Super-hydrophobic surface modified antenna housing with long life cycle and preparation method thereof

Abstract

The invention belongs to the technical field of communication equipment protection, and particularly relates to a long-life-cycle super-hydrophobic surface modified antenna housing and a preparation method thereof.The surface modified antenna housing comprises an antenna housing body and a functional coating coated on the surface of the antenna housing, and the functional coating comprises a surface layer and a bottom layer directly coated on the antenna housing body from top to bottom; wherein the surface layer is prepared from the following raw materials in parts by weight: 60 to 80 parts of matrix resin, 5 to 8 parts of a nano reinforcing agent, 3 to 8 parts of a cross-linking agent, 30 to 35 parts of organic silicon resin, 0.5 to 1 part of a light stabilizer, 0.3 to 0.5 part of an antioxidant and 120 to 150 parts of a solvent. The surface modified antenna housing prepared by the method has a super-hydrophobic surface and a relatively long service life.

Description

Technical Field

[0001] This invention belongs to the field of communication equipment protection technology, specifically relating to a long-life, superhydrophobic surface-modified radome and its preparation method. Background Technology

[0002] A radome is a protective device used to shield antennas from the effects of the natural environment, and it is widely used in communications, radar, and other fields. However, existing radomes, when exposed to harsh environments such as rain, salt spray, and ultraviolet radiation for extended periods, are susceptible to corrosion, leading to a decline in their surface performance and affecting the antenna's signal transmission. Furthermore, ordinary radomes have a limited lifespan, requiring frequent replacement and increasing maintenance costs. Therefore, to extend the lifespan of radomes, surface modification treatments are often necessary.

[0003] For example, patent CN110387191B discloses a hydrophobic coating and its preparation method, as well as a hydrophobic coating solution, which solves the problems of poor high-temperature resistance and cumbersome preparation process of existing hydrophobic coatings. The raw materials for preparing this hydrophobic coating include polysiloxane. The hydrophobic coating solution was prepared using a perhydrohydropolysilazane hybrid polymer; the composition by mass percentage of the solution was: polysiloxane. The hydrophobic coating consists of 1%-50% all-hydrogen polysilazane hybrid polymer; 50%-90% solvent; 0-5% catalyst; and 0-20% additives. The method for preparing the hydrophobic coating involves coating the substrate surface with the hydrophobic coating solution and then curing it. This hydrophobic coating solution can be used in aerospace, electronics, and electrical appliance fields.

[0004] Patent CN112778885B discloses a superhydrophobic coating material and its preparation method, as well as a superhydrophobic coating. The superhydrophobic coating material comprises surface-modified basic magnesium sulfate whiskers. The preparation method includes: providing basic magnesium sulfate whiskers; obtaining surface-modified basic magnesium sulfate whiskers through a surface modification process; providing a binder; and mixing the surface-modified basic magnesium sulfate whiskers and the binder in a predetermined mass ratio to obtain the superhydrophobic coating material. This invention also provides a superhydrophobic coating by mixing the above-mentioned superhydrophobic coating material with a diluent to obtain a slurry, and then preparing the superhydrophobic coating from the slurry through a coating process.

[0005] While the hydrophobic coatings obtained by the above patents improve hydrophobicity to some extent, they do not take into account long-term performance such as corrosion resistance and resistance to damp heat aging, which affects the service life of the radome. Therefore, there is an urgent need in the market for a radome with a long service life and a hydrophobic surface. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention provides a long-lifetime, superhydrophobic surface-modified radome and its preparation method. The surface-modified radome prepared by the present invention has good hydrophobicity and aging resistance, and the coating has high adhesion to the substrate.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The first aspect of this invention provides a long-lifetime, superhydrophobic surface-modified radome, comprising a radome body and a functional coating applied to the surface of the radome. The functional coating consists of a top layer and a bottom layer directly applied to the radome body, from top to bottom. The raw materials for preparing the top layer, by weight, include the following: 60-80 parts of matrix resin, 5-8 parts of nano-reinforcing agent, 3-8 parts of crosslinking agent, 30-35 parts of silicone resin, 0.5-1 part of light stabilizer, 0.3-0.5 parts of antioxidant, and 120-150 parts of solvent.

[0008] In some embodiments, the method for preparing the matrix resin includes the following steps: (1) Perfluorosaturated sebacic acid, pentaerythritol triacrylate, and sulfuric acid were added to DMF and reacted at 70-80℃ for 7-8 hours. The mixture was then washed and dried to obtain the compound. (2) Methyl methacrylate, the compound obtained in step (1), N-methyl-5-hexene-1-amine and the initiator were added to chloroform and reacted at 60-65℃ for 1.5-2.5h. After drying, the polymer was obtained. (3) Under nitrogen protection, the polymer obtained in step (2) and chloromethyltrimethylsilane were added to dichloromethane, heated to 40-50℃, and pyridine was added to react for 11-13h. The mixture was then washed, distilled, and dried to obtain the matrix resin.

[0009] Conventional fluorocarbon resins and silanes are usually physically blended, which is prone to phase separation and leads to a shortened service life of the radome. This invention reacts perfluorosepiacetic acid with pentaerythritol triacrylate to obtain a compound, which is then polymerized with various monomers to obtain a polymer, and further reacted with silane to obtain a resin as the matrix resin. This resin not only maintains good hydrophobicity but also ensures the interfacial adhesion of the coating, preventing cracking under extreme conditions and enhancing the radome's performance. This is likely because low surface energy fluorinated segments are directly embedded into the resin backbone rather than through simple physical mixing, ensuring the durability of hydrophobicity. In addition, the introduction of flexible segments such as methyl methacrylate and N-methyl-5-hexene-1-amine, and the limitation of the ratio between each monomer, avoids the problem of excessive rigidity of the perfluorinated segments and reduced coating adhesion. Furthermore, the perfluorinated segments are covalently bonded to silane groups through chemical reaction to achieve uniform molecular-level hybridization, while also exhibiting good compatibility with nano-reinforcers, forming an organic-inorganic covalent interface, solving the problem of easy agglomeration of nanoparticles in traditional coatings.

[0010] In some embodiments, the mass ratio of perfluorosedioic acid to pentaerythritol triacrylate in step (1) is (0.5-0.9):1.

[0011] In some embodiments, the mass ratio of methyl methacrylate to the compound in step (2) is 1:(0.5-2).

[0012] In some embodiments, the mass ratio of the polymer to chloromethyltrimethylsilane in step (3) is 1:(0.2-0.6).

[0013] In some embodiments, the nano-reinforcing agent is nano-titanium dioxide.

[0014] In some embodiments, the crosslinking agent is tridecafluorooctyltriethoxysilane.

[0015] In some embodiments, the silicone resin is a methylphenyl silicone resin.

[0016] In some embodiments, the raw material for preparing the substrate is a silane coupling agent solution.

[0017] Preferably, the silane coupling agent is γ-glycidoxypropyltrimethoxysilane.

[0018] A second aspect of this invention provides a method for fabricating a long-lifetime, superhydrophobic surface-modified radome, comprising the following steps: S1. Stir the matrix resin, nano-reinforcing agent, crosslinking agent, organosilicon resin, light stabilizer, antioxidant, and solvent at 50-60℃ for 50-70 minutes to obtain the surface solution. S2. Apply the base material to the radome with a coating thickness of 0.1-0.3 mm and dry it at 40-50℃ for 6-8 hours to obtain the base layer. Then, apply the surface solution to the obtained base layer with a coating thickness of 0.3-0.5 mm and cure it at 40-60℃ for 6-8 hours. Finally, cure it at 100-120℃ for 2-3 hours to obtain the surface-modified radome.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention obtains a long-lifetime, superhydrophobic surface-modified radome by coating a functional coating on the radome body. The coating has high adhesion to the radome body, and is also superhydrophobic and resistant to aging.

[0020] 2. This invention obtains a compound by reacting perfluorosepiacetic acid with pentaerythritol triacrylate, then polymerizes the compound with various monomers to obtain a polymer, and further reacts it with silane to obtain a resin as the matrix resin, which gives the coating good hydrophobicity and ensures the interfacial bonding of the coating. This solves the problem that conventional fluorocarbon resins and silanes are usually physically blended, which easily leads to phase separation and reduces the service life of the radome.

[0021] 3. This invention avoids the problem of excessive rigidity of perfluorinated segments and decreased coating adhesion by introducing flexible segments such as methyl methacrylate and N-methyl-5-hexene-1-amine and limiting the ratio between each monomer. At the same time, it can have good compatibility with nano-reinforcers to form an organic-inorganic covalent interface, thus solving the problem of easy agglomeration of nanoparticles in traditional coatings. Detailed Implementation

[0022] The present invention will be described below with reference to specific embodiments. It should be noted that the examples and comparative examples below are for illustrative purposes only and are not intended to limit the invention. Other combinations and various modifications within the scope of the invention can be made without departing from its spirit or scope.

[0023] To facilitate the implementation of this invention by those skilled in the art, the following description is provided regarding some of the raw materials and manufacturers in the embodiments and comparative examples: Methylphenyl silicone resin was purchased from Luoyang Yiyuan New Material Co., Ltd., grade SH9802; the nano titanium dioxide particle size was 20nm. The compounds and related reagents used in the other examples and comparative examples are all commercially available.

[0024] Preparation Example 1 The preparation method of matrix resin-1 includes the following steps: (1) 8g of perfluorosedioic acid, 10g of pentaerythritol triacrylate, and 4ml of 85wt% sulfuric acid were added to 200ml of DMF and reacted at 75℃ for 7.5h. The mixture was then washed and dried to obtain the compound. (2) Add 10g of methyl methacrylate, 17g of the compound obtained in step (1), 5g of N-methyl-5-hexene-1-amine and 0.3g of azobisisobutyronitrile to 100ml of chloroform, react at 63℃ for 2h, and dry to obtain the polymer; (3) Under nitrogen protection, 10g of the polymer obtained in step (2) and 4g of chloromethyltrimethylsilane were added to 80ml of dichloromethane, heated to 45℃, and 0.2g of pyridine were added to react for 11-13h. The mixture was washed, distilled, and dried to obtain matrix resin-1.

[0025] Preparation Example 2 The preparation method of matrix resin-2 is the same as that of preparation example 1, except that the amount of perfluorosepiacetic acid added is 10g.

[0026] Preparation Example 3 The preparation method of matrix resin-3 is the same as that of preparation example 1, except that the amount of compound added in step (2) is 21g.

[0027] Preparation Example 4 The preparation method of matrix resin-4 includes the following steps: (1) Add 10g of methyl methacrylate, 5g of N-methyl-5-hexene-1-amine and 0.3g of azobisisobutyronitrile to 100ml of chloroform, react at 63℃ for 2h, and dry to obtain the polymer; (2) Under nitrogen protection, 10g of the polymer obtained in step (1) and 4g of chloromethyltrimethylsilane were added to 80ml of dichloromethane, heated to 45℃, and 0.2g of pyridine were added to react for 11-13h. The mixture was washed, distilled, and dried to obtain matrix resin-4.

[0028] Preparation Example 5 The preparation method of matrix resin-5 includes the following steps: (1) 8g of perfluorosedioic acid, 10g of pentaerythritol triacrylate, and 4ml of 85wt% sulfuric acid were added to 200ml of DMF and reacted at 75℃ for 7.5h. The mixture was then washed and dried to obtain the compound. (2) Add 17g of the compound obtained in step (1), 5g of N-methyl-5-hexene-1-amine and 0.3g of azobisisobutyronitrile to 100ml of chloroform, react at 63℃ for 2h, and dry to obtain the polymer; (3) Under nitrogen protection, 10g of the polymer obtained in step (2) and 4g of chloromethyltrimethylsilane were added to 80ml of dichloromethane, heated to 45℃, and 0.2g of pyridine were added to react for 11-13h. The mixture was washed, distilled, and dried to obtain matrix resin-5.

[0029] Preparation Example 6 The method for manufacturing an antenna radome includes the following steps: Epoxy resin E51 and curing agent T31 were mixed at a mass ratio of 100:25 and applied to the mold to a thickness of 1 mm to obtain a resin coating. Then, a 0.2 mm thick glass fiber cloth was laid on the resin coating, and the air bubbles were removed by rolling. The resin coating and glass fiber cloth laying process was repeated 3 times. The mixture was then cured at 25°C for 24 hours, followed by curing at 60°C for 4 hours. The mixture was then demolded, trimmed, and polished to a surface roughness Ra=1.5μm to obtain the antenna radome.

[0030] Preparation Example 7 The preparation method of silane coupling agent solution includes the following steps: adding 10g of γ-glycidoxypropyltrimethoxysilane to 10g of 90wt% ethanol aqueous solution and stirring for 1h to obtain silane coupling agent solution.

[0031] Example 1 A long-lifetime, superhydrophobic surface-modified radome includes an radome body and a functional coating applied to the surface of the radome. The functional coating consists of a top layer and a bottom layer directly applied to the radome body from top to bottom. The raw materials for preparing the top layer, by weight, include the following: 60 parts of matrix resin-1, 7 parts of nano titanium dioxide, 5 parts of tridecafluorooctyltriethoxysilane, 33 parts of methylphenyl silicone resin, 0.7 parts of UV-327, 0.4 parts of antioxidant 1010, and 135 parts of acetone.

[0032] The method for fabricating a long-lifetime, superhydrophobic surface-modified radome in this embodiment includes the following steps: S1. Stir matrix resin-1, nano titanium dioxide, tridecylfluorooctyltriethoxysilane, methylphenyl silicone resin, UV-327, antioxidant 1010 and acetone at 50-60℃ for 60 min to obtain the surface solution. S2. Apply the silane coupling agent solution to the radome with a coating thickness of 0.2 mm and dry it at 40-50℃ for 7 hours to obtain the bottom layer. Then apply the top layer solution to the bottom layer with a coating thickness of 0.4 mm, cure it at 50℃ for 7 hours, and finally cure it at 110℃ for 2.5 hours to obtain the surface-modified radome.

[0033] Example 2 A long-lifetime, superhydrophobic surface-modified radome includes an radome body and a functional coating applied to the surface of the radome. The functional coating consists of a top layer and a bottom layer directly applied to the radome body from top to bottom. The raw materials for preparing the top layer, by weight, include the following: 60 parts of matrix resin-1, 5 parts of nano titanium dioxide, 3 parts of tridecafluorooctyltriethoxysilane, 30 parts of methylphenyl silicone resin, 0.5 parts of UV-327, 0.3 parts of antioxidant 1010, and 120 parts of acetone.

[0034] The method for fabricating a long-lifetime, superhydrophobic surface-modified radome in this embodiment includes the following steps: S1. The matrix resin-1, nano titanium dioxide, tridecafluorooctyltriethoxysilane, methylphenyl silicone resin, UV-327, antioxidant 1010 and acetone are stirred at 50°C for 70 min to obtain the surface solution. S2. The silane coupling agent solution is coated onto the radome with a thickness of 0.1 mm and dried at 40°C for 8 hours to obtain the bottom layer. Then, the top layer solution is coated onto the bottom layer with a thickness of 0.3 mm. After curing at 40°C for 6 hours, it is finally cured at 100°C for 2 hours to obtain the surface-modified radome.

[0035] Example 3 A long-lifetime, superhydrophobic surface-modified radome includes an radome body and a functional coating applied to the surface of the radome. The functional coating consists of a top layer and a bottom layer directly applied to the radome body from top to bottom. The raw materials for preparing the top layer, by weight, include the following: 135 parts of matrix resin-1, 8 parts of nano titanium dioxide, 8 parts of tridecafluorooctyltriethoxysilane, 35 parts of methylphenyl silicone resin, 1 part of UV-327, 0.5 parts of antioxidant 1010, and 150 parts of acetone.

[0036] The method for fabricating a long-lifetime, superhydrophobic surface-modified radome in this embodiment includes the following steps: S1. The matrix resin-1, nano titanium dioxide, tridecafluorooctyltriethoxysilane, methylphenyl silicone resin, UV-327, antioxidant 1010 and acetone are stirred at 60℃ for 50 min to obtain the surface solution. S2. The silane coupling agent solution is coated onto the radome with a thickness of 0.3 mm and dried at 50°C for 6 hours to obtain the bottom layer. Then, the top layer solution is coated onto the bottom layer with a thickness of 0.5 mm. After curing at 60°C for 8 hours, it is finally cured at 120°C for 3 hours to obtain the surface-modified radome.

[0037] Example 4 A long-lifetime, superhydrophobic surface-modified radome and its preparation method are disclosed. The specific implementation method is the same as in Example 1, except that the matrix resin-1 is replaced with an equal amount of matrix resin-2.

[0038] Example 5 A long-lifetime, superhydrophobic surface-modified radome and its preparation method are disclosed. The specific implementation method is the same as in Example 1, except that the matrix resin-1 is replaced with an equal amount of matrix resin-3.

[0039] Example 6 A long-lifetime, superhydrophobic surface-modified radome and its preparation method are disclosed. The specific implementation method is the same as in Example 1, except that the matrix resin-1 is replaced with an equal amount of matrix resin-4.

[0040] Example 7 A long-lifetime, superhydrophobic surface-modified radome and its preparation method are disclosed. The specific implementation method is the same as in Example 1, except that the matrix resin-1 is replaced with an equal amount of matrix resin-5.

[0041] Performance testing (1) Damp heat aging test: The initial contact angle of the surface modified radomes obtained in each embodiment was tested. Then, the surface modified radomes were placed at 85°C and 85%RH for 170 hours and the contact angle was tested again.

[0042] (2) Sand erosion test: The contact angle of 1L of sand after erosion is tested according to the ASTM D968-15 sand drop method.

[0043] The test results are shown in Table 1.

[0044] Table 1 Comparison of experimental data from Examples 1-3 in Table 1 shows that the surface-modified radome prepared by this invention has good hydrophobicity and aging resistance, and the functional coating has good adhesion. Comparison of Example 4 with Example 1 shows that the change in the ratio of perfluorosepiacetic acid to pentaerythritol triacrylate may lead to incomplete reaction of the carboxyl groups, resulting in decreased aging resistance of the coating under humid and hot conditions. Comparison of Example 5 with Example 1 shows that the change in the ratio of methyl methacrylate to the compound, with an excessive number of fluorinated segments, may lead to over-rigidification of the coating, decreased impact resistance, and reduced adhesion. Comparison of Example 6 with Example 1 shows that the compound prepared without the addition of perfluorosepiacetic acid and pentaerythritol triacrylate has a higher surface energy and significantly reduced hydrophobicity. Comparison of Example 7 with Example 1 shows that the absence of methyl methacrylate may lead to decreased flexibility, over-rigidification of the coating, decreased impact resistance, and significantly reduced adhesion.

[0045] (3) Testing the dielectric constant of the surface-modified radomes prepared in Examples 1-3: Dielectric constant vector grid method (10 GHz), the test results are shown in Table 2: Table 2 According to the data in Table 2, the surface-modified radome prepared by the present invention has good hydrophobicity and aging resistance while maintaining electrical performance.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A long-lifetime, superhydrophobic surface-modified radome, characterized in that, The device includes an antenna radome and a functional coating applied to the surface of the radome. The functional coating consists of a top layer and a bottom layer directly applied to the antenna radome, from top to bottom. The raw materials for preparing the top layer, by weight, include the following: 60-80 parts of matrix resin, 5-8 parts of nano-reinforcing agent, 3-8 parts of crosslinking agent, 30-35 parts of silicone resin, 0.5-1 part of light stabilizer, 0.3-0.5 parts of antioxidant, and 120-150 parts of solvent.

2. The long-lifetime, superhydrophobic surface-modified radome according to claim 1, characterized in that, The method for preparing the matrix resin includes the following steps: (1) Perfluorosaturated sebacic acid, pentaerythritol triacrylate, and sulfuric acid were added to DMF and reacted at 70-80℃ for 7-8 hours. The mixture was then washed and dried to obtain the compound. (2) Methyl methacrylate, the compound obtained in step (1), N-methyl-5-hexene-1-amine and the initiator were added to chloroform and reacted at 60-65℃ for 1.5-2.5h. After drying, the polymer was obtained. (3) Under nitrogen protection, the polymer obtained in step (2) and chloromethyltrimethylsilane were added to dichloromethane, heated to 40-50℃, and pyridine was added to react for 11-13h. The mixture was then washed, distilled, and dried to obtain the matrix resin.

3. The long-lifetime, superhydrophobic surface-modified radome according to claim 2, characterized in that, The mass ratio of perfluorosedioic acid to pentaerythritol triacrylate in step (1) is (0.5-0.9):

1.

4. The long-lifetime, superhydrophobic surface-modified radome according to claim 2, characterized in that, The mass ratio of methyl methacrylate to the compound in step (2) is 1:(0.5-2).

5. The long-lifetime, superhydrophobic surface-modified radome according to claim 2, characterized in that, The mass ratio of the polymer to chloromethyltrimethylsilane in step (3) is 1:(0.2-0.6).

6. The long-lifetime, superhydrophobic surface-modified radome according to claim 1, characterized in that, The nano-reinforcing agent is nano-titanium dioxide.

7. The long-lifetime, superhydrophobic surface-modified radome according to claim 1, characterized in that, The crosslinking agent is tridecafluorooctyltriethoxysilane.

8. The long-lifetime, superhydrophobic surface-modified radome according to claim 1, characterized in that, The organosilicon resin is methylphenyl silicone resin.

9. The long-lifetime, superhydrophobic surface-modified radome according to claim 1, characterized in that, The raw material for preparing the bottom layer is a silane coupling agent solution.

10. A method for preparing a long-lifetime, superhydrophobic surface-modified radome according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Stir the matrix resin, nano-reinforcing agent, crosslinking agent, organosilicon resin, light stabilizer, antioxidant, and solvent at 50-60℃ for 50-70 minutes to obtain the surface solution. S2. The base material is coated onto the radome with a thickness of 0.1-0.3 mm and dried at 40-50℃ for 6-8 hours to obtain the base layer. Then, a surface solution is coated onto the obtained base layer with a thickness of 0.3-0.5 mm. The coating is then cured at 40-60℃ for 6-8 hours and finally cured at 100-120℃ for 2-3 hours to obtain the surface-modified radome.

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