Coatings for Integrated Space Proton Radiation Protection and Thermal Control and Their Preparation Method

Abstract

This invention provides a coating for integrated proton radiation protection and thermal control in space and its preparation method. The coating comprises the following components in parts by weight: 1 to 100 parts of a coating binder resin; 10 to 60 parts of surface-grown CNT metal particles; the CNTs covering the metal have a coating rate greater than 90%. The preparation method includes dissolving the coating binder resin in an organic solvent and diluting it to 20-25% wt, adding the surface-grown CNT metal particles, and mixing and stirring evenly to obtain the coating. The coating is sprayed onto the surface of a substrate and cured at 100℃-150℃ for 12-36 hours to obtain an integrated radiation protection and thermal control coating. This invention solves the problems of low protection efficiency of existing radiation protection metal materials, conflicts with thermal control systems during use, and complex coating processes.

Description

Technical Field

[0001] This invention relates to the field of aerospace technology, specifically to coatings for integrated space proton radiation protection and thermal control, their preparation methods, and applications. Background Technology

[0002] Spacecraft operating in orbit are exposed to the Earth's radiation belts, resulting in a total dose effect (TND). This TND can severely damage satellite electronic components. When a spacecraft enters the Earth's inner radiation belt region, protons play a dominant role in contributing to the TND. Some satellites employ the same protection design used in high-orbit satellites, incorporating high atomic number metals (tantalum, lead, etc.) for physical shielding. However, this shielding method suffers from complex manufacturing processes, poor compatibility with components, and poor proton protection against heavy elements. While thickening the aluminum shell to improve the TND resistance of components increases weight, it does not meet the lightweight design requirements of spacecraft.

[0003] Besides metals, existing shielding materials also include thin film materials based on polyethylene doped with metal powders and nanomaterials. These are used for satellite cabin exteriors, single-unit casing exteriors, and device exterior coatings. However, due to limitations in their substrate materials and coating methods, these materials result in poor device heat dissipation, causing conflicts with the satellite's thermal control system. Summary of the Invention

[0004] The present invention aims to solve the problems of low protection efficiency of existing radiation protection metal materials, conflicts between radiation protection composite film materials and thermal control systems during use, and complex construction processes of coating, and provides a coating for integrated space proton radiation protection and thermal control and its preparation method.

[0005] The technical solution provided by this invention is as follows:

[0006] A coating for integrated space proton radiation protection and thermal control, the coating comprising the following components in parts by weight:

[0007] Coating adhesive resin: 1 part to 100 parts;

[0008] 10 to 60 parts of metal particles on which CNTs are grown on the surface;

[0009] The surface is covered with CNTs metal particles, and the CNTs have a Cu coating rate of more than 90%.

[0010] In one embodiment of the present invention, the coating comprises the following components in parts by weight:

[0011] 10 to 90 parts of coating adhesive resin;

[0012] 20 to 50 parts of metal particles on which CNTs are grown on the surface;

[0013] The surface is covered with metal particles containing CNTs, and the CNTs have a metal coating rate of more than 90%.

[0014] In one embodiment of the present invention, the coating comprises the following components in parts by weight:

[0015] 50 to 70 parts of coating adhesive resin;

[0016] 30 to 40 parts of metal particles on which CNTs are grown on the surface;

[0017] The surface is covered with metal particles containing CNTs, and the CNTs have a metal coating rate of more than 90%.

[0018] The metal particles in which CNTs are grown on the surface are Cu particles.

[0019] The method for preparing Cu particles with CNTs grown on the surface includes the following steps:

[0020] Step 1: Use ferric nitrate solution as a precursor solution to impregnate Cu particles to form Cu particles with a supported catalyst precursor. Dry the Cu particles to obtain Cu particles with Fe dispersed on the surface.

[0021] Step 2: Place Cu particles with Fe dispersed on the surface into a reactor, introduce an inert gas to purge the air, then introduce H2 as a carrier gas, heat to 750℃~1000℃, introduce C2H2 as a carbon source, and start the growth of carbon nanotubes. The growth time is 30-80 min, and Cu particles with CNTs grown on the surface are obtained.

[0022] In step 2, the H2 flow rate is 60 sccm-80 sccm; the C2H2 flow rate is 100 sccm-120 sccm.

[0023] In step 2, the reactor is a tubular furnace.

[0024] The coating adhesive resin includes at least one of epoxy resin, silicone resin, and polysilazane resin.

[0025] This invention also provides a method for preparing a coating for integrated space proton radiation protection and thermal control, comprising the following steps:

[0026] The coating adhesive resin is dissolved in an organic solvent and diluted to 20-25%wt. Metal particles with CNTs grown on the surface are added and mixed evenly to obtain the coating for integrated space proton radiation protection and thermal control.

[0027] The organic solvent is xylene.

[0028] This invention also provides an integrated radiation protection and thermal control coating, which is prepared by a method comprising the following steps:

[0029] The coating for integrated space proton radiation protection and thermal control is sprayed onto the surface of a substrate and cured at 100℃~150℃ for 12~36h to obtain the integrated radiation protection and thermal control coating.

[0030] CNTs have a metal coating rate of more than 90%, which can effectively improve the thermal conductivity of metal particles. CNTs on the metal surface can form thermal conductive links in the resin matrix. Compared with single metal particles, metal particles coated with CNTs form line connections between CNTs when forming thermal conductive links, instead of point connections between metal particles. At the same time, CNTs in the matrix material can utilize the high proton blocking ability of carbon to improve the absorption capacity of protons.

[0031] The coating adhesive resin includes E51 epoxy resin, vinyl MQ silicone resin, vinyl polysilazane resin, etc.

[0032] The present invention also provides an application of a coating for integrated space proton radiation protection and thermal control, which replaces the high-emissivity black paint inside the satellite cabin while protecting the satellite from space proton radiation.

[0033] The coating provided by this invention is applied by spraying, which is easier to implement than metal shielding materials, composite protective films, etc.

[0034] The present invention has the following advantages:

[0035] 1. The coating provided by the present invention is easier to implement than metal shielding materials, composite protective films, etc., because it adopts the coating spraying method, thus expanding its scope of application.

[0036] 2. The coating provided by the present invention uses metal particles with CNTs grown on the surface during the coating preparation process, which can effectively improve the thermal conductivity of the coating and has a high hemispherical emissivity. When used for satellite radiation protection, it is beneficial to the heat conduction of the device and the radiation of heat in a vacuum environment.

[0037] 3. The coating provided by this invention improves the proton protection efficiency by 1.14 to 1.94 times compared to pure aluminum (with the same mass and thickness);

[0038] 4. The coating provided by this invention has a thermal conductivity of 0.21 W / m·K to 0.87 W / m·K and a hemispherical emissivity of 0.85 to 0.90. Attached Figure Description

[0039] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0040] Figure 1 This is a schematic diagram of a coating structure used for integrated proton radiation protection and thermal control in space. Detailed Implementation

[0041] The present invention will be described in detail below with reference to embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several adjustments and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0042] In this invention:

[0043] E51 epoxy resin: Shanghai Resin Factory Co., Ltd.;

[0044] Addition-type MQ silicone resin: Zhejiang Silicon Innovation Technology Co., Ltd.;

[0045] Vinyl polysilazane resin: Anhui Aiyota Silicon Oil Co., Ltd.

[0046] Preparation of Metal (Cu, Fe, Ta, or Pt) Particles with Surface-Grown CNTs (Example 1): The preparation method of metal (Cu, Fe, Ta, or Pt) particles with surface-grown CNTs is as follows:

[0047] S1. Using 0.1 mol / L ferric nitrate as a precursor solution, impregnate metal (Cu or Fe or Ta or Pt) particles for 30 min to form (Cu or Fe or Ta or Pt) particles of supported catalyst precursor, and then dry at 100 °C to obtain metal (Cu or Fe or Ta or Pt) particles with uniformly dispersed Fe on the surface.

[0048] S2. Transfer the dispersed Fe metal (Cu, Fe, Ta, or Pt) particles to a tube furnace. First, purge with an inert gas for 5 minutes, then purge with 60 sccm of H2 as a carrier gas. Heat to 800℃ (750℃~1000℃), then purge with 120 sccm of C2H2 as a carbon source. Start the growth of carbon nanotubes at high temperature. After the growth is complete, turn off H2 and C2H2. After the system is cooled to room temperature under an inert gas, remove the sample from the device to obtain the metal (Cu, Fe, Ta, or Pt) particles with CNTs grown on the surface.

[0049] After 30 min of growth, surface-grown CNTs with a 50% coating rate of Cu, Fe, Ta, or Pt were obtained.

[0050] After 80 min of growth, metal (Cu, Fe, Ta, or Pt) particles with CNTs covering Cu were obtained on the surface.

[0051] Examples 1-5

[0052] Examples 1-5 relate to a coating for integrated space proton radiation protection and thermal control, and its preparation method. The coating components and dosages of Examples 1-5 are shown in Table 1.

[0053] Table 1. Components and dosages of the coatings described in Examples 1-5 (unit: parts by weight)

[0054]

[0055] 2. The preparation method of the coating for integrated space proton radiation protection and thermal control described in Examples 1-5 includes the following steps:

[0056] S1. Weigh out the coating adhesive resin, the metal particles with CNTs grown on the surface, and xylene for later use;

[0057] S2. Dissolve the coating adhesive resin in xylene, add the metal particles with CNTs grown on the surface to the coating adhesive resin solution, mix and stir until the coating is uniform.

[0058] S3. Spray the prepared coating onto the substrate surface. Refer to Table 1 for curing conditions to obtain an integrated radiation protection and thermal control coating.

[0059] Schematic diagrams of the coating structures in Examples 1-5 are shown below. Figure 1 Cu particles with CNTs grown on their surface are uniformly distributed within the resin binder, forming a stable integrated coating for proton radiation protection and thermal control. When protons are incident, they interact with the coating, binder, and particles, losing energy through collisions and absorption, achieving highly efficient energy loss and absorption of incident protons. The core-shell interface and the interface formed between the core and the binder can further absorb secondary particles. Simultaneously, the surface CNTs between the particles interconnect, forming thermal conductive pathways, which are more efficient than those formed by spherical Cu particles, thus improving the thermal conductivity of the coating.

[0060] Comparative Example 1

[0061] The difference between Comparative Example 1 and Example 2 is that the Cu particles with surface-grown CNTs are replaced with Fe particles with surface-grown CNTs.

[0062] Comparative Example 2

[0063] The difference between Comparative Example 1 and Example 2 is that the Cu particles with surface-grown CNTs are replaced with Ta particles with surface-grown CNTs.

[0064] Comparative Example 3

[0065] The difference between Comparative Example 1 and Example 2 is that the Cu particles with surface-grown CNTs are replaced with Pt particles with surface-grown CNTs.

[0066] Comparative Example 4

[0067] The difference between Comparative Example 4 and Example 2 is that the CNTs have a Cu coating rate of 50%.

[0068] Table 2 shows the components and amounts of the compositions described in Comparative Example 1 (unit: parts by weight).

[0069]

[0070]

[0071] Performance Test Example 1

[0072] The coatings prepared in Examples 1-5 and Comparative Examples 1-4, as well as existing pure aluminum (control group), were subjected to proton irradiation protection tests.

[0073] 1. Test method:

[0074] Proton irradiation protection performance testing method: A 10 MeV monoenergetic proton beam is generated using a particle accelerator to irradiate the sample. Since the proton energy diverges after penetrating the sample, a proton energy detector is used to record the energy value of the protons after passing through the sample, ultimately forming a transmission energy spectrum. The energy value E corresponding to the peak value of the transmission energy spectrum is selected. p The energy of the transmitted proton is characterized by (which is also the average energy of the transmitted proton), where E0 is the energy of the monoenergetic proton used. The proton protection efficiency η of the sample under approximate energy spectrum incident light is calculated by the following formula. p ,unit"%":

[0075]

[0076] 2. Test Results:

[0077] Table 3 shows the comparison results of the proton protection efficiency of radiation protection materials S1~S4 and D1~4 with pure aluminum at the same mass and thickness.

[0078] Table 3 shows that, for the same mass thickness, the proton protection efficiency of radiation protection material S2 is 1.94 times that of pure aluminum (the protection efficiency of radiation protection material I or pure aluminum is plotted with protection efficiency as the vertical axis and mass thickness as the horizontal axis).

[0079] Performance Test Example 2

[0080] For the coatings prepared in Examples 1-5 and Comparative Example 1, the specific heat capacity c was measured according to the standard test method of ASTM E1269 using differential scanning calorimetry to determine the specific heat capacity, and the thermal diffusivity α was measured according to the standard test method of ASTM E1461 using the flash method to determine the thermal diffusivity. The thermal conductivity λ was calculated using the formula λ=αρc. The test results are shown in Table 3.

[0081] Performance Test Example 3

[0082] The coatings prepared in Examples 1-5 and Comparative Example 1 were subjected to hemispherical emissivity ε testing according to standard GJB2502.3-2015 Test Methods for Thermal Control Coatings for Spacecraft Part 3: Emissivity Testing. H The test results are shown in Table 3.

[0083] Table 3 compares the protective efficiency, thermal conductivity, and hemispherical emissivity of the examples and comparative examples with those of pure aluminum.

[0084]

[0085] This invention discloses a coating for integrated space proton radiation protection and thermal control. Because it employs a coating spraying method, it is easier to implement than metal shielding materials and composite protective films, thus expanding its application range. Simultaneously, CNTs in the matrix material utilize the high proton-blocking ability of carbon, improving proton absorption. The use of Cu particles with surface-grown CNTs effectively improves the coating's thermal conductivity, enhancing the heat transfer effect of the device. The addition of surface-grown CNTs Cu particles gives the coating a high hemispherical emissivity, improving radiation performance in a vacuum environment. The coating provided by this invention uses epoxy resin as a binder and surface-grown CNTs Cu particles as a filler. Its purpose is to solve the problems of low protection efficiency of existing radiation protection metal materials, conflicts between radiation protection composite film materials and thermal control systems during use, and the complex construction process of the coating. The coating is used for protection against space proton radiation. This invention is applicable to the field of radiation protection.

[0086] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A coating for integrated space proton radiation protection and thermal control, characterized in that, The coating comprises the following components in parts by weight: Coating adhesive resin: 1 part to 100 parts; 10 to 60 parts of metal particles on which CNTs are grown on the surface; The metal particles on the surface with CNTs grown have a metal coating rate of greater than 90%. The metal particles in which CNTs are grown on the surface are Cu particles in which CNTs are grown on the surface. The method for preparing Cu particles with CNTs grown on the surface includes the following steps: Step 1: Use ferric nitrate solution as a precursor solution to impregnate Cu particles to form Cu particles with a supported catalyst precursor. Dry the Cu particles to obtain Cu particles with Fe dispersed on the surface. Step 2: Place Cu particles with Fe dispersed on the surface into a reactor, introduce an inert gas to purge the air, then introduce H2 as a carrier gas, heat to 750℃~1000℃, introduce C2H2 as a carbon source, and start the growth of carbon nanotubes. The growth time is 30-80 min, and Cu particles with CNTs grown on the surface are obtained.

2. The coating according to claim 1, characterized in that, The coating comprises the following components in parts by weight: 10 to 90 parts of coating adhesive resin; 20 to 50 parts of metal particles on which CNTs are grown on the surface.

3. The coating according to claim 1, characterized in that, The coating comprises the following components in parts by weight: 50 to 70 parts of coating adhesive resin; 30 to 40 parts of metal particles on which CNTs are grown on the surface.

4. The coating according to claim 1, characterized in that, In step 2, the H2 flow rate is 60-80 sccm; the C2H2 flow rate is 100-120 sccm.

5. The coating according to claim 1, characterized in that, The coating adhesive resin includes at least one of epoxy resin, silicone resin, and polysilazane resin.

6. A method for preparing a coating for integrated space proton radiation protection and thermal control as described in any one of claims 1-5, characterized in that, Includes the following steps: The coating adhesive resin is dissolved in an organic solvent and diluted to 20-25%wt. Metal particles with CNTs grown on the surface are added and mixed evenly to obtain the coating for integrated space proton radiation protection and thermal control.

7. A coating integrating radiation protection and thermal control, characterized in that, The integrated radiation protection and thermal control coating is prepared by a method comprising the following steps: The coating for integrated space proton radiation protection and thermal control described in any one of claims 1-5 is sprayed onto the surface of a substrate and cured at 100℃~150℃ for 12~36h to obtain the integrated radiation protection and thermal control coating.

8. The application of a coating for integrated space proton radiation protection and thermal control as described in any one of claims 1-5, characterized in that, This coating can be used to protect satellites from space proton radiation while replacing the high-emissivity black paint inside the satellite cabin.

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