High weather resistant coating for base station radome and preparation method thereof

Abstract

The application discloses a kind of high weather-resistant paint for base station radome and preparation method thereof, belong to coating preparation technical field.The high weather-resistant paint for base station radome is composed of the following weight parts components: 22-38 parts of fluoroethylene-vinyl ether resin, 8-16 parts of hydroxy acrylic resin, 10-18 parts of titanium white, 5-10 parts of barium sulfate, 0.5-1.5 parts of nano silicon dioxide, 0.4-1.2 parts of dispersing agent, 0.2-0.6 parts of leveling agent, 0.1-0.4 parts of defoaming agent, 1-2.7 parts of composite weather-resistant agent, 0.4-1.2 parts of composite adhesion aid and 10-22 parts of solvent.The coating prepared according to the above-mentioned substances has excellent weather resistance, salt spray resistance and adhesion.

Description

Technical Field

[0001] This invention belongs to the field of coating preparation technology, specifically relating to a high weather-resistant coating for base station antenna radomes and its preparation method. Background Technology

[0002] As a critical structural component protecting antenna systems from external environmental influences, the performance of base station radomes directly affects the stable operation and lifespan of communication equipment. With the rapid development of next-generation communication technologies such as 5G, base station radomes are exposed to complex climatic environments for extended periods, facing multiple challenges including ultraviolet radiation, acid rain erosion, drastic temperature changes, and mechanical wear. This places stringent requirements on the weather resistance of coatings. Traditional coatings, due to insufficient aging resistance, are prone to chalking, cracking, and decreased transmittance, leading to increased signal transmission loss and high maintenance costs. While existing fluorocarbon / acrylic coatings for outdoor protection possess some weather resistance, their application in base station radomes still struggles to simultaneously maintain adhesion retention and transmittance stability under long-term ultraviolet aging, humid heat, and salt spray conditions. Especially after long-term service, increased water absorption, weakened interfacial bonding, or accelerated aging and chalking can easily lead to fluctuations in dielectric parameters, further affecting the electromagnetic wave transmittance of the radome. Therefore, there is an urgent need to develop a coating system for base station radomes that combines high weather resistance, adhesion stability, and transmittance friendliness.

[0003] Patent CN121554657A discloses a high weather-resistant, atmospheric-pressure polymerizable acrylic resin and its coating preparation process. The resin is obtained by free radical polymerization of monomers comprising the following parts by weight: 30-50 parts hard monomer, 15-35 parts soft monomer, 2-8 parts functional monomer I containing active crosslinking functional groups, 5-15 parts functional monomer II containing weather-resistant structural units, and 1-5 parts unsaturated carboxylic acid monomer. The preparation method employs a stepwise dropwise addition process: first, 60-80% of the mixed monomer solution is added dropwise under reflux conditions for polymerization; then, the remaining monomer and initiator are added dropwise and the reaction is carried out at elevated temperature, all under atmospheric pressure. This invention also provides a high weather-resistant coating containing this resin. Through the synergy of a specific monomer combination and a stepwise process, this invention endows the resin with excellent intrinsic weather resistance and balanced mechanical properties under atmospheric pressure. The resulting coating exhibits significant gloss and color retention after long-term outdoor aging, making it suitable for high-end outdoor protection and decoration applications. Although the high weather-resistant coating prepared by the above method performs well in outdoor protection applications, it still has certain drawbacks when applied to base station radomes. Because base station radomes are exposed to harsh environments such as high-intensity ultraviolet radiation, extreme temperature differences, and salt spray corrosion for extended periods, the coating may still exhibit slight chalking after prolonged use, leading to a slight decrease in surface transmittance. Therefore, further optimization of the monomer ratio or introduction of novel weather-resistant additives is necessary. Summary of the Invention

[0004] The purpose of this invention is to provide a high weather-resistant coating for base station antenna radomes and its preparation method, in order to solve the technical problem of poor weather resistance and water resistance of coatings in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a high weather-resistant coating for base station antenna radomes, comprising the following components by weight: 22-38 parts fluoroethylene-vinyl vinyl ether resin, 8-16 parts hydroxyl acrylic resin, 10-18 parts titanium dioxide, 5-10 parts barium sulfate, 0.5-1.5 parts nano silica, 0.4-1.2 parts dispersant, 0.2-0.6 parts leveling agent, 0.1-0.4 parts defoamer, 1-2.7 parts composite weather-resistant agent, 0.4-1.2 parts composite adhesion aid, and 10-22 parts solvent.

[0006] Preferably, the preparation method of the composite weather-resistant agent includes the following steps: Q1: 4-acetylenetrifluorotoluene, silver carbonate and trimethylsilyl azide were added sequentially to a container containing dimethyl sulfoxide, stirred and mixed, then distilled water was added, and the reaction was heated. After the reaction was completed, the mixture was diluted, extracted, rotary evaporated and purified to obtain intermediate 1. Q2: Add intermediate 1 and triethylenediamine to a container, seal the reaction under a nitrogen atmosphere, and after the reaction is complete, purify to obtain intermediate 2; add intermediate 2 to a container containing ethyl acetate, stir to dissolve, add trifluoroacetic anhydride and triethylamine, stir to react at room temperature, dilute, extract, rotary evaporate, and purify to obtain intermediate 3. Q3: Add intermediate 3 to a container containing ethanol, stir to dissolve, add hydrazine hydrate, heat and stir to react, after the reaction is complete, extract, rotary evaporate, purify, and obtain the composite weathering agent.

[0007] In the above process, the synthesis reaction formula of the composite weather-resistant agent is as follows: The mass spectrometry analysis results of intermediate 1 were: m / z: 213.05 (100.0%), 214.05 (10.8%); the mass spectrometry analysis results of intermediate 2 were: m / z: 185.05 (100.0%), 186.05 (9.8%); the mass spectrometry analysis results of intermediate 3 were: m / z: 281.03 (100.0%), 282.03 (12.0%); and the mass spectrometry analysis results of the composite weathering agent were: m / z: 295.05 (100.0%), 296.06 (12.0%), 296.05 (1.1%).

[0008] Preferably, in Q1, the ratio of 4-acetylenetrifluorotoluene, silver carbonate, trimethylsilyl azide, dimethyl sulfoxide, and distilled water is (1.62-1.94) g : (0.251-0.295) g : (1.02-1.26) g : (8-12) mL : (0.32-0.41) mL. The mixture is heated to 80-83℃ and reacted for 1-2 h. Ethyl acetate is added for dilution, and the mixture is extracted with a mixed solution of ethyl acetate and petroleum ether in a volume ratio of 1:(2-4).

[0009] Preferably, in Q2, the ratio of intermediate 1 to triethylenediamine is (0.32-0.44) g: (0.018-0.027) g, the sealed reaction temperature is 110-120℃, and the reaction time is 1-2 h; the ratio of intermediate 2, ethyl acetate, trifluoroacetic anhydride to triethylamine is (1.36-2.11) g: (4.5-5.8) mL: (2.12-2.87) mL: (2.05-2.93) mL, the reaction is stirred at room temperature for 10-12 h, ethyl acetate is added for dilution, and extraction is performed with saturated sodium chloride aqueous solution.

[0010] Preferably, in Q3, the ratio of intermediate 3, ethanol and hydrazine hydrate is (0.266-0.304) g: (1-2) mL: (0.42-0.57) mL, the mixture is heated to 80-84℃ and stirred for 16-24 h, and then extracted with a saturated sodium chloride aqueous solution.

[0011] Preferably, the preparation method of the composite adhesion aid includes the following steps: S1: 6-fluoro-2-aminophenol, 4-nitrophthalonitrile, anhydrous potassium carbonate and N,N-dimethylformamide were added to a container, stirred and mixed, and heated under nitrogen atmosphere. After the reaction was completed, the mixture was cooled, filtered, added to an aqueous sodium hydroxide solution, washed, and dried under vacuum to obtain a solid product. S2: The solid product, 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene and 4,4-diaminodiphenyl sulfone were added to a container, heated and stirred until homogeneous, then degassed under vacuum and filtered to obtain the composite adhesion aid.

[0012] In the above process, the synthesis reaction formula of the composite adhesion aid is as follows: The mass spectrometry analysis results of the solid products were as follows: m / z: 253.07 (100.0%), 254.07 (15.3%), 255.07 (1.5%), 254.06 (1.1%).

[0013] Preferably, in S1, the ratio of 6-fluoro-2-aminophenol, 4-nitrophthalonitrile, anhydrous potassium carbonate, and N,N-dimethylformamide is (11.8-13.6) g : (33.9-35.8) g : (26.6-28.5) g : (110-130) mL. The reaction is carried out at 90-94℃ for 6-8 h, the concentration of sodium hydroxide aqueous solution is 1 mol / L, the mixture is washed with deionized water, and vacuum dried at 60-70℃ for 20-24 h.

[0014] Preferably, in step S2, the ratio of the solid product, 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene, and 4,4-diaminodiphenyl sulfone is (8.21-12.66) g : (16.56-20.53) g : (8.36-10.84) g, and the mixture is heated to 110-120°C.

[0015] Preferably, the dispersant is composed of one or more of sodium polyacrylate, sodium polynaphthalene sulfonate, sodium lignin sulfonate, and sodium methylene bisnaphthalene sulfonate; the leveling agent is composed of one or more of leveling agent CAB-381-2, leveling agent BYK-358, and leveling agent BYK-333; the defoamer is composed of one or more of isopropanol, tributyl phosphate, defoamer BYK-066N, and defoamer Foamaster MO 2190; and the solvent is composed of one or more of butyl acetate, methyl isobutyl ketone, and n-butanol.

[0016] Preferably, the method for preparing a high weather-resistant coating for a base station radome includes the following steps: Step 1: Mix the filtered fluoroethylene-vinyl vinyl ether resin and hydroxyl acrylic resin, then add 40% solvent, stir and mix, then add dispersant and defoamer, and continue stirring to obtain a mixed slurry; Step 2: Add titanium dioxide, barium sulfate and nano silica to the mixed slurry in sequence, stir at high speed, add composite weathering agent, stir evenly, add composite adhesion aid, continue stirring, add leveling agent, stir and mix, add the remaining solvent to adjust viscosity, stir, let stand, filter, and obtain high weather-resistant coating for base station antenna radome.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention applies the prepared composite weathering agent and composite adhesion aid to coatings, which can effectively improve the coating's UV aging resistance, damp heat resistance and adhesion performance.

[0018] 2. The composite weathering agent obtained in this invention, when applied to coatings, can significantly improve the coating's resistance to UV aging, gloss and color retention, resistance to damp heat, salt spray, and anti-chalking properties. Simultaneously, due to its low surface energy from its fluorinated structure, it can reduce the retention of moisture, dirt, and rainwater film on the coating surface, thus reducing dielectric loss fluctuations. The trifluoromethyl and aromatic structures in the composite weathering agent possess strong hydrophobicity and photo-oxidation stability. The nitrogen-containing heterocyclic and hydrazine-based structures can capture free radicals and peroxides generated during photo-aging, inhibiting resin chain breakage. Furthermore, the active nitrogen-containing groups can form hydrogen bonds or chemical bonds with fluorocarbon resins and hydroxyl acrylic resins, improving compatibility and cross-linking density, thereby enhancing the coating's long-term outdoor weather resistance and adhesion stability.

[0019] 3. This invention applies the prepared composite adhesion aid to coatings, which can improve the initial adhesion and adhesion retention rate after damp heat aging, reduce the risk of blistering, cracking, and peeling of the coating under rain, salt spray, thermal cycling, and ultraviolet environments, and enhance the coating's heat resistance, water resistance, and dimensional stability. The polar groups in the composite adhesion aid can form hydrogen bonds, dipole interactions, or chemical bonds with the substrate surface and titanium dioxide, barium sulfate, and nano-silica, while participating in the coating curing network to improve interfacial bonding strength and crosslinking density; the fluorinated aromatic ether structure and fluorene-based rigid framework can reduce water absorption and improve weather resistance and heat resistance stability, thereby maintaining the adhesion stability and wave transmission reliability of the radome coating during long-term service. Detailed Implementation

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1: This example discloses a method for preparing a composite weather-resistant agent, including the following steps: Q1: 1.83 g of 4-acetylenetrifluorotoluene, 0.273 g of silver carbonate and 1.14 g of trimethylsilyl azide were added sequentially to a container containing 10 mL of dimethyl sulfoxide. After stirring and mixing, 0.36 mL of distilled water was added, and the mixture was heated to 80 °C for 2 h. After the reaction was completed, ethyl acetate was added for dilution, and the mixture was extracted with a 1:3 volume ratio of ethyl acetate and petroleum ether mixture. The mixture was then purified by rotary evaporation to obtain intermediate 1. Q2: Add 0.38g of intermediate 1 and 0.022g of triethylenediamine to a container, and react under a nitrogen atmosphere at 110℃ for 2 hours. After the reaction is complete, purify to obtain intermediate 2. Add 1.73g of intermediate 2 to a container containing 5.2mL of ethyl acetate, stir to dissolve, add 2.44mL of trifluoroacetic anhydride and 2.48mL of triethylamine, stir to react at room temperature for 12 hours, dilute with ethyl acetate, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain intermediate 3. Q3: Add 0.285g of intermediate 3 to a container containing 1.5mL of ethanol, stir to dissolve, add 0.48mL of hydrazine hydrate, heat to 80℃ and stir to react for 24h. After the reaction is completed, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain composite weathering agent.

[0022] This embodiment discloses a method for preparing a composite adhesion promoter, including the following steps: S1: 12.7g of 6-fluoro-2-aminophenol, 34.8g of 4-nitrophthalonitrile, 27.5g of anhydrous potassium carbonate and 120mL of N,N-dimethylformamide were added to a container, stirred and mixed, and heated to 90℃ for 8h under nitrogen atmosphere. After the reaction was completed, the mixture was cooled, filtered, added to a 1mol / L sodium hydroxide aqueous solution, washed with deionized water, and dried under vacuum at 60℃ for 24h to obtain a solid product. S2: Add 10.43g of solid product, 18.54g of 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene and 9.53g of 4,4-diaminodiphenyl sulfone to a container, heat to 110℃ and stir evenly, then degas under vacuum and filter to obtain the composite adhesion aid.

[0023] This embodiment discloses a high weather-resistant coating for base station antenna radomes, which is composed of the following components by weight: 30 parts fluoroethylene-vinyl vinyl ether resin, 12 parts hydroxyl acrylic resin, 14 parts titanium dioxide, 7.5 parts barium sulfate, 1 part nano silica, 0.8 parts sodium polyacrylate, 0.4 parts leveling agent CAB-381-2, 0.25 parts defoamer BYK-066N, 1.8 parts composite weather-resistant agent, 0.8 parts composite adhesion aid, and 16 parts butyl acetate.

[0024] This embodiment discloses a method for preparing a high weather-resistant coating for base station radomes, including the following steps: Step 1: Mix the filtered fluoroethylene-vinyl vinyl ether resin and hydroxyl acrylic resin, then add 40% butyl acetate, stir at 600 rpm for 15 minutes, then add sodium polyacrylate and defoamer BYK-066N, and continue stirring to obtain the mixed slurry. Step 2: Add titanium dioxide, barium sulfate, and nano-silica to the mixed slurry in sequence. Stir at 2000 rpm for 20 minutes, then add the composite weather-resistant agent and stir evenly. Add the composite adhesion promoter and continue stirring at 600 rpm for 25 minutes. Add the leveling agent CAB-381-2 and stir to mix. Add the remaining butyl acetate to adjust the viscosity, stir, let stand, and filter with a 200-mesh filter to obtain a high weather-resistant coating for base station antenna radomes.

[0025] Example 2: This example discloses a method for preparing a composite weather-resistant agent, including the following steps: Q1: 1.94 g of 4-acetylenetrifluorotoluene, 0.251 g of silver carbonate and 1.26 g of trimethylsilyl azide were added sequentially to a container containing 12 mL of dimethyl sulfoxide. After stirring and mixing, 0.32 mL of distilled water was added, and the mixture was heated to 80 °C for 2 h. After the reaction was completed, ethyl acetate was added for dilution, and the mixture was extracted with a 1:2 volume ratio of ethyl acetate and petroleum ether mixture. The mixture was then purified by rotary evaporation to obtain intermediate 1. Q2: Add 0.32g of intermediate 1 and 0.018g of triethylenediamine to a container, and react under a nitrogen atmosphere at 110℃ for 2h. After the reaction is complete, purify to obtain intermediate 2. Add 1.36g of intermediate 2 to a container containing 5.8mL of ethyl acetate, stir to dissolve, add 2.12mL of trifluoroacetic anhydride and 2.05mL of triethylamine, stir to react at room temperature for 12h, dilute with ethyl acetate, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain intermediate 3. Q3: Add 0.266g of intermediate 3 to a container containing 2mL of ethanol, stir to dissolve, add 0.57mL of hydrazine hydrate, heat to 80℃ and stir to react for 24h. After the reaction is completed, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain the composite weathering agent.

[0026] This embodiment discloses a method for preparing a composite adhesion promoter, including the following steps: S1: 11.8 g of 6-fluoro-2-aminophenol, 33.9 g of 4-nitrophthalonitrile, 26.6 g of anhydrous potassium carbonate and 110 mL of N,N-dimethylformamide were added to a container, stirred and mixed, and heated to 90 °C for 8 h under nitrogen atmosphere. After the reaction was completed, the mixture was cooled, filtered, added to a 1 mol / L sodium hydroxide aqueous solution, washed with deionized water, and dried under vacuum at 60 °C for 24 h to obtain a solid product. S2: Add 8.21g of solid product, 16.56g of 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene and 10.84g of 4,4-diaminodiphenyl sulfone to a container, heat to 110℃ and stir evenly, then degas under vacuum and filter to obtain the composite adhesion aid.

[0027] This embodiment discloses a high weather-resistant coating for base station antenna radomes, which is composed of the following components by weight: 22 parts fluoroethylene-vinyl vinyl ether resin, 8 parts hydroxyl acrylic resin, 18 parts titanium dioxide, 10 parts barium sulfate, 1.5 parts nano silica, 1.2 parts sodium methylene bis(naphthalene) sulfonate, 0.6 parts leveling agent BYK-333, 0.1 parts defoamer Foamaster MO 2190, 2.7 parts composite weather-resistant agent, 0.4 parts composite adhesion aid, and 22 parts methyl isobutyl ketone.

[0028] This embodiment discloses a method for preparing a high weather-resistant coating for base station radomes, including the following steps: Step 1: Mix the filtered fluoroethylene-vinyl vinyl ether resin and hydroxyl acrylic resin, then add 40% methyl isobutyl ketone, stir at 600 rpm for 15 min, then add sodium methylene bisnaphthalene sulfonate and defoamer Foamaster MO 2190, and continue stirring to obtain the mixed slurry. Step 2: Add titanium dioxide, barium sulfate, and nano-silica to the mixed slurry in sequence. Stir at 2000 rpm for 20 minutes, then add the composite weather-resistant agent and stir evenly. Add the composite adhesion aid and continue stirring at 600 rpm for 25 minutes. Add the leveling agent BYK-333 and stir to mix. Add the remaining methyl isobutyl ketone to adjust the viscosity, stir, let stand, and filter with a 200-mesh filter to obtain a high weather-resistant coating for base station antenna radomes.

[0029] Example 3: This example discloses a method for preparing a composite weather-resistant agent, including the following steps: Q1: 1.62 g of 4-acetylenetrifluorotoluene, 0.295 g of silver carbonate and 1.02 g of trimethylsilyl azide were added sequentially to a container containing 8 mL of dimethyl sulfoxide. After stirring and mixing, 0.41 mL of distilled water was added, and the mixture was heated to 80 °C for 2 h. After the reaction was completed, ethyl acetate was added for dilution, and the mixture was extracted with a 1:4 volume ratio of ethyl acetate and petroleum ether mixture. The mixture was then purified by rotary evaporation to obtain intermediate 1. Q2: Add 0.44g of intermediate 1 and 0.027g of triethylenediamine to a container, and react under a nitrogen atmosphere at 110℃ for 2h. After the reaction is complete, purify to obtain intermediate 2. Add 2.11g of intermediate 2 to a container containing 4.5mL of ethyl acetate, stir to dissolve, add 2.87mL of trifluoroacetic anhydride and 2.93mL of triethylamine, stir to react at room temperature for 12h, dilute with ethyl acetate, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain intermediate 3. Q3: Add 0.304g of intermediate 3 to a container containing 1mL of ethanol, stir to dissolve, add 0.42mL of hydrazine hydrate, heat to 80℃ and stir to react for 24h. After the reaction is completed, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain the composite weathering agent.

[0030] This embodiment discloses a method for preparing a composite adhesion promoter, including the following steps: S1: 13.6 g of 6-fluoro-2-aminophenol, 35.8 g of 4-nitrophthalonitrile, 28.5 g of anhydrous potassium carbonate and 130 mL of N,N-dimethylformamide were added to a container, stirred and mixed, and heated to 90 °C for 8 h under nitrogen atmosphere. After the reaction was completed, the mixture was cooled, filtered, added to a 1 mol / L sodium hydroxide aqueous solution, washed with deionized water, and dried under vacuum at 60 °C for 24 h to obtain a solid product. S2: 12.66g of solid product, 20.53g of 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene and 8.36g of 4,4-diaminodiphenyl sulfone were added to a container, heated to 110℃ and stirred until homogeneous. After vacuum degassing, the mixture was filtered to obtain the composite adhesion aid.

[0031] This embodiment discloses a high weather-resistant coating for base station antenna radomes, which is composed of the following components by weight: 38 parts fluoroethylene-vinyl vinyl ether resin, 16 parts hydroxyl acrylic resin, 10 parts titanium dioxide, 5 parts barium sulfate, 0.5 parts nano silica, 0.4 parts sodium methylene bisnaphthalene sulfonate, 0.2 parts leveling agent CAB-381-2, 0.4 parts tributyl phosphate, 1 part composite weather-resistant agent, 1.2 parts composite adhesion aid, and 10 parts butyl acetate.

[0032] This embodiment discloses a method for preparing a high weather-resistant coating for base station radomes, including the following steps: Step 1: Mix the filtered vinyl fluoride-vinyl vinyl ether resin and hydroxyl acrylic resin, then add 40% butyl acetate, stir at 600 rpm for 15 min, then add sodium methylene bisnaphthalene sulfonate and tributyl phosphate, and continue stirring to obtain a mixed slurry; Step 2: Add titanium dioxide, barium sulfate, and nano-silica to the mixed slurry in sequence. Stir at 2000 rpm for 20 minutes, then add the composite weather-resistant agent and stir evenly. Add the composite adhesion promoter and continue stirring at 600 rpm for 25 minutes. Add the leveling agent CAB-381-2 and stir to mix. Add the remaining butyl acetate to adjust the viscosity, stir, let stand, and filter with a 200-mesh filter to obtain a high weather-resistant coating for base station antenna radomes.

[0033] Example 4: This example discloses a method for preparing a composite weather-resistant agent, including the following steps: Q1: 1.76 g of 4-acetylenetrifluorotoluene, 0.262 g of silver carbonate and 1.08 g of trimethylsilyl azide were added sequentially to a container containing 9 mL of dimethyl sulfoxide. After stirring and mixing, 0.38 mL of distilled water was added, and the mixture was heated to 80 °C for 2 h. After the reaction was completed, ethyl acetate was added for dilution, and the mixture was extracted with a 1:3 volume ratio of ethyl acetate and petroleum ether mixture. The mixture was then purified by rotary evaporation to obtain intermediate 1. Q2: Add 0.35g of intermediate 1 and 0.019g of triethylenediamine to a container, and react under a nitrogen atmosphere at 110℃ for 2h. After the reaction is complete, purify to obtain intermediate 2. Add 1.55g of intermediate 2 to a container containing 4.7mL of ethyl acetate, stir to dissolve, add 2.36mL of trifluoroacetic anhydride and 2.26mL of triethylamine, stir to react at room temperature for 12h, dilute with ethyl acetate, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain intermediate 3. Q3: Add 0.275g of intermediate 3 to a container containing 1.2mL of ethanol, stir to dissolve, add 0.46mL of hydrazine hydrate, heat to 80℃ and stir to react for 24h. After the reaction is completed, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain composite weathering agent.

[0034] This embodiment discloses a method for preparing a composite adhesion promoter, including the following steps: S1: 11.9 g of 6-fluoro-2-aminophenol, 34.2 g of 4-nitrophthalonitrile, 27.2 g of anhydrous potassium carbonate and 115 mL of N,N-dimethylformamide were added to a container, stirred and mixed, and heated to 90 °C for 8 h under nitrogen atmosphere. After the reaction was completed, the mixture was cooled, filtered, added to a 1 mol / L sodium hydroxide aqueous solution, washed with deionized water, and dried under vacuum at 60 °C for 24 h to obtain a solid product. S2: Add 9.68g of solid product, 19.97g of 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene and 8.97g of 4,4-diaminodiphenyl sulfone to a container, heat to 110℃ and stir evenly, then degas under vacuum and filter to obtain the composite adhesion aid.

[0035] This embodiment discloses a high weather-resistant coating for base station antenna radomes, which is composed of the following components by weight: 26 parts fluoroethylene-vinyl vinyl ether resin, 10 parts hydroxyl acrylic resin, 12 parts titanium dioxide, 6 parts barium sulfate, 0.8 parts nano silica, 0.6 parts sodium lignosulfonate, 0.3 parts leveling agent BYK-333, 0.3 parts defoamer Foamaster MO 2190, 1.4 parts composite weather-resistant agent, 0.6 parts composite adhesion aid, and 15 parts n-butanol.

[0036] This embodiment discloses a method for preparing a high weather-resistant coating for base station radomes, including the following steps: Step 1: Mix the filtered vinyl fluoride-vinyl vinyl ether resin and hydroxyl acrylic resin, then add 40% n-butanol, stir at 600 rpm for 15 min, then add sodium lignosulfonate and defoamer Foamaster MO2190, and continue stirring to obtain the mixed slurry. Step 2: Add titanium dioxide, barium sulfate, and nano-silica to the mixed slurry in sequence. Stir at 2000 rpm for 20 minutes, then add the composite weather-resistant agent and stir evenly. Add the composite adhesion aid and continue stirring at 600 rpm for 25 minutes. Add the leveling agent BYK-333 and stir to mix. Add the remaining n-butanol to adjust the viscosity, stir, let stand, and filter with a 200-mesh filter to obtain a high weather-resistant coating for base station antenna radomes.

[0037] Example 5: This example discloses a method for preparing a composite weather-resistant agent, including the following steps: Q1: 1.88 g of 4-acetylenetrifluorotoluene, 0.287 g of silver carbonate and 1.22 g of trimethylsilyl azide were added sequentially to a container containing 11 mL of dimethyl sulfoxide. After stirring and mixing, 0.34 mL of distilled water was added, and the mixture was heated to 80 °C for 2 h. After the reaction was completed, ethyl acetate was added for dilution, and the mixture was extracted with a 1:2 volume ratio of ethyl acetate and petroleum ether mixture. The mixture was then purified by rotary evaporation to obtain intermediate 1. Q2: 0.41g of intermediate 1 and 0.025g of triethylenediamine were added to a container and reacted at 110℃ under a nitrogen atmosphere for 2 hours. After the reaction was completed, the mixture was purified to obtain intermediate 2. 1.92g of intermediate 2 was added to a container containing 5.6mL of ethyl acetate and stirred to dissolve. Then, 2.57mL of trifluoroacetic anhydride and 2.68mL of triethylamine were added and the mixture was stirred at room temperature for 12 hours. After dilution with ethyl acetate, the mixture was extracted with saturated sodium chloride aqueous solution, rotary evaporated, and purified to obtain intermediate 3. Q3: Add 0.296g of intermediate 3 to a container containing 1.8mL of ethanol, stir to dissolve, add 0.55mL of hydrazine hydrate, heat to 80℃ and stir to react for 24h. After the reaction is completed, extract with saturated sodium chloride aqueous solution, rotary evaporate, and purify to obtain composite weathering agent.

[0038] This embodiment discloses a method for preparing a composite adhesion promoter, including the following steps: S1: 13.2 g of 6-fluoro-2-aminophenol, 35.4 g of 4-nitrophthalonitrile, 28.3 g of anhydrous potassium carbonate and 125 mL of N,N-dimethylformamide were added to a container, stirred and mixed, and heated to 90 °C for 8 h under nitrogen atmosphere. After the reaction was completed, the mixture was cooled, filtered, added to a 1 mol / L sodium hydroxide aqueous solution, washed with deionized water, and dried under vacuum at 60 °C for 24 h to obtain a solid product. S2: 11.97g of solid product, 17.62g of 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene and 9.96g of 4,4-diaminodiphenyl sulfone were added to a container, heated to 110℃ and stirred until homogeneous. After vacuum degassing, the mixture was filtered to obtain the composite adhesion aid.

[0039] This embodiment discloses a high weather-resistant coating for base station antenna radomes, which is composed of the following components by weight: 34 parts fluoroethylene-vinyl vinyl ether resin, 14 parts hydroxyl acrylic resin, 16 parts titanium dioxide, 8 parts barium sulfate, 1.2 parts nano silica, 1 part sodium polynaphthalene sulfonate, 0.5 parts leveling agent BYK-358, 0.2 parts isopropanol, 2.2 parts composite weather-resistant agent, 1 part composite adhesion aid, and 18 parts methyl isobutyl ketone.

[0040] This embodiment discloses a method for preparing a high weather-resistant coating for base station radomes, including the following steps: Step 1: Mix the filtered fluoroethylene-vinyl vinyl ether resin and hydroxyl acrylic resin, then add 40% methyl isobutyl ketone, stir at 600 rpm for 15 min, then add sodium polynaphthalene sulfonate and isopropanol, and continue stirring to obtain a mixed slurry. Step 2: Add titanium dioxide, barium sulfate, and nano-silica to the mixed slurry in sequence. Stir at 2000 rpm for 20 minutes, then add the composite weather-resistant agent and stir evenly. Add the composite adhesion aid and continue stirring at 600 rpm for 25 minutes. Add the leveling agent BYK-358 and stir to mix. Add the remaining methyl isobutyl ketone to adjust the viscosity, stir, let stand, and filter with a 200-mesh filter to obtain a high weather-resistant coating for base station antenna radomes.

[0041] Comparative Example 1: Compared with Example 1, Comparative Example 1 did not add composite weathering agent in the process of preparing high weather-resistant coating for base station antenna radomes, and all other conditions remained unchanged.

[0042] Comparative Example 2: Compared with Example 1, Comparative Example 2 did not add composite adhesion aids in the process of preparing the high weather-resistant coating for base station antenna radomes, and all other conditions remained unchanged.

[0043] Performance testing: The high weather-resistant coatings prepared in Examples 1-5 and Comparative Examples 1-2 were subjected to performance tests. The high weather-resistant coatings were mixed with hexamethylene diisocyanate trimer at a mass ratio of 100:10. After mixing and stirring for 5 minutes, the mixture was allowed to mature for 10 minutes. The radome surface was then degreased, dust-removed, and polished. The matured coating was then sprayed with a thickness of 20 μm. The coating performance was then tested. Adhesion was tested according to GB / T 9286-2021; liquid resistance was tested according to GB / T 9274-1988; damp heat resistance was tested according to GB / T 1740-2007; aging resistance was tested according to GB / T 1865-2009 and GB / T 23987.3-2025; and aging was rated according to GB / T 1766-2008. The test results are shown in Table 1. Table 1 Adhesion rating was evaluated according to GB / T 9286-2021, with 0 being the best and 5 the worst. Liquid resistance, salt water resistance, appearance after damp heat, and chalking rating could be rated according to GB / T 1766-2008, with 0 indicating no obvious abnormalities and higher ratings indicating more severe blistering, peeling, chalking, or loss of gloss. A higher gloss retention value indicates better gloss retention after aging. Examples 1-5, due to the simultaneous addition of composite weathering agent and composite adhesion aid, exhibited excellent overall adhesion, liquid resistance, damp heat resistance, and aging resistance. Comparative Example 1, without the addition of composite weathering agent, mainly showed a decrease in gloss retention and increased chalking. Comparative Example 2, without the addition of composite adhesion aid, mainly showed a decrease in initial adhesion and adhesion after damp heat, indicating that the two types of aids significantly contribute to weather resistance stability and interfacial bonding stability, respectively.

[0044] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0045] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A high weather-resistant coating for base station antenna radomes, characterized in that, It is composed of the following components by weight: 22-38 parts fluoroethylene-vinyl vinyl ether resin, 8-16 parts hydroxyl acrylic resin, 10-18 parts titanium dioxide, 5-10 parts barium sulfate, 0.5-1.5 parts nano silica, 0.4-1.2 parts dispersant, 0.2-0.6 parts leveling agent, 0.1-0.4 parts defoamer, 1-2.7 parts composite weathering agent, 0.4-1.2 parts composite adhesion aid, and 10-22 parts solvent.

2. The high weather-resistant coating for base station antenna radomes according to claim 1, characterized in that, The preparation method of the composite weather-resistant agent includes the following steps: Q1: 4-acetylenetrifluorotoluene, silver carbonate and trimethylsilyl azide were added sequentially to a container containing dimethyl sulfoxide, stirred and mixed, then distilled water was added, and the reaction was heated. After the reaction was completed, the mixture was diluted, extracted, rotary evaporated and purified to obtain intermediate 1. Q2: Add intermediate 1 and triethylenediamine to a container, seal the reaction under a nitrogen atmosphere, and after the reaction is complete, purify to obtain intermediate 2; add intermediate 2 to a container containing ethyl acetate, stir to dissolve, add trifluoroacetic anhydride and triethylamine, stir to react at room temperature, dilute, extract, rotary evaporate, and purify to obtain intermediate 3. Q3: Add intermediate 3 to a container containing ethanol, stir to dissolve, add hydrazine hydrate, heat and stir to react, after the reaction is complete, extract, rotary evaporate, purify, and obtain the composite weathering agent.

3. The high weather-resistant coating for base station radomes according to claim 2, characterized in that, In Q1, the ratio of 4-acetylenetrifluorotoluene, silver carbonate, trimethylsilyl azide, dimethyl sulfoxide and distilled water is (1.62-1.94) g : (0.251-0.295) g : (1.02-1.26) g : (8-12) mL : (0.32-0.41) mL.

4. The high weather-resistant coating for base station antenna radomes according to claim 2, characterized in that, In Q2, the ratio of intermediate 1 to triethylenediamine is (0.32-0.44) g: (0.018-0.027) g; the ratio of intermediate 2, ethyl acetate, trifluoroacetic anhydride to triethylamine is (1.36-2.11) g: (4.5-5.8) mL: (2.12-2.87) mL: (2.05-2.93) mL.

5. A high weather-resistant coating for a base station antenna radome according to claim 2, characterized in that, In Q3, the ratio of intermediate 3, ethanol and hydrazine hydrate is (0.266-0.304) g : (1-2) mL : (0.42-0.57) mL.

6. The high weather-resistant coating for base station antenna radomes according to claim 1, characterized in that, The preparation method of the composite adhesion aid includes the following steps: S1: 6-fluoro-2-aminophenol, 4-nitrophthalonitrile, anhydrous potassium carbonate and N,N-dimethylformamide were added to a container, stirred and mixed, and heated under nitrogen atmosphere. After the reaction was completed, the mixture was cooled, filtered, added to an aqueous sodium hydroxide solution, washed, and dried under vacuum to obtain a solid product. S2: The solid product, 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene and 4,4-diaminodiphenyl sulfone were added to a container, heated and stirred until homogeneous, then degassed under vacuum and filtered to obtain the composite adhesion aid.

7. A high weather-resistant coating for a base station antenna radome according to claim 6, characterized in that, In S1, the ratio of 6-fluoro-2-aminophenol, 4-nitrophthalonitrile, anhydrous potassium carbonate, and N,N-dimethylformamide is (11.8-13.6) g : (33.9-35.8) g : (26.6-28.5) g : (110-130) mL.

8. A high weather-resistant coating for a base station antenna radome according to claim 6, characterized in that, In S2, the ratio of the solid product, 9,9-bis[(2,3-epoxypropoxy)phenyl]fluorene, and 4,4-diaminodiphenyl sulfone is (8.21-12.66) g : (16.56-20.53) g : (8.36-10.84) g.

9. A high weather-resistant coating for a base station antenna radome according to claim 1, characterized in that, The dispersant is composed of one or more of sodium polyacrylate, sodium polynaphthalene sulfonate, sodium lignin sulfonate, and sodium methylene bisnaphthalene sulfonate; the leveling agent is composed of one or more of leveling agent CAB-381-2, leveling agent BYK-358, and leveling agent BYK-333; the defoamer is composed of one or more of isopropanol, tributyl phosphate, defoamer BYK-066N, and defoamer Foamaster MO 2190; and the solvent is composed of one or more of butyl acetate, methyl isobutyl ketone, and n-butanol.

10. A method for preparing a high weather-resistant coating for a base station radome as described in any one of claims 1-9, characterized in that, Includes the following steps: Step 1: Mix the filtered fluoroethylene-vinyl vinyl ether resin and hydroxyl acrylic resin, then add 40% solvent, stir and mix, then add dispersant and defoamer, and continue stirring to obtain a mixed slurry; Step 2: Add titanium dioxide, barium sulfate and nano silica to the mixed slurry in sequence, stir at high speed, add composite weathering agent, stir evenly, add composite adhesion aid, continue stirring, add leveling agent, stir and mix, add the remaining solvent to adjust viscosity, stir, let stand, filter, and obtain high weather-resistant coating for base station antenna radome.

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