Radiation refrigeration filler as well as preparation method and application thereof

Abstract

The invention discloses a radiation refrigeration filler as well as a preparation method and application thereof, and belongs to the technical field of coatings. The radiation refrigeration filler is prepared from yttrium oxide, gadolinium oxide, lutetium oxide and other rare earth Yakadu, the rare earth oxides have high emissivity in the 8-13 wave band, and meanwhile, the rare earth elements have a unique electronic structure, so that the prepared radiation refrigeration filler can absorb and emit heat radiation electromagnetic waves in a spectrum; therefore, a good cooling effect is achieved. When the radiation refrigeration filler is prepared, a process of calcining and annealing treatment is adopted, so that the prepared radiation refrigeration filler forms a porous structure on a micro-level, the reflecting surface of the filler is increased due to the existence of the porous structure, sunlight and ambient refracted light can be reflected for multiple times, infrared radiation shielding is avoided, and the radiation refrigeration efficiency is enhanced.

Description

Technical Field

[0001] The present invention belongs to the technical field of coatings, and particularly relates to a radiative cooling filler, a preparation method thereof, and an application thereof. Background Art

[0002] Radiative cooling coatings are a new type of environmentally friendly and energy-saving cooling material, which achieve a cooling effect by highly reflecting sunlight and having a high infrared emissivity. Compared with traditional air-conditioning cooling systems, radiative cooling coatings have the following remarkable advantages: 1. No power consumption: Radiative cooling coatings do not require the consumption of electric energy or other energy sources, and completely rely on natural physical processes to achieve cooling, so they have extremely high environmental friendliness and economy.

[0003] 2. Green and environmentally friendly: Radiative cooling coatings do not use any chemical refrigerants and do not produce pollutant emissions, and are a safe and environmentally friendly cooling product.

[0004] 3. Simple construction: Radiative cooling coatings can be constructed like ordinary coatings, with simple operation and easy maintenance.

[0005] Radiative cooling coatings are a new type of environmentally friendly and energy-saving cooling material, which have many advantages, but there are also some potential disadvantages that need to be considered in practical applications: 1. High cost: The preparation of radiative cooling coatings requires the use of special materials and processes, so the cost is relatively high, especially for large-area applications.

[0006] 2. Durability issues: The durability of some radiative cooling coatings is limited, and their performance may be lost over time, requiring regular maintenance or replacement.

[0007] In patent CN113999585A, a thermochromic radiative cooling coating is formed by mixing and stirring functional materials such as a thermosensitive resin, a radiative agent, and a reflector in a coating system. The patent tests that after the cooling coating film has changed color 1000 times repeatedly, its color-changing performance and radiative cooling performance are still stable; however, when this material is actually used, ultraviolet rays will accelerate the decomposition of chemical substances in the thermosensitive layer and the fading of color. In patent CN115418148A, by adding dioctyl succinate imide, polyacrylate and L-2-amino-3-indolylpropionic acid are combined to form an oxygen free radical consumption layer outside the thermochromic microcapsule, avoiding the core material of the thermochromic microcapsule from being invaded under the conditions of light or high temperature and losing its color-changing performance, but this organic reversible thermochromic exterior wall coating will release VOCs accordingly. Summary of the Invention

[0008] In view of the above-mentioned prior art, the present invention provides a radiative cooling filler, a preparation method thereof and an application thereof, so as to solve the technical problems of poor reflection effect of existing radiative cooling coatings on sunlight and low infrared emissivity.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is to provide a preparation method of a radiative cooling filler, comprising the following steps: S1: Mix yttrium oxide, gadolinium oxide, lutetium oxide and vanadium trioxide to obtain a mixture; S2: Calcinate the mixture at 550-650 °C for 4-8 h, and then air-cool to room temperature to obtain a crude product; S3: Heat the crude product to 580-620 °C, keep it warm for 2-4 h, then cool it to 100 °C within 1 h, and then air-cool to room temperature to obtain the product.

[0010] On the basis of the above technical solution, the present invention can also be improved as follows.

[0011] Further, the mass ratio of yttrium oxide, gadolinium oxide, lutetium oxide and vanadium trioxide in the mixture is 1:1:1:1.

[0012] Further, the calcination temperature in S2 is 600 °C and the calcination time is 6 h.

[0013] Further, the heating rate in S3 is 5-10 °C / min; the final heating temperature is 600 °C and the heat preservation time is 3 h.

[0014] The present invention also discloses a radiative cooling filler prepared by the above preparation method.

[0015] The present invention also discloses the application of the above radiative cooling filler in the preparation of a radiative cooling coating.

[0016] Further, the radiative cooling coating comprises the following components in parts by mass: Dispersant 0.1 part, thickener 0.6 part, defoamer 0.2 part, radiative cooling filler 15-30 parts, fluorocarbon emulsion 17-20 parts, filler 10-15 parts, alumina 5-12 parts, zirconia 5-12 parts, barium sulfate 0-13 parts, auxiliary agent 1 part and water 18.8 parts.

[0017] Further, the radiative cooling coating comprises the following components in parts by mass: Dispersant 0.1 part, thickener 0.6 part, defoamer 0.2 part, radiative cooling filler 20 parts, fluorocarbon emulsion 20 parts, filler 15 parts, alumina 12 parts, zirconia 10 parts, auxiliary agent 1 part and water 18.8 parts.

[0018] Further, the dispersant is 1124; the thickener is HBR250; the defoamer is BYK-028; the filler is R699; the auxiliary agent is a film-forming auxiliary agent.

[0019] Furthermore, the film-forming auxiliary is lauryl alcohol phthalate.

[0020] The beneficial effects of the present invention are as follows: 1. The radiative cooling filler in the present invention is prepared from rare earth oxides such as yttrium oxide, gadolinium oxide, and lutetium oxide. These rare earth oxides have a high emissivity in the 8-13 μm band. At the same time, rare earth elements have a unique electronic structure, enabling the prepared radiative cooling filler to absorb and emit thermal radiation electromagnetic waves in the spectrum, thereby producing a good cooling effect.

[0021] 2. When preparing the radiative cooling filler in the present invention, a process of first calcining and then annealing treatment is adopted, so that the prepared radiative cooling filler forms a porous structure at the microscopic level. The existence of the porous structure will increase the reflecting surface of the filler, which can reflect sunlight and ambient refracted light multiple times without infrared radiation shielding, and enhance the radiative cooling efficiency.

[0022] 3. The radiative cooling filler in the present invention can be added into the coating as a filler of the coating. After the obtained coating is applied as a topcoat, it can form a multi-directional reflecting and radiative surface convex to the base surface on the surface, so as to strongly reflect sunlight, and thus achieve the purpose of cooling. Specific Embodiments

[0023] The dispersant used in the present invention is 1124 (DOW), the thickener is cellulose ether HBR250 (Ashland), the defoamer is BYK-028 (BYK), and the film-forming auxiliary is lauryl alcohol phthalate (Eastman Chemical); the filler is R699 (rutile titanium dioxide, purchased from Longmang Bailian); zirconia and alumina are purchased from Xi'an Fangke New Materials Co., Ltd.; barium sulfate is purchased from Wuhan Karnos Technology Co., Ltd.; the fluorocarbon emulsion is Ruifeng RF-903 waterborne fluorinated acrylate-based fluorosilicone resin.

[0024] The following will describe the specific embodiments of the present invention in detail with reference to the examples.

[0025] Example 1 A radiative cooling coating, comprising the following components in parts by mass: 0.1 part of 1124, 0.6 part of HBR250, 0.2 part of BYK-028, 20 parts of radiative cooling filler, 20 parts of fluorocarbon emulsion, 15 parts of R699, 12 parts of alumina, 10 parts of zirconia, 1 part of lauryl alcohol phthalate, and 18.8 parts of water.

[0026] Among them, the radiative cooling filler is prepared through the following steps: S1: Mix yttrium oxide (Y2O3), gadolinium oxide (Gd2O3), lutetium oxide (Lu2O3) and vanadium trioxide (V2O3) in a mass ratio of 1:1:1:1 to obtain a mixture; S2: Calcinate the mixture at 600 °C for 6 h, then air-cool to room temperature to obtain a crude product; S3: Heat the crude product to 600 °C at a heating rate of 5 °C / min, hold for 3 h, then cool to 100 °C within 1 h, and then air-cool to room temperature to obtain the product.

[0027] The radiation cooling coating in this example is prepared through the following steps: Add the components in the formula amount to water and stir evenly to obtain the product.

[0028] Example 2 A radiation cooling coating, comprising the following components in parts by mass: 1124 0.1 part, HBR250 0.6 part, BYK-028 0.2 part, radiation cooling filler 15 parts, fluorocarbon emulsion 17.5 parts, R699 10 parts, alumina 10 parts, zirconia 12 parts, barium sulfate 12.5 parts, alcohol ester twelve 1 part and water 18.8 parts.

[0029] Among them, the radiation cooling filler is prepared through the following steps: S1: Mix yttrium oxide (Y2O3), gadolinium oxide (Gd2O3), lutetium oxide (Lu2O3) and vanadium trioxide (V2O3) in a mass ratio of 1:1:1:1 to obtain a mixture; S2: Calcinate the mixture at 550 °C for 8 h, then air-cool to room temperature to obtain a crude product; S3: Heat the crude product to 580 °C at a heating rate of 5 °C / min, hold for 4 h, then cool to 100 °C within 1 h, and then air-cool to room temperature to obtain the product.

[0030] The radiation cooling coating in this example is prepared through the following steps: Add the components in the formula amount to water and stir evenly to obtain the product.

[0031] Example 3 A radiation cooling coating, comprising the following components in parts by mass: 1124 0.1 part, HBR250 0.6 part, BYK-028 0.2 part, radiation cooling filler 30 parts, fluorocarbon emulsion 18 parts, R699 10 parts, alumina 5 parts, zirconia 5 parts, barium sulfate 8 parts, alcohol ester twelve 1 part and water 18.8 parts.

[0032] Among them, the radiation cooling filler is prepared through the following steps: S1: Mix yttrium oxide (Y2O3), gadolinium oxide (Gd2O3), lutetium oxide (Lu2O3) and vanadium trioxide (V2O3) in a mass ratio of 1:1:1:1 to obtain a mixture; S2: Calcinate the mixture at 650 °C for 4 h, and then air-cool it to room temperature to obtain a crude product; S3: Heat the crude product to 620 °C at a heating rate of 10 °C / min, hold for 2 h, then cool it to 100 °C within 1 h, and then air-cool it to room temperature to obtain the product.

[0033] The radiation cooling coating in this example is prepared through the following steps: Add the components in the formula amount to water and stir evenly to obtain the product.

[0034] Comparative Example 1 A radiation cooling coating, comprising the following components in parts by mass: 1124 0.1 part, HBR250 0.6 parts, BYK-028 0.2 parts, fluorocarbon emulsion 20 parts, R699 15 parts, alumina 8 parts, zirconia 9 parts, barium sulfate 25 parts, alcohol ester twelve 1 part and water 18.8 parts.

[0035] The radiation cooling coating in this comparative example is prepared through the following steps: Add the components in the formula amount to water and stir evenly to obtain the product.

[0036] Comparative Example 2 A radiation cooling coating, comprising the following components in parts by mass: 1124 0.1 part, HBR250 0.6 parts, BYK-028 0.2 parts, radiation cooling filler 20 parts, fluorocarbon emulsion 20 parts, alumina 12 parts, zirconia 10 parts, barium sulfate 25 parts, alcohol ester twelve 1 part and water 18.8 parts.

[0037] Among them, the radiation cooling filler is prepared through the following steps: S1: Mix yttrium oxide (Y2O3), gadolinium oxide (Gd2O3), lutetium oxide (Lu2O3) and vanadium trioxide (V2O3) in a mass ratio of 1:1:1:1 to obtain a mixture; S2: Calcinate the mixture at 600 °C for 6 h, and then air-cool it to room temperature to obtain a crude product; S3: Heat the crude product to 600 °C at a heating rate of 5 °C / min, hold for 3 h, then cool it to 100 °C within 1 h, and then air-cool it to room temperature to obtain the product.

[0038] The radiation cooling coating in this comparative example is prepared through the following steps: Add the components in the formula amount to water and stir evenly to obtain the product.

[0039] Comparative Example 3 A radiative cooling coating, comprising components in the following parts by mass: 1124 0.1 part, HBR250 0.6 parts, BYK-028 0.2 parts, radiative cooling filler 20 parts, fluorocarbon emulsion 20 parts, R699 15 parts, zirconia 10 parts, barium sulfate 12 parts, alcohol ester 12 1 part and water 18.8 parts.

[0040] Among them, the radiative cooling filler is prepared through the following steps: S1: Mix yttrium oxide (Y2O3), gadolinium oxide (Gd2O3), lutetium oxide (Lu2O3) and vanadium trioxide (V2O3) in a mass ratio of 1:1:1:1 to obtain a mixture; S2: Calcinate the mixture at 600°C for 6 h, and then air-cool to room temperature to obtain a crude product; S3: Heat the crude product to 600°C at a heating rate of 5°C / min, hold for 3 h, then cool to 100°C within 1 h, and then air-cool to room temperature to obtain the product.

[0041] The radiative cooling coating in this comparative example is prepared through the following steps: Add the components in the formula amount to water and stir evenly to obtain the product.

[0042] Comparative Example 4 A radiative cooling coating, comprising components in the following parts by mass: 1124 0.1 part, HBR250 0.6 parts, BYK-028 0.2 parts, radiative cooling filler 20 parts, fluorocarbon emulsion 20 parts, R699 15 parts, alumina 12 parts, barium sulfate 10 parts, alcohol ester 12 1 part and water 18.8 parts.

[0043] Among them, the radiative cooling filler is prepared through the following steps: S1: Mix yttrium oxide (Y2O3), gadolinium oxide (Gd2O3), lutetium oxide (Lu2O3) and vanadium trioxide (V2O3) in a mass ratio of 1:1:1:1 to obtain a mixture; S2: Calcinate the mixture at 600°C for 6 h, and then air-cool to room temperature to obtain a crude product; S3: Heat the crude product to 600°C at a heating rate of 5°C / min, hold for 3 h, then cool to 100°C within 1 h, and then air-cool to room temperature to obtain the product.

[0044] The radiative cooling coating in this comparative example is prepared through the following steps: Add the components in the formula amount to water and stir evenly to obtain the product.

[0045] Experimental Example The performance of the radiative cooling coatings prepared in the above-mentioned examples and comparative examples was tested by the method described in GB / T 9755-2014, and the results are shown in Table 1.

[0046] Table 1 Performance of the radiative cooling coatings Example 1 Example 2 Example 3 Comparison 1 Comparison 2 Comparison 3 Comparison 4 Coating performance Qualified Qualified Qualified Qualified Unqualified Qualified Qualified Solar reflectance 0.95 0.93 0.92 0.8 0.7 0.74 0.76 Emissivity at 8 - 13 microns 0.98 0.96 0.92 0.86 0.82 0.87 0.88 Although the specific implementation manners of the present invention have been described in detail in conjunction with the embodiments, it should not be construed as a limitation on the protection scope of this patent. Within the scope described in the claims, various modifications and deformations that can be made by those skilled in the art without creative efforts still fall within the protection scope of this patent.

Claims

1. A preparation method of a radiative cooling filler, characterized in that, It includes the following steps: S1: Mix yttrium oxide, gadolinium oxide, lutetium oxide and vanadium trioxide to obtain a mixture; S2: Calcinate the mixture at 550 - 650 °C for 4 - 8 h, then air-cool to room temperature to obtain a crude product; S3: Heat the crude product to 580 - 620 °C, keep it warm for 2 - 4 h, then cool it to 100 °C within 1 h, and then air-cool to room temperature to obtain the product.

2. The preparation method according to claim 1, characterized in that: The mass ratio of yttrium oxide, gadolinium oxide, lutetium oxide and vanadium trioxide in the mixture is 1:1:1:

1.

3. The preparation method according to claim 1, wherein: In S2, the calcination temperature is 600 °C and the calcination time is 6 h.

4. The preparation method according to claim 1, wherein: In S3, the heating rate is 5 - 10 °C / min; the final heating temperature is 600 °C and the heat preservation time is 3 h.

5. The radiative cooling filler prepared by the preparation method according to any one of claims 1 - 4.

6. The application of the radiative cooling filler according to claim 5 in the preparation of radiative cooling coatings.

7. The application according to claim 6, characterized in that The radiative cooling coating comprises the following components in parts by mass: Dispersant 0.1 part, thickener 0.6 part, defoamer 0.2 part, radiative cooling filler 15 - 30 parts, fluorocarbon emulsion 17 - 20 parts, filler 10 - 15 parts, alumina 5 - 12 parts, zirconia 5 - 12 parts, barium sulfate 0 - 13 parts, auxiliary agent 1 part and water 18.8 parts.

8. The application according to claim 7, wherein The radiative cooling coating comprises the following components in parts by mass: Dispersant 0.1 part, thickener 0.6 part, defoamer 0.2 part, radiative cooling filler 20 parts, fluorocarbon emulsion 20 parts, filler 15 parts, alumina 12 parts, zirconia 10 parts, auxiliary agent 1 part and water 18.8 parts.

9. The application according to claim 7 or 8, characterized in that: The dispersant is 1124; the thickener is HBR250; the defoamer is BYK - 028; the filler is R699; the auxiliary agent is a film-forming auxiliary agent.

10. The application according to claim 9, wherein: The film-forming auxiliary agent is alcohol ester twelve.