Preparation method of high-performance heat-insulation ablation-resistant aerogel composite material

Abstract

The invention discloses a preparation method of a high-performance heat-insulation ablation-resistant aerogel composite material. The preparation method comprises the following steps: firstly, preparing a glue solution, namely mixing a silicon source, ethanol, deionized water, ammonia water and ammonium fluoride in a certain proportion to prepare a silicon dioxide glue solution, wherein the ammonia water and the ammonium fluoride are used as catalysts; then putting a base material into the prepared silicon dioxide glue solution, modifying after the gel is aged, and finally drying to obtain an aerogel composite base material; and compounding resin or a resin plate with the aerogel composite base material in the previous step, curing at a certain temperature for a period of time, and circulating for multiple times to obtain the high-performance heat-insulating ablation-resistant aerogel composite material. The aerogel composite material can keep excellent ablation resistance and heat insulation performance in an extreme environment with high heat flux density, and a more reliable scheme is provided for equipment and structures in related fields in a high-temperature environment; and the adaptability is high, precise customized design and manufacturing can be carried out according to the shape and structure of equipment, and the requirements of different fields and equipment can be flexibly met.

Description

Technical Field

[0001] The present invention relates to the technical field of aerogel composite materials, and particularly to a preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material. Background Art

[0002] With the rapid development of modern technology, especially in the fields of aerospace, military, energy, and transportation, higher and higher requirements are put forward for the material properties under high-temperature environments. As a new type of lightweight and efficient heat-insulating material, aerogel has been widely used in high-temperature thermal protection systems in recent years due to its ultra-low density, high porosity, and excellent thermal insulation performance. Due to its low thermal conductivity, aerogel has significant advantages in the field of heat insulation, and is particularly suitable for high-temperature environments such as aerospace vehicles, rocket engines, and pipelines through which ultra-high-temperature gases flow.

[0003] The ablation phenomenon refers to the physical damage or chemical changes that occur on the surface or inside of a material due to the continuous action of heat flux density in a high-temperature environment, thereby affecting the performance and service life of the material. Although researchers have compounded aerogel with materials such as ceramic fibers, mineral fibers, and glass fibers, there are still deficiencies such as easy powder shedding, high brittleness, poor thermal shock resistance, and poor ablation performance. Especially in the face of the impact of high-temperature gas flow and continuous heat flux, the aerogel is prone to surface ablation, resulting in a rapid decline in its heat insulation effect. This has limited the development and application of related technologies to a certain extent. Therefore, it is crucial to develop an aerogel composite material with lightweight and high strength that can maintain excellent ablation resistance and heat insulation performance in extreme environments with high temperature and high heat flux density. Summary of the Invention

[0004] To overcome the deficiencies in the prior art, the present invention proposes a preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material to solve the problems of deficiencies in ablation resistance and heat insulation performance of traditional heat-insulating materials.

[0005] To solve the above technical problems, the present invention provides a preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material, including the following steps: Step A: Prepare the colloidal solution: Mix the silicon source, ethanol, deionized water, and catalyst in a certain proportion to prepare a silicon dioxide colloidal solution; wherein, the proportion of each component of the prepared colloidal solution is that the mass ratio of the silicon source: ethanol: deionized water: ammonia water: ammonium fluoride is 100: 50 - 1000: 0 - 30: 0 - 10: 0 - 10; Step B: Place the substrate in the prepared silicon dioxide colloidal solution, carry out modification after gel aging, and finally dry to obtain an aerogel composite base material; Step C: Compound the resin or resin plate with the aerogel composite base material in Step B, and then cure it at a certain temperature for a period of time, and repeat the cycle multiple times to obtain a high-performance heat-insulating and ablation-resistant aerogel composite material.

[0006] Preferably, the silicon source in step A is tetraethyl orthosilicate, ethyl silicate 40, or ethyl silicate 28, the catalyst is ammonia water and ammonium fluoride, and the ethanol content is 60.0-99.99%.

[0007] Preferably, the substrate in step B includes one of ceramics, glass, pre-oxidized fiber, carbon, alumina, mullite, quartz, graphite fiber felt, and melamine, polyester, polyether, polyethylene, ethylene vinyl acetate copolymer, polyurethane, nitrile foam, and its thickness is 0.1-100 mm.

[0008] Preferably, the substrates in step B are separated by one or more of non-woven fabric, monofilament filter cloth, spunlace cloth, fiber cloth, fiber paper, and polyethylene, polypropylene, polyester, polyamide mesh or film, and are slowly placed in the silica sol.

[0009] Preferably, the modifier for modification in step B is one of dimethyldiethoxysilane, trimethylchlorosilane, methyltriethoxysilane, hexamethyldisilazane, trimethylethoxysilane, octyltriethoxysilane, hexadecyltrimethoxysilane, and the modification time is 25-72 h.

[0010] Preferably, the drying method in step B is supercritical drying, freeze drying, vacuum drying or normal temperature and pressure drying.

[0011] Preferably, the aging time in step B is 12-72 h, and the drying time is 4-72 h.

[0012] Preferably, the resin in step C is one or more of phenolic, epoxy, polyester, vinyl ester, bismaleimide, polyimide, cyanate ester, melamine formaldehyde, furan, polybutadiene, silicone, modified resin. The resin is diluted with a corresponding diluent, and the mass ratio of the resin to the diluent is 5:0-5; the resin plate is cured from one or several of the resins.

[0013] Preferably, the composite method of the resin and the aerogel composite base material in step C is one or more of coating, impregnation, and spraying; the resin plate is combined with the aerogel composite base material through an adhesive.

[0014] Preferably, the curing temperature for the composite of the resin and the aerogel composite base material in step C is 20-300 °C, the curing time is 0.5-72 h, and the number of cycles is 0-15 times.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. The high-performance heat-insulating and ablation-resistant aerogel composite material prepared by the present invention combines a silica aerogel composite base material, a fiber felt substrate, and a resin layer, achieving an overall improvement in the properties of the material such as light weight, high strength, ablation resistance, and heat insulation. 2. The resin coating in the high-performance heat-insulating and ablation-resistant aerogel composite material prepared by the present invention can improve the problem of easy powder falling of the aerogel composite material; 3. The high-performance heat-insulating and ablation-resistant aerogel composite material can maintain excellent ablation resistance and heat-insulating performance in an extreme environment with a high heat flux density, providing a more reliable solution for equipment and structures in related fields under high-temperature environments; and it has strong adaptability, can be precisely customized and designed and manufactured according to the shape and structure of the equipment, and can flexibly meet the needs of different fields and equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the front view of the high-performance heat-insulating and ablation-resistant aerogel composite material prepared in Example 1 of the present invention before ablation; Figure 2 is the front view of the high-performance heat-insulating and ablation-resistant aerogel composite material prepared in Example 1 of the present invention after ablation; Figure 3 is the back view of the high-performance heat-insulating and ablation-resistant aerogel composite material prepared in Example 1 of the present invention after ablation. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The following further detailed description of the present invention is made in conjunction with the accompanying drawings and specific embodiments. According to the following description and the claims, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0018] In addition, the features, operations, and characteristics described in the specification can be combined in any suitable manner to form various embodiments. Similarly, the steps or actions described in the method can also be adjusted in the order that can be easily seen by those skilled in the art. Therefore, the various orders in the specification and the drawings are only for the purpose of clearly describing a certain embodiment, rather than the order that must be followed, unless it is stated that a certain order must be followed.

[0019] Example 1 Mix 200 g of tetraethyl orthosilicate with 588 g of ethanol, and then slowly add 32 g of deionized water under stirring; then, slowly add 2.4 g of ammonia water and 1.6 g of ammonium fluoride in sequence, and continuously stir for 5 min to obtain silica sol.

[0020] Then use non-woven fabric to separate the ceramic fiber felt layers, and then slowly immerse them in the above silica sol and compact them; then, gel and age at room temperature for 20 h, and then transfer them to a dimethyldiethoxysilane modification solution for modification for 40 h, and then transfer them to supercritical drying for drying for 8 h to obtain a ceramic fiber felt aerogel composite material.

[0021] Next, weigh 36 g of phenolic resin and dilute it with 4 g of absolute ethanol. Then, evenly coat the diluted resin on the surface of the above-mentioned ceramic fiber felt aerogel composite material, and then place it in an oven at 130 °C for 3 h to cure, obtaining a high-performance heat-insulating and ablation-resistant aerogel composite material.

[0022] Perform a high-temperature ablation experiment on the above-prepared high-performance heat-insulating and ablation-resistant aerogel composite material (with a thickness of 4.5 mm), using a butane flame spray gun (flame temperature is about 1200 - 1500 °C), and the gas consumption flow rate is 50 g / h. After ablation for 5 min, there is no cracking or delamination phenomenon, and it can maintain excellent ablation resistance. The mass ablation rate is 0.0062 g / s, and the maximum temperature on the cold surface is 261 °C.

[0023] Example 2 Mix 200 g of tetraethyl orthosilicate with 588 g of ethanol, and then slowly add 32 g of deionized water under stirring conditions; then, slowly add 2.4 g of ammonia water and 1.6 g of ammonium fluoride in sequence, and continuously stir for 5 min to obtain a silica sol.

[0024] Then, separate the ceramic fiber felt layers with non-woven fabric, and then slowly immerse it in the above silica sol and compact it; then, after gelling and aging at room temperature for 20 h, transfer it to a dimethyldiethoxysilane modification solution for modification for 40 h, and then transfer it to supercritical drying for drying for 8 h to obtain a ceramic fiber felt aerogel composite material.

[0025] (3) Weigh 36 g of phenolic resin, evenly coat it on the surface of the above-mentioned ceramic fiber felt aerogel composite material, and then place it in an oven at 130 °C for 2 h to cure, obtaining a high-performance heat-insulating and ablation-resistant aerogel composite material.

[0026] Perform a high-temperature ablation experiment on the above-prepared high-performance heat-insulating and ablation-resistant aerogel composite material (4.5 mm), using a butane flame spray gun (flame temperature is about 1200 - 1500 °C), and the gas consumption flow rate is 50 g / h. After ablation for 5 min, there is no cracking or delamination phenomenon, and it can maintain excellent ablation resistance. The mass ablation rate is 0.0057 g / s, and the maximum temperature on the cold surface is 255 °C.

[0027] Example 3 Mix 100 g of tetraethyl orthosilicate with 600 g of ethanol, and then slowly add 6.6 g of deionized water under stirring conditions; then, slowly add 4.2 g of ammonia water and 3.6 g of ammonium fluoride in sequence, and continuously stir for 5 min to obtain a silica sol.

[0028] Then, the ceramic fiber felt layers are separated by non-woven fabric, and then slowly immersed in the above-mentioned silica sol solution and compacted; then, after gelation and aging at room temperature for 18 h, it is transferred to a methyltriethoxysilane modification solution for modification for 40 h, and then transferred to supercritical drying for drying for 6 h to obtain a glass fiber felt aerogel composite material.

[0029] Then, 36 g of epoxy resin is weighed and diluted with 8 g of absolute ethanol. It is evenly coated on the surface of the above-mentioned glass fiber felt aerogel composite material, and then placed in an oven at 120 °C for curing for 2.5 h, and the coating is repeated twice to obtain a high-performance heat-insulating and ablation-resistant aerogel composite material. Example 4 100 g of tetraethyl orthosilicate is mixed with 400 g of ethanol, and then 9 g of deionized water is slowly added under stirring; then, 0.8 g of ammonia water and 0.6 g of ammonium fluoride are slowly added in sequence, and stirring is continued for 5 min to obtain a silica sol solution.

[0030] Then, the ceramic fiber felt layers are separated by non-woven fabric, and then slowly immersed in the above-mentioned silica sol solution and compacted; then, after gelation and aging at room temperature for 24 h, it is transferred to a methyltriethoxysilane modification solution for modification for 40 h, and then transferred to supercritical drying for drying for 10 h to obtain a glass fiber felt aerogel composite material.

[0031] Then, 36 g of phenolic resin is weighed and diluted with 6 g of absolute ethanol. It is evenly coated on the surface of the above-mentioned glass fiber felt aerogel composite material, and then placed in an oven at 120 °C for curing for 3 h to obtain a high-performance heat-insulating and ablation-resistant aerogel composite material.

[0032] The above description is only a description of the preferred embodiments of the present invention, and does not limit the scope of the present invention in any way. Any changes and modifications made by those of ordinary skill in the art of the present invention based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material, characterized in that, It includes the following steps: Step A: Configure the colloidal solution: Mix a silicon source, ethanol, deionized water, and a catalyst in a certain proportion to prepare a silica colloidal solution; among them, the proportion of each component in the prepared colloidal solution is that the mass ratio of the silicon source: ethanol: deionized water: ammonia water: ammonium fluoride is 100: 50 - 1000: 0 - 30: 0 - 10: 0 - 10; Step B: Place the substrate in the prepared silica colloidal solution, perform modification after gel aging, and finally dry it to obtain an aerogel composite base material; Step C: Composite the resin or resin plate with the aerogel composite base material in Step B, then place it at a certain temperature for curing for a period of time, and repeat the cycle multiple times to obtain a high-performance heat-insulating and ablation-resistant aerogel composite material.

2. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material as described in claim 1, wherein, The silicon source in Step A is tetraethyl orthosilicate, ethyl silicate 40, ethyl silicate 28, the catalyst is ammonia water and ammonium fluoride, and the ethanol content is 60.0 - 99.99%.

3. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material as described in claim 1, characterized in that, The substrate in Step B includes one of ceramics, glass, pre-oxidized fiber, carbon, alumina, mullite, quartz, graphite fiber felt, and melamine, polyester, polyether, polyethylene, ethylene vinyl acetate copolymer, polyurethane, nitrile foam, and its thickness is 0.1 - 100 mm.

4. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material according to claim 3, characterized in that, The substrates in Step B are separated by one or more of non-woven fabric, monofilament filter cloth, spunlace cloth, fiber cloth, fiber paper, and polyethylene, polypropylene, polyester, polyamide net or film, and are slowly placed in the silica colloidal solution.

5. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material according to claim 1, characterized in that, The modifier used for modification in Step B is one of dimethyldiethoxysilane, trimethylchlorosilane, methyltriethoxysilane, hexamethyldisilazane, trimethylethoxysilane, octyltriethoxysilane, hexadecyltrimethoxysilane, and the modification time is 25 - 72 h.

6. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material according to claim 1, wherein, The drying method in Step B is supercritical drying, freeze drying, vacuum drying or normal temperature and pressure drying.

7. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material according to claim 6, characterized in that The aging time in Step B is 12 - 72 h, and the drying time is 4 - 72 h.

8. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material according to claim 1, characterized in that, The resin in Step C is one or more of phenolic, epoxy, polyester, vinyl ester, bismaleimide, polyimide, cyanate ester, melamine formaldehyde, furan, polybutadiene, silicone, modified resin, and the resin is diluted with a corresponding diluent, and the mass ratio of the resin to the diluent is 5: 0 - 5; the resin plate is made by curing one or several of the resins.

9. The preparation method of a high-performance heat-insulating and ablation-resistant aerogel composite material according to claim 1, characterized in that, The composite method of the resin and the aerogel composite base material in Step C is one or more of coating, impregnation, spraying; the resin plate is composite with the aerogel composite base material through an adhesive.

10. The preparation method of a high-performance heat-insulating and ablative-resistant aerogel composite material according to claim 9, characterized in that, The curing temperature for the composite of the resin and the aerogel composite base material in Step C is 20 - 300 °C, the curing time is 0.5 - 72 h, and the number of cycles is 0 - 15 times.

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