Fireproof thermal insulation composite material and preparation method and application thereof

Abstract

This invention relates to a fire-resistant, heat-insulating, and thermally insulating composite material, its preparation method, and its application. The composite material comprises an outer layer and an inner layer stacked together, connected by weaving and / or quilting. The outer layer includes a first woven layer made of a first continuous refractory fiber, with a bimetallic hydroxide epitaxially grown in situ on the surface of the first continuous refractory fiber. The inner layer includes a second woven layer made of a second continuous refractory fiber, with flexible aerogel disposed on the surface and / or in the cavities of the second woven layer. The interlayer anions of the bimetallic hydroxide include carbonate and / or bicarbonate ions. This invention utilizes continuous refractory fibers, which are beneficial for flame retardancy, fire prevention, and heat insulation. The bimetallic hydroxide in the outer layer can release interlayer water and hydroxyl water at high temperatures, and the interlayer anions can decompose into carbon dioxide, actively cooling and extinguishing open flames. The flexible aerogel in the inner layer is beneficial for heat insulation. The connection method avoids the use of polymer adhesives, resulting in good air permeability.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary field of fire protection technology and composite materials, and relates to a fireproof, heat-insulating and thermally insulating composite material, and more particularly to a fireproof, heat-insulating and thermally insulating composite material, its preparation method and application. Background Technology

[0002] In recent years, fire accidents have occurred frequently and the fire scene environment has become increasingly complex, significantly increasing the risk of injury and death for firefighters during firefighting and rescue operations. Data shows that in the past five years, approximately 144 firefighters in my country have died in rescue operations, and more than 300 firefighters are burned each year, making firefighters the "professional with the highest number of casualties in peacetime."

[0003] Therefore, fire-fighting suits should possess advantages such as high temperature resistance, fire resistance, flame retardancy, heat insulation, good breathability, high comfort, and lightweight. CN117465088A discloses a fire-resistant and flame-retardant multi-layer composite fabric for fire-fighting suits and its preparation method. The fire-resistant and flame-retardant multi-layer composite fabric is made by stitching together a fire-resistant and abrasion-resistant layer, a fire-resistant and heat-insulating breathable layer, a cooling layer, and a comfort layer from the outside to the inside. The fire-resistant and abrasion-resistant layer is made of a blend of polyacrylonitrile pre-oxidized fiber and modified basalt fiber. The fire-resistant and heat-insulating breathable layer is composed of polyacrylonitrile pre-oxidized fiber, ceramic fiber, and a heat-insulating coating. The heat-insulating coating includes modified silica aerogel and polyurethane emulsion. The cooling layer is made of 20-30 parts of hydrogel and 70-80 parts of hydrophilic fiber. The comfort layer is composed of aramid nonwoven fabric. It has excellent flame retardant, temperature resistance, heat insulation, and protective properties, and can be used for short-term work in large fires. CN120269888A discloses a flame-retardant and heat-insulating fabric for fire-fighting clothing and its preparation process. The flame-retardant and heat-insulating fabric includes a flame-retardant outer layer, a heat-insulating core layer, and an antibacterial inner layer. The flame-retardant outer layer is woven from modified polyester fibers; the heat-insulating core layer is a blend of synthetic fibers and aramid fibers; and the antibacterial inner layer is made by soaking cotton fabric in a modified treatment solution. It exhibits good flame-retardant, heat-insulating, and antibacterial properties. CN114592356A discloses a heat-insulating material for fire-fighting clothing and its preparation method. This involves dissolving polyacrylate in acetone, adding aerogel and carbon fiber to obtain a mixed heat-insulating adhesive, and then coating it onto aramid fabric to obtain a heat-insulating aramid base fabric. A composite dry gel is added to anhydrous ethanol to form a suspension, which is then sprayed onto a fabric veil to obtain a heat-insulating fabric veil. Finally, the heat-insulating aramid base fabric and the heat-insulating fabric veil are bonded together using an adhesive (polyurethane adhesive) to obtain the heat-insulating material for fire-fighting clothing. It exhibits good heat insulation performance.

[0004] However, traditional firefighting suits have many technical defects: First, they lack high-temperature resistance. The mainstream aramid fabric can only withstand temperatures below 400℃. Above this temperature, they lose their protective performance and release toxic fumes as the organic matter decomposes. Second, they are bulky. The existing four- or three-layer structure design makes them stuffy and physically demanding, affecting rescue efficiency. Third, there is an imbalance in thermal insulation. The insulation effect decays rapidly in high-temperature environments, while in extremely cold regions (temperature ≤ -10℃), there is a lack of effective insulation, causing firefighters to feel uncomfortable. Fourth, the connection method is unreasonable. Most of them are currently bonded with polymer adhesives, which not only block the pores and reduce breathability, but also easily fail at high temperatures, posing a safety hazard. In addition, some cooling solutions (such as water injection and cold storage agents) have problems such as increased weight and inconvenience of use.

[0005] Therefore, developing a multifunctional fireproof and heat-insulating composite material that integrates high temperature resistance, high safety, balanced thermal insulation, lightweight and breathability, and superior comfort is an urgent problem to be solved in the field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a fire-resistant, heat-insulating, and thermally insulating composite material, its preparation method, and its applications. In this invention, both the first and second woven layers of the fire-resistant, heat-insulating, and thermally insulating composite material are made of continuous refractory fibers, possessing excellent high-temperature resistance and uniform micropores, which are beneficial for flame retardancy, fire prevention, and heat insulation. The outer layer of bimetallic hydroxide can decompose at high temperatures, releasing interlayer water and hydroxyl water. The carbonate and / or bicarbonate ions in the interlayer can simultaneously decompose into carbon dioxide, actively cooling and extinguishing directly contacted open flames. The inner layer of flexible aerogel provides balanced heat insulation and is lightweight and comfortable. The fire-resistant, heat-insulating, and thermally insulating composite material is connected by weaving and / or quilting, ensuring interlayer stability and eliminating the risk of slippage and detachment. It also avoids the use of polymer adhesives, has good air permeability, and does not decompose to produce toxic gases.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a fireproof, heat-insulating, and thermally insulating composite material, comprising an outer layer and an inner layer stacked together, the outer layer and the inner layer being connected by weaving and / or quilting; the outer layer comprising a first woven layer woven from a first continuous refractory fiber, wherein a bimetallic hydroxide is epitaxially grown in situ on the surface of the first continuous refractory fiber; the inner layer comprising a second woven layer woven from a second continuous refractory fiber, wherein a flexible aerogel is disposed on the surface and / or in the cavities of the second woven layer; the interlayer anions of the bimetallic hydroxide comprising carbonate and / or bicarbonate ions.

[0009] In this invention, both the first and second woven layers of the fireproof and heat-insulating composite material are made of continuous refractory fiber, which has good high-temperature resistance and uniform micropores, which is beneficial for flame retardancy, fire prevention, and heat insulation. The outer layer of bimetallic hydroxide can decompose and release interlayer water and hydroxyl water at high temperatures, and the carbonate and / or bicarbonate ions in the interlayer can decompose into carbon dioxide simultaneously, which can actively cool down and extinguish open flames in direct contact. The inner layer of flexible aerogel provides balanced heat insulation and is lightweight and comfortable. The fireproof and heat-insulating composite material is connected by weaving and / or quilting, which can ensure interlayer stability and eliminate the risk of slippage and detachment. At the same time, it can avoid the use of polymer adhesives, has good air permeability, and will not decompose to produce toxic gases.

[0010] Preferably, the first continuous refractory fiber and the second continuous refractory fiber each independently comprise any one or a combination of at least two of high-silica fibers, polycrystalline zirconia fibers, or alumina fibers, and more preferably a combination of high-silica fibers, polycrystalline zirconia fibers, and alumina fibers.

[0011] In this invention, the first and second continuous refractory fibers are selected by combining high-silica fibers, polycrystalline zirconia fibers and alumina fibers. This combination can integrate the high spinning continuity and flexibility of high-silica fibers, the ultra-high temperature stability and thermal insulation performance of polycrystalline zirconia fibers, and the high temperature stability and flexibility of alumina fibers. As a result, the continuous refractory fibers have good high temperature resistance and flexibility, which is beneficial for flame retardancy, fire prevention and thermal insulation, and also provides good comfort.

[0012] Preferably, in the combination of high-silica fibers, polycrystalline zirconia fibers, and alumina fibers, the mass ratio of the high-silica fibers, polycrystalline zirconia fibers, and alumina fibers is (4~6):(3~4):(1~2), for example, it can be 4:3:1, 4:3:2, 4:4:1, 4:4:2, 5:3:1, 5:3:2, 5:4:1, 5:4:2, 6:3:1, 6:3:2, 6:4:1, or 6:4:2, etc.

[0013] In this invention, by controlling the mass ratio of high-silica fibers, polycrystalline zirconia fibers, and alumina fibers to (4~6):(3~4):(1~2), the high-temperature resistance and flexibility of continuous refractory fibers can be further improved. If the content of high-silica fibers is too high, the high-temperature resistance of continuous refractory fibers will decrease; if the content of high-silica fibers is too low, continuous spinning will be difficult, the fiber breakage rate will be high, and it will be difficult to prepare continuous long fibers. If the content of polycrystalline zirconia fibers is too high, the fiber breakage rate will be high and the flexibility will be poor; if the content of polycrystalline zirconia fibers is too low, the high-temperature resistance of continuous refractory fibers will decrease. If the content of alumina fibers is too high, it will lead to a decrease in the proportion of high-silica fibers and polycrystalline zirconia fibers, the overall performance improvement of continuous refractory fibers will be limited, and the raw material cost will also increase; if the content of alumina fibers is too low, it will lead to a poorer interfacial bonding between high-silica fibers and polycrystalline zirconia fibers, easy interfacial debonding, and poor structural stability.

[0014] Preferably, the silicon dioxide content of the high-silica fiber is 95.5wt% to 98.5wt%, for example, it can be 95.5wt%, 96wt%, 96.5wt%, 97wt%, 97.5wt%, 98wt%, or 98.5wt%.

[0015] Preferably, the alumina fibers are mullite phase and / or γ-Al2O3 microcrystalline state.

[0016] Preferably, when the alumina fiber is a mullite phase, the mass ratio of Al2O3 to SiO2 is (70~73):(30~27), ​​for example, it can be 70:30, 71:29, 72:28 or 73:27, etc.

[0017] Preferably, when the alumina fiber is in the γ-Al2O3 microcrystalline state, the mass percentage of Al2O3 in the alumina fiber is ≥99wt%, for example, it can be 99wt%, 99.1wt%, 99.2wt%, 99.3wt%, 99.4wt%, 99.5wt%, 99.6wt%, 99.7wt%, 99.8wt%, or 99.9wt%, etc.

[0018] Preferably, the diameters of the first continuous refractory fiber and the second continuous refractory fiber are independently 5μm to 10μm, for example, they can be 5μm, 6μm, 7μm, 8μm, 9μm or 10μm, etc.

[0019] In this invention, by adjusting the diameters of the first and second continuous refractory fibers to 5μm~10μm, the resulting woven layer has uniform micropores, which can balance heat insulation and air permeability. Simultaneously, it provides sufficient stress dispersion and thermal expansion buffer space at high temperatures, making it less prone to deformation and brittleness, and exhibiting strong high-temperature resistance. If the continuous refractory fibers are too fine, they are prone to sintering and agglomeration at high temperatures and melting and sticking at low temperatures, resulting in decreased high-temperature resistance and potential failure of the heat insulation structure. Conversely, if the continuous refractory fibers are too coarse, stress concentration at high temperatures leads to deformation and brittleness, and the resulting woven layer has excessively large pores, reducing its heat insulation performance.

[0020] Preferably, the bimetallic hydroxide includes any one or a combination of at least two of Mg / Al bimetallic hydroxide, Ca / Al bimetallic hydroxide, Ni / Al bimetallic hydroxide, or Ni / Fe bimetallic hydroxide. Typical but non-limiting combinations include combinations of Mg / Al bimetallic hydroxide and Ca / Al bimetallic hydroxide, combinations of Ni / Al bimetallic hydroxide and Ni / Fe bimetallic hydroxide, combinations of Mg / Al bimetallic hydroxide, Ca / Al bimetallic hydroxide and Ni / Al bimetallic hydroxide, combinations of Ca / Al bimetallic hydroxide, Ni / Al bimetallic hydroxide and Ni / Fe bimetallic hydroxide, and combinations of Mg / Al bimetallic hydroxide, Ca / Al bimetallic hydroxide, Ni / Al bimetallic hydroxide and Ni / Fe bimetallic hydroxide.

[0021] Preferably, the loading of the bimetallic hydroxide on the surface of the first continuous refractory fiber is 5 g / m². 2 ~20g / m 2 For example, it could be 5g / m 2 8g / m 2 10 / m 2 12g / m 2 15g / m 2 18g / m 2 Or 20g / m 2 wait.

[0022] In this invention, the loading amount of bimetallic hydroxide on the surface of the first continuous refractory fiber is adjusted to 5 g / m. 2 ~20g / m 2This can further improve the high-temperature resistance and safety performance of the outer layer. If the loading of bimetallic hydroxide is too low, there will be too little interlayer water and hydroxyl water that can be released at high temperatures, as well as too little carbon dioxide from the decomposition of interlayer carbonate and / or bicarbonate ions. The cooling effect will be weak, making it difficult to extinguish open flames in direct contact. At the same time, there will be fewer binding sites with the continuous refractory fibers, which may cause them to fall off at high temperatures. If the loading of bimetallic hydroxide is too high, it will block the micropore channels of the first braided layer, destroy its thermal insulation structure, and reduce the thermal insulation effect.

[0023] Preferably, the flexible aerogel is a silicon-based aerogel.

[0024] Preferably, the silicon source of the silicon-based aerogel includes any one or a combination of at least two of tetraethyl orthosilicate, methyltrimethoxysilane, dimethyldimethoxysilane, or polyethoxysiloxane. Typical but non-limiting combinations include combinations of tetraethyl orthosilicate and methyltrimethoxysilane, combinations of dimethyldimethoxysilane and polyethoxysiloxane, combinations of tetraethyl orthosilicate, methyltrimethoxysilane, and dimethyldimethoxysilane, combinations of methyltrimethoxysilane, dimethyldimethoxysilane, and polyethoxysiloxane, and combinations of tetraethyl orthosilicate, methyltrimethoxysilane, dimethyldimethoxysilane, and polyethoxysiloxane. Preferably, it is a combination of tetraethyl orthosilicate and methyltrimethoxysilane.

[0025] Preferably, in the combination of tetraethyl orthosilicate and methyltrimethoxysilane, the volume ratio of tetraethyl orthosilicate to methyltrimethoxysilane is 1:(0.3~0.5), for example, it can be 1:0.3, 1:0.35, 1:0.4, 1:0.45 or 1:0.5, etc.

[0026] In this invention, by selecting a combination of tetraethyl orthosilicate and methyltrimethoxysilane and controlling their volume ratio to 1:(0.3~0.5), the thermal insulation and heat preservation performance of the inner layer can be further improved. If the volume ratio of tetraethyl orthosilicate to methyltrimethoxysilane is too small, the mechanical strength of the silicon-oxygen skeleton of the flexible aerogel is too low, and it is prone to deformation and collapse under extreme conditions, failing to maintain a continuous porous structure, thus affecting the thermal insulation and heat preservation performance. If the volume ratio of tetraethyl orthosilicate to methyltrimethoxysilane is too large, the silicon-oxygen skeleton of the flexible aerogel is too dense, the thermal conductivity increases at high temperatures, the thermal insulation effect decreases, and the air permeability is poor, making it less lightweight.

[0027] Preferably, the mass ratio of the flexible aerogel to the second woven layer is 1:(3~8), for example, it can be 1:3, 1:4, 1:5, 1:6, 1:7 or 1:8, etc.

[0028] In this invention, by adjusting the mass ratio of flexible aerogel to the second braided layer to 1:(3~8), the thermal insulation and heat preservation performance of the inner layer can be further improved. If the mass ratio of flexible aerogel to the second braided layer is too small, the thermal insulation and heat preservation effect of the flexible aerogel will be insignificant, thus affecting the thermal insulation and heat preservation performance of the inner layer; if the mass ratio of flexible aerogel to the second braided layer is too large, it will block the micropore channels of the second braided layer, destroy its thermal insulation structure, and reduce the thermal insulation and heat preservation effect.

[0029] Preferably, the first braided layer is a planar structure, and the second braided layer is a planar structure and / or a hollow structure.

[0030] Preferably, the weaving method includes any one or a combination of at least two of plain weave, twill weave, or satin weave. Typical but non-limiting combinations include a combination of plain weave and twill weave, a combination of twill weave and satin weave, a combination of plain weave and satin weave, and a combination of plain weave, twill weave, and satin weave.

[0031] Preferably, the quilting material includes the continuous refractory fiber.

[0032] Preferably, the spacing of the quilting is 1cm to 3cm, for example, it can be 1cm, 1.5cm, 2cm, 2.5cm or 3cm, etc.

[0033] Preferably, the stitch density of the quilting is 10 stitches / cm to 15 stitches / cm, for example, it can be 10 stitches / cm, 11 stitches / cm, 12 stitches / cm, 13 stitches / cm, 14 stitches / cm or 15 stitches / cm, etc.

[0034] Preferably, the second woven layer and the flexible aerogel are connected or fixed by quilting.

[0035] It should be noted that when the second braided layer is a planar structure, flexible aerogel is provided on the surface of the second braided layer, and the second braided layer and the flexible aerogel are fixed by quilting; when the second braided layer is a hollow structure, flexible aerogel is provided in the cavity of the second braided layer, and the second braided layer and the flexible aerogel are connected by quilting.

[0036] In this invention, the second braided layer and the flexible aerogel can be well fixed by using quilting to connect or fix them.

[0037] In a second aspect, the present invention provides a method for preparing a fire-resistant, heat-insulating, and thermally insulating composite material as described in the first aspect, comprising the following steps:

[0038] (1) Preparation of outer layer: The first continuous refractory fiber is woven to obtain the first woven layer; the first woven layer is placed in a bimetallic salt solution, and after vacuuming, an alkaline solution is added to carry out a co-precipitation reaction or a hydrothermal reaction, and a bimetallic hydroxide is epitaxially grown in situ on the surface of the first continuous refractory fiber to obtain the outer layer.

[0039] (2) Inner layer preparation: the second continuous refractory fiber is woven to obtain the second woven layer; flexible aerogel is coated on the surface of the second woven layer, and / or the cavity of the second woven layer is filled with flexible aerogel, and aged and dried to obtain the inner layer.

[0040] (3) Interlayer bonding: The outer layer and the inner layer are connected by weaving and / or quilting to obtain the fireproof and heat-insulating composite material.

[0041] Preferably, the bimetallic salt solution comprises any one or a combination of at least two of nitrates, sulfates, or chlorides. Typical but non-limiting combinations include combinations of nitrates and sulfates, combinations of sulfates and chlorides, combinations of nitrates and chlorides, and combinations of nitrates, sulfates, and chlorides.

[0042] Preferably, the metal ion pair in the bimetallic salt solution includes Mg. 2+ / Al 3+ Ca 2+ / Al 3+ Ni 2+ / Al 3+ or Ni 2+ / Fe 3+ Any one or at least two of the following, typical but non-limiting combinations include Mg 2+ / Al 3+ and Ca 2+ / Al 3 + The combination of Ni 2+ / Al 3+ and Ni 2+ / Fe 3+ Combination of Mg 2+ / Al 3+ Ca 2+ / Al 3+ and Ni 2+ / Al 3+ The combination, Ca 2+ / Al 3+ Ni 2 + / Al 3+ and Ni 2+ / Fe 3+ Combination of Mg 2+ / Al3+ Ca 2+ / Al 3+ Ni 2+ / Al 3+ and Ni 2+ / Fe 3+ The combination of .

[0043] Preferably, the total concentration of the metal ion pairs in the bimetallic salt solution is 0.1 mol / L to 0.5 mol / L, for example, it can be 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L or 0.5 mol / L, etc.

[0044] Preferably, in the metal ion pair, the molar ratio of the two metal ions is (1~2):(1~2), for example, it can be 1:1, 1:1.5, 1:2, 2:1 or 2:1.5, etc.

[0045] Preferably, the vacuuming to an absolute pressure ≤133Pa can be, for example, 50Pa, 60Pa, 80Pa, 100Pa, 120Pa, 130Pa or 133Pa.

[0046] Preferably, the alkaline solution comprises any one or a combination of at least two of sodium carbonate, sodium bicarbonate, ammonia, or urea. Typical but non-limiting combinations include combinations of sodium carbonate and sodium bicarbonate, combinations of ammonia and urea, combinations of sodium carbonate, sodium bicarbonate, and ammonia, combinations of sodium bicarbonate, ammonia, and urea, and combinations of sodium carbonate, sodium bicarbonate, ammonia, and urea.

[0047] Preferably, the concentration of the alkaline solution is 0.1 mol / L to 1 mol / L, for example, it can be 0.1 mol / L, 0.2 mol / L, 0.5 mol / L, 0.6 mol / L, 0.8 mol / L or 1 mol / L, etc.

[0048] Preferably, the method for preparing the flexible aerogel includes the following steps:

[0049] A silicon source and an organic solvent are mixed to obtain a silicon source solution; acid is added to the silicon source solution to adjust the pH once and a hydrolysis reaction is carried out; then alkali is added to adjust the pH a second time, and the mixture is stirred to obtain the flexible aerogel.

[0050] Preferably, the organic solvent includes methanol.

[0051] Preferably, the acid includes any one or a combination of at least two of hydrochloric acid, sulfuric acid, or nitric acid. Typical but non-limiting combinations include combinations of hydrochloric acid and sulfuric acid, combinations of sulfuric acid and nitric acid, combinations of hydrochloric acid and nitric acid, and combinations of hydrochloric acid, sulfuric acid, and nitric acid.

[0052] Preferably, the concentration of the acid is 0.01 mol / L to 0.05 mol / L, for example, it can be 0.01 mol / L, 0.02 mol / L, 0.03 mol / L, 0.04 mol / L or 0.05 mol / L, etc.

[0053] Preferably, the pH adjustment is to adjust the pH to 2-4, for example, 2, 2.5, 3, 3.5 or 4.

[0054] In this invention, by adjusting the pH to 2-4, the silicon source can be fully hydrolyzed to form a uniform sol. When the pH is below 2, the hydrolysis rate is too fast, the gel pore size distribution is uneven, and the specific surface area decreases.

[0055] Preferably, the hydrolysis reaction takes 1 to 3 hours, for example, 1 hour, 1.5 hours, 2 hours, 2.5 hours, or 3 hours.

[0056] Preferably, the alkali includes ammonia.

[0057] Preferably, the concentration of the ammonia water is 1 mol / L to 2 mol / L, for example, it can be 1 mol / L, 1.2 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.8 mol / L or 2 mol / L, etc.

[0058] Preferably, the secondary pH adjustment is to adjust the pH to 9~10, for example, it can be 9, 9.2, 9.4, 9.6, 9.8 or 10, etc.

[0059] Preferably, the stirring speed is 300 rpm to 500 rpm, for example, it can be 300 rpm, 350 rpm, 400 rpm, 450 rpm or 500 rpm.

[0060] Preferably, the stirring time is 3 min to 15 min, for example, it can be 3 min, 5 min, 8 min, 10 min, 12 min or 15 min.

[0061] Preferably, the silicon source solution further includes an additive, which includes any one or a combination of at least two of sodium bicarbonate, nano-aluminum sol, or surfactant. Typical but non-limiting combinations include a combination of sodium bicarbonate and nano-aluminum sol, a combination of nano-aluminum sol and surfactant, a combination of sodium bicarbonate and surfactant, or a combination of sodium bicarbonate, nano-aluminum sol, and surfactant.

[0062] Preferably, the additive in the silicon source solution has a mass percentage of 1wt% to 3wt%, for example, it can be 1wt%, 1.5wt%, 2wt%, 2.5wt%, or 3wt%.

[0063] Preferably, before placing the first braided layer in the bimetallic salt solution, the first braided layer is further subjected to ultrasonic treatment and drying.

[0064] Preferably, a flexible aerogel is coated on the surface of the second woven layer, and / or, before the flexible aerogel is filled into the cavity of the second woven layer, the second woven layer is further subjected to ultrasonic treatment and drying.

[0065] Preferably, the solution used for ultrasonic treatment includes ethanol and / or acetone.

[0066] Preferably, the ultrasonic treatment time is 15 min to 30 min, for example, it can be 15 min, 18 min, 20 min, 22 min, 25 min, 28 min or 30 min.

[0067] Preferably, the drying temperature is 60℃~100℃, for example, it can be 60℃, 70℃, 80℃, 90℃ or 100℃.

[0068] Preferably, the drying time is 1 hour to 5 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours or 5 hours.

[0069] Preferably, the temperature of the coprecipitation reaction is 10℃~80℃, for example, it can be 10℃, 20℃, 30℃, 40℃, 50℃, 60℃, 70℃ or 80℃, etc.

[0070] Preferably, the coprecipitation reaction time is 0.5h to 24h, for example, it can be 0.5h, 1h, 2h, 5h, 8h, 10h, 12h, 15h, 18h, 20h, 22h or 24h.

[0071] Preferably, the temperature of the hydrothermal reaction is 70℃~250℃, for example, it can be 70℃, 100℃, 120℃, 150℃, 180℃, 200℃, 220℃ or 250℃.

[0072] Preferably, the hydrothermal reaction time is 5h to 36h, for example, it can be 5h, 10h, 15h, 20h, 25h, 30h or 36h.

[0073] Preferably, the aging treatment temperature is 30℃~60℃, for example, it can be 30℃, 35℃, 40℃, 45℃, 50℃, 55℃ or 60℃, etc.

[0074] Preferably, the aging treatment time is 12h to 24h, for example, it can be 12h, 14h, 16h, 18h, 20h, 22h or 24h.

[0075] Preferably, the drying process includes supercritical carbon dioxide drying.

[0076] Thirdly, the present invention provides an application of the fireproof, heat-insulating and thermally insulating composite material as described in the first aspect, wherein the fireproof, heat-insulating and thermally insulating composite material is used as the outer fabric of fire-fighting suits, industrial high-temperature operation protective equipment, or protective equipment in extremely cold regions.

[0077] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0078] Compared with the prior art, the present invention has the following beneficial effects:

[0079] (1) In this invention, the first and second woven layers of the fireproof and heat-insulating composite material are both made of continuous refractory fiber, which has good high temperature resistance and uniform micropores, which is beneficial for flame retardancy, fire prevention and heat insulation; the bimetallic hydroxide of the outer layer can decompose and release interlayer water and hydroxyl water at high temperature, and the carbonate and / or bicarbonate of the interlayer can be decomposed into carbon dioxide simultaneously, which can actively cool down and extinguish open flames in direct contact; the flexible aerogel of the inner layer provides balanced heat insulation and is lightweight and comfortable; the fireproof and heat-insulating composite material is connected by weaving and / or quilting, which can ensure interlayer stability and eliminate the risk of slippage and falling off, while avoiding the use of polymer adhesives, having good air permeability and not decomposing to produce toxic gases.

[0080] (2) The fireproof, heat-insulating, and thermally insulating composite material provided by the present invention has a maximum temperature resistance ≥1050℃, thermal conductivity ≤0.03W / (m·K), tensile strength ≥15MPa, porosity ≥85%, and moisture permeability ≥450g / (m·K). 2 • 24h) and -30℃ for 2h, with an inner temperature ≥10℃. Attached Figure Description

[0081] Figures 1-2 This is a schematic diagram of the cross-sectional structure of the fireproof, heat-insulating, and thermally insulating composite material provided by the present invention.

[0082] Wherein, 1 is the outer layer and 2 is the inner layer.

[0083] Figure 3 This is a SEM image of the first braided layer of the outer layer in Embodiment 1 of the present invention.

[0084] Figure 4 This is a SEM image of the in-situ epitaxial growth of the outer Mg / Al bimetallic hydroxide on the surface of the first continuous refractory fiber in Embodiment 1 of the present invention.

[0085] Figure 5This is a SEM image of the flexible aerogel in the inner layer of Embodiment 1 of the present invention. Detailed Implementation

[0086] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0087] The "range" disclosed in this invention can be defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the specific range. This type of range definition can include or exclude endpoints; any endpoint can be independently included or excluded, and they can be arbitrarily combined, meaning any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for specific parameters, it is understood that ranges of 60~110 and 80~120 are also expected. Furthermore, if minimum range values ​​1 and 2 are listed, and maximum range values ​​3, 4, and 5 are also listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this invention, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0" and "5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is described as an integer ≥2, it is equivalent to listing integers such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For instance, when a parameter is described as an integer selected from "2~10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0088] In this invention, "a combination of at least two" refers to a quantity greater than or equal to two, unless otherwise specified. For example, "any combination of one or at least two" means one or more or more items. It can be understood that when referring to "a combination of at least two," it refers to any suitable combination of multiple items, that is, a combination of "at least two" items carried out in a manner that does not conflict with and enables the implementation of this invention.

[0089] Unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form new technical solutions.

[0090] The term "embodiment" as used in this invention means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0091] Those skilled in the art will understand that the order in which the steps are written in the methods of the various embodiments does not imply a strict execution order. The detailed execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of the present invention may be performed sequentially or randomly, but are preferably performed sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), meaning that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0092] In this invention, open-ended technical features or solutions described using terms such as "comprising" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, A includes a1, a2, and a3. Unless otherwise specified, it may also include other members or exclude additional members. This can be considered as providing both technical features or solutions where "A is composed of a1, a2, and a3" or "A is selected from a1, a2, and a3," and technical features or solutions where "A includes not only a1, a2, and a3, but also other members."

[0093] In this invention, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" represents a group consisting of A, B, and "a combination of A and B". "Containing A and / or B" can mean "containing A, containing B, and containing A and B", or "containing A, containing B, or containing A and B", and can be appropriately understood according to the context.

[0094] In this invention, the terms "first aspect," "second aspect," "third aspect," "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," "fourth," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on the quantity.

[0095] Example 1

[0096] This embodiment provides a fireproof, heat-insulating, and thermally insulating composite material, comprising an outer layer and an inner layer stacked together and connected by quilting. The outer layer is a first woven layer woven from a first continuous refractory fiber, on the surface of which Mg / Al bimetallic hydroxide is epitaxially grown in situ, with carbonate and bicarbonate anions forming the interlayer anions. The inner layer is a second woven layer woven from a second continuous refractory fiber, with flexible aerogel disposed in the cavities of the second woven layer. The loading of Mg / Al bimetallic hydroxide on the surface of the first woven layer is 12 g / m². 2 The flexible aerogel is a silicon-based aerogel, and its mass ratio to the second braided layer is 1:5.

[0097] The method for preparing the fireproof, heat-insulating, and thermally insulating composite material provided in this embodiment includes the following steps:

[0098] (1) Outer layer preparation: Continuous refractory fibers with a diameter of 8 μm and a mass ratio of 4:3:2, consisting of high-silica fibers, polycrystalline zirconia fibers, and alumina fibers, were selected and plain-woven to obtain the first woven layer (planar structure, thickness 0.8 mm). After ultrasonic treatment with ethanol for 20 min, the layer was dried at 80 °C for 3 h. The first woven layer was then placed in a 0.3 mol / L bimetallic salt solution of magnesium nitrate / aluminum nitrate (Mg... 2+ With Al 3+ The molar ratio of sodium carbonate to sodium bicarbonate is 2:1. After vacuuming for 30 minutes, a mixed alkaline solution of 0.5 mol / L sodium carbonate / sodium bicarbonate is added, and the pH is maintained at 9. The co-precipitation reaction is carried out at 60℃ for 6 hours. After washing until neutral, the mixture is dried at 100℃ for 4 hours to obtain the outer layer.

[0099] (2) Inner layer preparation: Continuous refractory fibers with a diameter of 8 μm, a mass ratio of 4:3:2, high silica fiber, polycrystalline zirconia fiber and alumina fiber were selected and plain woven to obtain the second woven layer (hollow structure, thickness of 1.2 mm). After ultrasonic treatment with ethanol for 20 min, it was dried at 80 °C for 3 h. Tetraethyl orthosilicate and methyltrimethoxysilane with a volume ratio of 1:0.4 were added to methanol, 0.03 mol / L hydrochloric acid was added to adjust the pH to 3, and the hydrolysis reaction was carried out for 2 h. Then 1 mol / L ammonia was added to adjust the pH to 9.5, and the mixture was stirred at 400 rpm for 5 min to obtain flexible aerogel. The cavity of the second woven layer was filled with flexible aerogel and fixed by quilting. It was aged at 40 °C for 18 h and dried by supercritical carbon dioxide to obtain the inner layer.

[0100] (3) Interlayer bonding: The outer layer and the inner layer are connected by quilting. The quilting material is continuous refractory fiber with a spacing of 2cm and a stitch density of 12 stitches / cm to obtain a fireproof, heat-insulating and heat-preserving composite material.

[0101] Figure 3 This is an SEM image of the first woven layer of the outer layer in this embodiment. It can be seen that the weaving method is plain weave, and the woven layer formed has uniform micropores, which is beneficial to balance heat insulation and breathability.

[0102] Figure 4 This is a SEM image of the in-situ epitaxial growth of the outer layer of Mg / Al bimetallic hydroxide on the surface of the first continuous refractory fiber in this embodiment. It can be seen that the preparation method provided in this embodiment yields a Mg / Al bimetallic hydroxide with a lamellar structure, which is uniformly epitaxially grown in situ on the surface of the first continuous refractory fiber. This is because: in an alkaline system, the positively charged Mg... 2+ Al 3+ It will adsorb onto the surface of the first continuous refractory fiber, which carries a negative charge, and react with OH. - The reaction generates Mg / Al bimetallic hydroxide. Since oxygen atoms are shared between the AlO6 octahedra of the Mg / Al bimetallic hydroxide and the (Si-Al)O4 tetrahedra of the refractory fiber, and lattice matching is achieved through Al-OM bonds (M is Si or Al), the Mg / Al bimetallic hydroxide grows in situ epitaxially along a direction at a certain angle to the surface of the first continuous refractory fiber, and has strong bonding force, thus avoiding detachment after ultrasonic treatment.

[0103] Figure 5This is an SEM image of the flexible aerogel in the inner layer of this embodiment. The flexible aerogel is a silicon-based flexible aerogel. It is formed by using a silicon source as a precursor and forming a three-dimensional nano-network through the sol-gel method. Then, it is dried by supercritical carbon dioxide to retain its porous structure. At the same time, flexible segments are introduced to achieve toughness, so that it has the characteristics of being ultra-lightweight, ultra-low thermal conductivity, high flexibility and high temperature resistance. It can be bent and folded and is not easy to break, which significantly improves its thermal insulation performance and mechanical properties.

[0104] Example 2

[0105] This embodiment provides a fireproof, heat-insulating, and thermally insulating composite material, comprising an outer layer and an inner layer stacked together and connected by weaving. The outer layer is a first woven layer woven from a first continuous refractory fiber, with Ca / Al bimetallic hydroxide epitaxially grown in situ on the surface of the first continuous refractory fiber, the interlayer anion of which is carbonate. The inner layer is a second woven layer woven from a second continuous refractory fiber, with flexible aerogel disposed in the cavities of the second woven layer. The loading of Ca / Al bimetallic hydroxide on the surface of the first woven layer is 5 g / m². 2 The flexible aerogel is a silicon-based aerogel, and its mass ratio to the second braided layer is 1:8.

[0106] The method for preparing the fireproof, heat-insulating, and thermally insulating composite material provided in this embodiment includes the following steps:

[0107] (1) Outer layer preparation: Continuous refractory fibers with a diameter of 5 μm and a mass ratio of 5:4:1, consisting of high-silica fibers, polycrystalline zirconia fibers, and alumina fibers, were selected and twill-woven to obtain the first woven layer (planar structure, thickness 0.5 mm). After ultrasonic treatment with ethanol for 15 min, the layer was dried at 60 °C for 5 h. The first woven layer was then placed in a 0.5 mol / L bimetallic salt solution of calcium nitrate / aluminum nitrate (Ca... 2+ With Al 3+ The molar ratio of sodium carbonate to ammonia is 1:1. After vacuuming for 30 minutes, a mixed alkaline solution of 0.1 mol / L sodium carbonate / ammonia is added, and the pH is maintained at 9. The co-precipitation reaction is carried out at 80℃ for 4 hours. After washing until neutral, the mixture is dried at 100℃ for 4 hours to obtain the outer layer.

[0108] (2) Inner layer preparation: Continuous refractory fibers with a diameter of 5 μm, a mass ratio of 5:4:1, high silica fiber, polycrystalline zirconia fiber and alumina fiber were selected and twill woven to obtain the second woven layer (hollow structure, thickness of 0.8 mm). After ultrasonic treatment with ethanol for 15 min, it was dried at 60 °C for 5 h. Tetraethyl orthosilicate and methyltrimethoxysilane with a volume ratio of 1:0.3 were added to methanol, 0.03 mol / L hydrochloric acid was added to adjust the pH to 2, and the hydrolysis reaction was carried out for 1 h. Then 1.5 mol / L ammonia was added to adjust the pH to 9, and the mixture was stirred at 300 rpm for 15 min to obtain flexible aerogel. The cavity of the second woven layer was filled with flexible aerogel and fixed by quilting. It was aged at 30 °C for 24 h and dried by supercritical carbon dioxide to obtain the inner layer.

[0109] (3) Interlayer bonding: The outer layer and the inner layer are connected by weaving to obtain a fireproof, heat-insulating and heat-preserving composite material.

[0110] Example 3

[0111] This embodiment provides a fireproof, heat-insulating, and thermally insulating composite material, comprising an outer layer and an inner layer stacked together and connected by quilting. The outer layer is a first woven layer woven from a first continuous refractory fiber, on the surface of which Mg / Al bimetallic hydroxide is epitaxially grown in situ, with bicarbonate ions as interlayer anions. The inner layer is a second woven layer woven from a second continuous refractory fiber, with flexible aerogel disposed on its surface. The loading of Mg / Al bimetallic hydroxide on the surface of the first woven layer is 20 g / m². 2 The flexible aerogel is a silicon-based aerogel, and its mass ratio to the second braided layer is 1:3.

[0112] The method for preparing the fireproof, heat-insulating, and thermally insulating composite material provided in this embodiment includes the following steps:

[0113] (1) Outer layer preparation: Continuous refractory fibers with a diameter of 10 μm and a mass ratio of 3:2:1, consisting of high-silica fibers, polycrystalline zirconia fibers, and alumina fibers, were selected and twill-woven to obtain the first woven layer (planar structure, thickness 1 mm). After ultrasonic treatment with acetone for 30 min, the layer was dried at 100 °C for 1 h. The first woven layer was then placed in a 0.3 mol / L bimetallic salt solution of magnesium nitrate / aluminum nitrate (Mg... 2+ With Al 3+ The molar ratio of sodium bicarbonate to urea is 1:2. After vacuuming for 30 minutes, a mixed alkaline solution of 0.1 mol / L sodium bicarbonate / urea is added. The pH is maintained at 9, and the reaction is carried out hydrothermally at 50°C for 12 hours. After washing until neutral, the mixture is dried at 100°C for 4 hours to obtain the outer layer.

[0114] (2) Inner layer preparation: Continuous refractory fibers with a diameter of 10 μm and a mass ratio of 3:2:1, including high silica fibers, polycrystalline zirconia fibers and alumina fibers, were selected and twill woven to obtain the second woven layer (planar structure, thickness of 1 mm). After ultrasonic treatment with acetone for 30 min, the layer was dried at 100 °C for 1 h. Tetraethyl orthosilicate and methyltrimethoxysilane with a volume ratio of 1:0.5 were added to methanol, and 0.03 mol / L hydrochloric acid was added to adjust the pH to 4. The hydrolysis reaction was carried out for 3 h, and then 2 mol / L ammonia was added to adjust the pH to 10. The mixture was stirred at 500 rpm for 3 min to obtain a flexible aerogel. The flexible aerogel was coated on the surface of the second woven layer and connected by quilting. The layer was aged at 60 °C for 12 h and then dried by supercritical carbon dioxide to obtain the inner layer.

[0115] (3) Interlayer bonding: The outer layer and the inner layer are connected by quilting. The quilting material is continuous refractory fiber with a spacing of 1cm and a stitch density of 15 stitches / cm to obtain a fireproof, heat-insulating and heat-preserving composite material.

[0116] Example 4

[0117] This embodiment provides a fireproof, heat-insulating and heat-preserving composite material. Except for the continuous refractory fibers in steps (1) and (2), which are high-silica fibers and polycrystalline zirconia fibers with a mass ratio of 4:3, all other components are the same as in embodiment 1.

[0118] Example 5

[0119] This embodiment provides a fireproof, heat-insulating and heat-preserving composite material. Except for the continuous refractory fibers in steps (1) and (2), which are high-silica fibers and alumina fibers with a mass ratio of 2:1, all other aspects are the same as in embodiment 1.

[0120] Example 6

[0121] This embodiment provides a fireproof, heat-insulating and thermal-preserving composite material. Except for the continuous refractory fibers in steps (1) and (2), which are polycrystalline zirconia fibers and alumina fibers with a mass ratio of 3:2, all other aspects are the same as in embodiment 1.

[0122] Example 7

[0123] This embodiment provides a fireproof, heat-insulating and heat-preserving composite material. Except for the continuous refractory fibers in steps (1) and (2), which are high-silica fibers, polycrystalline zirconia fibers and alumina fibers with a mass ratio of 7:3:2, all other components are the same as in embodiment 1.

[0124] Example 8

[0125] This embodiment provides a fireproof, heat-insulating and heat-preserving composite material. Except for the continuous refractory fibers in steps (1) and (2), which are high-silica fibers, polycrystalline zirconia fibers and alumina fibers with a mass ratio of 3:3:2, all other components are the same as in embodiment 1.

[0126] Example 9

[0127] This embodiment provides a fireproof, heat-insulating and heat-preserving composite material. Except for the continuous refractory fibers in steps (1) and (2), which are high-silica fibers, polycrystalline zirconia fibers and alumina fibers with a mass ratio of 4:1:2, all other components are the same as in embodiment 1.

[0128] Example 10

[0129] This embodiment provides a fireproof, heat-insulating and heat-preserving composite material. Except for the continuous refractory fibers in steps (1) and (2), which are high-silica fibers, polycrystalline zirconia fibers and alumina fibers with a mass ratio of 4:5:2, all other components are the same as in embodiment 1.

[0130] Example 11

[0131] This embodiment provides a fireproof, heat-insulating and thermal-preserving composite material. Except for the diameter of the continuous fire-resistant fiber in steps (1) and (2) being 3 μm, everything else is the same as in embodiment 1.

[0132] Example 12

[0133] This embodiment provides a fireproof, heat-insulating and thermal-preserving composite material. Except for the diameter of the continuous fire-resistant fiber in steps (1) and (2) being 12 μm, everything else is the same as in embodiment 1.

[0134] Example 13

[0135] This embodiment provides a fireproof, heat-insulating, and thermally insulating composite material, except that in step (1), the loading amount of Mg / Al bimetallic hydroxide on the surface of the first continuous refractory fiber is 3 g / m. 2 Except for the above, everything else is the same as in Example 1.

[0136] Example 14

[0137] This embodiment provides a fireproof, heat-insulating, and thermally insulating composite material, except that in step (1), the loading amount of Mg / Al bimetallic hydroxide on the surface of the first continuous refractory fiber is 25 g / m. 2 Except for the above, everything else is the same as in Example 1.

[0138] Example 15

[0139] This embodiment provides a fireproof, heat-insulating and thermal-preserving composite material. Except for the mass ratio of flexible aerogel to the second woven layer in step (2) being 1:1, everything else is the same as in embodiment 1.

[0140] Example 16

[0141] This embodiment provides a fireproof, heat-insulating and thermal-preserving composite material. Except for the mass ratio of flexible aerogel to the second woven layer in step (2) being 1:10, everything else is the same as in embodiment 1.

[0142] Example 17

[0143] This embodiment provides a fireproof, heat-insulating and thermal-preserving composite material. Except for the volume ratio of tetraethyl orthosilicate and methyltrimethoxysilane in step (2) being 1:0.2, everything else is the same as in Example 1.

[0144] Example 18

[0145] This embodiment provides a fireproof, heat-insulating and thermal-preserving composite material. Except for the volume ratio of tetraethyl orthosilicate and methyltrimethoxysilane in step (2) being 1:0.6, everything else is the same as in Example 1.

[0146] Comparative Example 1

[0147] This comparative example uses the fire-resistant and flame-retardant multilayer composite fabric for fire-fighting clothing disclosed in CN117465088A.

[0148] Comparative Example 2

[0149] This comparative example uses the flame-retardant and heat-insulating fabric for fire-fighting clothing disclosed in CN120269888A.

[0150] Comparative Example 3

[0151] This comparative example provides a fireproof, heat-insulating, and thermally insulating composite material. Except for the absence of in-situ epitaxial growth of bimetallic hydroxide on the surface of the first continuous fire-resistant fiber of the first braided layer of the outermost layer, everything else is the same as in Example 1.

[0152] Comparative Example 4

[0153] This comparative example provides a fireproof, heat-insulating, and thermally insulating composite material, which is the same as Example 1 except that the cavity of the second woven layer in the inner layer does not contain flexible aerogel.

[0154] Figure 1 This is a schematic diagram of the cross-sectional structure of the fireproof, heat-insulating and thermal-preserving composite material provided by the present invention. The outer layer includes a first braided layer woven from a first continuous refractory fiber, on which a bimetallic hydroxide is epitaxially grown in situ on the surface of the first continuous refractory fiber. The inner layer includes a second braided layer woven from a second continuous refractory fiber, and the cavity of the second braided layer is provided with flexible aerogel.

[0155] Figure 2This is a schematic diagram of the cross-sectional structure of the fireproof, heat-insulating and thermal-preserving composite material provided by the present invention. The outer layer includes a first braided layer woven from a first continuous refractory fiber, on which a bimetallic hydroxide is epitaxially grown in situ on the surface of the first continuous refractory fiber. The inner layer includes a second braided layer woven from a second continuous refractory fiber, on which a flexible aerogel is disposed.

[0156] The fireproof, heat-insulating, and thermally insulating composite materials / firefighting suit fabrics provided in Examples 1-18 and Comparative Examples 1-4 were tested respectively. The samples were placed in high-temperature chambers at different temperatures for high-temperature thermal stability testing. After 24 hours of constant temperature, the appearance (cracking, powdering, shrinkage) was observed, and the maximum temperature resistance was tested. The thermal conductivity was tested using the protective hot plate method according to GB / T10294-2008. The tensile strength of the fabric was tested according to GB / T3923.1-2013. The porosity was tested using the mercury porosimetry method according to GB / T21650.1-2008. The moisture permeability was tested according to GB / T21655.1-2008. A low-temperature environment simulation test was conducted, measuring the inner temperature after being kept at -30℃ for 2 hours.

[0157] The test results are shown in Table 1.

[0158]

[0159] As can be seen from Table 1, the fireproof and heat-insulating composite materials provided in Examples 1 to 3 have high maximum temperature resistance and low thermal conductivity. Moreover, the inner temperature is high after being kept at -30℃ for 2 hours, indicating that they have good high temperature resistance and heat insulation performance, thus ensuring high safety. They also have high tensile strength, indicating that they have good mechanical properties. Furthermore, they have high porosity and high moisture permeability, indicating that they have good air permeability and are more lightweight and comfortable.

[0160] Compared with Example 1, Examples 4 to 10 adjusted the type and mass ratio of continuous refractory fibers. It can be seen that when the continuous refractory fiber is a combination of high silica fiber, polycrystalline zirconia fiber and alumina fiber with a mass ratio of (4~6):(3~4):(1~2), the continuous refractory fiber has good high temperature resistance and flexibility, so that the resulting fireproof and heat-insulating composite material has good flame retardant and fireproof and heat insulation effects, and also has good comfort.

[0161] Compared with Example 1, Examples 11 and 12 respectively adjusted the diameter of the continuous refractory fiber. It can be seen that if the continuous refractory fiber is too fine, it is easy to sinter and agglomerate at high temperature and easy to melt and stick together at low temperature, which will reduce the high temperature resistance and make the thermal insulation structure prone to failure. If the continuous refractory fiber is too coarse, stress concentration will occur at high temperature, which will easily cause deformation and brittleness. In addition, the pores of the woven layer formed are too large, which will reduce the thermal insulation performance.

[0162] Compared with Example 1, Examples 13 and 14 respectively adjusted the loading amount of Mg / Al bimetallic hydroxide on the surface of the first continuous refractory fiber. It can be seen that if the loading amount of bimetallic hydroxide is too low, there will be too little interlayer water and hydroxyl water that can be released at high temperature, as well as too little carbon dioxide from the decomposition of interlayer carbonate and / or bicarbonate ions. The cooling effect will be weak, making it difficult to extinguish open flames in direct contact. At the same time, there are fewer binding sites with the continuous refractory fiber, which may cause it to fall off at high temperature. If the loading amount of bimetallic hydroxide is too high, it will block the micropore channels of the first braided layer, destroy its heat insulation structure, and reduce the heat insulation effect.

[0163] Compared with Example 1, Examples 15 and 16 respectively adjusted the mass ratio of flexible aerogel to the second braided layer. It can be seen that if the mass ratio of flexible aerogel to the second braided layer is too small, the heat insulation effect of flexible aerogel is not obvious, which affects the heat insulation performance of the inner layer. If the mass ratio of flexible aerogel to the second braided layer is too large, it will block the micropore channels of the second braided layer, destroy its heat insulation structure, and reduce the heat insulation effect.

[0164] Compared with Example 1, Examples 17 and 18 adjusted the volume ratio of tetraethyl orthosilicate and methyltrimethoxysilane, respectively. It can be seen that if the volume ratio of tetraethyl orthosilicate to methyltrimethoxysilane is too small, the mechanical strength of the silicon-oxygen skeleton of the flexible aerogel is too low, and it is prone to deformation and collapse under extreme conditions, making it unable to maintain a continuous porous structure, thus affecting the thermal insulation and heat preservation performance. If the volume ratio of tetraethyl orthosilicate to methyltrimethoxysilane is too large, the silicon-oxygen skeleton of the flexible aerogel is too dense, the thermal conductivity increases at high temperatures, the thermal insulation effect decreases, and the air permeability is poor, making it less lightweight.

[0165] Compared with Example 1, Comparative Example 1 and Comparative Example 2 used the fireproof and flame-retardant multilayer composite fabric for fire-fighting clothing disclosed in CN117465088A and the flame-retardant and heat-insulating fabric for fire-fighting clothing disclosed in CN120269888A, respectively. It can be seen that their overall performance is poor.

[0166] Compared with Example 1, in Comparative Example 3, since there is no in-situ epitaxial growth of bimetallic hydroxide on the surface of the first continuous refractory fiber of the first braided layer of the outer layer, it cannot further decompose and release water and carbon dioxide at high temperature, and therefore cannot actively cool down and extinguish open flames in direct contact, resulting in reduced high temperature resistance and safety performance.

[0167] Compared with Example 1, in Comparative Example 4, the cavity of the second braided layer of the inner layer lacks flexible aerogel, which cannot further ensure the thermal insulation balance of the inner layer, resulting in a decrease in its thermal insulation performance.

[0168] In summary, in this invention, both the first and second woven layers of the fireproof and heat-insulating composite material are made of continuous refractory fibers, which have good high-temperature resistance and uniform micropores, which are beneficial for flame retardancy, fire prevention, and heat insulation. The outer layer of bimetallic hydroxide can decompose and release interlayer water and hydroxyl water at high temperatures, and the carbonate and / or bicarbonate ions in the interlayer can decompose into carbon dioxide simultaneously, which can actively cool and extinguish open flames in direct contact. The inner layer of flexible aerogel provides balanced heat insulation and is lightweight and comfortable. The fireproof and heat-insulating composite material is connected by weaving and / or quilting, which can ensure interlayer stability and eliminate the risk of slippage and detachment. At the same time, it can avoid the use of polymer adhesives, has good air permeability, and will not decompose to produce toxic gases.

[0169] The fireproof, heat-insulating, and thermally insulating composite material provided by this invention has a maximum temperature resistance of ≥1050℃, thermal conductivity of ≤0.03W / (m·K), tensile strength of ≥15MPa, porosity of ≥85%, moisture permeability of ≥450g / (m2·24h), and an internal temperature of ≥10℃ after 2 hours of insulation at -30℃.

[0170] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A fireproof, heat-insulating, and thermally insulating composite material, characterized in that, The fireproof, heat-insulating, and thermally insulating composite material comprises an outer layer and an inner layer stacked together, wherein the outer layer and the inner layer are connected by weaving and / or quilting. The outer layer includes a first braided layer woven from a first continuous refractory fiber, wherein a bimetallic hydroxide is epitaxially grown in situ on the surface of the first continuous refractory fiber. The inner layer includes a second woven layer woven from a second continuous refractory fiber, and the surface and / or cavity of the second woven layer are provided with flexible aerogel. The interlayer anions of the bimetallic hydroxide include carbonate and / or bicarbonate ions.

2. The fireproof, heat-insulating, and thermally insulating composite material according to claim 1, characterized in that, The first continuous refractory fiber and the second continuous refractory fiber each independently comprise any one or a combination of at least two of high-silica fibers, polycrystalline zirconia fibers, or alumina fibers, preferably a combination of high-silica fibers, polycrystalline zirconia fibers, and alumina fibers. Preferably, in the combination of high-silica fibers, polycrystalline zirconia fibers and alumina fibers, the mass ratio of the high-silica fibers, polycrystalline zirconia fibers and alumina fibers is (4~6):(3~4):(1~2); Preferably, the diameters of the first continuous refractory fiber and the second continuous refractory fiber are independently 5μm to 10μm.

3. The fireproof, heat-insulating, and thermally insulating composite material according to claim 1 or 2, characterized in that, The bimetallic hydroxide includes any one or a combination of at least two of Mg / Al bimetallic hydroxide, Ca / Al bimetallic hydroxide, Ni / Al bimetallic hydroxide, or Ni / Fe bimetallic hydroxide; Preferably, the loading of the bimetallic hydroxide on the surface of the first continuous refractory fiber is 5 g / m². 2 ~20g / m 2 .

4. The fireproof thermal insulation composite material according to any one of claims 1 to 3, characterized in that, The flexible aerogel is a silicon-based aerogel; Preferably, the silicon source of the silicon-based aerogel includes any one or a combination of at least two of tetraethyl orthosilicate, methyltrimethoxysilane, dimethyldimethoxysilane or polyethoxysiloxane, preferably a combination of tetraethyl orthosilicate and methyltrimethoxysilane. Preferably, in the combination of tetraethyl orthosilicate and methyltrimethoxysilane, the volume ratio of tetraethyl orthosilicate to methyltrimethoxysilane is 1:(0.3~0.5); Preferably, the mass ratio of the flexible aerogel to the second woven layer is 1:(3~8).

5. The fireproof, heat-insulating, and thermally insulating composite material according to any one of claims 1 to 4, characterized in that, The first braided layer has a planar structure, and the second braided layer has a planar structure and / or a hollow structure; Preferably, the weaving method includes any one or a combination of at least two of plain weave, twill weave, or satin weave; Preferably, the quilting material comprises continuous refractory fiber; Preferably, the spacing between the quilted seams is 1cm to 3cm; Preferably, the stitch density of the quilting is 10 stitches / cm to 15 stitches / cm; Preferably, the second woven layer and the flexible aerogel are connected or fixed by quilting.

6. A method of producing a fireproof thermal insulation composite material as claimed in any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Outer layer preparation: The first continuous refractory fiber is woven to obtain the first woven layer; the first woven layer is placed in a bimetallic salt solution, and after vacuuming, an alkaline solution is added to carry out a co-precipitation reaction or a hydrothermal reaction, and a bimetallic hydroxide is epitaxially grown in situ on the surface of the first continuous refractory fiber to obtain the outer layer; (2) Inner layer preparation: The second continuous refractory fiber is woven to obtain the second woven layer; flexible aerogel is coated on the surface of the second woven layer, and / or flexible aerogel is filled into the cavity of the second woven layer, and aging treatment and drying are performed to obtain the inner layer; (3) Interlayer bonding: The outer layer and the inner layer are connected by weaving and / or quilting to obtain the fireproof and heat-insulating composite material.

7. The production method according to claim 6, wherein The bimetallic salt solution includes any one or a combination of at least two of nitrates, sulfates, or chlorides. Preferably, the metal ion pair in the bimetallic salt solution includes Mg. 2+ / Al 3+ Ca 2+ / Al 3+ Ni 2+ / Al 3+ or Ni 2+ / Fe 3+ Any one or at least two of them; Preferably, the total concentration of the metal ion pairs in the bimetallic salt solution is 0.1 mol / L to 0.5 mol / L; Preferably, in the metal ion pair, the molar ratio of the two metal ions is (1~2):(1~2); Preferably, the vacuuming process is carried out to an absolute pressure ≤133Pa; Preferably, the alkaline solution comprises any one or a combination of at least two of sodium carbonate, sodium bicarbonate, ammonia, or urea. Preferably, the concentration of the alkaline solution is 0.1 mol / L to 1 mol / L.

8. The preparation method according to claim 6 or 7, characterized in that, The preparation method of the flexible aerogel includes the following steps: A silicon source and an organic solvent are mixed to obtain a silicon source solution; an acid is added to the silicon source solution to adjust the pH once, and a hydrolysis reaction is carried out; then an alkali is added to adjust the pH a second time, and the mixture is stirred to obtain the flexible aerogel. Preferably, the organic solvent includes methanol; Preferably, the acid includes any one or a combination of at least two of hydrochloric acid, sulfuric acid, or nitric acid; Preferably, the concentration of the acid is 0.01 mol / L to 0.05 mol / L; Preferably, the first pH adjustment is to adjust the pH to 2-4; Preferably, the hydrolysis reaction takes 1 to 3 hours. Preferably, the alkali includes ammonia. Preferably, the concentration of the ammonia solution is 1 mol / L to 2 mol / L; Preferably, the secondary pH adjustment is to adjust the pH to 9-10; Preferably, the stirring speed is 300 rpm to 500 rpm; Preferably, the stirring time is 3 min to 15 min; Preferably, the silicon source solution further includes an additive, which includes any one or a combination of at least two of sodium bicarbonate, nano aluminum sol, or surfactant; Preferably, the additive accounts for 1 wt% to 3 wt% of the mass of the silicon source solution.

9. The method according to any one of claims 6 to 8, wherein the method further comprises the step of: Before the first braided layer is placed in the bimetallic salt solution, it further includes ultrasonic treatment and drying of the first braided layer; ​ Preferably, a flexible aerogel is coated on the surface of the second woven layer, and / or, before the flexible aerogel is filled into the cavity of the second woven layer, the second woven layer is further subjected to ultrasonic treatment and drying. Preferably, the solution used for ultrasonic treatment includes ethanol and / or acetone; Preferably, the ultrasonic treatment time is 15 min to 30 min; Preferably, the drying temperature is 60℃~100℃; Preferably, the drying time is 1 hour to 5 hours; Preferably, the temperature of the co-precipitation reaction is 10℃~80℃; Preferably, the coprecipitation reaction takes place over a period of 0.5 h to 24 h. Preferably, the temperature of the hydrothermal reaction is 70℃~250℃; Preferably, the hydrothermal reaction time is 5h to 36h; Preferably, the aging treatment temperature is 30℃~60℃; Preferably, the aging treatment time is 12h~24h; Preferably, the drying process includes supercritical carbon dioxide drying.

10. The application of the fireproof, heat-insulating, and thermally insulating composite material according to any one of claims 1 to 5, characterized in that, The fireproof, heat-insulating, and thermally insulating composite material is used for the outer fabric of fire-fighting suits, industrial high-temperature operation protective equipment, or protective equipment in extremely cold regions.

Images