Four-side elastic aerogel thermal insulation material and preparation method thereof

Abstract

The invention relates to the technical field of aerogel materials, in particular to a four-side elastic aerogel thermal insulation material and a preparation method thereof. The invention relates to a four-side elastic aerogel thermal insulation material, which comprises the following substances by weight: 20-30 parts of TPU resin; and 0.5 to 2.0 parts of ethyl silicate. According to the preparation method, TPU resin and ethyl silicate are preferably selected as main materials, TPU is taken as a spinning aid, ethyl silicate is taken as a silicon source, different proportions of ethyl silicate are added in the TPU drying process, the TPU enters a screw rod for melt spinning after being dried, and the porous thin film material is prepared by adopting rotor spinning. And soaking the film in absolute ethyl alcohol, adding a catalyst to prepare gel, and performing super-hydrophobic and nitrogen dioxide supercritical drying to prepare the elastic aerogel film. The elastic aerogel thermal insulation material prepared by the method disclosed by the invention has high transverse and longitudinal elasticity and air permeability, does not drop powder and has good thermal insulation performance.

Description

Technical Field

[0001] The invention relates to the technical field of aerogel materials, and in particular to a four-sided elastic aerogel thermal insulation material and a preparation method thereof. Background Art

[0002] Aerogel is a porous material with a three-dimensional nanostructure composed of nanoparticles or polymer molecular chains. It has structural characteristics such as low density, high porosity, high pore volume and high specific surface area. It is the world's smallest known nanoporous solid material with excellent thermal insulation properties and is widely used in aerospace, national defense, petrochemical, energy-saving buildings and many other fields. However, while the unique structure gives aerogel excellent performance, it also brings mechanical performance problems such as low strength, high brittleness and "powder and slag falling off", which makes it impossible to be used in clothing and other fields.

[0003] In order to overcome the problem of aerogel powder shedding, different patents have done a lot of work from different technical approaches. CN118083993B is a highly elastic, non-powdering aerogel composite material and its preparation method, which uses a combination of one or more of amorphous fibers such as basalt microfiber cotton felt, glass fiber, high silica fiber, quartz fiber and zirconium oxide fiber to make non-woven flakes, and then treats these materials with high temperature and strong acid. The aerogel felt prepared from this short fiber non-woven material has no lateral and longitudinal elasticity, only a certain compression elasticity, and it is very small. CN118063842 A, a method for preparing a highly elastic organosilicon aerogel, invented a method for preparing a highly elastic organosilicon aerogel, the specific steps are: first, add an elastic silica precursor, a curing agent, and an emulsifier to a non-polar solvent respectively and mix them evenly, then pour the solution into molds of different structures, hydrolyze and polycondense with ionized water, and then dehydrate at high temperature to form a solid aerogel material. This material requires different materials to be prepared according to the shape of the mold. It only has compression elasticity and lacks lateral elasticity on all four sides, so it cannot be used in the clothing field.

[0004] With respect to the above-mentioned related technologies, the inventors found that although the existing aerogel composite materials meet the strength requirements, they have poor elasticity and cannot be effectively compounded with other clothing and apparel fabrics. When they are actually used as clothing fabrics, the scope of use of aerogel clothing materials is restricted. Summary of the invention

[0005] In order to improve the above technical problems, the present application provides a four-sided elastic aerogel thermal insulation material and a preparation method thereof.

[0006] A four-sided elastic aerogel thermal insulation material adopts the following technical solution: A four-sided elastic aerogel thermal insulation material, comprising the following materials in parts by weight: 20-30 parts of TPU resin; Ethyl silicate 0.5-2.0 parts.

[0007] Through the above technical solution, the present application preferably uses TPU resin and ethyl silicate as the main materials. TPU resin is used as the base material, which gives the material good elasticity and durability, and can effectively restore its original shape when subjected to force, ensuring the stability and durability of the material during use. Aerogel with ethyl silicate as the silicon source can not only improve the thermal insulation of the material, but also enhance its waterproof performance and achieve better warmth retention. The design of this composite aerogel material makes it elastic on all sides, able to adapt to different shapes and movements, and provide a comfortable wearing experience.

[0008] Furthermore, a method for preparing a four-sided elastic aerogel thermal insulation material comprises the following preparation steps: S1, drying and mixing: drying the TPU resin in a dryer, adding a certain proportion of ethyl silicate after drying, stirring and mixing, and collecting the mixture; S2, film formation: placing the mixture in a spinning device, melt extruding and air-spinning to form a film, and collecting a porous film; S3, gel treatment: taking the porous film and placing it in anhydrous ethanol, adding a catalyst and performing gel treatment to prepare a gel material; S4, hydrophobic drying: the gel material is subjected to super-hydrophobic treatment and then to supercritical carbon dioxide drying treatment to prepare the elastic aerogel thermal insulation material.

[0009] Through the above technical scheme, the present application first removes the moisture in the TPU resin by drying treatment to ensure its performance stability in subsequent processing. Subsequently, the mixture is melt-extruded and air-spun into a film to form a porous film. This process can effectively improve the air permeability and transverse and longitudinal elasticity of the material. Next, the gel treatment step causes the silicon source material to form a gel structure by immersing the porous film in anhydrous ethanol and adding a catalyst. This stage is crucial to the final performance of the material and ensures that it has good thermal insulation properties. Finally, the superhydrophobic drying treatment ensures that the material has excellent waterproof properties after completion, making it suitable for various environmental conditions. Overall, this method not only simplifies the production process, but also ensures the stability and reliability of material performance.

[0010] Furthermore, the drying treatment in step S1 is performed at a drying temperature of 90° C.-110° C. and for 2-4 hours.

[0011] Furthermore, the present application optimizes the temperature range of the drying process, within which the moisture in the TPU resin can be effectively removed without negatively affecting its thermal stability. Too low a temperature may result in incomplete removal of moisture, thereby affecting the performance of the material in the subsequent manufacturing process; while too high a temperature may cause degradation or performance degradation of the TPU resin. By optimizing the drying temperature, not only the production efficiency is improved, but also the processing performance of the material in the subsequent steps and the quality of the final product are guaranteed.

[0012] Furthermore, the melt extrusion temperature in step S2 is 190-210°C.

[0013] Through the above technical solution, the present application optimizes the temperature of melt extrusion to ensure that the TPU resin can fully melt and flow during the extrusion molding process, thereby forming a uniform film. This temperature range can also maintain the stability of ethyl silicate and prevent it from decomposing or losing its performance at high temperatures. In addition, the appropriate melt extrusion temperature will have a positive impact on the physical properties of the film, such as thickness, density and pore structure, and help enhance the mechanical properties and thermal insulation properties of the final material.

[0014] Furthermore, the catalyst in step S3 is 0.1-0.3% by mass of ammonia water.

[0015] Through the above technical scheme, the present application uses 0.1-0.3% ammonia water as a catalyst in the gel treatment process in order to improve the rate and effect of the reaction. Ammonia water as a catalyst can effectively promote the polymerization reaction of ethyl silicate, so that it quickly forms a gel structure, thereby improving the strength and stability of the material. The advantage of using ammonia water is that it is low in cost and easy to obtain, and no complex chemical components are introduced during the gelation process, ensuring the environmental protection and safety of the material. In addition, the appropriate catalyst concentration can also avoid too fast or too slow reaction, ensuring the uniformity and consistency of the gel treatment.

[0016] Furthermore, the gel treatment time in step S3 is 3-4 hours.

[0017] Through the above technical solution, the present application sets a treatment time of 3-4 hours in the gel treatment step, which can ensure that ethyl silicate fully reacts with the catalyst. This time range is moderate, which can not only avoid the waste of resources caused by too long reaction time, but also ensure that the gelation effect of the material reaches the best state. Appropriate gel treatment time helps to form a good three-dimensional network structure and improve the mechanical properties and thermal insulation properties of the material, which is particularly important for the final application of aerogel materials such as thermal insulation products.

[0018] Furthermore, the modifier used in the super-hydrophobic treatment in step S4 includes any one of azane or silane.

[0019] Through the above technical solution, the present application uses azane or silane as a modifier in the super-hydrophobic treatment step, which can effectively improve the hydrophobicity of the material. These modifiers reduce the adhesion of water molecules by forming a protective film on the surface of the material, thereby enhancing the waterproofness and durability of the material. The super-hydrophobic property is particularly important for aerogel structures because it can prevent the penetration of water and prevent the collapse of the aerogel structure.

[0020] Furthermore, the amount of the modifier added is 1% of the mass of the solvent, the solvent is ethanol, and the superhydrophobic treatment time is 3-7 hours.

[0021] Through the above technical scheme, the application sets the amount of modifier added to 1% of the solvent mass, and the super-hydrophobic treatment time is 3-7h. This parameter setting ensures that the modifier can effectively combine with the material surface to form a persistent hydrophobicity. The optimized addition amount and treatment time not only improve the modification efficiency, but also avoid the waste of resources caused by excessive use of modifiers. Appropriate treatment time can ensure the uniform distribution of the modifier, thereby ensuring the stability and reliability of the final material in different environments. Good super-hydrophobicity makes the material more suitable for a variety of warm-keeping application scenarios, enhancing the practical value and market competitiveness of the material.

[0022] In summary, this application has the following beneficial effects: First, the present application prefers TPU resin and ethyl silicate as the main materials. TPU resin as the base material gives the material good elasticity and durability, and can effectively restore its original shape when subjected to force, ensuring the stability and durability of the material during use. Aerogel with ethyl silicate as the silicon source can not only improve the thermal insulation of the material, but also enhance its waterproof performance and achieve better warmth retention. The design of this composite aerogel material makes it elastic on all sides, able to adapt to different shapes and movements, and provide a comfortable wearing experience.

[0023] Second, the present application first removes moisture from the TPU resin through a drying process to ensure its performance stability in subsequent processing. Subsequently, the mixture is melt-extruded and air-spun into a film to form a porous film. This process can effectively improve the air permeability and lightweight properties of the material. Next, the gel treatment step causes the material to form a gel structure by immersing the porous film in anhydrous ethanol and adding a catalyst. This stage is crucial to the final performance of the material, ensuring that it has good elasticity and warmth retention. Finally, the superhydrophobic drying process ensures that the material has excellent waterproof properties after completion, making it suitable for various environmental conditions. Overall, this method not only simplifies the production process, but also ensures the stability and reliability of material performance.

[0024] Third, the present application uses 0.1-0.3% ammonia water as a catalyst during the gel treatment process in order to increase the rate and effect of the reaction. Ammonia water as a catalyst can effectively promote the polymerization reaction of ethyl silicate, so that it quickly forms a gel structure, thereby improving the strength and stability of the material. The advantage of using ammonia water is that it is low in cost and easy to obtain. At the same time, no complex chemical components are introduced during the gelation process, ensuring the environmental protection and safety of the material. In addition, the appropriate catalyst concentration can also avoid too fast or too slow reaction, ensuring the uniformity and consistency of the gel treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a 3000x SEM picture of the elastic aerogel thermal insulation material prepared in Example 1 of the present invention; Figure 2 This is a 10,000-fold SEM image of the elastic aerogel thermal insulation material prepared in Example 1 of the present invention; Figure 3 This is a surface scan of the elastic aerogel thermal insulation material prepared in Example 1 of the present invention using an energy spectrometer, where the red dots are the imaging points of Si. DETAILED DESCRIPTION

[0026] The present application is further described in detail below with reference to the embodiments.

[0027] In the examples of the present application, the raw materials and instruments used are as follows, but not limited thereto: The present application is further described in detail below with reference to the embodiments.

[0028] Example 1 A method for preparing a four-sided elastic aerogel thermal insulation material, comprising the following preparation steps: S1. Mixing: Take 200 kg of TPU resin chips with a melt mass flow rate MFR of 60-120 g / 10 min and place them in a stirring dryer at a drying temperature of 90° C. for drying for 2.5 h, collect the dried particles and stir and mix them with 5 kg of ethyl silicate for 30 min, and collect the mixture; S2. Film formation: Place the mixture in a spinning device, control the temperatures of the feeding section, melting section and metering section of the screw at 190°C, 195°C and 210°C respectively, melt extrude and air-spin to form a film, and control the film weight to be 60g / m 2 , the porous film is collected; S3, gel treatment: take the porous film and place it in anhydrous ethanol, add 0.1% by mass of ammonia water and perform gel treatment to prepare a gel material; S4, hydrophobic drying: the gel material is immersed in a 5% by mass hexamethyldisilazane / ethanol mixed solution for super-hydrophobic treatment, and then subjected to supercritical carbon dioxide drying treatment to prepare the elastic aerogel thermal insulation material.

[0029] Example 2 A method for preparing a four-sided elastic aerogel thermal insulation material, comprising the following preparation steps: S1. Mixing: 250 kg of TPU resin chips with a melt mass flow rate (MFR) of 60-120 g / 10 min are placed in a stirring dryer at a drying temperature of 90° C. for drying for 2.5 h, and the dried particles are collected and stirred and mixed with 15 kg of ethyl silicate for 30 min to obtain a mixture; S2. Film formation: Place the mixture in a spinning device, control the temperatures of the feeding section, melting section and metering section of the screw at 195°C, 200°C and 210°C respectively, melt extrude and air-spin to form a film, and control the film weight to be 75g / m 2 , the porous film is collected; S3, gel treatment: taking the porous film and placing it in anhydrous ethanol, adding 0.2% by mass of ammonia water and performing gel treatment to prepare a gel material; S4, hydrophobic drying: the gel material is immersed in a 5% by mass methyltrimethoxysilane / ethanol mixed solution for super hydrophobic treatment, and then subjected to supercritical carbon dioxide drying treatment to prepare the elastic aerogel thermal insulation material.

[0030] Example 3 A method for preparing a four-sided elastic aerogel thermal insulation material, comprising the following preparation steps: S1. Mixing: 300 kg of TPU resin chips with a melt mass flow rate (MFR) of 60-120 g / 10 min are placed in a stirring dryer at a drying temperature of 90° C. for drying for 2.5 h, and the dried particles are collected and stirred and mixed with 20 kg of ethyl silicate for 30 min to obtain a mixture; S2. Film formation: Place the mixture in a spinning device, control the temperatures of the feeding section, melting section and metering section of the screw at 195°C, 200°C and 210°C respectively, melt extrude and air-spin to form a film, and control the film weight to be 80g / m 2 , the porous film is collected; S3, gel treatment: taking the porous film and placing it in anhydrous ethanol, adding 0.1-0.3% by mass of ammonia water and performing gel treatment to prepare a gel material; S4, hydrophobic drying: the gel material is immersed in a 5% by mass methyltrimethoxysilane / ethanol mixed solution for super hydrophobic treatment, and then subjected to supercritical carbon dioxide drying treatment to prepare the elastic aerogel thermal insulation material.

[0031] Performance Testing The elastic aerogel thermal insulation materials prepared in Examples 1-3 were subjected to performance testing, specifically testing their thermal conductivity and mechanical properties: Thermal conductivity: Tested according to GB / T 10295-2008 standard; Mechanical properties: tested according to GB / T 1040.3-2006 standard The details are shown in Table 1 below: Table 1 Performance test table project Thermal conductivity W / (mK) Transverse elastic elongation% Longitudinal elastic elongation% Example 1 0.018 >50 >40 Example 2 0.016 >55 >45 Example 3 0.015 >60 >50 From the above embodiments 1-3, Figure 1-3 From the results in Table 1, we can find that: The present application preferably uses TPU resin and ethyl silicate as the main materials. TPU resin as the base material gives the material good elasticity and durability, and can effectively restore its original shape when subjected to force, ensuring the stability and durability of the material during use. Aerogel with ethyl silicate as the silicon source can not only improve the thermal insulation of the material, but also enhance its waterproof performance and achieve better warmth retention. The design of this composite aerogel material makes it elastic on all sides, able to adapt to different shapes and movements, and provide a comfortable wearing experience.

[0032] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

[0033] All publications, patent applications, patents and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings conventionally understood by those skilled in the art. In the event of a conflict, the definition in this specification shall prevail.

[0034] When this specification uses the prefix "well-known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, etc., the objects introduced by the prefix cover those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become recognized in the art as being suitable for similar purposes.

[0035] In the context of the present specification, any matters or items not mentioned are directly applicable to those known in the art without any changes except those explicitly stated.

Claims

1. A four-sided elastic aerogel thermal insulation material, characterized in that: The composition includes the following materials in parts by weight: 20-30 parts of TPU resin; Ethyl silicate 0.5-2.0 parts.

2. The method for preparing a four-sided elastic aerogel thermal insulation material according to claim 1, characterized in that: The method comprises the following preparation steps: S1, drying and mixing: drying the TPU resin in a dryer, adding a certain proportion of ethyl silicate after drying, stirring and mixing, and collecting the mixture; S2, film formation: placing the mixture in a spinning device, melt extruding and air-spinning to form a film, and collecting a porous film; S3, gel treatment: taking the porous film and placing it in anhydrous ethanol, adding a catalyst and performing gel treatment to prepare a gel material; S4, hydrophobic drying: the gel material is subjected to super-hydrophobic treatment and then to supercritical carbon dioxide drying treatment to prepare the elastic aerogel thermal insulation material.

3. The method for preparing a four-sided elastic aerogel thermal insulation material according to claim 2, characterized in that: The parameters of the drying process described in step S1 are a drying temperature of 90° C.-110° C. and a drying time of 2-4 hours.

4. The method for preparing a four-sided elastic aerogel thermal insulation material according to claim 2, characterized in that: The melt extrusion temperature in step S2 is 190-210°C.

5. The method for preparing a four-sided elastic aerogel thermal insulation material according to claim 2, characterized in that: The catalyst in step S3 is 0.1-0.3% ammonia water by mass.

6. The method for preparing a four-sided elastic aerogel thermal insulation material according to claim 2, characterized in that: The gel treatment time in step S3 is 3-4 hours.

7. The method for preparing a four-sided elastic aerogel thermal insulation material according to claim 2, characterized in that: The modifier used in the super-hydrophobic treatment in step S4 includes any one of azane or silane.

8. The method for preparing a four-sided elastic aerogel thermal insulation material according to claim 7, characterized in that: The amount of the modifier added is 1% of the mass of the solvent, the solvent is ethanol, and the superhydrophobic treatment time is 3-7 hours.

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