High-temperature-resistant organic / inorganic composite silica aerogel material and preparation method thereof

Abstract

The application discloses a kind of high-temperature-resistant organic / inorganic composite silicon aerogel materials and preparation method thereof, high-temperature-resistant organic / inorganic composite silicon aerogel material includes nitrogen heterocyclic crown ether, MXene and organic silicon resin, its preparation process includes by MAX phase preparation MXene, and MXene is modified with nitrogen heterocyclic crown ether, nitrogen heterocyclic crown ether modified MXene is added to organic silicon resin, and high-temperature-resistant organic / inorganic composite silicon aerogel material is obtained.The high-temperature-resistant organic / inorganic composite silicon aerogel material prepared in the application has excellent high-temperature resistance and heat insulation performance, and can be widely used in 5G base station, semiconductor packaging, aerospace, nuclear industry, high-temperature battery, lightweight automobile and other fields, and has wide application prospect.

Description

A high-temperature resistant organic / inorganic composite silica aerogel material and its preparation method Technical Field

[0001] This invention relates to the field of high-temperature resistant materials technology, and in particular to a novel high-temperature resistant organic / inorganic composite silica aerogel material and its preparation method. Background Technology

[0002] In recent years, with the increasing demand for high-temperature materials, traditional high-temperature resistant materials (such as ceramics and metal alloys) have gradually revealed their limitations due to their high density and brittleness. Organosilicon resins, focusing on lightweight, functional, and multi-purpose high-temperature resistant polymers, have attracted much attention due to their excellent thermal stability and chemical durability. Organosilicon resins are widely used in high-temperature coatings, electronic packaging, and sealing materials due to their high-temperature resistance, weather resistance, and electrical insulation properties. However, when used alone, they still have the following problems: 1) Insufficient mechanical properties: Due to the flexibility of the silicon-oxygen backbone, the strength and toughness of the resin are relatively low; 2) Limited thermal conductivity and electrical properties: Although the silicon-oxygen structure is resistant to high temperatures, its thermal conductivity and dielectric properties are not high; 3) Limited stability under high-temperature environments: At extreme temperatures exceeding 400℃, its pyrolysis may affect its service life.

[0003] To address the aforementioned issues, organosilicon resins are improved in terms of high-temperature resistance and mechanical strength by introducing functional fillers (such as nanomaterials), modified groups (such as phenyl and fluorine groups), or by combining them with other high-performance materials. Chinese Patent CN103772735A discloses a method for preparing a heat-resistant porous bulk material of organosilicon resin reinforced with titanium dioxide nanoparticles. This method uses titanium dioxide nanoparticles with high refractive index as the reinforcing material, utilizing their high surface area and small size, and other nano-effects to control the formation of titanium dioxide nanoparticles with different crystal structures to reinforce the organosilicon porous material, thereby improving its structural stability at high temperatures. Chinese Patent CN102344569B provides a method for preparing a modified organosilicon resin and a coating containing the prepared modified organosilicon resin. This method uses terminal amino-terminated hyperbranched polyamide, epoxy resin, and organosilicon resin, along with a crosslinking catalyst, to react and obtain the modified organosilicon resin. This method combines the advantages of hyperbranched polyamide, epoxy resin, and organosilicon resin, achieving excellent heat resistance, good metal adhesion, low surface energy, excellent water resistance, and alkali resistance.

[0004] However, the above-mentioned single modification methods have limited effect on improving the mechanical properties, thermal conductivity, electrical properties and thermal stability of organosilicon resins. Therefore, the synergistic use of various modification methods to optimize the overall performance of organosilicon resins has become a research hotspot in recent years. Summary of the Invention

[0005] To address the limited performance improvement effect of the aforementioned single modification methods on organosilicon resins, this invention provides a new technical approach to improving the performance of organosilicon resins by combining azirconium crown ethers with two-dimensional MXene nanomaterials.

[0006] In a first aspect, the present invention provides a novel high-temperature resistant organic / inorganic composite silica aerogel material, comprising azircon ether, MXene and organosilicon resin.

[0007] This invention selects MXene from among many nanomaterials and introduces it into organosilicon resin for modification. MXene is a class of two-dimensional transition metal carbides or nitrides with unique structural and functional properties: 1) High thermal conductivity: Due to its metallic properties, MXene has extremely high thermal conductivity (approximately 30-50 W / m·K); 2) Excellent mechanical properties: The two-dimensional layered structure of MXene endows it with high strength and high elastic modulus, which can significantly enhance the mechanical properties of composite materials; 3) Surface functionalization: The surface of MXene often carries -OH, -F, or =O groups, which can form strong bonds with other materials (such as organosilicon resins or azeotropic crown ethers), improving interfacial stability. By constructing high thermal conductivity pathways, MXene can significantly improve the thermal management capability of composite materials. At high temperatures, the physical barrier formed between MXene layers can effectively inhibit the pyrolysis of the resin. The two-dimensional layered structure of MXene can improve the strength and modulus of composite materials, solving the mechanical property problems of organosilicon resins.

[0008] This invention selects azacrown ethers from among many modifiers, utilizing their nitrogen and oxygen groups to modify organosilicon resins. Azacrown ethers (Az) are cyclic compounds containing oxygen and nitrogen atoms, and their molecular structure has the following characteristics: 1) High coordination ability: The lone pair electrons of nitrogen and oxygen atoms enable them to effectively complex metal ions; 2) Structural stability: The cyclic structure has strong spatial rigidity, giving the material excellent thermal stability; 3) Multifunctionality: Azacrown ethers can introduce various groups through chemical modification, achieving synergistic effects with other materials. The rigid cyclic structure of azacrown ethers inhibits pyrolysis, significantly improving the high-temperature resistance of composite materials. As an interface material, azacrown ethers can enhance the bonding force between organosilicon resins and fillers (such as MXene) through complexation. The nitrogen and oxygen groups of azacrown ethers can improve the electrical conductivity or ionic conductivity of the material.

[0009] This invention introduces azeotropic crown ethers and MXene into silicone resins, resulting in a composite material that combines the three components and achieves synergistic effects by leveraging their respective advantages. Silicone resins provide basic thermal stability, and their silicon-oxygen bonds endow the material with fundamental high-temperature resistance. The functions of azeotropic crown ethers are: 1) By introducing a rigid cyclic structure and complexation, they further inhibit resin pyrolysis and improve the thermal stability of silicone resins; 2) As an interface stabilizer, azeotropic crown ethers enhance the interfacial bonding force of the material through chemical interaction with MXene and silicone resins, preventing delamination of the composite material under stress; 3) The lone pair electrons in the cyclic structure of azeotropic crown ethers synergistically interact with the metal layer of MXene to improve thermal conductivity; 4) The chemical bonding between azeotropic crown ethers and MXene surface groups (such as -OH) further enhances the material's antioxidant capacity. The functions of MXene are: 1) At high temperatures, MXene can form a multi-layered protective layer, preventing the escape of pyrolysis gases and enhancing the physical barrier effect in high-temperature environments; 2) The high strength and two-dimensional layered structure of MXene significantly improve the mechanical properties of composite materials; 3) The high thermal conductivity of MXene provides an efficient heat conduction path for composite materials. The multiphase interface structure formed by these three factors helps to improve the long-term stability of composite materials in high-temperature environments.

[0010] Secondly, this invention provides a method for preparing a novel high-temperature resistant organic / inorganic composite silica aerogel material, comprising the following steps:

[0011] Preparation of S1 and MXene

[0012] The MAX phase was added to a mixed solution of HCl and LiF for exfoliation to obtain a colloidal substance. The colloidal substance was filtered and washed, and then dispersed evenly in a solvent to obtain a suspension. The suspension was centrifuged and the supernatant was collected and dried to obtain MXene.

[0013] S2, Preparation of azacrown ethers

[0014] Ethylenediamine and anhydrous potassium carbonate were dissolved in a solvent and heated until fully dissolved to obtain a mixture. Glacial acetic acid was then added, followed by the slow addition of 1,2-dibromoethane to carry out the reaction. After the reaction, the mixture was allowed to stand and a precipitate was formed. The precipitate was filtered, dried, dissolved in a solvent, and sodium borohydride was added to obtain a clear solution. The clear solution was filtered, the solvent was evaporated, and deionized water was added to precipitate a white precipitate. The white precipitate was filtered and dried to obtain a white powdery azacrown ether.

[0015] S3, Preparation of MXene modified with azacrown ether

[0016] Solution A was obtained by dissolving the azacrown ether in a solvent, and suspension A was obtained by dispersing MXene in the solvent. Solution A was added dropwise to suspension A to carry out the reaction. After the reaction, the solution was centrifuged, washed and dried to obtain the azacrown ether modified MXene.

[0017] S4. Preparation of Organosilicon Resin

[0018] Methyltrimethoxysilane, phenyltrimethoxysilane, and tetramethoxysilane were reacted in the presence of a solvent and an acidic catalyst. After the reaction, the solvent was evaporated to obtain an organosilicon resin.

[0019] S5. Preparation of high-temperature resistant organic / inorganic composite silica aerogel materials

[0020] Organosilicon resin was dissolved in a solvent to obtain a resin solution. MXene modified with azacrown ether was slowly added to the resin solution and mixed evenly. Then, phenylsilane and Pt catalyst were added to carry out the reaction. The reaction product was dried to obtain a high-temperature resistant organic / inorganic composite silica aerogel material.

[0021] This invention modifies MXene with azacrown ether and then adds it to an organosilicon resin. During the modification reaction, the nitrogen and oxygen groups of the azacrown ether chemically bond with the -OH, -F, or =O groups on the MXene surface, such as: 1) Coordinate bond formation: The tertiary amine nitrogen (N) and ether oxygen (O) atoms in the azacrown ether provide lone pairs of electrons, which react with the residual transition metal ions (such as Ti) on the MXene surface. 3+ Al 3+ 1) Coordinate bonds are formed at Lewis acidic sites (such as Ti-F groups); the -OH group of MXene can form a hydrogen bond network with oxygen atoms in the crown ether ring, enhancing the interfacial bonding strength; 2) Nucleophilic substitution reaction: the amine group (-NH2) of the azeotropic crown ether attacks the -F group on the surface of MXene, undergoing nucleophilic substitution to generate stable Ti-N covalent bonds, while releasing HF. The modification of azeotropic crown ether can reduce the surface energy of MXene, making it uniformly dispersed in organosilicon resin and avoiding agglomeration. At the same time, the lamellar barrier effect of MXene and the char-forming characteristics of azeotropic crown ether work synergistically to significantly improve the flame retardant properties of composite silicone aerogel materials.

[0022] Preferably, in S1, the MAX phase is Ti3AlC2, the contents of HCl and LiF in the mixed solution of HCl and LiF are 3~5wt% and 5~10wt%, respectively, and the ratio of MAX phase to mixed solution of HCl and LiF is 20~25g:150~250mL.

[0023] Preferably, in S2, the proportions of ethylenediamine and potassium carbonate in the mixture are 2-8 wt% and 2-8 wt%, respectively; the volume ratio of ethylenediamine, glacial acetic acid, and 1,2-dibromoethane is 1-3 mL: 1-3 mL: 10-30 mL; the mass ratio of anhydrous potassium carbonate and sodium borohydride is 1-3: 0.5-2.5; the reaction temperature is 50-80℃; and the reaction time is 12-24 h.

[0024] Preferably, in S3, the mass ratio of azeotropic crown ether to MXene is 1:1~8; the reaction temperature is 50~80℃; and the reaction time is 4~6h.

[0025] Preferably, in S4, the acidic catalyst is a phosphoric acid solution with a concentration of 0.2~0.8wt%, the mass ratio of methyltrimethoxysilane, phenyltrimethoxysilane, and tetramethoxysilane is 2~5:1~1.5:1~1.5, the amount of phosphoric acid solution added is 5~10% of the total mass of methyltrimethoxysilane, phenyltrimethoxysilane, and tetramethoxysilane, the reaction temperature is 80~120℃, and the reaction time is 4~6h.

[0026] Preferably, in S5, the mass ratio of organosilicon resin, MXene modified with azacrown ether, and phenylsilane is 1:0.3~0.6:1~3, the amount of Pt catalyst added is 0.1~0.3% of the mass of organosilicon resin, the reaction temperature is 80~120℃, and the reaction time is 3~6h.

[0027] Preferably, in S5, the mass ratio of organosilicon resin, MXene modified with azacrown ether, and phenylsilane is 1:0.5:2.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] (1) Compared with single modified organosilicon resin, the novel high-temperature resistant organic / inorganic composite silicone aerogel material of the present invention significantly improves its high-temperature resistance and thermal insulation performance by leveraging the synergistic effect of organosilicon resin, azeotropic crown ether and MXene.

[0030] (2) Compared with single modified silicone resin, the novel high-temperature resistant organic / inorganic composite silicone aerogel material of the present invention has excellent thermal management capabilities, which can achieve reliable encapsulation under high temperature conditions in 5G base stations and semiconductor packaging; it can be used as a high-temperature protective coating in aerospace, nuclear industry and other fields, and can withstand high temperatures above 400°C; it can be used for the encapsulation and electrolyte of high-temperature batteries (such as sodium-ion batteries and solid-state batteries), so that it has both heat resistance and conductivity; it can replace traditional metal parts and be used in lightweight automotive and aerospace materials to meet the requirements of high temperature resistance and high strength, and its application fields are more extensive.

[0031] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0032] Figure 1 is a picture of the novel high-temperature resistant organic / inorganic composite silica aerogel material prepared in Example 1 burning under an open flame at 800°C;

[0033] Figure 2 is a picture of the novel high-temperature resistant organic / inorganic composite silica aerogel material prepared in Example 2 burning under an open flame at 800°C;

[0034] Figure 3 shows the thermogravimetric curve of the novel high-temperature resistant organic / inorganic composite silica aerogel material prepared in Example 1 at 800℃;

[0035] Figure 4 shows the thermogravimetric curve of the novel high-temperature resistant organic / inorganic composite silica aerogel material prepared in Example 2 at 800℃;

[0036] Figure 5 shows the back heating curve of the novel high-temperature resistant organic / inorganic composite silica aerogel material prepared in Example 1 under an open flame at 800℃.

[0037] Figure 6 shows the back-side temperature rise curve of the novel high-temperature resistant organic / inorganic composite silica aerogel material prepared in Example 2 under an open flame at 800℃. Detailed Implementation

[0038] The present invention will be further described below. It should be noted that this embodiment is based on the present technical solution and provides detailed implementation methods and specific operation processes, but the present invention is not limited to this embodiment.

[0039] Example 1

[0040] This embodiment provides a method for preparing a novel high-temperature resistant organic / inorganic composite silica aerogel material, including the following steps:

[0041] Preparation of S1 and MXene

[0042] 22.5 g of Ti3AlC2 (MAX phase) was added to 200 mL of a mixed solution of HCl and LiF (containing 3.5 wt% HCl and 5 wt% LiF). The solution was stirred at room temperature for about 8 hours, and the solution changed from a suspended powder to a colloidal substance (indicating that the MAX phase was successfully exfoliated and the aluminum in the MAX phase could be completely extracted and dissolved). The colloidal substance was filtered and washed three times with distilled water and ethanol until the pH value dropped to neutral. The MXene obtained by filtration and washing was placed in 10 mL of isopropanol and sonicated for 1.5 h to form a thick suspension. Then, it was centrifuged at 800 rpm for 20 min. The upper MXene solution was taken and vacuum dried at 65 °C for 5 h to obtain MXene.

[0043] S2, Preparation of azacrown ethers

[0044] 1.75 g of ethylenediamine and 1.4 g of anhydrous potassium carbonate were added to a three-necked flask containing 35 mL of methanol and heated in an oil bath at 55 °C until fully dissolved. 1.25 mL of glacial acetic acid was added to the flask, followed by the slow addition of 10 mL of 1,2-dibromoethane. After reacting for 16 h, an orange solution was obtained. After standing for 6 h, a precipitate was formed. The precipitate was filtered, dried, and then dissolved in 20 mL of methanol. 1.25 g of sodium borohydride was added to obtain a clear solution. After filtering the clear solution, the solvent was evaporated until 5 mL of solution remained. 30 mL of deionized water was added to precipitate a white precipitate. After standing for 15 h, the precipitate was filtered to obtain a white powdery azacrown ether.

[0045] S3, Preparation of MXene modified with azacrown ether

[0046] 1.25 g of azacrown ether was dissolved in 50 mL of toluene to obtain solution A, and 7.5 g of MXene was dissolved in 100 mL of isopropanol to obtain suspension A. Solution A was added dropwise to suspension A, and the resulting mixture was reacted at 55 °C for 5 h. The nitrogen and oxygen groups of the azacrown ether chemically bonded with the -OH, -F or =O groups on the surface of MXene to complete the modification of MXene by the azacrown ether. After the reaction, the mixture was centrifuged, washed to remove unreacted azacrown ether, and dried to obtain azacrown ether modified MXene.

[0047] S4. Preparation of Organosilicon Resin

[0048] Using 75 mL of ethanol as solvent, 22 g of methyltrimethoxysilane, 13.5 g of phenyltrimethoxysilane, and 13.5 g of tetramethoxysilane were added to a reaction vessel, followed by the slow addition of 3.5 g of 0.5 wt% phosphoric acid solution. The mixture was heated to 100 °C and reacted for 5 h. After the reaction, the solvent was evaporated to obtain the organosilicon resin.

[0049] S5. Preparation of novel high-temperature resistant organic / inorganic composite silica aerogel materials

[0050] 12.5g of organosilicon resin was dissolved in 100mL of cyclohexanone to obtain a resin solution. 6.5g of MXene modified with azacrown ether was slowly added to the resin solution, stirred evenly, and ultrasonically dispersed for 15min. Then, 30g of phenylsilane and 0.2g of Pt catalyst were added and stirred at 100℃ for 4h. The reaction product was supercritically dried for 8h to obtain a novel high-temperature resistant organic / inorganic composite silica aerogel material.

[0051] Example 2

[0052] This embodiment provides a method for preparing a novel high-temperature resistant organic / inorganic composite silica aerogel material, including the following steps:

[0053] Preparation of S1 and MXene

[0054] 25g of Ti3AlC2 (MAX phase) was added to 200mL of a mixed solution of HCl and LiF (containing 5wt% HCl and 10wt% LiF). The solution was stirred at room temperature for about 9 hours, and the solution changed from a suspended powder to a colloidal substance (indicating that the MAX phase was successfully exfoliated and the aluminum in the MAX phase could be completely extracted and dissolved). The colloidal substance was filtered and washed 5 times with distilled water and ethanol until the pH value dropped to neutral. The MXene obtained by filtration and washing was placed in 15mL of isopropanol and sonicated for 3h to form a thick suspension. Then, it was centrifuged at 1000rpm for 30min, and the upper MXene solution was taken and vacuum dried at 80℃ for 6h to obtain MXene.

[0055] S2, Preparation of azacrown ethers

[0056] 2.5 g of ethylenediamine and 3.0 g of anhydrous potassium carbonate were added to a three-necked flask containing 50 mL of methanol and heated in an oil bath at 80 °C until fully dissolved. 3 mL of glacial acetic acid was added to the three-necked flask, followed by the slow addition of 30 mL of 1,2-dibromoethane. After reacting for 24 h, an orange solution was obtained. After standing for 8 h, a precipitate was precipitated. The precipitate was filtered, dried, and then dissolved in 30 mL of methanol. 2.5 g of sodium borohydride was added to obtain a clear solution. After filtering the clear solution, the solvent was evaporated until 10 mL of solution remained. 50 mL of deionized water was added to precipitate a white precipitate. After standing for 24 h, the precipitate was filtered to obtain a white powdery azacrown ether.

[0057] S3, Preparation of MXene modified with azacrown ether

[0058] 4.2 g of azacrown ether was dissolved in 75 mL of toluene to obtain solution A, and 8.5 g of MXene was dissolved in 100 mL of isopropanol to obtain suspension A. Solution A was added dropwise to suspension A, and the resulting mixture was reacted at 80 °C for 6 h. The nitrogen and oxygen groups of the azacrown ether chemically bonded with the -OH, -F or =O groups on the surface of MXene to complete the modification of MXene by the azacrown ether. After the reaction, the mixture was centrifuged, washed to remove unreacted azacrown ether, and dried to obtain azacrown ether modified MXene.

[0059] S4. Preparation of Organosilicon Resin

[0060] Using 100 mL of ethanol as solvent, 40 g of methyltrimethoxysilane, 14.5 g of phenyltrimethoxysilane, and 12.5 g of tetramethoxysilane were added to a reaction vessel, and then 4.0 g of 0.75 wt% phosphoric acid solution was slowly added. The temperature was raised to 120 °C and the reaction was carried out for 6 h. After the reaction, the solvent was evaporated to obtain organosilicon resin.

[0061] S5. Preparation of novel high-temperature resistant organic / inorganic composite silica aerogel materials

[0062] 17.5g of organosilicon resin was dissolved in 100 mL of cyclohexanone to obtain a resin solution. 8.5g of MXene modified with azacrown ether was slowly added to the resin solution, stirred until homogeneous, and ultrasonically dispersed for 30 min. Then, 38.5g of phenylsilane and 0.25g of Pt catalyst were added and stirred at 120℃ for 6 h. The reaction product was supercritically dried for 8 h to obtain a novel high-temperature resistant organic / inorganic composite silica aerogel material.

[0063] Comparative Example 1

[0064] The difference between this comparative example and Example 1 is that the organosilicon resin obtained in step S4 is used directly as the composite silicone aerogel material.

[0065] Comparative Example 2

[0066] The difference between this comparative example and Example 1 is that in step S5, the nitrogen crown ether modified Mxene was not added, but instead replaced with Mxene.

[0067] Comparative Example 3

[0068] The difference between this comparative example and Example 1 is that in step S5, Mxene modified with azacrown ether was not added, but was replaced with azacrown ether.

[0069] Comparative Example 4

[0070] The difference between this comparative example and Example 1 is that the preparation process of the azacrown ether modified Mxene is different. In this comparative example, the azacrown ether and Mxene are directly added to the organosilicon resin. The specific preparation process is as follows:

[0071] 12.5g of organosilicon resin was dissolved in 100mL of cyclohexanone to obtain a resin solution. 1.25g of azircon ether and 7.5g of MXene were slowly added to the resin solution and stirred until homogeneous. The mixture was then ultrasonically dispersed for 15min. 30g of phenylsilane and 0.2g of Pt catalyst were added and the mixture was stirred at 100℃ for 4h. The reaction product was supercritically dried for 8h to obtain an organic / inorganic composite silica aerogel material.

[0072] Experimental Example 1

[0073] (1) Thermal stability test

[0074] Samples 1 and 2 with dimensions of 50×10×10mm were prepared using the materials obtained in Examples 1 and 2, respectively. Vertical combustion tests were conducted on the samples according to the GB / T10707-2008 standard, and the results are shown in Figures 1 and 2.

[0075] As can be seen from Figures 1 and 2, after 10 seconds of combustion, samples 1 and 2 burned on their own. Within 30 seconds, the flame gradually extinguished and disappeared. During the entire combustion process, no molten droplets appeared, indicating that the novel high-temperature resistant organic / inorganic composite silica aerogel materials prepared in Examples 1 and 2 have excellent thermal stability.

[0076] (2) Determination of weight loss curve

[0077] Weigh 8g of the material obtained in Examples 1 and 2 respectively, place it in a thermogravimetric analyzer, set the heating rate to 10℃ / min, and heat it from room temperature to 750℃. The resulting thermogravimetric curves are shown in Figures 3 and 4.

[0078] As can be seen from Figures 3 and 4, the novel high-temperature resistant organic / inorganic composite silica aerogel materials prepared in Examples 1 and 2 only showed weight loss at temperatures above 400°C. The novel high-temperature resistant organic / inorganic composite silica aerogel materials prepared in Examples 1 and 2 had maximum residual weights of 94.95% and 93.38% at 750°C, respectively, indicating that the novel high-temperature resistant organic / inorganic composite silica aerogel materials prepared in Examples 1 and 2 can withstand temperatures above 400°C.

[0079] (3) Temperature sensing test

[0080] Samples 3 and 4 with dimensions of 200×200×10mm were prepared using the materials obtained in Examples 1 and 2, respectively. The front of the two samples was heated with an open flame at 800℃, and the temperature change of the back of the samples over time was measured using a temperature sensor. The results are shown in Figures 5 and 6.

[0081] Samples 5-8 with dimensions of 200×200×10mm were prepared using the materials obtained from Comparative Examples 1-4. The front of the four samples was heated at 800℃ with an open flame, and the temperature change of the back of the samples over time was measured using a temperature sensor. The temperature sensing test results of the materials prepared in Examples 1-2 and Comparative Examples 1-4 within 30 minutes are shown in Table 1.

[0082] Table 1 Temperature Sensing Test Results

[0083]

[0084] As can be seen from Figures 5-6 and Table 1, as the heating time increases, the back surface temperature of the samples prepared in Examples 1-2 does not exceed 150°C within 30 minutes, while the back surface temperature of the samples prepared in Comparative Examples 1-4 is higher than 170°C. This indicates that the novel high-temperature resistant organic / inorganic composite silica aerogel material prepared in this invention significantly improves its high-temperature resistance and thermal insulation performance by leveraging the synergistic effect of organosilicon resin, azirconium crown ether, and MXene.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A high-temperature resistant organic / inorganic composite silica aerogel material, characterized in that: The invention comprises azeotropic crown ether, MXene, and organosilicon resin; the preparation method of the high-temperature resistant organic / inorganic composite silica aerogel material includes the following steps: S1, Preparation of MXene: The MAX phase is added to a mixed solution of HCl and LiF for exfoliation to obtain a colloidal substance. The colloidal substance is filtered and washed, then dispersed evenly in a solvent to obtain a suspension. The suspension is centrifuged and the supernatant is collected and dried to obtain MXene; S2, Preparation of azeotropic crown ether: Ethylenediamine and anhydrous potassium carbonate are dissolved in methanol and heated. After complete dissolution to obtain a mixed solution, glacial acetic acid is added, and then 1,2-dibromoethane is slowly added dropwise for reaction. After the reaction, the precipitate is allowed to stand and precipitate. The precipitate is filtered, dried, dissolved in methanol, and sodium borohydride is added to obtain a clear solution. The clear solution is filtered, the solvent is evaporated, and deionized water is added to precipitate a white precipitate. The white precipitate is filtered and dried to obtain a white powdered azeotropic crown ether; S3, Preparation of azeotropic crown ether-modified MXene: The azeotropic crown ether is dissolved in a solvent to obtain... In solution A, MXene is dispersed in a solvent to obtain suspension A. Solution A is added dropwise to suspension A to carry out the reaction. After the reaction, centrifugation, washing, and drying are performed to obtain MXene modified with azacrown ether. S4: Preparation of organosilicon resin. Methyltrimethoxysilane, phenyltrimethoxysilane, and tetramethoxysilane are reacted in the presence of a solvent and an acidic catalyst. After the reaction, the solvent is evaporated to obtain organosilicon resin. S5: Preparation of high-temperature resistant organic / inorganic composite silica aerogel material. Organosilicon resin is dissolved in a solvent to obtain a resin solution. Azacrown ether modified MXene is slowly added to the resin solution and mixed evenly. Then, phenylsilane and a Pt catalyst are added to carry out the reaction. The reaction product is dried to obtain high-temperature resistant organic / inorganic composite silica aerogel material. In S3, the mass ratio of azacrown ether to MXene is 1:1~8. In S5, the mass ratio of organosilicon resin, azacrown ether modified MXene, and phenylsilane is 1:0.3~0.6:1~3.

2. The high-temperature resistant organic / inorganic composite silica aerogel material according to claim 1, characterized in that: In S1, the MAX phase is Ti3AlC2, and the contents of HCl and LiF in the mixed solution of HCl and LiF are 3~5wt% and 5~10wt%, respectively. The ratio of MAX phase to mixed solution of HCl and LiF is 20~25g:150~250mL.

3. The high-temperature resistant organic / inorganic composite silica aerogel material according to claim 1, characterized in that: In S2, the proportions of ethylenediamine and potassium carbonate in the mixed solution are 2~8wt% and 2~8wt%, respectively. The volume ratio of ethylenediamine, glacial acetic acid and 1,2-dibromoethane is 1~3:1~3:10~30, and the mass ratio of anhydrous potassium carbonate and sodium borohydride is 1~3:0.5~2.

5. The reaction temperature is 50~80℃, and the reaction time is 12~24h.

4. The high-temperature resistant organic / inorganic composite silica aerogel material according to claim 1, characterized in that: In S3, the reaction temperature is 50~80℃ and the reaction time is 4~6h.

5. The high-temperature resistant organic / inorganic composite silica aerogel material according to claim 2, characterized in that: In S4, the acidic catalyst is a phosphoric acid solution with a concentration of 0.2~0.8wt%, the mass ratio of methyltrimethoxysilane, phenyltrimethoxysilane, and tetramethoxysilane is 2~5:1~1.5:1~1.5, and the amount of phosphoric acid solution added is 5~10% of the total mass of methyltrimethoxysilane, phenyltrimethoxysilane, and tetramethoxysilane; the reaction temperature is 80~120℃, and the reaction time is 4~6h.

6. The high-temperature resistant organic / inorganic composite silica aerogel material according to claim 1, characterized in that: In S5, the amount of Pt catalyst added is 1-3% of the mass of the organosilicon resin; the reaction temperature is 80-120℃, and the reaction time is 3-6h.

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