Aerogel fiber mat and method of making

Abstract

The application discloses an aerogel fiber felt and a preparation method thereof. The method comprises the following steps: providing a fiber felt, placing a plurality of interval-arranged placeholder molds on the fiber felt, pouring a molding agent into the placeholder molds to form interval-arranged pre-placeholders on the fiber felt, filling an aerogel slurry into gaps between adjacent pre-placeholders, drying after sufficient solidification, removing the molding agent in the pre-placeholders, and taking out the placeholder molds from the fiber felt to obtain the aerogel fiber felt. The aerogel is used as a main material and is combined with the fiber felt, the process can ensure that the components are tightly combined, the aerogel fiber felt has better stability during transportation and use, the tensile and compressive strength of the material is increased, the possibility of particle falling and powder dropping is reduced, the composite strength of the aerogel fiber felt is greatly expanded, and the application range of the aerogel fiber felt is greatly expanded, and the aerogel fiber felt is beneficial to mass production and commercialization.

Description

Technical Field

[0001] This invention relates to the field of thermal insulation materials, and in particular to an aerogel fiber felt and its preparation method. Background Technology

[0002] Aerogel is a three-dimensional nanoporous material with ultra-high porosity. The nanoporous structure has a variety of physical properties, such as low refractive index, low thermal conductivity, low dielectric constant, and low acoustic impedance. It is widely used in various fields such as aerospace, thermal insulation and sound insulation, adsorption catalysis, and energy storage, with thermal insulation being the most common application.

[0003] With the continuous adjustment of my country's industrial structure, the new energy battery industry has emerged and developed, becoming one of the strategic emerging industries for the country's future development. Electric vehicles, as the mainstay of the new energy battery industry, experience accelerated battery performance degradation in low-temperature environments, severely impacting their driving range and power. Furthermore, low temperatures make battery charging difficult and threaten battery lifespan and safety. Considering the significant heat generated by the battery during charging and discharging, effectively insulating the battery by storing this heat can reduce energy consumption and maximize energy recycling. Therefore, the development and application of high-efficiency battery insulation materials are crucial for the promotion of electric vehicles in cold regions. Batteries also face high-temperature challenges such as fire and explosion prevention after accidents. Therefore, developing an effective aerogel composite fiber felt material is particularly important for the promotion of the new energy industry.

[0004] In existing technologies, aerogel fiber felts are prone to powder shedding and have low composite strength, which is not conducive to mass production and commercialization. Summary of the Invention

[0005] In view of the above situation, it is necessary to provide an aerogel fiber felt and its preparation method to address the problems of easy powder shedding and low composite strength of existing aerogel fiber felts.

[0006] A method for preparing an aerogel fiber mat, the method comprising:

[0007] A fiber mat is provided, on which a plurality of prefabricated placeholders are placed at intervals;

[0008] The molding agent is poured into the prefabricated spacer mold to form spaced pre-spacers on the fiber felt;

[0009] The aerogel slurry is filled into the gap between adjacent pre-occupied spaces, and after full curing, it is dried.

[0010] Remove the molding agent from the pre-placement and take out the pre-made placeholder mold from the fiber felt to obtain the aerogel fiber felt.

[0011] This invention uses aerogel as the main material, which is combined with fiber felt. This composite process ensures a tight bond between the components, resulting in better stability during transportation and use, increasing the tensile and compressive strength of the material, and reducing the possibility of particle shedding and powdering. A molding agent and aerogel are used to fill the fiber felt in an intermittent arrangement. After removing the pre-positioned spaces, gaps remain on the fiber felt, allowing it to be bent and folded. The aerogel filling the fiber felt forms the basis for insulation. During use, the gaps left by the pre-positioned spaces allow the fiber felt to be bent or folded, fully wrapping around products requiring heat insulation or thermal insulation. The composite strength of the aerogel and fiber felt also greatly expands its application range, making it more suitable for mass production and commercialization.

[0012] Furthermore, the preparation method of the aerogel slurry is as follows:

[0013] Add the dispersant to water and stir thoroughly to obtain a dispersion.

[0014] Inorganic silica aerogel particles were added to the dispersion and stirred thoroughly to obtain a primary aerogel slurry.

[0015] The adhesive is added to the primary aerogel slurry and stirred thoroughly to obtain the secondary aerogel slurry; the curing agent is added to the secondary aerogel slurry and stirred thoroughly to obtain the aerogel slurry.

[0016] Furthermore, the fiber felt is one of basalt fiber, glass fiber, ceramic fiber, and carbon fiber, with basalt fiber felt being preferred, and its bulk density being less than 0.15 g / cm³. 3 Preferably, the molding agent is one of paraffin wax, asphalt, and rosin.

[0017] Furthermore, the pre-occupied section is rectangular, the width of the pre-occupied section is 0.1mm to 1mm, the thickness of the pre-occupied section is 0.1mm to 1mm, and the interval between the pre-occupied sections is 2mm to 8mm.

[0018] Furthermore, the pre-occupied space can be formed in one or more layers along the vertical direction, with the pre-occupied spaces of the multiple layers arranged in parallel along the vertical direction, and the pre-occupied spaces of adjacent layers arranged in an alternating manner and not connected to each other.

[0019] Furthermore, the filling method of the aerogel slurry includes one of impregnation, spraying, and coating, and the drying treatment includes one of supercritical drying, environmental drying, freeze drying, and pinhole drying.

[0020] Furthermore, the method of removing the molding agent includes one of the following: high-temperature standing, blowing, and solvent replacement.

[0021] Furthermore, the dispersant is one of sodium oleate, sulfate ester salt, and sulfonate; the adhesive is one of polyvinyl alcohol, silicate, nitrate, borate, and polyvinylidene fluoride; and the curing agent is one of magnesium oxide and calcium aluminate.

[0022] Furthermore, the method for preparing the aforementioned aerogel fiber felt,

[0023] The molar ratio of the dispersant to water is (0.02mol~0.1mol):1mol, and the stirring rate of the dispersant added to the water is 800r / min~5000r / min;

[0024] The inorganic silica aerogel particles account for 10% to 20% of the mass fraction of the primary aerogel slurry, and the inorganic silica aerogel particles are added to the dispersion at a stirring rate of 300 r / min to 500 r / min.

[0025] The adhesive accounts for 1% to 10% of the mass fraction of the secondary aerogel slurry, and the adhesive is added to the primary aerogel slurry at a stirring rate of 200 r / min to 600 r / min.

[0026] The curing agent accounts for 0.1% to 1% of the mass fraction of the aerogel slurry. The curing agent is added to the secondary aerogel slurry at a stirring rate of 500 r / min to 700 r / min.

[0027] The present invention also provides an aerogel fiber felt prepared by the preparation method described above. Attached Figure Description

[0028] Figure 1 This is a flow chart of the aerogel fiber felt preparation process of the present invention;

[0029] Figure 2 This is a flow chart of the aerogel slurry preparation process of the present invention;

[0030] Figure 3 This is an overall structural diagram of the aerogel fiber felt according to the first embodiment of the present invention;

[0031] Figure 4 This is an overall structural diagram of the aerogel fiber felt according to the second embodiment of the present invention;

[0032] Figure 5 This is a state diagram of the present invention during use;

[0033] Figure 6 for Figure 5 Enlarged view of point A in the middle. Detailed Implementation

[0034] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0035] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Furthermore, the various embodiments of the invention, the features within those embodiments, and the features of the embodiments may be freely combined without obvious conflict or contradiction.

[0037] Example 1

[0038] See 1 to Figure 3 As shown, a method for preparing an aerogel fiber mat includes steps S1 to S4:

[0039] S1: A fiber felt is provided, on which a plurality of prefabricated placeholders are placed at intervals;

[0040] Specifically, the fiber felt is made of basalt fiber with a bulk density of 0.1 g / cm³. 3 Multiple prefabricated placeholder molds are placed at intervals on the fiber felt.

[0041] S2: The molding agent is poured into the prefabricated occupant mold to form pre-occupants arranged at intervals on the fiber felt;

[0042] Specifically, the molding agent is paraffin wax, the cross-sectional width of the pre-occupied space is 0.1 mm, the thickness of the pre-occupied space is 0.5 mm, the spacing of the pre-occupied spaces is 2 mm, and the pre-occupied space is formed in a single layer along the vertical direction.

[0043] S3: Fill the gap between adjacent pre-occupied spaces with aerogel slurry, and after full curing, perform drying treatment to obtain primary aerogel fiber felt.

[0044] Specifically, the aerogel slurry is filled by impregnation and dried using supercritical fluid extraction.

[0045] S4: Remove the molding agent from the pre-positioned space and take out the spacer mold from the fiber felt to obtain an aerogel fiber felt.

[0046] Specifically, the method for removing the molding agent is to allow it to stand at high temperature.

[0047] Before step S3, steps S11 to S14 are also included:

[0048] S11: Add the dispersant to the aqueous solution and stir thoroughly to obtain a dispersion;

[0049] Specifically, the dispersant is sodium oleate, the molar ratio of sodium oleate to water is 0.05 mol: 1 mol, and the stirring rate is 2000 r / min.

[0050] S12: Add inorganic silica aerogel particles to the dispersion and stir thoroughly to obtain a primary aerogel slurry;

[0051] Specifically, the aerogel particles account for 12% of the mass fraction of the primary aerogel slurry, and the stirring rate is 380 r / min.

[0052] S13: Add the adhesive to the primary aerogel slurry and stir thoroughly to obtain the secondary aerogel slurry;

[0053] Specifically, the adhesive is polyvinyl alcohol, which accounts for 6% of the mass fraction of the secondary aerogel slurry, and the stirring rate is 350 r / min.

[0054] S14: Add the curing agent to the secondary aerogel slurry and stir thoroughly to obtain the aerogel slurry.

[0055] Specifically, the curing agent is magnesium oxide, which accounts for 0.5% of the mass fraction of the aerogel slurry, and the stirring rate is 500 r / min.

[0056] Example 2

[0057] The preparation method in this embodiment is basically the same as that in Example 1, except that:

[0058] See Figure 1 , Figure 2 and Figure 4 As shown, in step S2, the molding agent is asphalt, the cross-sectional width of the pre-occupied space is 0.5mm, the thickness of the pre-occupied space is 0.8mm, the interval between the pre-occupied spaces is 6mm, and the pre-occupied spaces are arranged in parallel along the vertical direction to form two layers, with the pre-occupied spaces of the two layers being staggered and not connected to each other.

[0059] In step S3, the aerogel slurry is filled by coating and dried by environmental drying.

[0060] In step S4, the molding agent is removed by blowing.

[0061] In step S11, the dispersant is a sulfate salt, the molar ratio of sulfate salt to water is 0.02 mol: 1 mol, and the stirring rate is 800 r / min.

[0062] In step S12, the aerogel particles account for 20% of the mass fraction of the primary aerogel slurry, and the stirring rate is 500 r / min.

[0063] In step S13, the adhesive is a nitrate-based adhesive, and the nitrate-based adhesive accounts for 1% of the mass fraction of the secondary aerogel slurry. The stirring rate is 200 r / min.

[0064] In step S14, the curing agent is magnesium oxide, which accounts for 1% of the mass fraction of the aerogel slurry, and the stirring rate is 660 r / min.

[0065] Example 3

[0066] The preparation method in this embodiment is basically the same as that in Example 1, except that:

[0067] In step S1, the fiber felt is carbon fiber.

[0068] In step S2, the molding agent is rosin, the cross-sectional width of the pre-occupied space is 0.8 mm, the thickness of the pre-occupied space is 1 mm, the spacing of the pre-occupied spaces is 3 mm, and the pre-occupied spaces form a layer in the vertical direction.

[0069] In step S3, the aerogel slurry is filled by spraying and dried by freeze drying.

[0070] In step S4, the molding agent is removed by solvent replacement.

[0071] In step S11, the dispersant is a sulfonate, the molar ratio of sulfonate to water is 0.08 mol: 1 mol, and the stirring rate is 2500 r / min.

[0072] In step S12, the aerogel particles account for 15% of the mass fraction of the primary aerogel slurry, and the stirring rate is 300 r / min.

[0073] In step S13, the adhesive is a borate, and the borate accounts for 8% of the mass fraction of the secondary aerogel slurry. The stirring rate is 500 r / min.

[0074] In step S14, the curing agent is calcium aluminate, which accounts for 0.1% of the mass fraction of the aerogel slurry, and the stirring rate is 600 r / min.

[0075] Example 4

[0076] The preparation method in this embodiment is basically the same as that in Example 1, except that:

[0077] In step S1, the fiber felt is made of glass fiber.

[0078] In step S2, the molding agent is asphalt, the cross-sectional width of the pre-occupied space is 0.6 mm, the thickness of the pre-occupied space is 0.3 mm, the interval of the pre-occupied space is 5 mm, and the pre-occupied space is formed in a layer along the vertical direction.

[0079] In step S3, the aerogel slurry is filled by coating and dried by pinhole drying.

[0080] In step S4, the molding agent is removed by blowing.

[0081] In step S11, the dispersant is a sulfonate, the molar ratio of sulfonate to water is 0.03 mol: 1 mol, and the stirring rate is 800 r / min.

[0082] In step S12, the aerogel particles account for 10% of the mass fraction of the primary aerogel slurry, and the stirring rate is 320 r / min.

[0083] In step S13, the adhesive is polyvinylidene fluoride (PVDF), which accounts for 5% of the mass fraction of the secondary aerogel slurry, and the stirring rate is 380 r / min.

[0084] In step S14, the curing agent is calcium aluminate, which accounts for 0.6% of the mass fraction of the aerogel slurry, and the stirring rate is 700 r / min.

[0085] Example 5

[0086] The preparation method in this embodiment is basically the same as that in Example 1, except that:

[0087] In step S1, the fiber felt is ceramic fiber.

[0088] In step S2, the molding agent is rosin, the cross-sectional width of the pre-occupied space is 0.8 mm, the thickness of the pre-occupied space is 0.1 mm, the spacing of the pre-occupied spaces is 3 mm, the pre-occupied spaces form a layer in the vertical direction, and the pre-occupied spaces of adjacent layers are staggered and not connected to each other.

[0089] In step S3, the aerogel slurry is filled by spraying and dried by freeze drying.

[0090] In step S4, the molding agent is removed by solvent replacement.

[0091] In step S11, the dispersant is a sulfonate, the molar ratio of sulfonate to water is 0.08 mol: 1 mol, and the stirring rate is 2500 r / min.

[0092] In step S12, the aerogel particles account for 15% of the mass fraction of the primary aerogel slurry, and the stirring rate is 300 r / min.

[0093] In step S13, the adhesive is a borate, and the borate accounts for 8% of the mass fraction of the secondary aerogel slurry. The stirring rate is 500 r / min.

[0094] In step S14, the curing agent is calcium aluminate, which accounts for 0.1% of the mass fraction of the aerogel slurry, and the stirring rate is 600 r / min.

[0095] Example 6

[0096] The preparation method in this embodiment is basically the same as that in Example 1, except that:

[0097] In step S1, the fiber felt is carbon fiber.

[0098] In step S2, the molding agent is rosin, the cross-sectional width of the pre-occupied space is 0.8 mm, the thickness of the pre-occupied space is 0.6 mm, the spacing of the pre-occupied spaces is 3 mm, and the pre-occupied space is formed in a layer along the vertical direction.

[0099] In step S3, the aerogel slurry is filled by spraying and dried by freeze drying.

[0100] In step S4, the molding agent is removed by solvent replacement.

[0101] In step S11, the dispersant is a sulfonate, the molar ratio of sulfonate to water is 0.05 mol: 1 mol, and the stirring rate is 2300 r / min.

[0102] In step S12, the aerogel particles account for 13% of the mass fraction of the primary aerogel slurry, and the stirring rate is 360 r / min.

[0103] In step S13, the adhesive is a borate, and the borate accounts for 5% of the mass fraction of the secondary aerogel slurry. The stirring rate is 450 r / min.

[0104] In step S14, the curing agent is calcium aluminate, which accounts for 0.3% of the mass fraction of the aerogel slurry, and the stirring rate is 560 r / min.

[0105] Comparative Examples 1 to 6 are commercially available fiberboards made of the same fiber felt material as those in Examples 1 to 6, and the thickness of Comparative Examples 1 to 6 is the same as that of Examples 1 to 6.

[0106] This invention allows for adjustments to the size and number of layers of the prefabricated spacer mold based on the structure of the packaged item. In practical applications, for items like batteries, the traditional method involves attaching six fiberboard sheets to the six sides of the battery. When using this invention to wrap and protect batteries, the minimum number of sheets required can be as low as two. Figure 5 and Figure 6 As shown, the object is wrapped around its entire surface along the Y-axis. When wrapping along the Y-axis, after using the flexible aerogel fiber felt, a second wrap along either the X or Z axis is performed, allowing for allowance in both the lateral and longitudinal widths to ensure a tight fit between the flexible aerogel fiber felt and the edges of the object. After one wrap, the ends can be sewn to ensure a complete connection. The optimal wrapping method involves wrapping three flexible aerogel fiber felts along the X, Y, and Z axes respectively, and then sewing the ends. This method offers higher mechanical strength and packaging integrity, reducing thermal conductivity loss due to gaps in the seams. Compared to traditional six-sided bonded insulation packaging, embodiments one through six of this invention, compared to fiberboard of the same thickness, show better performance results in terms of thermal conductivity, bonding strength, and tensile properties. This results in better overall thermal conductivity and resistance to external impacts, as shown in Table 1.

[0107]

[0108] Table 1

[0109] This invention uses inorganic silica aerogel as the main material, which is composited with fiber felt. This composite process ensures a tight bond between the components, resulting in better stability during transportation and use, increasing the tensile and compressive strength of the material, and reducing the possibility of particle shedding and powdering. The molding agent and filler aerogel are filled into the fiber felt in an intermittent arrangement. After removing the pre-occupied spaces, gaps remain on the fiber felt, allowing the aerogel fiber felt to be bent and folded. The aerogel filling the fiber felt is the basis for insulation. During use, the gaps left by the pre-occupied spaces allow the fiber felt to be bent or folded, which can be fully wrapped around products requiring heat insulation or thermal insulation. Its excellent thermal conductivity can be fully utilized. The composite strength of the aerogel fiber felt also greatly expands its application range, making it more conducive to mass production and commercialization.

[0110] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0111] The embodiments described above are merely illustrative of implementation methods of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for preparing an aerogel fiber mat, characterized in that: Includes the following steps: A fiber mat is provided, on which a plurality of prefabricated placeholders are placed at intervals; The molding agent is poured into the prefabricated spacer mold to form spaced pre-spacers on the fiber felt; The aerogel slurry is filled into the gap between adjacent pre-occupied spaces, and after full curing, it is dried. Remove the molding agent from the pre-placement and remove the pre-made placeholder mold from the fiber felt to obtain an aerogel fiber felt; the preparation method of the aerogel slurry is as follows: Add the dispersant to water and stir thoroughly to obtain a dispersion. Inorganic silica aerogel particles were added to the dispersion and stirred thoroughly to obtain a primary aerogel slurry. The adhesive is added to the primary aerogel slurry and stirred thoroughly to obtain the secondary aerogel slurry; Add the curing agent to the secondary aerogel slurry and stir thoroughly to obtain the aerogel slurry; The molding agent is one of paraffin wax, asphalt, and rosin; The dispersant is one of sodium oleate, sulfate ester salt, and sulfonate; the adhesive is one of polyvinyl alcohol, silicate, borate, and polyvinylidene fluoride; and the curing agent is one of magnesium oxide and calcium aluminate.

2. The method for preparing aerogel fiber mat according to claim 1, characterized in that: The fiber felt is one of basalt fiber, glass fiber, ceramic fiber, or carbon fiber.

3. The method for preparing aerogel fiber mat according to claim 1, characterized in that: The pre-occupied section is rectangular, the width of the pre-occupied section is 0.1mm~1mm, the thickness of the pre-occupied section is 0.1mm~1mm, and the interval of the pre-occupied sections is 2mm~8mm.

4. The method for preparing aerogel fiber mat according to claim 1, characterized in that: The pre-occupied space can be one or more layers, and the pre-occupied spaces in multiple layers are arranged parallel to each other in the vertical direction.

5. The method for preparing aerogel fiber mat according to claim 1, characterized in that: The filling method of the aerogel slurry includes one of impregnation, spraying, and coating, and the drying treatment includes one of supercritical drying, environmental drying, and freeze drying.

6. The method for preparing aerogel fiber mat according to claim 1, characterized in that: The method of removing the molding agent includes one of the following: high-temperature settling, blowing, and solvent replacement.

7. The method for preparing aerogel fiber mat according to claim 1, characterized in that: The molar ratio of the dispersant to water is (0.02mol~0.1mol):1mol, and the stirring rate of the dispersant added to the water is 800r / min~5000r / min; The inorganic silica aerogel particles account for 10% to 20% of the mass fraction of the primary aerogel slurry, and the inorganic silica aerogel particles are added to the dispersion at a stirring rate of 300 r / min to 500 r / min. The adhesive accounts for 1% to 10% of the mass fraction of the secondary aerogel slurry, and the adhesive is added to the primary aerogel slurry at a stirring rate of 200 r / min to 600 r / min. The curing agent accounts for 0.1% to 1% of the mass fraction of the aerogel slurry, and the curing agent is added to the secondary aerogel slurry at a stirring rate of 500 r / min to 700 r / min.

8. An aerogel fiber felt, characterized in that: It is obtained by the preparation method according to any one of claims 1 to 7.

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