Thermal insulation material based on thermal response nanoparticles and thermal radiation reflection and preparation method thereof

Abstract

The invention discloses a thermal insulation material based on thermal response nanoparticles and thermal radiation reflection and a preparation method thereof. Comprising a high-silica glass fiber cloth layer for high-temperature-resistant protection, and an aluminum silicate ceramic fiber felt layer for heat transfer and heat insulation, a polyphosphazene and organic silicon high-temperature adhesive layer for thermal response bonding and an aluminum foil layer for inhibiting thermal radiation reflection which are sequentially arranged in the high-silica glass fiber cloth layer. Efficient heat insulation can be achieved at the high temperature. The heat insulation mechanism is that heat transfer and heat radiation are inhibited; the high silica glass fiber cloth protects the internal structure and provides a high heat-resistant temperature; the aluminum silicate ceramic fiber felt inhibits heat conduction; a layer composed of the aluminum foil, the polyphosphazene and the high-temperature glue inhibits thermal radiation, and the thermal response nanoparticles can enhance the thermal insulation effect after being heated. And the polyphosphazene and the high-temperature glue form a bonding layer which is used for connecting the structures and assisting in shaping. The material is high in strength, heat insulation efficiency and heat-resistant temperature, the preparation process is simple and practical, the problem that heat radiation and heat transfer of a traditional material are difficult to restrain is solved, and a solution is provided for improving the heat insulation efficiency.

Description

Technical Field

[0001] The present invention relates to a technology in the field of thermal insulation materials, specifically a thermal insulation material based on thermal response nanoparticles and thermal radiation reflection and a preparation method thereof. Background Art

[0002] With the advancement of aerospace technology, numerous hypersonic aircraft have emerged. Among these, thermal protection issues in the leading edge of the fuselage and the bulkhead surrounding the engine have long been a significant constraint on aircraft speed and safety. Existing thermally conductive composite materials containing polyphosphazene, carbon-based fillers, and ceramic-based thermally conductive fillers have low thermal insulation performance. When subjected to external compression, the reduction in internal pores in the material significantly reduces its thermal insulation performance, rendering it unable to fully utilize its insulating properties when exposed to high-temperature heat sources. Summary of the Invention

[0003] In response to the problem that existing thermal insulation materials are difficult to suppress the thermal radiation heat transfer of traditional materials, the present invention proposes a thermal insulation material based on thermal responsive nanoparticles and thermal radiation reflection and a preparation method thereof, which has the advantages of high strength, high thermal insulation efficiency and high heat-resistant operating temperature; by achieving efficient thermal insulation of the thermal insulation material based on the strategy of suppressing heat conduction and thermal radiation, its preparation process has the characteristics of simple operation and strong practicality, providing a solution for improving the thermal insulation efficiency of thermal insulation materials.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention relates to a thermal insulation material based on thermally responsive nanoparticles and thermal radiation reflection, comprising: a high-silica glass fiber cloth layer for high-temperature protection, and an aluminum silicate ceramic fiber felt layer for heat transfer and insulation, a polyphosphazene and organosilicon high-temperature adhesive layer for thermally responsive bonding, and an aluminum foil layer for suppressing thermal radiation reflection, which are sequentially arranged inside the high-silica glass fiber cloth layer.

[0006] The heat-insulating material has an aluminum silicate ceramic fiber felt layer as the front side.

[0007] The length, width and thickness of the aluminum silicate ceramic fiber felt layer are 10*10*1 cm or 10*10*2 cm.

[0008] The mass ratio of polyphosphazene to organosilicon high temperature adhesive in the polyphosphazene and organosilicon high temperature adhesive layer is 1:2.

[0009] The thickness of the aluminum foil layer is 0.2 μm.

[0010] The thickness of the high silica glass fiber cloth layer is 0.25 mm and the density is 1000 kg / m 3 .

[0011] The invention relates to a method for preparing the above-mentioned thermal insulation material, which is obtained by placing aluminum foil on aluminum silicate ceramic fiber felt, completely wrapping it with high-silica glass fiber cloth, and sewing it with a mixture of polyphosphazene and organic silicon high-temperature adhesive, and finally curing it.

[0012] The curing process is as follows: curing at room temperature for 24 hours, curing at 100°C for 2 hours, and finally curing at 150°C for 2 hours.

[0013] Technical Effects

[0014] This invention utilizes thermally responsive nanoparticles and a thermal radiation reflective film as one of the raw materials for the thermal insulation material. High-silica glass fiber cloth protects the internal multi-layer insulation structure, providing ultra-high heat resistance. Aluminum silicate ceramic fiber felt inhibits heat conduction from the heat source. A thermal radiation suppression layer composed of aluminum foil, polyphosphazene, and high-temperature adhesive inhibits thermal radiation from the heat source, while the thermally responsive nanoparticle layer responds to heat and generates nanostructured particles to inhibit heat transfer. The polyphosphazene and high-temperature adhesive form an adhesive layer connecting the aluminum foil and the aluminum silicate ceramic fiber cloth. Furthermore, the high-silica glass fiber cloth and aluminum silicate ceramic fiber felt are also bonded and shaped with the high-temperature adhesive. Compared to existing technologies, this invention utilizes a composite method of newly synthesized nanoparticles with aluminum foil. Based on the strategy of inhibiting heat transfer and thermal composite materials, the invention introduces thermally responsive nanoparticles and a thermal radiation reflective film into the insulation material, enhancing the thermal insulation effect of the multi-layer composite insulation material. The resulting insulation material has a thermal insulation rate exceeding 90%. The prepared insulation material has advantages such as high strength, high thermal insulation efficiency, and a high heat resistance temperature. The preparation process is simple to operate and highly practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a physical diagram of the insulation material physical connection a (obtained in step 5.3) and the silicone high-temperature adhesive connection b (obtained in step 6.3);

[0016] In the figure: high temperature resistant protective layer 1, heat conductive heat insulating layer 2, thermal responsive adhesive layer 3 (also used for material bonding), heat radiation reflecting layer 4;

[0017] Figure 2 This is a diagram of the thermal insulation performance test device;

[0018] Figure 3 The actual nanoparticle polyphosphazene synthesized in the comparative example, and the SEM and TEM images of the polyphosphazene;

[0019] Figure 4 TG diagram of polyphosphazene of comparative example;

[0020] Figure 5 This is the thermal insulation performance diagram of the 2# and 3# thermal insulation materials obtained in step 2.2 of the comparative example at a hot surface temperature of 600°C;

[0021] Figure 6 This is the thermal insulation performance diagram of the 5# thermal insulation material obtained in step 5.3 of the comparative example at a hot surface temperature of 600°C;

[0022] Figure 7 This is the thermal insulation performance diagram of the thermal insulation material obtained in step 7.3 with a thickness of 2 cm and a hot surface temperature of 600°C for the comparative example. DETAILED DESCRIPTION

[0023] Example 1

[0024] This embodiment involves a method for preparing a thermal insulation material based on thermally responsive nanoparticles and thermal radiation reflection, specifically comprising:

[0025] Step 1: Add 2 g of polyphosphazene to a beaker;

[0026] Step 2: Add 4 g of high-temperature silicone glue to the beaker.

[0027] Step 3: Take 10*10 cm aluminum silicate ceramic fiber felt (1 cm thick) and aluminum foil;

[0028] In step 4, the aluminum silicate ceramic fiber felt (excluding the thermally responsive adhesive layer composed of polyphosphazene / silicone high-temperature adhesive) is completely wrapped with high-silica glass fiber cloth, and the high-silica glass fiber cloth and the aluminum silicate ceramic fiber felt are physically sutured and connected with high-temperature resistant wire; wherein the aluminum foil is placed on the top layer of the aluminum silicate ceramic fiber felt.

[0029] This embodiment uses a thermal insulation performance test device and a multi-channel temperature tester to measure the temperature change of the center point of the uppermost layer of the thermal insulation material. Figure 1 、 Figure 2 and Figure 6 As shown, the thermal insulation material prepared in this example had a top surface temperature of 128.1°C at the center after 1000 seconds of exposure to a 600°C heating temperature; after 1500 seconds, the temperature reached 130.7°C. Its thermal insulation efficiency after 1500 seconds was 78.2%. At 838.9 seconds, the temperature reached 125.5°C, representing a thermal insulation efficiency of 79.1%.

[0030] Example 2

[0031] This embodiment involves a method for preparing a thermal insulation material based on thermally responsive nanoparticles and thermal radiation reflection, specifically comprising:

[0032] Step 1: Add 2 g of polyphosphazene to a beaker;

[0033] Step 2: Add 4 g of high-temperature silicone glue to the beaker.

[0034] Step 3: Take 10*10 cm aluminum silicate ceramic fiber felt (1 cm thick) and aluminum foil;

[0035] Step 4: Placing aluminum foil on the top layer of the aluminum silicate ceramic fiber felt and bonding it with polyphosphazene / organic silicon high temperature adhesive to form a thermally responsive adhesive layer, then completely wrapping it with high-silica glass fiber cloth and bonding it externally with the polyphosphazene and organosilicone high temperature adhesive mixture prepared in Example 1;

[0036] Step 5: The multilayer composite thermal insulation material prepared above (including a high temperature resistant protective layer, a heat conductive insulation layer, a thermal responsive adhesive layer, and a heat radiation reflective layer) is first cured at room temperature for 24 hours, then cured at 100°C for 2 hours, and finally cured at 150°C for 2 hours.

[0037] This embodiment uses a thermal insulation performance test device and a multi-channel temperature tester to measure the temperature change of the center point of the top layer of the multi-layer composite thermal insulation material. Figure 1 、 Figure 2 and Figure 6 As shown in the figure, the temperature of the center of the upper surface of the thermal insulation material prepared in this example was 125.7°C after 1000 seconds of heating at 600°C. After 1500 seconds, the temperature was 130.2°C, and the thermal insulation efficiency after 1500 seconds was 78.3%. Specifically, the temperature reached 105.3°C at 838.9 seconds, indicating a thermal insulation efficiency of 82.5%.

[0038] Example 3

[0039] This embodiment involves a method for preparing a thermal insulation material based on thermally responsive nanoparticles and thermal radiation reflection, specifically comprising:

[0040] Step 1: Add 2 g of polyphosphazene to a beaker;

[0041] Step 2: Add 4 g of high-temperature silicone glue to the beaker.

[0042] Step 3: Take 10*10 cm aluminum silicate ceramic fiber felt (thickness 2 cm) and aluminum foil;

[0043] Step 4: placing aluminum foil on the top layer of the aluminum silicate ceramic fiber felt, then completely wrapping it with high-silica glass fiber cloth, and bonding it with the mixture of polyphosphazene and organosilicon high-temperature adhesive prepared in Example 1;

[0044] Step 5: The multilayer composite thermal insulation material prepared above (including a high temperature resistant protective layer, a heat conductive insulation layer, a thermal responsive adhesive layer, and a heat radiation reflective layer) is first cured at room temperature for 24 hours, then cured at 100°C for 2 hours, and finally cured at 150°C for 2 hours.

[0045] This embodiment uses a thermal insulation performance test device and a multi-channel temperature tester to measure the temperature change of the center point of the top layer of the multi-layer composite thermal insulation material. Figure 2 and Figure 7 As shown, the thermal insulation material prepared in this embodiment has a temperature of 53.5°C at the center of the upper surface when the surface is heated at 600°C for 1000 s; and a temperature of 58.9°C at 1500 s. The thermal insulation rate after 1500 s is 90.2%.

[0046] Comparative Example 1

[0047] This embodiment includes the following steps:

[0048] Step 1: synthesizing polyphosphazene, specifically comprising:

[0049] 1.1 Add 50 mL of tetrahydrofuran solvent into a two-necked flask;

[0050] 1.2 Dissolve hexachlorocyclotriphosphazene (0.5 g) and 4,4'-dihydroxydiphenyl sulfone (1.08 g) in tetrahydrofuran;

[0051] 1.3 Add 2 mL of triethylamine to the two-necked flask;

[0052] 1.4 Place the two flasks in water with an ultrasonic power of 50 W and a temperature of 50°C for polycondensation reaction for 5 hours;

[0053] 1.5 After the reaction is completed, wash with acetone and water three times each;

[0054] 1.6 Freeze-dry at -60 °C for 72 h to obtain a white solid product, polyphosphazene;

[0055] like Figure 3 As shown, the polyphosphazene synthesized in this example is a white cross-linked tube with a diameter of approximately 40 nm. When the white polyphosphazene containing heteroatoms is heated at 500°C, 700°C, and 900°C, it releases decomposition gases: 1. The white polyphosphazene inhibits the insulation material from absorbing the radiant heat from the heat source; 2. A temperature-responsive porous structure is formed in the organosilicon high-temperature adhesive, which improves the thermal insulation performance of the material; 3. The decomposed heteroatom gas can have a flame retardant effect.

[0056] Step 2: preparing thermal insulation materials, specifically comprising:

[0057] 2.1 Add 2 g of the polyphosphazene prepared in step 1 into a beaker;

[0058] 2.2 Add 4 g of high-temperature silicone rubber to the beaker;

[0059] 2.3 Take a 10*10*1 cm aluminum silicate ceramic fiber felt;

[0060] 2.4 The aluminum silicate ceramic fiber felt is completely wrapped with high-silica glass fiber cloth and bonded with the prepared polyphosphazene / organic silicon high-temperature adhesive mixture.

[0061] 2.5 The thermal insulation material prepared above was first cured at room temperature for 24 hours, then at 100°C for 2 hours, and finally at 150°C for 2 hours.

[0062] This embodiment uses a thermal insulation performance test device and a multi-channel temperature tester to measure the temperature change of the center point of the uppermost layer of the thermal insulation material. Figure 2 and Figure 5 As shown in Figure 2, the temperature of the center of the upper surface of the thermal insulation material obtained in step 2.2 was 156.4°C after 1000 seconds of heating at 600°C, and 162.9°C after 1500 seconds. The thermal insulation rate after 1500 seconds was 72.9%.

[0063] Comparative Example 2

[0064] In this embodiment, a single-layer thermal insulation material is prepared using a heat-conducting thermal insulation layer, specifically: 10*10*1 cm aluminum silicate ceramic fiber felt is taken.

[0065] This embodiment uses a thermal insulation performance test device and a multi-channel temperature tester to measure the temperature change of the center point of the uppermost layer of the thermal insulation material. Figure 2 and Figure 5 As shown in the graph, the temperature of the center of the upper surface of the thermal insulation material prepared in this example was 166.7°C after being heated at 600°C for 1000 seconds, and 189.6°C after 1500 seconds. The thermal insulation rate after 1500 seconds was 68.4%.

[0066] Comparative Example 3

[0067] This embodiment includes the following steps:

[0068] Step 1: Add 4 g of high-temperature silicone glue to a beaker.

[0069] Step 2: Take a 10*10*1 cm aluminum silicate ceramic fiber felt;

[0070] In step 3, the aluminum silicate ceramic fiber felt is completely wrapped with high-silica glass fiber cloth and bonded with the polyphosphazene prepared in Example 1 and the organic silicon high-temperature adhesive mixture.

[0071] Step 4: The thermal insulation material prepared above is first cured at room temperature for 24 hours, then cured at 100°C for 2 hours, and finally cured at 150°C for 2 hours.

[0072] This embodiment uses a thermal insulation performance test device and a multi-channel temperature tester to measure the temperature change of the center point of the uppermost layer of the thermal insulation material. Figure 2 and Figure 5 As shown, the thermal insulation material obtained in step 2 had a temperature of 153.4°C at the center of the upper surface after 1000 seconds at a temperature of 600°C; and 171.7°C after 1500 seconds. Its thermal insulation rate after 1500 seconds was 71.4%. The thermal insulation effect of Comparative Example 2 was slightly lower than that of this example at 1000 seconds, but after 1500 seconds, the thermal insulation effect of Example 2 was superior to that of this example. This is due to the porous effect of polyphosphazene decomposition and the suppression of thermal radiation.

[0073] In summary, the present invention utilizes a temperature-responsive / reflective thermal insulation material based on a strategy of suppressing heat conduction and heat radiation. By adopting a composite method of newly synthesized nanoparticles and heat radiation-reflecting aluminum foil, based on a strategy of suppressing heat transfer and heat radiation, heat-responsive nanoparticles and heat radiation-reflecting films are introduced into the thermal insulation material, thereby enhancing the thermal insulation effect of the multi-layer composite thermal insulation material. Compared with the prior art, the present invention enhances the thermal insulation performance by generating porous nano-cavities with organic silicon high-temperature adhesives when the temperature is too high. In addition, aluminum foil is introduced into the multi-layer thermal insulation material as a heat radiation reflector to suppress the radiation of radiant heat, thereby giving the thermal insulation material the function of suppressing heat transfer and heat radiation, and achieving the multi-layer temperature-responsive / reflective thermal insulation material with high-efficiency thermal insulation effect under high-temperature heat source conditions.

[0074] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principles and purpose of the present invention. The scope of protection of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. All implementation schemes within its scope shall be subject to the constraints of the present invention.

Claims

1. A thermal insulation material based on thermally responsive nanoparticles and thermal radiation reflection, characterized in that: include: A high-silica glass fiber cloth layer for high-temperature protection, and an aluminum silicate ceramic fiber felt layer for heat transfer and insulation, a polyphosphazene and silicone high-temperature adhesive layer for thermal response bonding, and an aluminum foil layer for suppressing thermal radiation reflection are sequentially arranged inside it.

2. The thermal insulation material based on thermal responsive nanoparticles and thermal radiation reflection according to claim 1, characterized in that: The heat-insulating material has an aluminum silicate ceramic fiber felt layer as the front side.

3. The thermal insulation material based on thermal responsive nanoparticles and thermal radiation reflection according to claim 1, characterized in that: The length, width and thickness of the aluminum silicate ceramic fiber felt layer are 10*10*1 cm or 10*10*2 cm.

4. The thermal insulation material based on thermal responsive nanoparticles and thermal radiation reflection according to claim 1, characterized in that: The mass ratio of polyphosphazene to organosilicon high temperature adhesive in the polyphosphazene and organosilicon high temperature adhesive layer is 1:

2.

5. The thermal insulation material based on thermal responsive nanoparticles and thermal radiation reflection according to claim 1, characterized in that: The thickness of the aluminum foil layer is 0.2 μm.

6. The thermal insulation material based on thermal responsive nanoparticles and thermal radiation reflection according to claim 1, characterized in that: The thickness of the high silica glass fiber cloth layer is 0.25 mm and the density is 1000 kg / m 3 .

7. A method for preparing the thermal insulation material according to any one of claims 1 to 6, characterized in that: The method is prepared by placing aluminum foil on aluminum silicate ceramic fiber felt, completely wrapping it with high-silica glass fiber cloth, stitching it with a mixture of polyphosphazene and organic silicon high-temperature adhesive, and finally curing it to obtain the product.

8. The method according to claim 7, wherein: The curing process is as follows: curing at room temperature for 24 hours, curing at 100°C for 2 hours, and finally curing at 150°C for 2 hours.

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