A heat-processed type adherable aerogel capsule and a preparation method and application thereof

Abstract

The application discloses a kind of hot processing type can be adhered aerogel capsule and its preparation method and application, the capsule uses porous chitosan / silicon aerogel as the heat-insulating core of ultra-low density, and is coated with a layer of by chitosan and carboxylated rubber emulsion electrostatic self-assembly formed anion complex shell, realize core-shell structure.The capsule can be activated self-stick under mild heating (≤80 ℃) condition, and multiple capsules can be fused and bonded to form a three-dimensional overall structure, and can be attached to various irregular surfaces or substrates.The capsule of the application has strong adhesion, good self-stick / foreign-stick performance, while maintaining the ultra-low density and excellent thermal insulation performance of aerogel material, and has ultra-high flame retardance.In the field of building energy saving, on-site thermal insulation and fire prevention, the application has wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of aerogel composite materials technology, and more specifically, to a thermally processable adhesive aerogel capsule, its preparation method, and its application. Background Technology

[0002] Aerogels are renowned for their ultra-low density and excellent thermal insulation properties, leading to their wide application in modern engineering. Since the first aerogel was prepared via supercritical drying in 1931, various methods for aerogel preparation and molding have been developed, including 3D printing of organic / inorganic materials and aerogel slurry molding. However, the interfacial integration of traditional aerogels with other substrates has long been a challenge. This is mainly due to the highly porous surface of aerogels, resulting in a small actual contact area; simultaneously, their inherent rigid framework restricts molecular chain movement, lacking the molecular entanglement or chemical bonding required for strong adhesion. Traditional aerogels cannot simultaneously possess both high thermal insulation and easy processing and adhesion, but designing them as core-shell structures promises to achieve both.

[0003] In summary, existing technologies lack a material that can maintain the ultra-low density and thermal insulation advantages of aerogels while also possessing good self-adhesion capabilities and being easily processed and shaped through heating. This invention addresses this issue by providing a thermally processable, adhesive aerogel capsule. Through an innovative core-shell composite structure and preparation process, it achieves interfacial adhesion and processability of the aerogel material.

[0004] Patent 201710024728.1 discloses a method for preparing silica aerogel microcapsules by complex condensation. Although it also uses chitosan to obtain a core-shell structure, its preparation process is complex, time-consuming, and cannot be thermally activated. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a thermally processable adhesive aerogel capsule, its preparation method, and its application, overcoming the shortcomings of traditional aerogels in terms of adhesion and processing, thereby achieving self-adhesive assembly and heterogeneous surface adhesion of aerogel materials, while maintaining their excellent properties such as lightweight, high thermal insulation, and flame retardancy.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A heat-processable adhesive aerogel capsule includes a porous, heat-insulating core and a gelatinous shell covering the core; the core comprises a porous network structure formed by a composite of silica-based aerogel and chitosan; the shell is composed of a polyelectrolyte complex formed by the electrostatic interaction of chitosan and carboxylated rubber latex, and is tightly attached to the surface of the core.

[0008] Preferably, the carboxylated rubber latex includes one or more of carboxylated nitrile rubber latex, carboxylated styrene-butadiene rubber latex, and hydrogenated carboxylated nitrile rubber latex.

[0009] Preferably, the capsule is spherical or nearly spherical in shape and has a density of 50–100 mg / cm³. 3 The shell thickness is 2–10 μm.

[0010] Preferably, multiple capsules can be bonded together to form an integral structure at a temperature of ≤80°C.

[0011] Preferably, the capsule shell is formed by the self-assembly of protonated chitosan cations and deprotonated carboxylated rubber latex anions under pH 4–7 conditions.

[0012] This application also provides a method for preparing the above-described heat-processable adhesive aerogel capsule, comprising the following steps:

[0013] a. Dissolve chitosan in an acidic aqueous solution to prepare a chitosan solution, and mix it with silica aerogel powder to form a uniform slurry;

[0014] b. Add the slurry droplets to the stirred carboxylated rubber latex to form a chitosan-carboxylated rubber latex polyelectrolyte composite shell on the droplet surface, thus obtaining a wet capsule;

[0015] c. Freeze-dry the obtained wet capsules to remove moisture and obtain the aerogel capsules.

[0016] Preferably, in step a, the concentration of the chitosan solution is 5–10 wt%.

[0017] Preferably, in step b, the concentration of the carboxylated rubber emulsion is 15-70 wt%, the pH value of the carboxylated rubber emulsion is adjusted to 4-7, and the stirring time is 2-60 minutes.

[0018] Preferably, in step b, the slurry dripping speed is controlled at 1 drop / second, and multiple points are injected simultaneously during the dripping process to improve preparation efficiency.

[0019] In addition, this application also provides an application of the above-described heat-processable adhesive aerogel capsule in the fields of heat insulation, heat preservation, fireproofing, and cushioning protection.

[0020] The beneficial effects of this invention are as follows:

[0021] 1. The preparation method of the present invention is simple and efficient, requiring no complicated preparation steps, no long-term heating, stirring, or other auxiliary agents, providing a green, efficient, and low-cost production path.

[0022] 2. The core-shell structure design employed in this invention effectively separates adhesion and insulation functions: the porous aerogel core provides ultra-lightweight properties and high thermal insulation, while the shell imparts excellent interfacial adhesion and thermal processing capabilities. Compared to traditional aerogels, the capsules of this invention can self-bond and form at low temperatures (not exceeding 80°C) through heating, without the need for adhesives or complex processes. Multiple capsules can be melted and assembled into a single structure or applied to the surface of other objects. Its adhesion strength can reach tens of kPa (self-adhesive shear strength up to approximately 55 kPa), and it can firmly adhere to various heterogeneous substrates, including wood, metal, plastics, and rubber. The assembled aerogel material still maintains a low thermal conductivity of approximately 0.031–0.039 W / m·K.

[0023] 3. The micron-sized outer shell can rapidly form a carbon layer under a butane spray gun, and the core consists of an inorganic silicon framework and a chitosan framework. The capsule exhibits extremely high resistance to open flames, undergoing only surface charring during combustion without supporting combustion, thus possessing excellent flame-retardant properties. This invention has unique advantages and potential application value in on-site thermal management, energy-saving insulation, and fire protection. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the core-shell structure of the aerogel capsule prepared in Example 1 of the present invention;

[0025] Figure 2 This is a schematic diagram of the preparation process of the aerogel capsule in Embodiment 1 of the present invention;

[0026] Figure 3 This is a schematic diagram of the self-adhesive assembly of the aerogel capsule in Embodiment 1 of the present invention;

[0027] Figure 4 This is a schematic diagram of the self-adhesive assembly of the aerogel capsule in Embodiment 1 of the present invention;

[0028] Figure 5 This is a schematic diagram showing the adhesion of the aerogel capsule in Embodiment 1 of the present invention to different substrate surfaces;

[0029] Figure 6 A schematic diagram of the flame-retardant effect of the aerogel capsule in Embodiment 1 of the present invention. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Based on the embodiments in this application, other similar embodiments obtained by those skilled in the art without creative effort should all fall within the scope of protection of this application.

[0031] Raw materials: chitosan (degree of deacetylation ≥88%, molecular weight ≤300,000), hydrophobically modified silica aerogel powder (hydrophobicity ≥95%), carboxylated nitrile butadiene rubber latex (industrial latex), carboxylated styrene-butadiene rubber latex (industrial latex), carboxylated hydrogenated nitrile butadiene rubber latex (industrial latex), natural rubber latex, butyl rubber latex, glacial acetic acid, deionized water, etc.

[0032] Example 1:

[0033] A method for preparing thermally processable adhesive aerogel capsules, the process flow is as follows: Figure 2 As shown, the specific steps include:

[0034] 1. Preparation of Chitosan Solution (CTS): Chitosan was dissolved in a dilute deionized aqueous solution of acetic acid to prepare a 5 wt% acidic chitosan solution. The pH of this acidic chitosan solution was 4 (the pH can be controlled within the range of 4–7 by adjusting the amount of acetic acid used as needed). Under these acidic conditions, most of the amino groups (–NH2) in chitosan were protonated to –NH3. + Therefore, chitosan molecules carry a positive charge. The amino pKa of chitosan is approximately 6.3. According to the Henderson-Hasselbalch equation: pH = pKa + log([–NH2] / [–NH3) + It can be estimated that at pH 4.0, the protonation degree α of chitosan amino groups is close to 99% (almost entirely as –NH3). + Even at a slightly acidic pH of 5.5, approximately 96% of the amino groups remain protonated. This ensures a high density of positive charges in the chitosan solution, which is beneficial for the subsequent formation of a stable polyelectrolyte complex shell.

[0035] 2. Preparation of Chitosan / Aerogel Slurry: Hydrophobic silica aerogel powder is added to the chitosan solution while stirring slowly, ensuring the aerogel particles are fully wetted and dispersed in the chitosan solution to form a uniform slurry. Preferably, the amount of aerogel added is sufficient to form a uniform suspension with moderate viscosity. In this embodiment, 0.1g of aerogel powder (corresponding to a chitosan concentration of 5%) is added to 20g of chitosan solution, under which the slurry is uniform and viscous. Adding too much aerogel will result in uneven slurry formation and particle floating; adding too little will prevent the aerogel from fully occupying the core, affecting capsule performance.

[0036] 3. Emulsion self-assembly into a shell: The prepared CTS / aerogel slurry is loaded into a syringe and added dropwise to a stirred carboxylated nitrile butadiene rubber (XNBR) emulsion. The concentration of the carboxylated nitrile butadiene rubber emulsion is 15 wt%. Before addition, the pH of the emulsion is adjusted to 7.0 by adding ammonia, and the mixture is stirred at approximately 500 rpm at room temperature. In this embodiment, the dripping rate is controlled at 1 drop / second, and the droplet diameter is controlled by the injection needle (a 0.5–2 mm inner diameter needle can be selected to obtain capsules of different sizes). When the slurry droplets enter the XNBR emulsion, they rapidly undergo electrostatic recombination with the polymers in the emulsion: the –NH3 carried by the chitosan molecules... + Positive charge and –COO on the surface of XNBR latex particles - Negative charges attract and neutralize each other, forming a dense colloidal composite shell in situ on the droplet surface. Controlling the ambient pH is crucial in this process. On one hand, the pKa of the carboxyl groups (–COOH) in XNBR is approximately 4.2–4.5; under pH 8 conditions, most carboxyl groups undergo deprotonation to become –COO. - With an ionization degree α close to 100%, sufficient negative charge is provided. On the other hand, when chitosan within the droplet encounters an alkaline emulsion environment, the local pH increases. If the pH is too high, chitosan will lose protons and its positive charge. Therefore, it is necessary to maintain the pH at the interface within a moderate range (4-7). According to the Henderson-Hasselbalch equation describing the protonation of basic groups, when the interfacial pH is close to the pKa value of chitosan (e.g., pH≈6.3), approximately 50% of the –NH3 groups will be protonated. + Maintaining protonation is crucial; if the local pH rises above 7, the degree of protonation will drop to less than 10%, which is detrimental to the formation of the composite shell. By controlling the droplet infusion rate and the emulsion's buffering capacity, the pH of the droplet surface is maintained within a reasonable range, thus ensuring the smooth formation of a complete gel shell. Conversely, if the ambient pH is too low (e.g., pKa≈4), the ionization degree of the XNBR carboxyl groups decreases sharply (at pH=3, –COO…). - If the proportion is less than 10%, it cannot provide enough anionic groups, which also leads to the shell not forming or being weak.

[0037] 4. Maturation and Collection: Add the slurry dropwise to the emulsion and continue stirring for approximately 30 minutes to allow the shell layer to fully grow and solidify. Formed capsules can be obtained in a relatively short time. In this embodiment, to ensure shell integrity, after stirring for 30 minutes, the mixture was allowed to stand for a short while to observe that the resulting capsules had a uniform surface and no obvious fragments falling off. Subsequently, stirring was stopped, and the capsules were separated and collected from the emulsion using a filter or centrifugation.

[0038] 5. Freeze-drying molding: The wet capsules are rapidly placed in a low-temperature environment (such as liquid nitrogen or a -80°C freezer) to freeze them, causing the internal moisture to solidify. They are then dried in a vacuum freeze dryer, where sublimation removes the ice crystals and water, resulting in a dried aerogel capsule product. During freeze-drying, the chitosan gel and aerogel framework inside the capsule solidify and form a stable porous structure. The outer polyelectrolyte shell also gradually shrinks and adheres to the core surface as the moisture is removed. The resulting capsules are approximately spherical, with a size of about 3–5 mm (depending on the droplet size), and are lightweight.

[0039] Result: The density of the capsules prepared in this example was 80 mg / cm³. 3 The capsule exhibits a distinct core-shell structure. When placed on the dandelion seed villi, the seeds do not sink or deform, indicating that the capsule has an extremely low density. Figure 1 As shown, scanning electron microscopy revealed a cross-section of the capsule, exhibiting a porous network at the center (a framework formed by chitosan and aerogel particles), covered by a thin, dense shell membrane of 5 μm thickness, tightly bonded to the core, with no interfacial delamination observed. This demonstrates that the aerogel capsule with the desired core-shell structure was successfully prepared using this method.

[0040] Example 2

[0041] A method for preparing a heat-processable adhesive aerogel capsule, comprising the following steps:

[0042] 1. Preparation of Chitosan Solution (CTS): Chitosan was dissolved in a dilute deionized aqueous solution of acetic acid to prepare a 6 wt% acidic chitosan solution. The pH of this acidic chitosan solution was 5.

[0043] 2. Preparation of chitosan / aerogel slurry: Hydrophobic silica aerogel powder is added to the above chitosan solution while stirring slowly to fully wet and disperse the aerogel particles in the chitosan solution, forming a uniform slurry. In this embodiment, 0.15g of aerogel powder is added to 20g of chitosan solution;

[0044] 3. Emulsion self-assembly into a shell: The prepared CTS / aerogel slurry is loaded into a syringe and added dropwise to the stirred carboxylated styrene-butadiene rubber latex. The concentration of the carboxylated styrene-butadiene rubber latex is 70 wt%. Before addition, the pH of the latex is adjusted to 6.0 by adding ammonia, and the mixture is stirred at approximately 500 rpm at room temperature. In this embodiment, the dripping rate is controlled at 1 drop / second.

[0045] 4. Maturation and Collection: Drop the slurry solution into the emulsion and continue stirring for about 2 minutes to allow the shell to grow and solidify fully;

[0046] 5. Freeze-drying molding: The wet capsules are rapidly placed in a low temperature (such as liquid nitrogen or a -80°C freezer) to freeze them, causing the internal moisture to solidify. Then, they are dried in a vacuum freeze dryer, and the ice crystals are removed by sublimation to obtain the dried aerogel capsule product. The density of the aerogel capsules was tested to be 50 mg / cm³. 3 The shell thickness is 2 μm.

[0047] Example 3

[0048] A method for preparing a heat-processable adhesive aerogel capsule, comprising the following steps:

[0049] 1. Preparation of Chitosan Solution (CTS): Chitosan was dissolved in a dilute deionized aqueous solution of acetic acid to prepare an 8 wt% acidic chitosan solution. The pH of this acidic chitosan solution was 4.

[0050] 2. Preparation of chitosan / aerogel slurry: Hydrophobic silica aerogel powder is added to the above chitosan solution while stirring slowly to fully wet and disperse the aerogel particles in the chitosan solution, forming a uniform slurry. In this embodiment, 0.2g of aerogel powder is added to 20g of chitosan solution;

[0051] 3. Emulsion self-assembly into a shell: The prepared CTS / aerogel slurry is loaded into a syringe and added dropwise to the stirred hydrogenated carboxylated styrene-butadiene rubber latex. The concentration of the hydrogenated carboxylated styrene-butadiene rubber latex is 35 wt%. Before addition, the pH of the latex is adjusted to 5.0 by adding ammonia, and the mixture is stirred at approximately 500 rpm at room temperature. In this embodiment, the dripping rate is controlled at 1 drop / second.

[0052] 4. Maturation and Collection: Drop the slurry solution into the emulsion and continue stirring for about 10 minutes to allow the shell to grow and solidify fully;

[0053] 5. Freeze-drying molding: The wet capsules are rapidly placed in a low temperature (such as liquid nitrogen or a -80°C freezer) to freeze them, causing the internal moisture to solidify. Then, they are dried in a vacuum freeze dryer, and the ice crystals are removed by sublimation to obtain the dried aerogel capsule product. The density of the aerogel capsules was tested to be 73 mg / cm³. 3 The shell thickness is 4 μm.

[0054] Example 4

[0055] A method for preparing a heat-processable adhesive aerogel capsule, comprising the following steps:

[0056] 1. Preparation of Chitosan Solution (CTS): Chitosan was dissolved in a dilute deionized aqueous solution of acetic acid to prepare a 10 wt% acidic chitosan solution. The pH of this acidic chitosan solution was 4.

[0057] 2. Preparation of chitosan / aerogel slurry: Hydrophobic silica aerogel powder is added to the above chitosan solution while stirring slowly to fully wet and disperse the aerogel particles in the chitosan solution, forming a uniform slurry. In this embodiment, 0.3g of aerogel powder is added to 20g of chitosan solution;

[0058] 3. Emulsion self-assembly into a shell: The prepared CTS / aerogel slurry is loaded into a syringe and added dropwise to the stirred carboxylated styrene-butadiene rubber (XNBR) emulsion. The concentration of the carboxylated styrene-butadiene rubber emulsion is 50 wt%. The pH of the emulsion is adjusted to 4.0 by adding ammonia before addition, and the mixture is stirred at approximately 500 rpm at room temperature. In this embodiment, the dripping rate is controlled at 1 drop / second.

[0059] 4. Maturation and Collection: Drop the slurry solution into the emulsion and continue stirring for about 20 minutes to allow the shell to grow and solidify fully;

[0060] 5. Freeze-drying molding: The wet capsules are rapidly placed in a low temperature (such as liquid nitrogen or a -80°C freezer) to freeze them, causing the internal moisture to solidify. Then, they are dried in a vacuum freeze dryer, and the ice crystals are removed by sublimation to obtain the dried aerogel capsule product. The density of the aerogel capsules was tested to be 100 mg / cm³. 3 The shell thickness is 10 μm.

[0061] Comparative Example 1

[0062] The remaining steps and conditions are the same as in Example 1, and will not be repeated here, except that the chitosan solution concentration is 3%. Complete capsules cannot be obtained.

[0063] When the chitosan concentration is below 5%, it cannot form complete capsules after being added to the emulsion, instead producing loose fragments or unstable gel clusters. This is because at low concentrations, the slurry viscosity and chitosan content are insufficient, making it difficult to coat aerogel particles and provide enough polyelectrolytes to form a robust shell.

[0064] Comparative Example 2

[0065] The remaining steps and conditions are the same as in Example 1, and will not be repeated here. The difference is that the slurry is dripped into the natural rubber latex and stirred for another 4 hours. Capsules cannot form because a polyelectrolyte shell cannot be formed.

[0066] Comparative Example 3

[0067] The remaining steps and conditions are the same as in Example 1, and will not be repeated here. The difference is that the initial pH of the XNBR emulsion is adjusted to 9. Due to the strong alkalinity of the environment, chitosan is rapidly deprotonated, the interfacial charge effect is weakened, and a large amount of shell peeling occurs on the surface of the resulting capsules.

[0068] Comparative Example 4

[0069] The remaining steps and conditions are the same as in Example 1, and will not be repeated here. The difference is that the XNBR emulsion concentration is 3 wt%. Complete capsules cannot be obtained.

[0070] Comparative Example 5

[0071] The remaining steps and conditions are the same as in Example 1, and will not be repeated here. The difference is that the rubber latex used is butyl rubber latex, which cannot form capsules.

[0072] Several dried aerogel capsules obtained in Example 1 were taken and their self-adhesive molding ability and adhesion performance to different substrates were tested.

[0073] 1. Self-adhesive 3D molding: such as Figure 3 and Figure 4 As shown, several capsules were filled into a heat-resistant mold of a certain shape and lightly compacted until the filler occupied approximately 70% of the mold volume. The mold was then placed in a constant-temperature oven at 80°C for 1 hour, removed, cooled to room temperature, and demolded to obtain an integrated aerogel capsule block. Tests revealed that this block formed by the thermal fusion of capsules possesses certain mechanical strength and toughness. For example, after two capsules were pressed and bonded together at 80°C, the interfacial shear strength was measured to be on the order of tens of kilopascals. In this embodiment, the density of the capsule block is approximately 0.10 g / cm³. 3 The thermal conductivity is approximately 0.035 W / m. -1 ·K -1 When a weight is suspended from one end of the block and stretched, it is found that the bonding interface between the capsules does not break, but structural failure occurs first within the capsule itself, indicating that the bonding strength at the interface is higher than some mechanical strength parameters of the capsule body.

[0074] 2. Adhesion to heterogeneous surfaces: such as Figure 5As shown, several capsules were laid on substrates of different materials, including wood, stainless steel, glass, polycarbonate, and rubber. Each substrate surface was covered with a single layer of capsules. Nylon mesh was used to fix the capsules to the substrate surface, and then hot air (approximately 70–80°C) was applied for 2–3 minutes to soften the capsule surface and allow it to adhere to the substrate. After cooling, the mesh was removed, revealing that the capsules were firmly adhered to each substrate and bonded together as a single layer. Peel tests were performed on the capsule layers adhered to the substrates. It was found that a stress >50 kPa was required to peel the capsule layers from surfaces such as wood and rubber, while an adhesion strength of approximately 20–30 kPa was observed on smooth surfaces such as glass and stainless steel. Further observation of the capsule-substrate interface using an electron microscope revealed that the capsule shell layer adhered tightly to the rough surface of the substrate, with some of the adhesive penetrating into the micropores or uneven areas of the substrate, achieving mechanical interlocking. Simultaneously, no obvious interfacial voids were observed on any of the different substrates, indicating that the capsule shell could form good wet contact and adhesion to various materials.

[0075] 3. Flame Retardant Performance: Several capsules were self-adhesively bonded to form a heat insulation layer approximately 5mm thick. Simple combustion comparison experiments were conducted with commercially available PE foam, PU foam, and PS foam boards. The bottom of the samples was horizontally ignited with a butane torch flame for 5 seconds, then the flame source was removed, and this process was repeated twice. The results showed that PE, PU, ​​and PS foams all rapidly melted and burned through under the flame, and even after the flame source was removed, residual molten material dripped and continued to burn; before combustion... Figure 6 As shown in (a), the micron-sized polymer electrolyte shell of the capsule of the present invention rapidly forms a flame-retardant carbon layer without any penetrating cracks (as shown in the image). Figure 6 (b) As shown, the flame immediately self-extinguished without continued combustion after being removed. Further microscopic observation revealed that the outer PEC formed a hard carbonized shell less than 1 micrometer thick (as shown in [image]). Figure 6 (c) As shown, this effectively prevents the spread of flame and heat to the inner layer. Therefore, the material of this invention exhibits excellent ablation resistance and flame retardant properties in open flame environments.

[0076] In summary, the aerogel capsule material of the present invention achieves thermally responsive self-adhesion and effective adhesion to various materials while maintaining lightweight and high thermal insulation properties. It also possesses good mechanical strength and flame retardant properties, verifying its feasibility and superiority as a thermal insulation adhesive material.

[0077] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A heat-processable adhesive aerogel capsule, characterized in that, It includes a porous insulating core and a gel-like shell covering the core; the core comprises a porous network structure formed by silicon-based aerogel and chitosan composite; the shell is composed of a polyelectrolyte composite formed by chitosan and carboxylated rubber latex through electrostatic interaction, and is tightly attached to the surface of the core.

2. The heat-processable adhesive aerogel capsule according to claim 1, characterized in that, The carboxylated rubber latex includes one or more of carboxylated nitrile butadiene rubber latex, carboxylated styrene-butadiene rubber latex, and hydrogenated carboxylated nitrile butadiene rubber latex.

3. The heat-processable adhesive aerogel capsule according to claim 1, characterized in that, The capsule is spherical or nearly spherical in shape and has a density of 50–100 mg / cm³. 3 The shell thickness is 2–10 μm.

4. The heat-processable adhesive aerogel capsule according to claim 1, characterized in that, Multiple capsules can adhere to each other to form an integral structure at a temperature of ≤80°C.

5. The heat-processable adhesive aerogel capsule according to claim 1, characterized in that, The capsule shell is formed by the self-assembly of protonated chitosan cations and deprotonated carboxylated rubber latex anions under pH 4–7 conditions.

6. A method for preparing a heat-processable adhesive aerogel capsule as described in any one of claims 1-5, characterized in that, Includes the following steps: a. Chitosan is dissolved in an acidic aqueous solution to prepare a chitosan solution, which is then mixed with silica aerogel powder to form a homogeneous slurry; b. Add the slurry droplets to the stirred carboxylated rubber latex to form a chitosan-carboxylated rubber latex polyelectrolyte composite shell on the droplet surface, thus obtaining a wet capsule; c. Freeze-dry the obtained wet capsules to remove moisture, and obtain the aerogel capsules; In step a, the concentration of the chitosan solution is 5–10 wt%; In step b, the concentration of the carboxylated rubber emulsion is 15-70 wt%, the pH value of the carboxylated rubber emulsion is adjusted to 4-7, and the stirring time is 2-60 minutes.

7. The method for preparing the heat-processable adhesive aerogel capsule according to claim 6, characterized in that, In step b, the slurry dripping speed is controlled at 1 drop / second, and multiple points are injected simultaneously during the dripping process to improve preparation efficiency.

8. The application of a heat-processable adhesive aerogel capsule as described in any one of claims 1-5 in the fields of heat insulation, heat preservation, fireproofing, and cushioning protection.

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