Composite material with high light transmission and ultraviolet and infrared double barrier properties as well as preparation method and application of composite material

Abstract

The invention provides a composite material with high light transmission and ultraviolet and infrared double barrier as well as a preparation method and application of the composite material. The preparation method comprises the following steps: carrying out a first reaction on a first mixed reaction system containing nano indium tin oxide, a PMMA prepolymer and a first catalyst to obtain an indium tin oxide poly [1-(methoxycarbonyl methyl) ethylidene] complex; and carrying out a second reaction on a second mixed reaction system containing the indium tin oxide poly [1-(methoxycarbonyl methyl) ethylidene] complex, bis-2, 2, 6, 6-tetramethylpiperidinol sebacate and a second catalyst to obtain the composite material with high light transmission and ultraviolet and infrared double barrier properties, wherein the second mixed reaction system comprises the indium tin oxide poly [1-(methoxycarbonyl methyl) ethylidene] complex, the bis-2, 2, 6, 6-tetramethylpiperidinol sebacate and the second catalyst. The composite material obtained by the preparation method not only has a good ultraviolet and infrared double-barrier function, but also is relatively high in visible light transmittance, and a formed coating is relatively low in haze.

Description

Technical Field

[0001] This invention belongs to the field of composite material technology, specifically relating to a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, its preparation method, and its application. Background Technology

[0002] Ultraviolet and infrared blocking materials are a class of functional materials that can effectively block or reduce the transmission of ultraviolet and infrared rays. They are often used in various occasions where it is necessary to prevent ultraviolet damage or reduce heat transfer, such as building glass curtain walls, car windows, displays, electronic equipment, military equipment, cultural relic protection, personal protective equipment, and certain specific optical devices.

[0003] Currently, existing barrier materials typically possess either infrared or ultraviolet (UV) blocking capabilities. Materials capable of simultaneously blocking both UV and infrared light with a dual blocking rate exceeding 90% are rarely reported. For example, commonly used infrared absorbers include nano-ATO, nano-LaB6, and nano-WO3. These materials generally lack UV blocking capabilities. Therefore, in applications requiring both UV and infrared blocking, additional UV absorbers are usually added to the coating. However, these infrared absorbers are all powder materials with poor optical properties. Even low addition amounts in coatings result in high haze, severely impacting visible light transmission. Since the barrier performance depends on the amount added, the heat insulation film cannot simultaneously achieve both light transmittance and barrier properties, limiting its application range. Summary of the Invention

[0004] To solve all or part of the above-mentioned technical problems, the present invention provides the following technical solutions:

[0005] One objective of this invention is to provide a method for preparing a composite material with high light transmittance and dual violet-infrared blocking properties, the preparation method comprising:

[0006] S1: The first mixed reaction system containing nano-indium tin oxide, PMMA prepolymer and the first catalyst is subjected to the first reaction to obtain indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex;

[0007] S2: A second reaction is carried out in a second mixed reaction system containing indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex, sebacic acid bis-2,2,6,6-tetramethylpiperidine ester and a second catalyst to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking.

[0008] This invention discovers that complexing nano-sized indium tin oxide (ITO) with PMMA prepolymer under specific conditions can achieve molecular-scale dispersion and transform opaque ITO powder into a deep blue transparent solution. Furthermore, the infrared absorption effect of ITO remains stable during this process, thus solving the problems of poor light transmittance and high haze caused by direct coating of powdered ITO. Further, polymerizing the obtained ITO poly[1-(methoxycarbonylmethyl)ethylene] complex with sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester yields a polymer composite material with both ultraviolet and infrared blocking functions. Moreover, during the polymerization process, the transparency of the product is further improved, transforming from a deep blue solution into a highly transparent blue polymer solution with a visible light transmittance exceeding 70%.

[0009] In some embodiments, the content of nano-indium tin oxide in the first mixed reaction system is 2-5 wt%.

[0010] In some embodiments, the content of the PMMA prepolymer is 15-20 wt%.

[0011] In some embodiments, the reaction temperature of the first mixed reaction system is 65–75°C. Higher reaction temperatures can lead to side reactions, resulting in reduced product purity and decreased light transmittance.

[0012] In some embodiments, both the first and second reactions are carried out under anhydrous conditions. This invention has found that carrying out the reaction under aqueous conditions leads to a decrease in the visible light transmittance and violet-infrared blocking rate of the product, possibly because the presence of moisture affects the reaction process and results in a decrease in product purity.

[0013] In some embodiments, the number-average molecular weight of the PMMA prepolymer is 10,000-100,000.

[0014] In some embodiments, the nano-indium tin oxide has a particle size of 20-50 nm.

[0015] In some embodiments, the first catalyst comprises an organic solution containing ammonia, wherein the concentration of ammonia is 0.5 to 1 mol / L.

[0016] In some embodiments, the organic solvent used in the ammonia-containing organic solution includes one or more of ethanol, isopropanol, and ethylene glycol monobutyl ether.

[0017] In some embodiments, S1 specifically includes: dispersing nano-indium tin oxide in an anhydrous solvent to obtain an indium tin oxide dispersion; adjusting the temperature of the dispersion to 65-75°C, then adding the PMMA prepolymer to the dispersion, and keeping it at the temperature for 2-5 hours after the addition is complete; then adding the first catalyst and continuing to keep it at the temperature for 2-5 hours to obtain the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex.

[0018] In some embodiments, the anhydrous solvent includes ethyl acetate.

[0019] In some embodiments, the PMMA prepolymer is added to the dispersion in batches and the addition is completed in 2 to 5 hours.

[0020] In some embodiments, S2 specifically includes: first, mixing indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex and a second catalyst to form a homogeneous mixture; then, adding sebacic acid bis-2,2,6,6-tetramethylpiperidine ester in batches to the homogeneous mixture, wherein the sebacic acid bis-2,2,6,6-tetramethylpiperidine ester is added completely over 2 to 5 hours to obtain the second mixed reaction system.

[0021] In some embodiments, the reaction temperature of the second reaction is 75–85°C. Higher reaction temperatures can lead to side reactions, resulting in reduced product purity and decreased light transmittance.

[0022] In some embodiments, the reaction time of the second reaction is 2 to 5 hours.

[0023] In some embodiments, the second catalyst comprises N,N-dimethylaminopyridine.

[0024] In some embodiments, the content of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex in the second mixed reaction system is 15-20 wt%.

[0025] In some embodiments, the content of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester in the second mixed reaction system is 1-2 wt%.

[0026] The second objective of this invention is to provide a composite material with high light transmittance and ultraviolet-infrared dual blocking properties obtained by the preparation method described in any of the above technical solutions.

[0027] A third objective of this invention is to provide a heat-insulating coating, which comprises a base resin and a composite material with high light transmittance and ultraviolet-infrared dual blocking properties as described in any of the technical solutions.

[0028] In some embodiments, the composite material is present in the thermal insulation coating at a content of 10-20 wt%.

[0029] In some embodiments, the content of the matrix resin is 10-15 wt%.

[0030] In some embodiments, the heat-insulating coating includes 70% to 80 wt% of a solvent, such as one or more of ethyl acetate, toluene, isopropanol, ethylene glycol monobutyl ether, and dimethyl carbonate.

[0031] In some embodiments, the heat-insulating coating may also include 1-5% curing agent, 0.5-1% leveling agent, etc.

[0032] Existing powder-based infrared absorbers are limited by their poor dispersibility and optical properties, limiting their addition to coatings. Consequently, the heat insulation effect of heat-insulating coatings is also limited by their addition amount, resulting in poor cooling and heat insulation performance of coatings based on powder-based infrared absorbers. In contrast, the composite material prepared by this invention can be well dispersed in organic solvents, thus increasing its content in coatings can improve the ultraviolet-infrared blocking performance of the coating. Furthermore, it can maintain high visible light transmittance under high-concentration dispersion conditions. Moreover, the composite material has good compatibility and can be applied to various resin coating systems.

[0033] The fifth objective of this invention is to provide a heat-insulating coating, wherein the heat-insulating coating comprises the cured product of the heat-insulating coating described in any of the technical solutions.

[0034] In some embodiments, the heat-insulating coating has a visible light transmittance of over 70%, a blocking rate of over 95% for both infrared and ultraviolet rays, and a haze of less than 2%.

[0035] The sixth objective of this invention is to provide a light-transmitting structure, which includes the heat-insulating coating described in any of the technical solutions. This light-transmitting structure can be applied, for example, to building glass curtain walls, automobile windows, and other fields.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] (1) Nano In2O3·SnO2 itself is an opaque solid powder. The coating formed by directly preparing heat insulation coatings with it has poor light transmittance and high haze. However, the preparation method provided by this invention can transform the opaque solid powder In2O3·SnO2 into a high-transparency polymer composite material dispersion. The heat insulation coating based on this composite material has a visible light transmittance of more than 70% and a haze of less than 2%.

[0038] (2) The composite material provided by the present invention has a dual blocking function of ultraviolet and infrared, and the blocking rate of both infrared and ultraviolet is above 95%.

[0039] (3) The heat insulation coating based on the composite material has good adhesion, weather resistance and aging resistance. Detailed Implementation

[0040] The technical solutions of the present invention will be described in detail below with reference to specific embodiments, so that those skilled in the art can better understand and implement the technical solutions of the present invention. The specific functional details disclosed herein should not be construed as limiting, but are merely intended to form the basis of the claims and to teach those skilled in the art to employ the representative basis of the invention in different ways in any suitable detailed embodiment.

[0041] Unless otherwise specified, all raw materials and reagents used in the embodiments of this invention are commercially available. Specifically, the nano-sized In2O3·SnO2 powder was purchased from Kerun Nano, and the PMMA prepolymer was purchased from Hangzhou Oushi Technology Co., Ltd. Unless otherwise specified, all "%" in the specific embodiments of this invention refer to mass percentages.

[0042] Example 1

[0043] This embodiment provides a composite material with high light transmittance and dual violet-infrared blocking properties, and its preparation method, as detailed below:

[0044] 10g of nano-sized In2O3·SnO2 powder was added to a reaction vessel, followed by 400ml of ethyl acetate. The reaction vessel was heated to 65℃, and the stirring speed was adjusted to 800r / min. Then, 80g of PMMA prepolymer was added dropwise to the reaction vessel over approximately 2 hours. After the addition was complete, the mixture was kept at the desired temperature for 2 hours. Next, 20ml of ammonia (1mol / L) ethanol solution was added dropwise to the reaction vessel, and the stirring was maintained for another 2 hours. Upon completion of the reaction, indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex was obtained, which was a deep blue transparent solution with a solid content of 20%.

[0045] Add 400 ml of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex prepared above to the reaction vessel, and add 0.1 g of N,N-dimethylaminopyridine. Maintain stirring at 500 r / min and heat the reaction vessel to 75 °C. Dissolve 5 g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester in 100 ml of ethyl acetate to form sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester solution, and add it dropwise to the reaction vessel. The addition is completed in about 2 hours. After the addition is completed, maintain the reaction for 2 hours. After the reaction is completed, cool and remove from the vessel to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, which is a blue transparent solution.

[0046] A heat-insulating coating was prepared using the high light transmittance and ultraviolet-infrared dual-blocking composite material obtained above. The composition and content of the heat-insulating coating are as follows: 78% ethyl acetate solvent, 10% thermosetting acrylic resin (80% solid content), 10% of the above-prepared (20% solid content) high light transmittance and ultraviolet-infrared dual-blocking composite material, 1% blocked isocyanate as curing agent and 1% leveling agent.

[0047] The above-mentioned heat-insulating coating was applied to the glass surface to form a heat-insulating coating. The infrared and ultraviolet blocking rates, visible light transmittance and haze were tested using a spectrophotometer. The adhesion was tested according to the cross-cut adhesion test method. The test results are shown in Table 1.

[0048] Example 2

[0049] This embodiment provides a composite material with high light transmittance and dual violet-infrared blocking properties, and its preparation method, as detailed below:

[0050] 10g of nano-sized In2O3·SnO2 powder was added to a reaction vessel, followed by 400ml of ethyl acetate. The reaction vessel was heated to 70℃, and the stirring speed was adjusted to 800r / min. Then, 80g of PMMA prepolymer was added dropwise to the reaction vessel over approximately 2 hours. After the addition was complete, the mixture was kept at the same temperature for 2 hours. Next, 20ml of ammonia (1mol / L) ethanol solution was added dropwise to the reaction vessel, and the stirring was maintained for another 2 hours. Upon completion of the reaction, indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex was obtained, which was a deep blue transparent solution with a solid content of 20%.

[0051] Add 400 ml of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex prepared above to the reaction vessel, and add 0.1 g of N,N-dimethylaminopyridine. Maintain stirring at 500 r / min and heat the reaction vessel to 80 °C. Dissolve 10 g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester in 100 ml of ethyl acetate to form sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester solution, and add it dropwise to the reaction vessel. The addition is completed in about 2 hours. After the addition is completed, maintain the reaction for 2 hours. After the reaction is completed, cool and remove from the vessel to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, which is a blue transparent solution.

[0052] The coating was prepared using the same method as in Example 1, and the coating performance was tested using the same method. The test results are shown in Table 1.

[0053] Example 3

[0054] This embodiment provides a composite material with high light transmittance and dual violet-infrared blocking properties, and its preparation method, as detailed below:

[0055] 10g of nano-sized In2O3·SnO2 powder was added to a reaction vessel, followed by 400ml of ethyl acetate. The reaction vessel was heated to 75℃, and the stirring speed was adjusted to 800r / min. Then, 80g of PMMA prepolymer was added dropwise to the reaction vessel, which was completed in about 2 hours. After the addition was completed, the temperature was maintained for 2 hours. Then, 20ml of ammonia (1mol / L) ethanol solution was added dropwise to the reaction vessel, and the stirring was maintained for another 2 hours. After the reaction was completed, indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex was obtained, which was a deep blue transparent solution with a solid content of 20%.

[0056] Add 400 ml of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex prepared above to the reaction vessel, and add 0.1 g of N,N-dimethylaminopyridine. Maintain stirring at 500 r / min and heat the reaction vessel to 85 °C. Dissolve 7 g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester in 100 ml of ethyl acetate to form sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester solution, and add it dropwise to the reaction vessel. The addition is completed in about 2 hours. After the addition is completed, maintain the reaction for 2 hours. After the reaction is completed, cool and remove from the vessel to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, which is a blue transparent solution.

[0057] The coating was prepared using the same method as in Example 1, and the coating performance was tested using the same method. The test results are shown in Table 1.

[0058] Example 4

[0059] The only difference between Example 4 and Example 1 is that the reaction temperature for the complexation of In2O3·SnO2 with PMMA prepolymer is 80℃, and the reaction temperature for the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex with sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester is 90℃, as detailed below:

[0060] 10g of nano-sized In2O3·SnO2 powder was added to a reaction vessel, followed by 400ml of ethyl acetate. The reaction vessel was heated to 80℃, and the stirring speed was adjusted to 800r / min. Then, 80g of PMMA prepolymer was added dropwise to the reaction vessel, which was completed in about 2 hours. After the addition was completed, the temperature was maintained for 2 hours. Then, 20ml of ammonia (1mol / L) ethanol solution was added dropwise to the reaction vessel, and the stirring was maintained for another 2 hours. After the reaction was completed, indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex was obtained, which was a deep blue transparent solution with a solid content of 20%.

[0061] Add 400 ml of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex prepared above to the reaction vessel, and add 0.1 g of N,N-dimethylaminopyridine. Maintain stirring at 500 r / min and heat the reaction vessel to 90 °C. Dissolve 5 g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester in 100 ml of ethyl acetate to form sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester solution, and add it dropwise to the reaction vessel. The addition is completed in about 2 hours. After the addition is completed, maintain the reaction for 2 hours. After the reaction is completed, cool and remove from the vessel to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, which is a blue transparent solution.

[0062] The coating was prepared using the same method as in Example 1, and the coating performance was tested using the same method. The test results are shown in Table 1.

[0063] Example 5

[0064] This embodiment provides a composite material with high light transmittance and dual violet-infrared blocking properties, and its preparation method, as detailed below:

[0065] 25g of nano-sized In2O3·SnO2 powder was added to a reaction vessel, followed by 400ml of ethyl acetate. The reaction vessel was heated to 70℃, and the stirring speed was adjusted to 800r / min. Then, 100g of PMMA prepolymer was added dropwise to the reaction vessel over approximately 2 hours. After the addition was complete, the mixture was kept at the desired temperature for 2 hours. Next, 20ml of ammonia (1mol / L) ethanol solution was added dropwise to the reaction vessel, and the stirring was maintained for another 2 hours. Upon completion of the reaction, indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex was obtained, which was a deep blue transparent solution with a solid content of 20%.

[0066] Add 400 ml of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex prepared above to the reaction vessel, and add 0.1 g of N,N-dimethylaminopyridine. Maintain stirring at 500 r / min and heat the reaction vessel to 80 °C. Dissolve 5 g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester in 100 ml of ethyl acetate to form sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester solution, and add it dropwise to the reaction vessel. The addition is completed in about 2 hours. After the addition is completed, maintain the reaction for 2 hours. After the reaction is completed, cool and remove from the vessel to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, which is a blue transparent solution.

[0067] The coating was prepared using the same method as in Example 1, and the coating performance was tested using the same method. The coating performance obtained in this example is comparable to that in Example 1.

[0068] Example 6

[0069] This embodiment provides a composite material with high light transmittance and dual violet-infrared blocking properties, and its preparation method, as detailed below:

[0070] 15g of nano-sized In2O3·SnO2 powder was added to a reaction vessel, followed by 400ml of ethyl acetate. The reaction vessel was heated to 70℃, and the stirring speed was adjusted to 800r / min. Then, 90g of PMMA prepolymer was added dropwise to the reaction vessel over approximately 2 hours. After the addition was complete, the mixture was kept at the desired temperature for 2 hours. Next, 20ml of ammonia (1mol / L) ethanol solution was added dropwise to the reaction vessel, and the stirring was maintained for another 2 hours. Upon completion of the reaction, indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex was obtained, which was a deep blue transparent solution with a solid content of 20%.

[0071] Add 400 ml of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex prepared above to the reaction vessel, and add 0.1 g of N,N-dimethylaminopyridine. Maintain stirring at 500 r / min and heat the reaction vessel to 80 °C. Dissolve 7.5 g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester in 100 ml of ethyl acetate to form sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester solution, and add it dropwise to the reaction vessel. The addition is completed in about 2 hours. After the addition is completed, maintain the reaction for 2 hours. After the reaction is completed, cool and remove from the vessel to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, which is a blue transparent solution.

[0072] The coating was prepared using the same method as in Example 1, and the coating performance was tested using the same method. The coating performance obtained in this example is comparable to that in Example 1.

[0073] Example 7

[0074] The only difference between Example 7 and Example 1 is that 5g of nano-sized In2O3·SnO2 powder, 80g of PMMA prepolymer, and 0.5g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester were used in the preparation process, while the rest were carried out in the same manner as in Example 1.

[0075] Example 8

[0076] The only difference between Example 8 and Example 1 is that 10g of nano-sized In2O3·SnO2 powder, 40g of PMMA prepolymer, and 1g of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester were used in the preparation process, while the rest were carried out in the same manner as in Example 1.

[0077] Comparative Example 1

[0078] The composition of the heat-insulating coating in Comparative Example 1 was: 78% ethyl acetate solvent, 10% thermosetting acrylic resin (80% solids), 1% curing agent, 1% leveling agent, and 10% barrier material. The barrier material comprised nano-sized In₂O₃·SnO₂ powder, PMMA prepolymer, and bis-2,2,6,6-tetramethylpiperidinol sebacate in a mass ratio of 10:80:1. The remaining procedures were the same as in Example 1. It was found that compared to Example 1, the coating prepared in Comparative Example 1 exhibited significantly increased haze and decreased visible light transmittance.

[0079] Table 1. Relevant performance of the heat-insulating coatings in the examples and comparative examples.

[0080]

[0081]

[0082] All aspects, embodiments, features, and examples of this invention are to be regarded as illustrative in all respects and are not intended to limit the invention, the scope of which is defined only by the claims. Other embodiments, modifications, and uses will become apparent to those skilled in the art without departing from the spirit and scope of the invention as claimed.

[0083] In addition, the inventors of this case also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.

[0084] Although the invention has been described with reference to illustrative embodiments, those skilled in the art will understand that various other changes, omissions, and / or additions can be made without departing from the spirit and scope of the invention, and that elements of the embodiments can be substituted with substantially equivalents. Furthermore, many modifications can be made without departing from the scope of the invention to adapt particular situations or materials to the teachings of the invention. Therefore, this invention is not intended to be limited to the specific embodiments disclosed for carrying out the invention, but rather is intended to encompass all embodiments falling within the scope of the appended claims. Moreover, unless specifically stated otherwise, any use of the terms first, second, etc., does not indicate any order or importance, but is used to distinguish one element from another.

Claims

1. A method for preparing a composite material with high light transmittance and ultraviolet-infrared dual blocking properties, characterized in that, include: S1: The first mixed reaction system containing nano-indium tin oxide, PMMA prepolymer and the first catalyst is subjected to the first reaction to obtain indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex; S2: A second reaction is carried out in a second mixed reaction system containing indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex, sebacic acid bis-2,2,6,6-tetramethylpiperidine ester and a second catalyst to obtain a composite material with high light transmittance and ultraviolet-infrared dual blocking.

2. The preparation method according to claim 1, characterized in that: In the first mixed reaction system, the content of nano-indium tin oxide is 2-5 wt%; and / or, the content of PMMA prepolymer is 15-20 wt%. And / or, the reaction temperature of the first mixed reaction system is 65–75°C; And / or, both the first and second reactions are carried out under anhydrous conditions; And / or, the number-average molecular weight of the PMMA prepolymer is 10,000-100,000; And / or, the particle size of the nano-indium tin oxide is 20-50 nm; And / or, the first catalyst comprises an organic solution containing ammonia, wherein the concentration of ammonia is 0.5-1 mol / L.

3. The preparation method according to claim 2, characterized in that, S1 specifically includes: dispersing nano-indium tin oxide in an anhydrous solvent to obtain an indium tin oxide dispersion; adjusting the temperature of the dispersion to 68-72°C, then adding the PMMA prepolymer to the dispersion, and keeping it at the temperature for 2-5 hours after the addition is complete; then adding the first catalyst and continuing to keep it at the temperature for 2-5 hours to obtain the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex.

4. The preparation method according to claim 3, characterized in that: The anhydrous solvent includes one or more of ethyl acetate, dimethyl carbonate, and dimethylformamide; And / or, the PMMA prepolymer is added to the dispersion in batches and the addition is completed in 2 to 5 hours.

5. The preparation method according to claim 1, characterized in that, S2 specifically includes: first, mixing the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex and the second catalyst to form a homogeneous mixture; then, adding bis-2,2,6,6-tetramethylpiperidine sebacate to the homogeneous mixture in batches, with the addition of bis-2,2,6,6-tetramethylpiperidine sebacate completed in 2-5 hours, to obtain the second mixed reaction system.

6. The preparation method according to claim 1 or 5, characterized in that: The reaction temperature of the second reaction is 75–85°C; and / or the reaction time of the second reaction is 2–5 h; And / or, the second catalyst comprises N,N-dimethylaminopyridine; And / or, in the second mixed reaction system, the content of the indium tin oxide poly[1-(methoxycarbonylmethyl)ethylene] complex is 15-20 wt%; And / or, in the second mixed reaction system, the content of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester is 1-2 wt%.

7. The composite material with high light transmittance and ultraviolet-infrared dual blocking obtained by the preparation method according to any one of claims 1 to 6.

8. A heat-insulating coating, characterized in that, The heat-insulating coating comprises a base resin and a composite material with high light transmittance and ultraviolet-infrared dual blocking as described in claim 7.

9. A heat-insulating coating, characterized in that, The heat-insulating coating comprises the cured product of the heat-insulating coating of claim 8; Preferably, the heat-insulating coating has a visible light transmittance of 70% or more, a blocking rate of 95% or more for both infrared and ultraviolet rays, and a haze of less than 2%.

10. A light-transmitting structure, characterized in that, The light-transmitting structure includes the heat-insulating coating as described in claim 9.

Images