WO2023128929A1

WO2023128929A1 - Multi-component aerogel and method for producing the same

Info

Publication number: WO2023128929A1
Application number: PCT/TR2022/050341
Authority: WO
Inventors: Cem ÜNSAL; Yaşar Dilek KUT; Zeynep BAŞYİĞİT ÖMEROĞULLARI; Cengiz KARABULUT
Original assignee: Formfleks Otomoti̇v Yan Sanayi̇ Ve Ti̇caret Anoni̇m Şi̇rketi̇
Priority date: 2021-12-28
Filing date: 2022-04-15
Publication date: 2023-07-06

Abstract

The invention relates to a multi-component aerogel for use in all fields that require high thermal and acoustic insulation, particularly automotive, aircraft, aerospace, defense and construction industries and a method for producing same. Unlike the prior art applications, the object of the invention is to synthesize sol solution in a single bath instead of separately synthesizing and combining each sol solution.

Description

MULTI-COMPONENT AEROGEL AND METHOD FOR PRODUCING THE SAME

Field of the Invention

The present invention relates to a multi-component aerogel for use in all fields that require high thermal and acoustic insulation, particularly automotive, aircraft, aerospace, defense and construction industries and a method for producing the same.

State of the Art

Some conventional materials with low thermal conductivity such as mineral wool, expanded polystyrene (EPS), extruded polystyrene (XPS), polyurethane (PUR) and cellulose structures are widely used to provide thermal and acoustic insulation. Of these materials, mineral wool is a fluffy short fiber made of natural mineral raw materials, which covers glass wool and rock wool and is normally produced as blankets, mats, ropes and sheets. Good acoustic performance and low density can be listed among some of the major advantages of mineral wool, while sensitivity to moisture and the fact that the material can degrade by 10% even under very low moisture conditions can lead to reduction in thermal and acoustic properties of mineral wool.

Expanded polystyrene, commonly known as EPS, is a lightweight material in rigid form, produced as a foam by styrene monomer polymerization. EPS is a cellular rigid plastic with a blowing agent and air trapped within its cells. EPS is commonly used as a protective packaging material, as an insulation material in the outer or inner wall, and also an acoustic insulation material, impact resistance low thermal conductivity of 30 - 40 mW/(m.K) at 10 <0, high compression strength, moist ure resistance and a low density of 40 kg/m³ can be listed among the superior properties of EPS. The thermal conductivity of EPS varies with temperature, moisture and mass density. The greatest drawback of EPS is that its foam is combustible. For this reason, it needs to be coated with a flame retardant chemical known as hexabromocyclododecane (HBCD). Recently, the use of HCBD has become the topic of intensive discussions due to the health and environmental risks associated with its use. Polyurethane foam is typically formed by a chemical reaction between isocyanates and polyols (alcohols containing multiple hydroxyl groups) (2). During the blowing process, closed pores are filled with gases such as HFC, CO2 or C6H12. It is used in building insulation materials including surface coatings, adhesives and rigid plastics. PUR has a typical thermal conductivity value of 20-30 mW/(m.K), which is considered to be lower than mineral wool, polystyrene and cellulosic thermal insulation material. Although polyurethane foam is considered a safe material for its intended use, it is also reported that it can cause serious health problems and fire hazards.

Cellulose is an organic compound produced from recycled paper or wood pulp. Cellulose products are used in interior and exterior walls of buildings to provide thermal insulation, and in wall and ceiling cavities to provide acoustic insulation. It has good acoustic insulation, flame retardancy, vapor barrier and good thermal performance. Conventional cellulose products have a density of 24- 27.2 kg/m³ and a thermal conductivity of 35 mW/(m.K) at 10 mA. In addition, cellulose is a completely green and recyclable insulation material to protect the environment. Every year, approximately eight million tons of CO2 emission can be obtained by recycling used papers into cellulose insulation. The biggest drawback of the material is its high flammability (1 ).

It is inevitable that aerogels, which are very suitable for use as thermal and sound insulation materials due to their properties such as high specific surface area, high porosity, low density, low dielectric constant, excellent sound and thermal insulation and nano-porous lightweight structures, will replace conventional materials. For commercial products, the thermal conductivity value drops down to 13 mW/(m.K) (2). In addition to the listed properties, values such as elastic modulus, compressive strength, shear strength are also important for the functional use of aerogel materials in industry. Therefore, the properties of aerogels also need to be improved. Various studies are carried out to examine the properties of aerogels and to develop new aerogel types with the required properties, and performance comparisons are made with conventionally used materials. There are aerogel studies on the use of different precursors (3, 4), the production of aerogel-reinforced composites (5, 6), new types of aerogels apart from silica (7) and aerogels modified by adding certain chemicals (8).

Monolithic aerogel, aerogel-reinforced composite materials and aerogel materials with improved properties by chemical materials do not deliver satisfactory industrial performance in terms of thermal and acoustic insulation, mechanical strength and economic viability.

One of the important features of silica aerogels is that they have very low thermal conductivity, typically at a level of 0.015 W.nr¹.K’¹ at ambient temperature, ambient pressure and relative humidity. These values are significantly lower than the conductivity of air under the same conditions (e.g. 0.025 W.nr¹.K’¹). For this reason, silica aerogels are among the best-known thermal insulation materials. The acoustic properties of silica aerogels are closely related to their thermal insulation properties. Acoustic propagation in aerogels depends on the nature and pressure of the intermediate gas, the density of the aerogel and the texture to a larger extent. Silica aerogels are indeed excellent acoustic insulators. The compressive strength, tensile strength, and elastic modulus of silica aerogels are very low and largely dependent on mesh connectivity and aerogel density (9).

In a study on the production of silica aerogel, it was observed that the thermal conductivity at room temperature was 0.0215 W/(mK) and the initial degradation temperature was 51 1 <0. It was stated that an aerogel with a thickness of 1 1 .8 mm and a density of 60 mg/cm³ exhibited good sound absorption and acoustic insulation properties. In the study, when the sound frequency was 2000 Hz, the sound absorption coefficient was 0.91 and the sound transmission loss between 500 and 1600 Hz was measured as 13 - 21 dB. In polyimide aerogel studies performed with monolithic thermal and acoustic insulation, the thermal conductivity is at a range of 0.030 W.nr¹.K’¹ and 0.050 0.050 W.m’¹.K’¹, with lower thermal stability than polyurethane foam (10, 11 ). Moreover, the presence of water in the reaction medium during polyimide synthesis can dramatically affect the molecular weight of polyamic acid (12). The water released by spontaneous imidation in the solution medium can also make negative impacts on the molecular weight of polyamic acid (13).

Mechanical strength and thermal insulation performance improvement can be seen in studies where polyurethane is synthesized with silica aerogel composite material. However, the thermal conductivity value does not drop below 0.030 W.nr¹K’¹. It is also observed that mechanical strength and thermal conductivity values are negatively affected when the silica ratio is increased (14, 15).

The study on layered double hydroxide/graphene oxide synergistically enhanced polyimide aerogels for thermal insulation and fire-retardancy is another example of reinforced polyimide aerogels. Here, layered double hydroxide (LDH) - graphene oxide (GO) synergistically enhanced polyimide (PI) aerogels with great thermal insulation, good thermal stability and excellent flame retardancy have been synthesized. The study resulted in a low thermal conductivity value (36 ± 1 ,7 W.nr¹.K’¹) and high compressive modulus (26 ± 1 ,8 MPa) (16).

The most specific examples on the subject can be listed as Cryogel® Z, Pyrogel® 2250 and Spaceloft® produced by Aspen Aerogels. They were successful in obtaining an aerogel with a value of 13.9 W.m ¹.K’¹. These products are blanket insulation materials (17). They should be assessed in terms of many qualities such as thickness, density of material and flexibility. However, it is observed from aerogel properties in the reviewed literature that the studies in which the desired mechanical strength, acoustic and thermal insulation properties are evaluated together are inadequate and that aerogels have not turned into products that can completely replace traditional materials. However, these studies also show that material properties can be improved with different production methods and chemicals.

In conclusion, the drawbacks explained above and the shortcomings in existing solutions to the problems have necessitated improvement in the related technical field.

Summary of the Invention

The present invention relates to a multi-component aerogel which satisfies the requirements listed above and eliminates all disadvantages while bringing additional benefits to the technical field and the method for producing the same.

The present invention is inspired by the existing conditions and aims to solve the drawbacks explained above.

The main aim of the invention is to synthesize hybrid aerogel by combining organic and inorganic main components that can be used individually in the production of aerogel structure in a single bath chemically and side by side with different material types. Existing polymer foams, monolithic and doped aerogels and aerogel-reinforced composite structures do not fully meet the affordability, physical, chemical and mechanical properties required for industrial use. It is known that with the incorporation of inorganic structures into organic polymer structures, many properties such as mechanical, morphological, thermal and electrical properties improve when compared with organic polymers. Inorganic-organic hybrid materials can be formed by strong covalent, coordinated bonds between them or they can be formed by interactions such as weak van-der-Waals, hydrophilic-hydrophobic balance and hydrogen bonds (18). Another object of the invention is to produce an aerogel material that is advantageous in terms of physical, chemical, mechanical and economic properties compared to its equivalents. The present invention is novel and unique in that no method can be found in academic literature on hybrid studies for production of any hybrid aerogel where all synthesis steps are entirely performed in a single bath.

An embodiment of the present invention is based on the production of a hybrid material formed by silica (silicon dioxide) as inorganic component and the chemicals of organic polymeric polyurethane and polyimide structures and the characterization of these materials. The major technical benefits that make the hybrid aerogel material to be formed with the chemicals of the multiple components to be prepared according to the invention unique are given below:

• Silica has low toxicity, can be easily synthesized in different sizes and morphologies, and has high stability.

• A polymeric material resistant to acids, bases and organic solvents due to the high density of hydrogen bridge bonds of polyurethane and the stability of its physical mesh structure.

• Hydrogen bridge bonds provide high mechanical properties by forming a block-like structure in the hard and soft segments between chains.

• Polyimide polymers have superior thermal-oxidative stability, chemical resistance, excellent mechanical and electrical properties and thermoplastic structure.

• Forming an important class among advanced engineering polymers.

Yet another aim of the invention is to provide a new hybrid aerogel by synthesizing many components in a single bath without any pre-treatment steps. There is a wide array of aerogel compositions used in the technical field. However, the common point of all aerogel compositions is the main aspects in which they are synthesized and processed. Aerogels are typically prepared by a wet chemical synthesis approach. The first steps in the synthesis of aerogels are critically important. Because the sol-gel process is generally used to form a solid phase. The solid phase forms the backbone of aerogel and during the process, all parameters including the concentration and type of reagents and solvents, temperature and pH significantly impact gel formation. For the production of aerogels at the design stage, it is necessary to understand the consequences and effects of each stage (19). Aerogels are produced in several consecutive process steps. The first step is the solution preparation step. In this step, a homogenous solution is prepared by reacting various starting materials with suitable solvents. These steps are generally followed by hydrolysis, polymerization, condensation, gelation, washing and aging (20). After these steps, aerogel formation is enabled by supercritical CO2 drying. Supercritical drying is a step in which the liquid in the substance is converted to gas without surface tension and capillary tension, and is the method used to convert gels into aerogels. The key aspect that distinguishes the present invention, which is realized by following the aerogel formation steps, from other studies is that a new hybrid aerogel is obtained by synthesizing multiple components in a single bath without any pre-treatment steps. Literature review yields hybrid studies where aerogels are incorporated into resins in powder form, transferred to material through coating, etc. methods, and combined after certain preliminary preparation stages. The present invention does not show similarity in terms of monolithic aerogel synthesis and application to a resin in powder form or another material through coating, etc. methods. Moreover, it is not a type of hybrid aerogel that is derived by forming a pre-polymer-like structure in monolithic structure and then combining two different components in a single bath.

The below drawings and the detailed description set out with reference to the accompanying drawings provide for a clearer understanding of the structural and characteristic properties and all benefits of the present invention; therefore, the evaluation needs to take these drawings and the detailed description into account.

Brief Description of the Drawings

Figure 1 is a schematic view of the production process of the multi-component aerogel according to the invention.

List of Reference Numerals 101 Sol solution preparation process step

102 Conversion to hybrid sol solution in a single bath process step

103 Gel formation process step

104 Aging process step

105 Drying process step

106 Multi-component aerogel production process step

Detailed Description of the Invention

In order to facilitate a better understanding of the present invention, this detailed description demonstrates the preferred embodiments of the multi-component aerogel according to the invention and the method for producing the same in a non-limiting manner.

The present invention relates to a multi-component aerogel for use in all fields that require high thermal and acoustic insulation, particularly automotive, aircraft, aerospace, defense and construction industries and a method for producing same.

Experiments conducted as part of the invention are exemplified below to facilitate a better understanding of the method for producing the aerogel according to the invention. These examples are related to studies where silica, polyimide and polyurethane main component chemicals are selected. To this end, the below chemicals are listed as examples in a non-limiting manner only for the purposes of facilitating a better understanding of the subject. The invention can also be achieved by using different chemicals with different process parameters.

Initially, a precursor should be selected according to the main component to be used. For instance, as a precursor to silica main component, TEOS is dissolved in alcohol solution to prepare an alkoxide solution. Generally, the first process step is preparing the precursor to aerogel structure in solvent.

If silicate is selected as the main component, the precursor (preferably TEOS) is dissolved in alcohol in inert environment to prepare the alkoxide solution. As such, the precursor component (tetraorthosilicate) is used as a starter material in preparing the sol solution. If silica is selected as the main component, TEOS and/or TMOS and/or Na2SiOa and/or organosilicone can be used as precursor in the process step of preparing the precursor to the aerogel structure in solvent. The alcohol used in the preparation of the alkoxide solution is preferably methanol which acts as a solvent in dissolving the precursor. Alternatively, methanol, ethanol and similar alcohols can be used.

After the precursor is prepared in the solvent, the preparation step of the sol solution is initiated. pH, temperature, mixing speed, amounts/rates of component used, solvent type and catalyst are important factors in the sol solution preparation process step. These factors will affect the gelation rate and the quality of the finished aerogel product. Depending on the type of gel to be produced, different process steps in the gel formation process work differently at different time scales. In general, a slower sol-gel step gives better results. Accelerating the reactions may cause precipitates to form instead of a gel network, or the gel to become weak or even not to form.

The prepared sol solution is formed according to the selected precursor. If silica is selected as the main component, after the preparation of the alkoxide solution, the first step of the sol solution is completed by performing a two-step acid (HCI) I base (NH4OH) catalyzed hydrolysis-condensation process.

Instead of sol solutions that are prepared separately and combined in the final step in prior art applications, hybrid sol solutions can be prepared in a single bath according to the present invention.

In order to prepare a hybrid sol solution in a single bath, the main component (silica, polyurethane, polyimide and similar) chemicals (TEOS, diisocyanate, polyol, diamine, dianhydride and similar) that will form the multi-component structure should be added respectively to the sol solution derived.

If silica is selected as the main component, organic chemicals dissolved in N-methyl-2 pyrrolidone and other chemicals in liquid form are added to the sol solution in question, in the following order, in order to form the desired polymer chains in the structure:

1 . 4,4-Diphenylmethane diisocyanate

2. Polyethylene oxide

3. Polypropylene oxide

4. 1 ,4-Butanediol

5. Oxydianiline 6. Biphenyltetracarboxylic dianhydride

7. Pyromellitic dianhydride

8. 1 ,3,5-Benzenetricarbonyl chloride

9. Acetic anhydride

10. Pyridine

In cases where one of the main components of polyimide or polyurethane is used as a precursor, N-methyl-2 pyrrolidone, Dimethylacetamide and similar solvents are used as the organic solvent.

The functions of said components (the technical effect they produce) and the components that can be used as alternatives are given in the table below:

In one embodiment of the invention, acid (preferably hydrochloric acid) is used as a catalyst to accelerate the reaction and a base (preferably ammonium hydroxide) is used for the condensation process. N-methyl-2 pyrrolidone is the organic solvent used for dissolving organic solid chemicals.

In another embodiment of the invention, chemical imidization is performed by using carboxylic acid anhydride (Acetic anhydride) as a water-absorbing reagent with tertiary amine (Pyridine) as the catalyst. By this means, gel formation is performed faster without the need for high heat. It is also possible to perform thermal imidization or solution imidization instead of chemical imidization.

In the next process step, the mixture is left to stand and converted into gel form (gelation).

After this process step, in the aging process, the gel is preferably kept in alcohol (preferably methanol) for 3 days. The alcohol solution used in the aging process is preferably replaced every 24 hours. It has been determined that the aging time has an impact on the aerogel properties. Therefore, in a preferred embodiment of the invention, the aging process is carried out in the range of 1 to 14 days. Since the aging process is an important process step for the final product, it is important to observe the impact on the chemical and physical properties of the aerogel by experimenting with different time intervals. It has been determined that the aging period has an impact on the pore structure in particular at certain intervals.

After the aging process, the supercritical drying process is carried out and the multicomponent aerogel synthesis is completed. The supercritical drying time can be determined between 2.5 and 12 hours (preferably 5 hours) depending on the deformation in the material. During this process, the gel to be placed in the supercritical dryer is placed in the separator so that it is completely covered with the aging alcohol. In the supercritical drying process, it is important not to keep the supercritical drying time too long to avoid cracks, ruptures, etc. in the aerogel. In another study, the aerogel was soaked in liquid CO2 for 24 hours before performing the supercritical drying operation. This makes it possible to avoid cracks in the aerogel structure. Moreover, when the supercritical process is completed, CO2 should not be released quickly and abruptly. Otherwise, cracks and ruptures occur in the aerogel structure. Instead of supercritical drying, it is possible to form an aerogel with different drying processes, for example at subcritical temperatures. ln yet another embodiment of the invention, triethoxymethylsilane (MTES) and/or trimethylchlorosilane (TMCS) is added to provide functional properties such as flexibility and water repellency to the multi-component aerogel structure.

Ultimately, unlike the prior art applications, the multi-component structure is converted into an aerogel form by synthesizing sol solution in a single bath instead of separately synthesizing and combining each sol solution.

The aerogel according to the invention comprises tetraethyl orthosilicate preferably in the range of 0.5% to 20% by weight, ammonium hydroxide in the range of 0.2% to 15%, methanol in the range of 1 % to 51 %, hydrochloric acid in the range of 0.005% to 0.5%, 4,4-Diphenylmethane diisocyanate in the range of 0.5% to 10%, polyethylene oxide in the range of 0.2% to 10%, polypropylene oxide in the range of 0.2% to 10%, 1 ,4-Butanediol in the range of 0.2% to 10%, oxydianiline in the range of 0.2% to 10%, Biphenyltetracarboxylic dianhydride in the range of 0.1 % to 10%, pyromellitic dianhydride in the range of 0.05% to 15%, 1 ,3,5-Benzenetricarbonyltrichloride in the range of 0.4% to 10%, acetic anhydride in the range of 0.4% to 10%, pyridine in the range of 0.4% to 10%, and N-methyl-2 Pyrrolidone in the range of 15% to 96.145%.

In a preferred embodiment of the invention, the aerogel comprises tetraethyl orthosilicate preferably in the range of 2% to 12.8% by weight, ammonium hydroxide in the range of 1 % to 6.3%, methanol in the range of 4.1 % to 25.4%, hydrochloric acid in the range of 0.1% to 0.02%, 4,4-Diphenylmethane diisocyanate in the range of 1.7% to 2.9%, polyethylene oxide in the range of 0.8% to 1 .4%, polypropylene oxide in the range of 0.8% to 1 .4%, 1 ,4-Butanediol in the range of 0.8% to 1 .4%, oxydianiline in the range of 0.6% to 1 %, Biphenyltetracarboxylic dianhydride in the range of 1.3% to 2.2%, pyromellitic dianhydride in the range of 0.2% to 0.4%, 1 ,3,5-Benzenetricarbonyltrichloride in the range of 1 .5% to 2.4%, acetic anhydride in the range of 1 .8% to 2.8%, pyridine in the range of 1 .8% to 2.8%, and N-methyl-2 Pyrrolidone in the range of 44.1 % to 74.18%.

In different embodiments of the invention, different main components and hence, alternative solvents and chemicals can be used. For example, if silica is selected as the first main component in the first step of aerogel formation, which is preparing a homogeneous solution, the precursor is dissolved in the TEOS alcohol solution and the alkoxide solution is prepared. If polyurethane is chosen, pre-polymer is prepared by using diisocyanate and polyols as precursors. If polyimide is used, polyamic acid is prepared using dianhydrides and diamine as precursors. In the next stage, the chemicals of the organic and inorganic main components that will form the multi-component structure are incorporated in a single bath, so that hydrolysis, polymerization, condensation, gelation, washing, aging and drying process steps are followed.

In order to solve the existing problems in the technical field and achieve the objectives described above, a method for producing multi-component aerogel for use in all fields that require high thermal and acoustic insulation, particularly automotive, aircraft, aerospace, defense and construction industries, comprising the process steps of:

• preparing the precursor to aerogel structure in solvent;

• preparing a sol solution;

• preparing a hybrid sol solution in a single bath by adding, in order, main component chemicals that will form the multi-component structure into the derived sol solution;

• leaving the solution to a stand and converting it to gel form;

• performing aging operation on said gel for 1 to 14 days;

• performing a drying process after aging to obtain a multi-component aerogel.

What characterizes and distinguishes the method of the invention from the prior art is the process step of preparing a hybrid sol solution in a single bath by adding, in order, main component (silica, polyurethane, polyimide and similar) chemicals (TEOS, diisocyanate, polyol, diamine, dianhydride and similar) that will form the multi-component structure into the derived sol solution. It is possible to derive multi-component aerogel in a single bath by applying all of the above-described process steps.

Reference List

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3- Pisal, Abhijit A., and A. Venkateswara Rao. "Comparative studies on the physical properties of TEOS, TMOS and Na2SiOa based silica aerogels by ambient pressure drying method." Journal of Porous Materials 23.6 (2016): 1547-1556.

4- Li, Xiaohua, et al. "A flexible silica aerogel with good thermal and acoustic insulation prepared via water solvent system." Journal of Sol-Gel Science and Technology 92.3 (2019): 652-661.

5- Ahn, Jae Hyeok, et al. "Enhancement of mechanical and thermal characteristics of polyurethane-based composite with silica aerogel." Materials Science Forum. Vol. 951. Trans Tech Publications Ltd, 2019.

6- Fan, Wei, et al. "Lightweight, strong, and super-thermal insulating polyimide composite aerogels under high temperature." Composites Science and Technology 173 (2019): 47-52.

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8- Yan, Peng, Bin Zhou, and Ai Du. "Synthesis of polyimide cross-linked silica aerogels with good acoustic performance." RSC Advances 4.102 (2014): 58252-58259.

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10- Xi, Shuang, et al. "Influence of diamine rigidity and dianhydride rigidity on the microstructure, thermal and mechanical properties of cross-linked polyimide aerogels." Journal of Porous Materials 28.3 (2021 ): 717-725.

1 1 - Feng, Junzong, et al. "Study on thermal conductivities of aromatic polyimide aerogels." ACS applied materials & interfaces 8.20 (2016): 12992-12996. 12- Bessonov, Mihail L, et al. Polyimides: thermally stable polymers. Springer, 1987.

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Claims

CLAIMS A method for producing multi-component aerogel for use in all fields that require high thermal and acoustic insulation, particularly automotive, aircraft, aerospace, defense and construction industries, characterized by comprising; the process steps of:

• preparing the precursor to aerogel structure in solvent;

• preparing a sol solution;

• leaving the solution to a stand and converting it to gel form;

• performing aging operation on said gel for 1 to 14 days;

• performing a drying process after aging to obtain a multi-component aerogel. A method for producing multi-component aerogel according to Claim 1 , wherein if silica is selected as the main component, TEOS and/or TMOS and/or Na2SiOa and/or organosilicone can be used as precursor in the process step of preparing the precursor to the aerogel structure in solvent. A method for producing multi-component aerogel according to any of the preceding claims, wherein if silica is selected as the main component, methanol and/or ethanol alcohols can be used as solvent in the process step of preparing the precursor to aerogel structure in solvent. A method for producing multi-component aerogel according to any of the preceding claims, wherein triethoxymethylsilane and/or trimethylchlorosilane is added to provide functional properties such as flexibility and water repellency to the aerogel structure. A method for producing multi-component aerogel according to any of the preceding claims, wherein organic chemicals are dissolved in solvent and N- methyl-2 pyrrolidone and/or Dimethylacetamide is used in the process step of preparing a hybrid sol solution in a single bath by adding, in order, main component chemicals that will form the multi-component structure into the derived sol solution. A method for producing multi-component aerogel according to any of the preceding claims, wherein diisocyanate, polyol, chain extender, diamine, dianhydride, cross-linker, tertiary amine and carboxylic acid anhydride is respectively added as main component chemicals in the process step of preparing a hybrid sol solution in a single bath by adding, in order, main component chemicals that will form the multi-component structure into the derived sol solution. A method for producing multi-component aerogel according to any of the preceding claims, wherein chemical imidization is performed by using carboxylic acid anhydride as a water-absorbing reagent with tertiary amine as the catalyst. A method for producing multi-component aerogel according to any of the preceding claims, wherein thermal imidization or solution imidization is performed. A method for producing multi-component aerogel according to any of the preceding claims, wherein the alcohol solution used in the aging operation is replaced every 24 hours for 3 days. A method for producing multi-component aerogel according to any of the preceding claims, wherein methanol and/or ethanol alcohols are used in the aging process step. A method for producing multi-component aerogel according to any of the preceding claims, wherein supercritical drying process is carried out the drying process step. A method for producing multi-component aerogel according to any of the preceding claims, wherein supercritical drying is performed for 2.5 to 12 hours. A method for producing multi-component aerogel according to any of the preceding claims, wherein supercritical drying is performed for 5 hours.