolyzed TEOS (HTEOS).

[0101] HTEOS is an ethyl polysilicate oligomer with a wide molecular weight distribution. When synthesized from TEOS monomer in the form of an oligomer, physical properties such as gelation time can be adjusted, making it easy to adapt to the user's reaction conditions. Another advantage is that it produces reproducible physical properties for the final product.

[0102] That is, HTEOS refers to a partially hydrated ethyl polysilicate oligomer, specifically, an oligomer derived from partially hydrated TEOS.

[0103] The silica precursor may be used in an amount such that the silica content in the silica sol is 0.1 wt % to 30 wt %, but is not limited thereto. When the silica content satisfies the above range, it is preferable in that the mechanical properties, particularly flexibility, of the aerogel blanket are ensured at an excellent level and the aerogel blanket has an improved heat insulating effect.

[0104] The catalyst composition may also contain an organic solvent, water, and a base catalyst. In this case, the base catalyst may be an inorganic base such as sodium hydroxide or potassium hydroxide; or an organic base such as ammonium hydroxide. In the case of an inorganic base, however, an organic base is preferred because metal ions contained in the compound may be coordinated to the Si-OH compound.

[0105] Specific examples of the organic base include ammonium hydroxide (NH4OH), tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), methylamine, ethylamine, isopropylamine, monoisopropylamine, diethylamine, diisopropylamine, dibutylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, choline, monoethanolamine, diethanolamine, 2-aminoethanol, 2-(ethylamino)ethanol, 2-(methylamino)ethanol, N-methyldiethanolamine, dimethylaminoethanol, diethylaminoethanol, nitrilotriethanol, 2-(2-aminoethoxy)ethanol, 1-amino-2-propanol, triethanolamine, monopropanolamine, and dibutanolamine, and mixtures of two or more of these may also be used. More specifically, the base catalyst may be ammonium hydroxide (NH4OH).

[0106] The organic solvent may be, for example, an alcohol, such as a monohydric alcohol (e.g., methanol, ethanol, isopropanol, or butanol) or a polyhydric alcohol (e.g., glycerol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, or sorbitol), or a mixture of two or more of these. Considering miscibility with water and the aerogel, a monohydric alcohol having 1 to 6 carbon atoms, such as methanol, ethanol, isopropanol, or butanol, may be used.

[0107] The alcohol (polar organic solvent) as described above promotes the surface modification reaction, and may be used in an appropriate amount by a person skilled in the art, taking into consideration the degree of hydrophobicity in the finally produced aerogel.

[0108] According to one embodiment of the present invention, the catalyst composition may be included in an amount such that the pH of the sol is 4 to 8. When the pH of the sol is included so as to satisfy this range, gelation can be easily and efficiently carried out. In addition, since the catalyst composition is added in the form of a solution in which the base catalyst is diluted in water and an organic solvent, problems such as catalyst precipitation can be prevented.

[0109] Step 2) Step 2) is a step in which the sol is impregnated into a blanket substrate and gelled to produce a wet gel blanket.

[0110] In the present invention, the blanket substrate is pretreated at a temperature of 400 to 500° C. for 30 minutes to 2 hours. Generally, the blanket substrate contains a certain amount of organic matter, and the pretreatment is used to remove the organic matter contained in the blanket substrate before manufacturing the aerogel blanket.

[0111] By performing the pretreatment conditions within the above ranges, the organic matter in the blanket substrate can be removed, reducing the organic matter content in the final aerogel blanket, and the high-temperature heat insulation performance, strength, etc. of the aerogel blanket can be improved.

[0112] In the present invention, gelation may be a process for forming a network structure from a precursor material, and the network structure may be a planar network structure in which certain polygons having one or more types of atomic arrangements are connected, or a structure in which vertices, corners, faces, etc. of certain polyhedra are shared to form a three-dimensional skeletal structure.

[0113] The gelation of the sol may be carried out in a state where the blanket substrate is impregnated with the sol.

[0114] The impregnation may be performed in a reaction vessel capable of accommodating the blanket substrate. The sol may be poured into the reaction vessel, or the blanket substrate may be placed in a reaction vessel containing the sol and immersed therein. In this case, the blanket substrate may be lightly pressed to enhance the bond between the blanket substrate and the sol, allowing for sufficient impregnation. The blanket substrate may then be pressed to a predetermined thickness with a certain pressure to remove excess sol, thereby shortening the subsequent drying time.

[0115] According to one embodiment of the present invention, the blanket substrate may be a film, sheet, net, fiber, porous material, foam, nonwoven fabric, or a laminate of two or more layers thereof. Furthermore, depending on the intended use, the surface may be roughened or patterned. Specifically, the blanket substrate may be a fiber that can further improve thermal insulation performance by including spaces or voids in the blanket substrate that facilitate aerogel formation, or a material with low thermal conductivity may be used.

[0116] Specifically, the blanket substrate may be polyamide, polybenzimidazole, polyaramid, acrylic resin, phenolic resin, polyester, polyether ether ketone (PEEK), polyolefin (such as polyethylene, polypropylene, or copolymers thereof), cellulose, carbon, cotton, wool, hemp, nonwoven fabric, glass fiber, or ceramic wool.

[0117] After step 2), the method may further include a step of aging the wet gel blanket.

[0118] The aging step is a process in which the silica wet gel or silica wet gel blanket is left at an appropriate temperature to allow complete chemical change. An additional aging step may be performed, which can strengthen the network structure formed above, thereby enhancing the mechanical stability of the silica aerogel or silica aerogel blanket of the present invention.

[0119] The aging step of the present invention involves adding a solution of a basic catalyst, such as sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonium hydroxide (NH4OH), triethylamine, or pyridine, diluted to a concentration of 1-10% in an organic solvent to maximize Si-O-Si bonding in the aerogel, strengthening the silica gel network structure and making it easier to maintain the pore structure in the subsequent rapid drying process. In this case, the organic solvent may be the aforementioned alcohol (polar organic solvent), specifically, ethanol.

[0120] Furthermore, the aging step must be carried out within an appropriate temperature range to optimally strengthen the pore structure, and the aging step of the present invention may be carried out by leaving the mixture at a temperature of 30 to 70° C. for 1 to 10 hours. If the aging temperature is less than 30° C., the aging time becomes excessively long, which increases the total process time and reduces productivity. On the other hand, if the aging temperature exceeds 70° C., the temperature is outside the boiling point of ethanol, which increases the loss of solvent due to evaporation and increases the cost of raw materials.

[0121] On the other hand, the second embodiment does not include a step of surface-modifying the wet gel blanket. When aerogel blankets are manufactured using conventional techniques, a surface-modification step is generally performed to replace hydroxyl groups on the wet gel blanket surface with methyl groups, which makes the aerogel surface hydrophobic. However, this process has the problem of increasing the organic content of the aerogel blanket.

[0122] Therefore, in the second aspect of the present invention, the increase in the organic content is prevented by not carrying out surface modification.

[0123] Step 3) Step 3) is a step of drying the wet gel blanket, which removes the water and solvent in the wet gel blanket to produce an aerogel blanket.

[0124] Meanwhile, the manufacturing method according to one embodiment of the present invention may further include a washing step before the drying. The washing is for removing impurities (sodium ions, unreacted materials, by-products, etc.) generated during the reaction and residual ammonia, which may react with CO to generate ammonium carbonate salt during supercritical drying, to obtain a high-purity hydrophobic silica aerogel. The washing may be performed by a dilution process or an exchange process using a non-polar organic solvent.

[0125] The drying step according to an embodiment of the present invention may be performed by removing the solvent while maintaining the pore structure of the aged gel, and may be performed by supercritical drying or atmospheric drying.

[0126] The supercritical drying process may be performed using supercritical carbon dioxide. Carbon dioxide (CO2) is in a gaseous state at room temperature and pressure, but when it exceeds a certain temperature and pressure limit called the supercritical point, it enters a critical state where it cannot be distinguished between gas and liquid because the evaporation process does not occur. Carbon dioxide in this critical state is called supercritical carbon dioxide.

[0127] Supercritical carbon dioxide has molecular density close to that of a liquid, but low viscosity, making it similar to a gas. It also has fast diffusion and high thermal conductivity, resulting in high drying efficiency and shortening the drying process time.

[0128] Specifically, the supercritical drying process involves placing the matured wet gel blanket in a supercritical drying reactor, filling it with liquid CO2, and replacing the alcohol solvent inside the wet gel with CO2. The temperature is then raised to 40-70°C at a constant rate, specifically 0.1°C / min to 1°C / min, and a pressure above the pressure at which carbon dioxide reaches the supercritical state, specifically 100 bar to 150 bar, is maintained. The carbon dioxide reaches the supercritical state for a certain period, specifically 20 minutes to 1 hour. Carbon dioxide typically reaches the supercritical state at a temperature of 31°C and a pressure of 73.8 bar. After maintaining the temperature and pressure at which carbon dioxide reaches the supercritical state for 2 hours to 12 hours, more specifically 2 hours to 6 hours, the pressure is gradually released, completing the supercritical drying process and producing an aerogel blanket.

[0129] In the case of the atmospheric pressure drying step, the step may be carried out by a conventional method such as hot air drying or IR drying at a temperature of 70 to 200° C. under atmospheric pressure (1±0.3 atm).

[0130] As a result of the drying process, a blanket containing porous aerogel with nano-sized pores can be produced. In particular, the silica aerogel according to one embodiment of the present invention has a high degree of hydrophobicity and excellent physical properties, particularly low tap density and high porosity, and a silica aerogel-containing blanket containing the same has low thermal conductivity and excellent mechanical flexibility.

[0131] In addition, before or after the drying process, a pressing process for adjusting the thickness and making the internal structure and surface shape of the blanket uniform, a molding process for providing an appropriate shape or morphology depending on the application, or a lamination process for laminating another functional layer may be further performed.

[0132] Example The present invention will be described in more detail below with reference to examples. However, the following examples are for illustrative purposes only and the scope of the present invention is not limited to these examples.

[0133] Example 1 Tetraethyl orthosilicate (TEOS) and water were mixed in a 1:4 molar ratio, and ethanol was added in a 1:1 weight ratio to the TEOS to prepare a silica precursor solution. To promote hydrolysis of the silica precursor solution, acid was added to adjust the pH of the silica precursor solution to 3 or less, and the mixture was stirred for at least two hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a 1:4 weight ratio to the hydrated TEOS solution. 100 parts by weight of the silica sol was mixed with 0.2 parts by weight of TiO2 (an opacifying agent) and Ultracarb (LKAB) (a flame retardant) and stirred for 30 minutes. A catalyzed sol was prepared by adding a base catalyst solution (5 wt % NaOH aqueous solution) in a 99:1 volume ratio to the silica sol.

[0134] The catalyzed sol was impregnated into fibers and gelled. After gelation was complete, the wet gel blanket was recovered from the reaction vessel and aged in a 10 wt% TMES solution at 60°C for 16 hours to perform surface modification. The wet gel blanket was then placed in a supercritical extractor, CO2 was injected, and the temperature inside the extractor was raised to 60°C over 1 hour, followed by supercritical drying at 60°C and 150 bar.

[0135] After drying was completed, the aerogel blanket was obtained by heat treatment for 10 minutes in an electric furnace at 650°C in a general air atmosphere.

[0136] Examples 2 to 5 An aerogel blanket was manufactured in the same manner as in Example 1, except that the temperature and time conditions of the heat treatment were changed as shown in Table 1 below.

[0137] Example 6 Tetraethyl orthosilicate (TEOS) and water were mixed in a 1:4 molar ratio, and ethanol was added in a 1:1 weight ratio to the TEOS to prepare a silica precursor solution. To promote hydrolysis of the silica precursor solution, acid was added to adjust the pH of the silica precursor solution to 3 or less, and the mixture was stirred for at least two hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a 1:4 weight ratio to the hydrated TEOS solution. 100 parts by weight of the silica sol was mixed with 0.2 parts by weight of TiO2 (an opacifying agent) and Ultracarb (LKAB) (a flame retardant) and stirred for 30 minutes. A catalyzed sol was prepared by adding a base catalyst solution (5 wt % NaOH aqueous solution) in a 99:1 volume ratio to the silica sol.

[0138] Meanwhile, the prepared fibers were heat-treated in an electric furnace at 450°C in a general air atmosphere for 1 hour.

[0139] The catalyzed sol was then impregnated into the heat-treated fibers for gelation. The wet gel blanket was then placed in a supercritical extractor without any additional surface modification step, and CO2 was injected. The temperature in the extractor was raised to 60°C over 1 hour, and supercritical drying was performed at 60°C and 150 bar.

[0140] Comparative Example 1 Tetraethyl orthosilicate (TEOS) and water were mixed in a 1:4 molar ratio, and ethanol was added in a 1:1 weight ratio to the TEOS to prepare a silica precursor solution. To promote hydrolysis of the silica precursor solution, acid was added to adjust the pH of the silica precursor solution to 3 or less, and the mixture was stirred for at least two hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a 1:4 weight ratio to the hydrated TEOS solution. 100 parts by weight of the silica sol was mixed with 0.2 parts by weight of TiO2 (an opacifying agent) and Ultracarb (LKAB) (a flame retardant) and stirred for 30 minutes. A catalyzed sol was prepared by adding a base catalyst solution (5 wt % NaOH aqueous solution) in a 99:1 volume ratio to the silica sol.

[0141] The catalyzed sol was impregnated into fibers and gelled. After gelation was complete, the wet gel blanket was recovered from the reaction vessel and aged in a 10 wt% TMES solution at 60°C for 16 hours to perform surface modification. The wet gel blanket was then placed in a supercritical extractor, CO2 was injected, and the temperature inside the extractor was raised to 60°C over 1 hour, followed by supercritical drying at 60°C and 150 bar.

[0142] Comparative Examples 2 and 4 An aerogel blanket was manufactured in the same manner as in Example 1, except that the temperature and time conditions of the heat treatment were changed as shown in Table 1 below.

[0143] Comparative Example 3 Tetraethyl orthosilicate (TEOS) and water were mixed in a 1:4 molar ratio, and ethanol was added in a 1:1 weight ratio to the TEOS to prepare a silica precursor solution. To promote hydrolysis of the silica precursor solution, acid was added to adjust the pH of the silica precursor solution to 3 or less, and the mixture was stirred for at least two hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a 1:4 weight ratio to the hydrated TEOS solution. 100 parts by weight of the silica sol was mixed with 0.2 parts by weight of TiO2 (an opacifying agent) and Ultracarb (LKAB) (a flame retardant) and stirred for 30 minutes. A catalyzed sol was prepared by adding a base catalyst solution (5 wt % NaOH aqueous solution) in a 99:1 volume ratio to the silica sol.

[0144] Meanwhile, the prepared fibers were heat-treated in an electric furnace at 450°C in a general air atmosphere for 1 hour.

[0145] The catalyzed sol was impregnated into heat-treated fibers to cause gelation. After gelation was completed, the wet gel blanket was recovered from the reaction vessel and aged in a 10 wt% TMES solution at 60°C for 16 hours to perform surface modification. The wet gel blanket was placed in a supercritical extractor, CO2 was injected, and the temperature inside the extractor was raised to 60°C over 1 hour, followed by supercritical drying at 60°C and 150 bar.

[0146] [Table 1]

[0147] Experimental Example 1: Organic matter content The weight (Wa) of a 10cm x 10cm aerogel blanket sample was measured, and then it was heat-treated at 600°C for 12 hours or more in a normal air atmosphere to remove all organic matter, and the weight (Wb) was then measured. Finally, the organic matter content was calculated using the following equation 1.

[0148] [Formula 1] Organic matter content (wt%)=[(Wa-Wb) / Wa]×100

[0149] [Table 2]

[0150] As shown in Table 2, it was confirmed that the aerogel blanket according to the present invention had a low organic content of less than 2.0 wt %, while the organic contents of Comparative Examples 1 to 4 all exceeded 2.0 wt %.

[0151] This is because in Examples 1 to 6, the residual organic matter content of the aerogel blanket was reduced by performing high-temperature heat treatment conditions during the production of the aerogel blanket, or by using pretreated fibers without performing surface modification.

[0152] Experimental Example 2: Room temperature thermal conductivity Using 30 cm x 30 cm samples of the silica aerogel blankets manufactured in the examples and comparative examples, the thermal conductivity at room temperature (20±5°C) was measured using a NETZSCH HFM 436 device.

[0153] [Table 3]

[0154] As shown in Table 3, the aerogel blanket according to the embodiment of the present invention maintains a normal level of thermal conductivity despite being manufactured through a high-temperature heat treatment process, and exhibits higher thermal conductivity and better high-temperature heat shielding performance than the comparative example.

[0155] Experimental example 3: High temperature heat blocking performance A 3 mm thick sample of the silica aerogel blanket prepared in the Examples and Comparative Examples was prepared in a 10 cm x 10 cm size. The upper heating plate was heated to 650°C. The measurement sample was placed on the lower sample plate equipped with a thermocouple, and the height was adjusted so that the heating plate contacted the top of the sample. The temperature of the bottom end of the sample (rear temperature) and the time immediately after contact were recorded, and the time (sec) required for the temperature to reach 180°C was measured.

[0156] [Table 4]

[0157] As shown in Table 4, it was confirmed that the aerogel blanket according to the embodiment of the present invention has excellent heat insulating performance at high temperatures, and takes a longer time to reach 180°C than the comparative example.

[0158] Experimental Example 4: Compression Resistance The silica aerogel blanket samples prepared in the examples and comparative examples were prepared in a size of 10 cm x 10 cm, and their thickness (Ta) was measured. A pressure of 350 kPa was applied to the sample using a UTM device, and the compressed thickness (Tb) was measured. The compression ratio (%) was calculated by dividing the difference between the initial thickness and the compressed thickness by the initial thickness using the following equation 3.

[0159] [Formula 3] Compression ratio (%) = [(Ta - Tb) / Ta] x 100

[0160] [Table 5]

[0161] As shown in Table 5 above, it was confirmed that the aerogel blanket according to the embodiment of the present invention had improved strength after heat treatment, reduced thickness reduction rate (compression rate) during compression, and improved compression resistance.

[0162] Experimental Example 5: Moisture impregnation rate In accordance with ASTM C1511, a test piece with a size of 25.4 cm × 25.4 cm was floated on distilled water at 21 ± 2°C, a 6.4 mm mesh screen was placed on the test piece, and it was submerged to 127 mm below the water surface. After 15 minutes, when the screen was removed and the test piece floated, the test piece was picked up with a clamp and hung vertically for 60 ± 5 seconds, and then the weights before and after impregnation were measured respectively to confirm the weight increase rate, which was shown as the moisture impregnation rate.

[0163] [Table 6]

[0164] As shown in Table 6 above, it was confirmed that the aerogel blanket of the present invention had a low organic matter content, a low degree of hydrophobicity, and a high moisture impregnation rate.

[0165] Experimental Example 6: Pore distribution 0.1 g of an aerogel blanket sample was placed in a BET专用 glass bottle, connected to a pretreatment device, and then pretreated at 150°C for 12 hours while reducing the pressure from 1 to 760 Torr to remove impurities including moisture in the sample. The pore distribution of the pretreated sample was analyzed using a 3 FLEX device (Micrometrics) by the adsorption / desorption amount of nitrogen at a partial pressure (0.11 < p / p0 < 1) and is shown in Figure 1.

[0166] As shown in Figure 1, the aerogel of Comparative Example 1 had a pore diameter of less than 10 nm, while the aerogel of Example 1 had an overall larger pore size and a wider distribution due to the sintering of the aerogel.

[0167] Experimental Example 7: Measurement of combustion heat The heat of combustion was measured according to the ISO 1716 measurement standard.

[0168] [Table 7]

[0169] As shown in Table 7, the Examples showed a much lower level of heat of combustion than the Comparative Examples, which indicates that when the aerogel blanket of the present invention is exposed to high temperatures, heat generation is reduced and the blanket has excellent high-temperature heat insulation performance.

Claims

1. aerogel and a blanket substrate, An aerogel blanket having an organic content of 1.2 wt % or less according to the following formula 1: [Formula 1] Organic matter content (wt%) = [(Wa-Wb) / Wa] x 100 In the formula 1, Wa is the weight (g) of the aerogel blanket before heat treatment; Wb is the weight (g) of the aerogel blanket after heat treatment at 600°C for 12 hours.

2. 2. The aerogel blanket of claim 1, wherein the organic material is at least one selected from the group consisting of a hydrophobic group bonded to the aerogel, a binder, and a sizing agent.

3. 2. The aerogel blanket according to claim 1, wherein the aerogel blanket has a room temperature thermal conductivity of 15 mW / mK or more and 35 mW / mK or less.

4. 10. The aerogel blanket of claim 1, wherein the aerogel contains pores having a diameter of 10 nm or more and 50 nm or less.

5. 2. The aerogel blanket according to claim 1, wherein the blanket substrate is at least one selected from the group consisting of a film, a sheet, a net, a fiber, a porous body, a foam, and a nonwoven fabric body.

6. 6. The aerogel blanket according to claim 5, wherein the blanket substrate is at least one selected from the group consisting of glass fiber, ceramic wool, basalt fiber, and ceramic paper.

7. 2. The aerogel blanket according to claim 1, wherein the aerogel blanket has a water absorption rate of 100% by weight or more according to the following formula 2: [Formula 2] Water impregnation rate (wt%) = [(Wc - Wd) / Wd] x 100 In the formula 2, Wc is the weight (g) of the aerogel blanket after immersion in distilled water at 21±2°C for 15 minutes; Wd is the weight (g) of the aerogel blanket before immersion in distilled water.

8. 10. The aerogel blanket of claim 1, wherein the aerogel blanket has a heat of combustion of 200 cal / g or less as measured by ISO 1716.

9. 1) providing a sol containing precursor materials and a catalyst composition; 2) impregnating a blanket substrate with the sol to gel it, thereby producing a wet gel blanket; 3) surface modifying the wet gel blanket; 4) drying the surface-modified wet gel blanket; 5) heat treating at a temperature of 450 to 650°C for 10 minutes or more and 6 hours or less; A method for producing an aerogel blanket, comprising:

10. A heat insulating member comprising the aerogel blanket according to any one of claims 1 to 8.

11. A battery comprising the heat insulating member according to claim 10.

12. aerogel and a blanket substrate, An aerogel blanket having a compression rate of 15 to 30% according to the following formula 3. [Formula 3] Compression rate (%) = [(Ta - Tb) / Ta] x 100 In the formula 3, Ta is the thickness of the aerogel blanket before compression (mm); Tb is the thickness (mm) of the aerogel blanket after being compressed to 350 kPa.

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