Cooling anti-radiation coating and preparation method thereof

Abstract

The invention discloses a cooling anti-radiation coating and a preparation method thereof. The cooling anti-radiation coating comprises a surface coating, a middle coating and a bottom coating, the surface coating comprises the following components in percentage by weight: 40-60% of polyethylene, 1-5% of carbon nanotubes, 1-5% of graphene oxide, 10-15% of a dispersant, 5-8% of polyethylene glycol, 3-8% of nano barium oxide and 3-10% of nano boron nitride. The intermediate coating comprises the following components in percentage by weight: 50%-70% of polyurethane, 20%-30% of a silane coupling agent and 5%-10% of aluminum oxide; the bottom coating comprises the following components in percentage by weight: 70%-80% of resin, 7%-9% of talcum powder, 2%-4% of aluminum oxide and 3%-10% of hydroxyethyl cellulose. The cooling anti-radiation coating formed by the synergistic cooperation of the components has high electromagnetic shielding performance and long service life.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a temperature-reducing and radiation-proof coating and a preparation method thereof. Background Art

[0002] The total ionizing dose effect produced by the space radiation environment is the main reason for the damage of satellite units and devices. The total ionizing radiation dose in space mainly comes from radiation belt electron radiation, solar high-energy proton radiation, and bremsstrahlung produced in the process of electron radiation.

[0003] Anti-radiation coatings have become a major topic in today's materials science. At present, anti-radiation coatings can be sprayed on substrates such as composite materials, engineering plastics, wood, cement surfaces, etc. to prevent or reduce the hazards caused by electromagnetic radiation (such as microwaves, visible light, ultraviolet light, etc.).

[0004] However, the radiation protection coatings in the prior art often have relatively poor radiation protection effects and are prone to absorb external infrared rays, causing the coating temperature to rise, further weakening the radiation protection function of the coating and easily causing the coating to fall off. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a temperature-reducing radiation-proof coating and a preparation method thereof, aiming to solve the technical problem that the existing radiation-proof coating has poor radiation effect due to easy absorption of external infrared rays.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides the following technical solutions: a temperature-reducing and radiation-proof coating, wherein the self-cleaning coating comprises a surface coating, an intermediate coating and a bottom coating;

[0008] The surface coating comprises the following components according to weight percentage: 40-60% polyethylene, 1%-5% carbon nanotubes, 1%-5% graphene oxide, 10%-15% dispersant, 5%-8% polyethylene glycol, 3%-8% nano barium oxide, and 3-10% nano boron nitride;

[0009] The intermediate coating comprises the following components according to weight percentage: 50%-70% polyurethane, 20%-30% silane coupling agent, and 5%-10% aluminum oxide;

[0010] The bottom coating layer comprises the following components according to weight percentage: 70%-80% of resin, 7%-9% of talc, 2%-4% of aluminum oxide, and 3%-10% of hydroxyethyl cellulose.

[0011] Furthermore, the nano-barium oxide and the aluminum oxide are both spherical, the particle size of the nano-barium oxide in the surface coating is 20-40 microns; the particle size of the aluminum oxide in the middle coating is 5-10 microns; and the particle size of the aluminum oxide in the bottom coating is 0.1-3 microns.

[0012] Furthermore, the resin in the base coating layer may be polyurethane resin or epoxy resin.

[0013] Furthermore, the carbon nanotubes are single-walled carbon nanotubes.

[0014] Furthermore, the liquid viscosity of the polyurethane is 200-1000 cps.

[0015] Furthermore, the barium oxide and the aluminum oxide are both spherical, the particle size of the barium oxide in the surface coating is 20-40 microns; the particle size of the aluminum oxide in the middle coating is 5-10 microns; and the particle size of the barium oxide in the bottom coating is 0.1-3 microns.

[0016] Furthermore, the coupling agent is any one of vinyltrimethoxyethoxysilane, γ-methacryloxypropyl, and trimethoxysilane.

[0017] A method for preparing the above-mentioned temperature-reducing and radiation-proof coating comprises the following steps:

[0018] S01: Resin, talcum powder, aluminum oxide, and hydroxyethyl cellulose are weighed and dissolved in ethanol according to the proportions, stirred evenly, and then sprayed on the substrate and cured for 8-12 hours to form a base coating;

[0019] S02: Weigh polyurethane, silane coupling agent, and aluminum oxide according to the ratio, mix them evenly, spray them on the base coating, and cure them for 8-12 hours to form an intermediate coating;

[0020] S03: polyethylene, carbon nanotubes, graphene oxide, dispersant, polyethylene glycol, nano-barium oxide and nano-boron nitride are weighed and dispersed in anhydrous ethanol by ultrasonic stirring according to the proportion; sprayed on the intermediate coating and cured for 9-18 hours to form a surface coating.

[0021] Furthermore, the step S03 includes:

[0022] A. Stirring graphene oxide, nano-boron nitride and polyethylene glycol at 60-80° C. for 3-5 hours to form a mixture M;

[0023] B. Adding nano-barium oxide, carbon nanotubes and dispersant to the mixture M, mixing and stirring for 3-6 hours to form a mixture N;

[0024] C. Add polyethylene solution to mixture N, stir evenly and set aside.

[0025] Furthermore, the substrate is any one of glass, photovoltaic panels and walls.

[0026] The beneficial effects of the present invention are as follows: compared with the prior art, the temperature-reducing and radiation-proof coating in the present invention has the following advantages:

[0027] (1) By adding talcum powder to the bottom coating, the linear expansion coefficient of the coating can be changed, the cold and hot alternating performance of the coating and the anti-cracking performance at high temperature can be improved, and the sedimentation of the coating during storage can be slowed down, and the coating can be prevented from sagging, thereby improving the water resistance and wear resistance of the coating; by adding hydroxyethyl cellulose, the aluminum oxide can be better and more firmly bonded to the resin, thereby increasing the service life of the coating;

[0028] (2) By using polyurethane and silane coupling agents with higher viscosity in the middle layer coating, the cross-linking density of the coating can be increased due to their effective combination with hydroxyethyl cellulose, thereby enhancing the bonding strength of each component and extending the service life of the coating;

[0029] (3) By adding alumina to the base coating and the middle coating, the high thermal conductivity and high density of alumina can help to conduct and dissipate heat in a timely manner, thereby achieving a cooling effect. On the other hand, it can improve the electromagnetic shielding performance of the coating and play a role in radiation protection.

[0030] (4) By using polyethylene glycol as the surface coating, graphene oxide can be modified, that is, polyethylene glycol is grafted onto graphene oxide. On the one hand, the interlayer spacing of graphene oxide can be extended, which helps to inhibit the aggregation of graphene oxide, and on the other hand, the compatibility of graphene oxide with polyethylene is improved; by adding a dispersant, nano-barium oxide and nano-boron nitride with high electromagnetic radiation resistance can be better dispersed between the interlayer spacing of graphene oxide. By using carbon nanotubes, the one-dimensional structure of carbon nanotubes gives it special electronic properties. The combined use of nano-metals and carbon nanotubes is beneficial to improving the electromagnetic shielding performance of the coating and playing a role in radiation protection.

[0031] Other advantages, objectives and features of the present invention will be described in the following description and will be apparent to those skilled in the art to some extent, or those skilled in the art may be taught from the practice of the present invention. The objectives and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration:

[0033] Figure 1 A flow chart of a method for preparing a temperature-reducing and radiation-proof coating according to an embodiment of the present invention;

[0034] Figure 2 A flowchart of step S03 is provided for one embodiment of the present invention. DETAILED DESCRIPTION

[0035] This embodiment provides a temperature reduction and radiation protection coating, including a surface coating, an intermediate coating and a bottom coating;

[0036] The surface coating comprises the following components according to weight percentage: 40-60% polyethylene, 1%-5% carbon nanotubes, 1%-5% graphene oxide, 10%-15% dispersant, 5%-8% polyethylene glycol, 3%-8% nano barium oxide, and 1-5% nano boron nitride;

[0037] The intermediate coating comprises the following components according to weight percentage: 50%-70% polyurethane, 20%-30% silane coupling agent, and 5%-10% aluminum oxide;

[0038] The bottom coating layer comprises the following components according to weight percentage: 70%-80% of resin, 7%-9% of talc, 2%-4% of aluminum oxide, and 3%-10% of hydroxyethyl cellulose.

[0039] In the present application, by adding talcum powder to the bottom coating, the linear expansion coefficient of the coating can be changed, the hot and cold alternating performance and the anti-cracking performance at high temperature of the coating can be improved, and the sedimentation of the coating during storage can be slowed down, and the coating can be prevented from sagging, thereby improving the water resistance and wear resistance of the coating; by adding hydroxyethyl cellulose, the aluminum oxide can be better and more firmly bonded to the resin, thereby improving the service life of the coating; by using polyurethane and silane coupling agents with higher viscosity in the middle coating, the cross-linking density of the coating can be increased due to the effective combination with hydroxyethyl cellulose, the bonding strength of each component can be enhanced, and the service life of the coating can be extended; by adding aluminum oxide to the bottom coating and the middle coating, the high thermal conductivity and high density of aluminum oxide can be used to transfer heat in time. On the one hand, the heat is conducted away to have a cooling effect, and on the other hand, the electromagnetic shielding performance of the coating is improved to play a role in radiation protection; by adding polyethylene glycol to the surface coating, the graphene oxide can be modified, that is, the polyethylene glycol is grafted onto the graphene oxide, on the one hand, the interlayer spacing of the graphene oxide can be extended, which helps to inhibit the aggregation of the graphene oxide, and on the other hand, the compatibility of the graphene oxide with polyethylene is improved; by adding a dispersant, the nano-barium oxide and nano-boron nitride with high electromagnetic radiation resistance can be better dispersed between the interlayer spacing of the graphene oxide, and the carbon nanotubes are used because the one-dimensional structure of the carbon nanotubes gives it special electronic properties. The combined use of nano-metals and carbon nanotubes is beneficial to improving the electromagnetic shielding performance of the coating and playing a role in radiation protection.

[0040] Preferably, the thickness of the bottom coating is 0.01mm to 0.3mm; the thickness of the middle coating is 0.05mm to 0.3mm; the thickness of the surface coating is 0.05mm to 0.5mm. Specifically, the thickness of the bottom coating can be 0.01mm, 0.1mm, 0.15mm, 0.20mm, 0.25mm, 0.30mm, etc.; the thickness of the middle coating is 0.05mm, 0.1mm, 0.15mm, 0.20mm, 0.25mm, 0.30mm, etc.; the thickness of the surface coating is 0.05mm, 0.1mm, 0.15mm, 0.20mm, 0.25mm, 0.30mm, 0.4mm, 0.5mm, etc. According to the actual situation and specific needs, coatings of different thicknesses can be matched so that the coating has a certain toughness. Of course, in this embodiment, according to the actual situation and specific needs, the thickness of each of the above coatings can also be set to other values, which are not limited here.

[0041] Preferably, the resin in the base coating is polyurethane resin or epoxy resin.

[0042] Preferably, the carbon nanotube is a single-walled carbon nanotube. In this way, the one-dimensional wall structure of the carbon nanotube gives it special electronic properties, and the combined use of nanometal and carbon nanotube is conducive to improving the electromagnetic shielding performance of the coating and playing a role in radiation protection.

[0043] Preferably, the liquid viscosity of the polyurethane is 200-1000cps. Specifically, the liquid viscosity may be 200cps, 300cps, 400cps, 500cps, 600cps, 700cps, 800cps, 900cps, 1000cps, etc. In the present application, the liquid viscosity of the polyurethane is preferably 800cps, which has the best compatibility with the above components and is easy to adjust the hydrophobicity.

[0044] Preferably, the nano-barium oxide and aluminum oxide are both spherical, the particle size of the nano-barium oxide in the surface coating is 20-40 microns; the particle size of the aluminum oxide in the intermediate coating is 5-10 microns; the particle size of the aluminum oxide in the bottom coating is 0.1-3 microns; specifically, the particle size of the nano-barium oxide is 20 microns, 24 microns, 26 microns, 28 microns, 30 microns, 32 microns, 34 microns, 36 microns; the particle size of the aluminum oxide in the intermediate coating is 5 microns, 6 microns, 7 microns, 8 microns, 9 microns, 10 microns; the particle size of the aluminum oxide in the bottom coating is 0.1 micron, 0.5 micron, 1.0 micron, 1.5 microns, 2.0 microns, 2.5 microns, 3.0 microns, etc. By mixing metal oxides of different types and particle sizes, a rich heat-conducting network chain is formed, thereby achieving a better heat dissipation effect.

[0045] Preferably, the silane coupling agent is at least one of γ-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane and γ-methacryloxypropyltrimethoxysilane.

[0046] Table 1 Examples 1-6 show the composition ratios in the surface coating

[0047]

[0048] In the present application, the components of the bottom coating and the middle coating are kept unchanged, the components of the surface coating are adjusted, and the coatings prepared in Examples 1-6 are tested according to the standard of SJ20524-1995 to test their absorbing performance (dB, used to measure their electromagnetic shielding effect) at 30MHz-5GHz. The results are shown in Table 2:

[0049] Table 2 Performance test results shown in Examples 1-6

[0050]

[0051] According to the performance test table of Examples 1-6 in Table 2 above, it can be seen that in the present invention, by comparing Example 1 with Example 2, it can be seen that with the increase of the content of carbon nanotubes, the absorbing performance effect is increased, which is due to the increase of the content of carbon nanotubes; by comparing and analyzing Example 4, Example 5, and Example 6, it can be seen that with the increase of the content of nano-barium oxide, the absorbing performance effect is increased, which is due to the increase of the content of nano-barium oxide with high corrosion resistance.

[0052] In this application, please refer to Figure 1 As shown, a method for preparing a temperature-reducing and radiation-proof coating is also disclosed, comprising the following steps:

[0053] S01: Resin, talcum powder, aluminum oxide, and hydroxyethyl cellulose are weighed and dissolved in ethanol according to the proportions, stirred evenly, and then sprayed on the substrate and cured for 8-12 hours to form a base coating;

[0054] S02: Weigh polyurethane, silane coupling agent, and aluminum oxide according to the ratio, mix them evenly, spray them on the base coating, and cure them for 8-12 hours to form an intermediate coating;

[0055] S03: polyethylene, carbon nanotubes, graphene oxide, dispersant, polyethylene glycol, nano-barium oxide and nano-boron nitride are weighed and dispersed in anhydrous ethanol by ultrasonic stirring according to the proportion; sprayed on the intermediate coating and cured for 9-18 hours to form a surface coating.

[0056] In the present application, by stacking and cooperating the above-mentioned coatings, the obtained temperature-reducing and radiation-proof coating has higher radiation resistance and higher thermal conductivity.

[0057] Preferably, see Figure 2 As shown, step S03 includes:

[0058] A. Stirring graphene oxide, nano-boron nitride and polyethylene glycol at 60-80° C. for 3-5 hours to form a mixture M;

[0059] B. Adding nano-barium oxide, carbon nanotubes and dispersant to the mixture M, mixing and stirring for 3-6 hours to form a mixture N;

[0060] C. Add polyethylene solution to mixture N, stir evenly and set aside.

[0061] In the present application, firstly, graphene oxide, nano-boron nitride and polyethylene glycol are stirred at 60-80°C, and polyethylene glycol can be well grafted onto graphene oxide to form polyethylene glycol-modified graphene oxide, which helps to inhibit the aggregation of graphene oxide; in addition, boron nitride is inserted between the interlayer spacing of graphene oxide to form a stable three-dimensional network thermal conductive structure, thereby improving the thermal conductivity of the coating; then, nano-barium oxide, carbon nanotubes and dispersants are added to make the one-dimensional carbon nanotubes and nano-barium oxide uniformly dispersed in the three-dimensional network structure in the graphene oxide, so that the surface coating has higher radiation resistance.

[0062] Preferably, the substrate is any one of glass, photovoltaic panels, and walls. Of course, in the present application, the substrate can also be set to other types, which are not limited here.

[0063] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A cooling and radiation-proof coating, characterized in that: The radiation protection coating comprises a surface coating, an intermediate coating and a bottom coating; The surface coating comprises the following components according to weight percentage: 40-60% polyethylene, 1%-5% carbon nanotubes, 1%-5% graphene oxide, 10%-15% dispersant, 5%-8% polyethylene glycol, 3%-8% nano barium oxide, and 3-10% nano boron nitride; The intermediate coating comprises the following components according to weight percentage: 50%-70% polyurethane, 20%-30% silane coupling agent, and 5%-10% aluminum oxide; The bottom coating layer comprises the following components according to weight percentage: 70%-80% of resin, 7%-9% of talc, 2%-4% of aluminum oxide, and 3%-10% of hydroxyethyl cellulose.

2. A temperature-reducing and radiation-proof coating according to claim 1, characterized in that: The thickness of the bottom coating is 0.01 mm to 0.3 mm; the thickness of the middle coating is 0.05 mm to 0.3 mm; and the thickness of the surface coating is 0.05 mm to 0.5 mm.

3. The temperature-reducing and radiation-proof coating according to claim 1, characterized in that: The resin in the base coating layer may be a polyurethane resin or an epoxy resin.

4. The temperature-reducing and radiation-proof coating according to claim 1, characterized in that: The carbon nanotubes are single-walled carbon nanotubes.

5. The temperature-reducing and radiation-proof coating according to claim 1, characterized in that: The liquid viscosity of the polyurethane is 200-1000 cps.

6. The temperature-reducing and radiation-proof coating according to claim 1, characterized in that: The nano-barium oxide and the aluminum oxide are both spherical, the particle size of the nano-barium oxide in the surface coating is 20-40 microns; the particle size of the aluminum oxide in the middle coating is 5-10 microns; the particle size of the aluminum oxide in the bottom coating is 0.1-3 microns.

7. The temperature-reducing and radiation-proof coating according to claim 1, characterized in that: The coupling agent is any one of vinyl trimethoxyethoxysilane, γ-methacryloxypropyl and trimethoxysilane.

8. A method for preparing the temperature-reducing and radiation-proof coating according to any one of claims 1 to 7, characterized in that: The steps include: S01: Resin, talcum powder, aluminum oxide, and hydroxyethyl cellulose are weighed and dissolved in ethanol according to the proportions, stirred evenly, and then sprayed on the substrate and cured for 8-12 hours to form a base coating; S02: Weigh polyurethane, silane coupling agent, and aluminum oxide according to the ratio, mix them evenly, spray them on the base coating, and cure them for 8-12 hours to form an intermediate coating; S03: polyethylene, carbon nanotubes, graphene oxide, dispersant, polyethylene glycol, nano-barium oxide, and nano-boron nitride are weighed and dispersed in anhydrous ethanol by ultrasonic stirring according to the ratio; Spray on the middle coating and cure for 9-18 hours to form the surface coating.

9. The method for preparing a temperature-reducing and radiation-proof coating according to claim 8, characterized in that: The step S03 comprises: A. Stirring graphene oxide, nano-boron nitride and polyethylene glycol at 60-80° C. for 3-5 hours to form a mixture M; B. Adding nano-barium oxide, carbon nanotubes and dispersant to the mixture M, mixing and stirring for 3-6 hours to form a mixture N; C. Add polyethylene solution to mixture N, stir evenly and set aside.

10. The method for preparing a temperature-reducing and radiation-proof coating according to claim 8, characterized in that: The substrate is any one of glass, photovoltaic panels and walls.

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