Colored heat-insulating aerogel as well as preparation method and application thereof

Abstract

The colored heat-insulating aerogel and the preparation method and application thereof are provided for the first time, metal ions are adsorbed on the surface of graphene oxide through the adsorption effect of oxygen-containing functional groups on the surface of graphene oxide on the metal ions, a water-plastic foaming method is used, and foaming and subsequent plasticizing processes are reasonably controlled, so that the color heat-insulating aerogel is obtained. The surface tension of a solvent is utilized to enhance the interface bonding of a foamed graphene aerogel skeleton, a surface-to-surface lapped graphene continuous dome network is formed, a thermal shock rapid heating and cooling mode is used, a graphene oxide sacrificial template is removed, uniform and fine metal oxide nanoparticles are formed, aggregation of the metal oxide nanoparticles is inhibited, and the graphene aerogel is prepared. The size of metal oxide nanoparticles is reduced, the metal oxide ceramic with a similar graphene aerogel continuous dome network structure can be obtained, and the prepared colorful ceramic is placed in customized laminated glass, so that the laminated glass has the properties of heat insulation and specific wavelength light absorption.

Description

Technical Field

[0001] The invention belongs to the technical field of functional materials, and in particular relates to a colored thermal insulation aerogel and a preparation method and application thereof. Background Art

[0002] Laminated glass is a composite glass product made of two or more pieces of glass with one or more layers of organic polymer interlayer in between. After special high-temperature pre-pressing (or vacuuming) and high-temperature and high-pressure processing, the glass and the interlayer are permanently bonded together. Although laminated glass performs well in terms of safety, sound insulation and UV protection, it has obvious deficiencies in thermal insulation performance: traditional laminated glass has poor thermal insulation and cannot effectively block external heat, causing indoor temperature to rise and affecting living comfort; under long-term sunlight exposure, the outer panel of laminated glass will gradually age and turn yellow, which not only affects the appearance of the building, but also causes the loosening of the glass joints, reducing the stability and service life of the overall structure; due to poor thermal insulation performance, more air conditioning and cooling are required in summer to maintain indoor temperature, increasing energy consumption and operating costs; under extreme climatic conditions, the thermal insulation effect of traditional laminated glass is even more limited, and it is difficult to meet the requirements of high-efficiency buildings. Summary of the invention

[0003] In view of the problem that the existing laminated glass has insufficient heat insulation effect, the present invention provides a colored heat-insulating aerogel laminated glass. This colored ceramic heat-insulating aerogel composed of ultra-small nanoparticles, which is made by a thermal shock method, has the advantages of high transparency, strong heat insulation and high elasticity as a glass interlayer. The colored heat-insulating aerogel laminated glass successfully combines traditional laminated glass with a new type of aerogel material, achieving higher heat insulation performance, while having a color effect, having the absorption capacity of a specific wavelength spectrum and having a certain degree of transparency.

[0004] One of the technical solutions of the present invention is to provide a method for preparing a colored thermal insulation aerogel, which specifically comprises the following steps: (1) applying a graphene oxide aqueous dispersion by scraping, drying to form a film, and then placing the film in a metal salt solution containing aluminum chloride to soak the loaded metal ions; (2) Foaming in a foaming agent; (3) After drying at room temperature, a heat shock treatment is performed, wherein the temperature of the heat shock treatment is 600-800 degrees Celsius, the heating rate of the heat shock is 500°C / s, and the cooling rate is 1000°C / s.

[0005] Furthermore, the metal salt solution also includes one or more of ferric chloride, chromium chloride and cobalt chloride. To maintain the transparency of the colored glass, the molar ratio of ferric chloride to aluminum chloride is less than 0.1, the molar ratio of cobalt chloride to aluminum chloride is less than 0.2, and the molar ratio of chromium chloride to aluminum chloride is less than 0.5.

[0006] Furthermore, the foaming agent is a 5-20% hydrazine hydrate aqueous solution, and the foaming time is 1-3 hours.

[0007] Furthermore, the temperature of the thermal shock treatment in step 4 is 600-800 degrees Celsius, the heating rate of the thermal shock is 500°C / s, and the cooling rate is 1000°C / s. The thermal shock should be performed on a boron nitride substrate.

[0008] Using thermal shock to treat aerogels can remove graphene while causing metal precursors (such as aluminum, iron, cobalt, etc.) in the aerogel to undergo oxidation reactions due to high temperatures to form corresponding oxide nanoparticles. Due to the rapid heating method of increasing and decreasing the temperature, the metal oxide nanoparticles do not have time to aggregate. Compared with traditional heating methods such as muffle furnaces, the metal oxide nanoparticles formed will be smaller. Since these nanoparticles are very small in size, they have a weaker scattering effect on light, so the resulting aerogel has a higher degree of transparency.

[0009] The present invention uses alumina aerogel as a matrix and adds metal salts such as iron oxide, chromium oxide, and cobalt oxide as coloring raw materials. Alumina aerogel has the characteristic of high transparency and can be effectively applied to glass interlayers, so that the laminated glass has good heat insulation effect while maintaining transparency.

[0010] The second technical solution of the present invention is to provide a colored thermal insulation aerogel prepared by the above preparation method, wherein the density of the colored thermal insulation aerogel is 1-6 mg / cm 3 .

[0011] The third technical solution of the present invention is to provide a glass having the above-mentioned colored thermal insulation aerogel as an interlayer. The specific method is to adopt the above-mentioned method to obtain a continuous dome network of colored ceramic aerogel, and place it in a laminated glass to obtain a colored aerogel laminated glass. The continuous network of ceramic aerogel prepared by the method of the present invention is colored by metal oxides, so adjusting the type of metal oxide can achieve the change of ceramic color. The continuous dome structure gives the ceramic high elasticity and high porosity, thereby obtaining a highly thermally insulating ceramic aerogel material. It has great application potential in the fields of thermal management, optical switching, etc.

[0012] Furthermore, the metal oxides are color-sensitive, with iron oxide being red, chromium oxide being green, and spinel structure crystals formed by cobalt oxide and aluminum oxide being blue.

[0013] Furthermore, the laminated glass is high-purity silica laminated glass.

[0014] A fourth technical solution of the present invention is to provide an application of the above-mentioned laminated glass in the fields of light absorption, heat insulation and optical switching.

[0015] The beneficial effects of the present invention are: (1) By using graphene as a template, metal ions are adsorbed on the oxygen-containing functional groups of graphene, and then a continuous dome network structure is formed by a foaming method. The ceramic aerogel obtained by the thermal shock method has high transparency, low density, high elasticity, and high thermal insulation properties.

[0016] (2) By placing colored ceramic aerogel in laminated glass, it has the characteristics of high heat insulation and the ability to absorb specific wavelengths. Its thermal diffusion coefficient is lower than that of laminated air glass, which is 0.529 mm 2 / s, thermal diffusion coefficient reaches 0.369mm 2 / s. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the SEM image of the colored thermal insulation aerogel obtained in Example 1.

[0018] Figure 2 Schematic photos of the colored thermal insulation aerogel laminated glass obtained in Example 1, Example 3, and Example 4. DETAILED DESCRIPTION

[0019] The following examples are used to further illustrate the present invention, and their purpose is to illustrate the present invention and should not be construed as limiting the scope of the present invention. Unless otherwise specified, all parts by weight and weight percentages are used below.

[0020] The raw materials used in the present invention, unless otherwise specified, are conventional commercially available products; the methods used in the present invention, unless otherwise specified, are conventional methods in the art.

[0021] The embodiments of the present invention are further described below with reference to a plurality of embodiments.

[0022] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0023] Example 1 The concentration was 10 mg / cm 3The graphene oxide solution (purchased from Hangzhou Gaoxin Technology Co., Ltd.) was scraped and dried to form a film, and then it was placed in a solution with a molar content ratio of 1:5 of 10 mg / g cobalt chloride and aluminum chloride and immersed for 6 hours. After being immersed and dried, it was placed in a 10% hydrazine hydrate solution for foaming for 1 hour, and then immersed in anhydrous ethanol solution to replace the foaming agent. After replacement, it was taken out and dried, and thermal shock was performed on a boron nitride substrate. The temperature of the thermal shock treatment was 800°C, the heating rate of the thermal shock was 500°C / s, and the cooling rate was 1000°C / s. Cobalt oxide and aluminum oxide ceramic aerogels with a continuous dome network structure were obtained, and the aerogels were blue. The density of the blue ceramic aerogel is 2.03 mg / cm 3 , the thermal diffusion coefficient is 0.416mm 2 / s.

[0024] Example 2 The concentration was 10 mg / cm 3 The graphene oxide solution (purchased from Hangzhou Gaoxin Technology Co., Ltd.) was scraped and dried to form a film, and then it was placed in a solution with a molar content ratio of chromium chloride and aluminum chloride of 10 mg / g and soaked for 6 hours. After soaking, it was taken out and dried, and then placed in a 5% hydrazine hydrate solution for foaming for 3 hours. It was then soaked in anhydrous ethanol solution to replace the foaming agent. After replacement, it was taken out and dried, and thermal shock was performed on a boron nitride substrate. The temperature of the thermal shock treatment was 600°C, the heating rate of the thermal shock was 500°C / s, and the cooling rate was 1000°C / s. Chromium oxide and aluminum oxide ceramic aerogels with a continuous dome network structure were obtained, and the aerogels were green. The density of the above green ceramic aerogel is 1.96 mg / cm 3 , the thermal diffusion coefficient is 0.439mm 2 / s.

[0025] Example 3 The concentration was 10 mg / cm 3 The graphene oxide solution (purchased from Hangzhou Gaoxin Technology Co., Ltd.) was scraped and dried to form a film, and then it was placed in a solution with a molar content ratio of 10 mg / g of ferric chloride and aluminum chloride of 1:1 and soaked for 10 hours. After soaking, it was taken out and dried, and then placed in a 20% hydrazine hydrate solution for foaming for 1 hour, and then soaked in anhydrous ethanol solution to replace the foaming agent. After replacement, it was taken out and dried, and thermal shock was performed on a boron nitride substrate. The temperature of the thermal shock treatment was 600°C, the heating rate of the thermal shock was 500°C / s, and the cooling rate was 1000°C / s. Iron oxide and aluminum oxide ceramic aerogels with a continuous dome network structure were obtained, and the aerogels were red. The density of the red ceramic aerogel is 2.08 mg / cm 3 , the thermal diffusion coefficient is 0.369mm 2 / s.

[0026] Example 4 The concentration was 10 mg / cm 3 The graphene oxide solution (purchased from Hangzhou Gaoxin Technology Co., Ltd.) was scraped and dried to form a film, and then it was placed in a 10mg / g aluminum chloride solution and soaked for 10 hours. After soaking, it was taken out and dried, and then placed in a 10% hydrazine hydrate solution for foaming for 1 hour. Then it was soaked in anhydrous ethanol solution to replace the foaming agent. After replacement, it was taken out and dried, and thermal shock was performed on a boron nitride substrate. The temperature of the thermal shock treatment was 600°C, the heating rate of the thermal shock was 500°C / s, and the cooling rate was 1000°C / s. Alumina ceramic aerogel with a continuous dome network structure was obtained, and the aerogel was white. The density of the white ceramic aerogel is 1.82mg / cm 3 , thermal diffusion coefficient is 0.410mm 2 / s.

[0027] The above embodiments describe in detail the structure, features and effects of the present invention. The above are only preferred embodiments of the present invention. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which do not exceed the scope covered by the specification, should be within the protection scope of the present invention.

Claims

1. A method for preparing a colored thermal insulation aerogel, characterized in that: The following steps are involved: (1) applying a graphene oxide aqueous dispersion by scraping, drying to form a film, and then immersing the film in a metal salt solution containing aluminum chloride for 6-10 hours to load metal ions; (2) Foaming in a foaming agent; (3) After drying at room temperature, a heat shock treatment is performed, wherein the temperature of the heat shock treatment is 600-800 degrees Celsius, the heating rate of the heat shock is 500°C / s, and the cooling rate is 1000°C / s.

2. The preparation method according to claim 1, characterized in that: The foaming agent is a 5-20% hydrazine hydrate aqueous solution, and the foaming time is 1-3 hours.

3. The preparation method according to claim 1, characterized in that: The metal salt solution also includes one or more of ferric chloride, chromium chloride, and cobalt chloride; The molar ratio of ferric chloride to aluminum chloride is less than 0.1, the molar ratio of cobalt chloride to aluminum chloride is less than 0.2, and the molar ratio of chromium chloride to aluminum chloride is less than 0.

5.

4. A colored thermal insulation aerogel prepared by the preparation method as claimed in claim 1.

5. The colored thermal insulation aerogel according to claim 4, characterized in that: The density of the colored thermal insulation aerogel is 1-6 mg / cm 3 .

6. A glass, characterized in that: The colored thermal insulation aerogel described in claim 4 is used as an interlayer.

7. Use of the laminated glass as claimed in claim 6 in the fields of light absorption, heat insulation and optical switching.

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