Preparation and use method of anti-static wave-transparent coating for unmanned aerial vehicle radome

Abstract

The application discloses a preparation and use method of an anti-static wave-transparent coating for a UAV radar cover, wherein the coating is prepared from a silicon-containing polymethyl acrylate resin, a curing agent, a defoaming agent, a leveling agent, an active diluent and an anti-static agent, and comprises the following steps: (1) preparation of the anti-static wave-transparent coating; (2) application of the anti-static wave-transparent coating to the radar cover and coating construction; and (3) curing of the coating. The anti-static effect of the application is good, the attenuation of a radar signal is reduced through selection of materials and optimization of a formula, and efficient work of a radar system is ensured. Through adjustment of the type and content of conductive fillers, the coating can effectively prevent static electricity accumulation under various environmental conditions, and prevent interference of static electricity discharge on the radar system. Through addition of a weather-resistant reinforcing agent, the stability of the coating in a harsh environment such as ultraviolet light, salt fog and temperature change is improved, and the service life of the coating is prolonged.

Description

Technical Field

[0001] The present invention belongs to the technical field of antistatic coatings, and in particular relates to a preparation and use method of an antistatic wave-transparent coating for a drone radome. Background Art

[0002] Under complex weather conditions, the intense friction between the radome and the air of a high-speed drone can generate static electricity on its surface. If this static electricity isn't released promptly, it can accumulate to a certain level and cause a discharge, posing a potential threat to the radome and its internal electronic equipment, such as the antenna. Furthermore, the radome is often subjected to the impact of raindrops, hail, and other impacts. This prolonged impact can damage the radome's skin, compromising its structural safety and electrical quality. Therefore, antistatic coatings used in aircraft radomes must not only be able to conduct static electricity but also possess excellent mechanical properties. As a critical component of an aircraft, the radome's primary mission is to protect the aircraft from harsh environments while ensuring the proper propagation of electromagnetic signals. Therefore, the performance of the wave-transmitting material directly determines the radome's application range.

[0003] Antistatic coatings are functional coatings that conduct static electricity and eliminate accumulated static charges. They are primarily classified as additive and intrinsic. Currently, most widely used antistatic coatings are additive, achieving this conductivity by adding a certain amount of conductive filler to a non-conductive base resin. However, the antistatic coatings currently used in radomes often rely on conductive powders such as conductive carbon black, conductive mica, and conductive ATO to achieve their antistatic effect. The addition of these powders typically exceeds 20%, resulting in suboptimal dielectric properties in the coating, which in turn affects the wave transmission capability of the drone radome.

[0004] In summary, traditional antistatic coatings for radomes have the following problems: (1) Some traditional coatings have poor wave transmission performance in specific frequency bands, which will cause attenuation or reflection of radar signals, affecting the normal operation of the radar system. (2) Traditional antistatic coatings may not have a good antistatic effect in high humidity, low humidity or high dust environments, and are prone to static electricity accumulation. (3) The deterioration of the coating will lead to a decrease in antistatic performance or even peeling, affecting the protective function of the radome and increasing maintenance costs. Some traditional coatings have insufficient adhesion to the radome substrate and are easy to fall off. (4) Traditional coatings have a short service life and require frequent maintenance or replacement. High maintenance costs will increase the overall operating cost of the drone and reduce economic benefits. Summary of the Invention

[0005] The present invention discloses a preparation and use method of an anti-static wave-transparent coating for a UAV radar cover, with the purpose of solving the problems described in the background technology part (1) to (4).

[0006] To achieve the above purpose, the technical solution of this invention is:

[0007] A method for preparing and using an anti-static wave-transparent coating for a drone radome, wherein the coating is prepared from a silicon-containing polymethacrylate resin, a curing agent, a defoaming agent, a leveling agent, a reactive diluent, and an antistatic agent, and comprises the following steps:

[0008] (1) Preparation of antistatic wave-transmitting coating;

[0009] (2) Apply anti-static wave-transmitting coating to the radome and perform coating construction;

[0010] (3) Coating curing.

[0011] Preferably, the silicon-containing polymethacrylate resin is prepared by copolymerization of methyl methacrylate, styrene, n-butyl acrylate and acrylamide.

[0012] Preferably, the step (1) adopts a wet chemical method to synthesize the antistatic wave-transparent coating, and the specific steps are as follows: in a four-mouth reaction kettle equipped with a stirrer, a reflux condenser and a thermometer, methyl methacrylate, 2-ethylhexyl acrylate, ethyl acrylate, styrene, n-butyl acrylate and acrylamide are added in sequence according to a set mass ratio, a mixed solvent is selected, and the order of adding the materials is: first add the mixed solvent, then add each monomer in sequence, and finally add the initiator; the reaction temperature is controlled in the range of 50-84°C; after the reaction is completed, a defoaming agent, a reactive diluent and an antistatic agent are added in sequence.

[0013] Preferably, in the step (1), the mass ratio is set as follows: 35-50 parts of methyl methacrylate, 3-8 parts of 2-ethylhexyl acrylate, 14-20 parts of ethyl acrylate, 7-15 parts of styrene, 8-12 parts of n-butyl acrylate and 9-23 parts of acrylamide are added in sequence.

[0014] Preferably, in the step (1), the initiator is an oil-soluble azo compound, the defoaming agent is one or more of trioctyl phosphate, glycerol monostearate, and methyl silicone oil, the active diluent is one or more of neodecanoic acid glycidyl ester, alkylene glycidyl ether, and toluene glycidyl ether; and the antistatic agent is one or more of monoalkyl ether phosphate, lauryl amide propyl amine oxide, and dodecyl dimethyl amine oxide.

[0015] Preferably, in the step (1), the mass fraction of each monomer is controlled to be 15% to 40% of the total mass of the antistatic wave-transparent coating.

[0016] Preferably, the mixed solvent in step (1) is one or more of ethyl acetate, isopropyl alcohol (IPA) and methyl isobutyl ketone (MIBK), and the total mass thereof is between 40% and 60% of the total mass of the antistatic wave-transparent coating.

[0017] Preferably, in step (1), the mass of the defoaming agent is between 0.5% and 1.5% of the total mass of the antistatic wave-transparent coating.

[0018] Preferably, in step (1), the initiator selected from oil-soluble azo-based polymerization initiators is azobisisobutyronitrile or azobisisovaleronitrile.

[0019] Preferably, in step (1), the mass of the reactive diluent is between 2% and 4% of the total mass of the antistatic wave-transparent coating.

[0020] Preferably, in step (1), the mass of the antistatic agent is between 7.5% and 15% of the total mass of the antistatic wave-transparent coating.

[0021] Preferably, the step (2) includes the following specific steps: the surface of the radome needs to be pretreated before construction: first, the surface is cleaned with anhydrous ethanol to remove oil and impurities; then it is wiped with a lint-free cloth; then the surface is blown dry with a clean air gun; in order to improve the adhesion of the coating, the surface of the radome is lightly polished with fine sandpaper. According to actual needs, plasma treatment can be selected to activate the surface of the radome, and then the anti-static wave-transparent coating is sprayed on the surface of the radome.

[0022] Preferably, in the step (3), the sprayed coating is naturally dried at room temperature, and the drying time is controlled between 2 and 24 hours according to the thickness of the coating; or, to accelerate curing, it is heated in an oven at 60-100° C., and the curing time is 0.5-4 hours.

[0023] The beneficial effects of the preparation and use method of the anti-static wave-transparent coating for UAV radome of the present invention are:

[0024] The coating material of the present invention has a low dielectric constant and low dielectric loss, ensuring that electromagnetic waves can efficiently penetrate the coating, reducing signal attenuation and distortion, thereby maintaining the high sensitivity and accuracy of the radar system. The coating can quickly conduct away static charges, avoid potential damage to radar systems and other electronic equipment caused by electrostatic discharge, and improve the stability and reliability of the system. The coating material can resist ultraviolet radiation, salt spray corrosion, and chemical erosion, maintain long-term performance stability, and adapt to various harsh environmental conditions. The coating material usually has a low density, which helps to reduce the overall weight of the radome, which is especially important for drones that pursue high performance and long endurance. The coating has excellent adhesion to the radome substrate, and at the same time has certain wear resistance and mechanical strength, and can withstand vibration and friction during flight. By combining these advantages, the anti-static wave-transparent coating for drone radomes not only improves the performance of the radar system, but also enhances the survivability and mission execution efficiency of drones in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 , a diagram showing the electrostatic attraction ability of the anti-static wave-transparent coating provided by the present invention and various plastic surfaces (PET, PTFE, Nylon, PI) to PS microspheres after being rubbed with fingers. DETAILED DESCRIPTION

[0026] The following description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0027] The following embodiments may be understood as individually expressing a part of a local structure or method of the present invention, or may be understood as a combination of the embodiments to explain the connotation of a larger structure or method of the present invention.

[0028] Example 1

[0029] A method for preparing and using an anti-static wave-transparent coating for a drone radome, wherein the coating is prepared from a silicon-containing polymethacrylate resin, a curing agent, a defoaming agent, a leveling agent, a reactive diluent, and an antistatic agent, and comprises the following steps:

[0030] (1) Preparation of antistatic wave-transmitting coating;

[0031] (2) Apply anti-static wave-transmitting coating to the radome and perform coating construction;

[0032] (3) Coating curing.

[0033] Example 2

[0034] Based on Example 1, this example discloses that the silicon-containing polymethacrylate resin is prepared by copolymerization of methyl methacrylate, styrene, n-butyl acrylate and acrylamide.

[0035] Example 3

[0036] Based on Example 2, this embodiment discloses:

[0037] The step (1) adopts a wet chemical method to synthesize the antistatic wave-transparent coating, and the specific steps are as follows: in a four-mouth reaction kettle equipped with a stirrer, a reflux condenser and a thermometer, six monomers of methyl methacrylate, 2-ethylhexyl acrylate, ethyl acrylate, styrene, n-butyl acrylate and acrylamide are added in sequence according to a set mass ratio; in order to promote uniform dispersion of the monomers, a mixed solvent is selected, and the order of adding the materials is: first adding the mixed solvent, then adding each monomer in sequence, and finally adding the initiator; the reaction temperature is controlled in the range of 50-84°C; this temperature range matches the decomposition temperature of the initiator, which is conducive to the full progress of the polymerization reaction; after the reaction is completed, a defoaming agent, a reactive diluent and an antistatic agent are added in sequence.

[0038] Example 4

[0039] Based on Example 3, this embodiment discloses:

[0040] In the step (1), the initiator is an oil-soluble azo compound, the defoaming agent is one or more of trioctyl phosphate, glycerol monostearate, and methyl silicone oil, the active diluent is one or more of neodecanoic acid glycidyl ester, alkylene glycidyl ether, and toluene glycidyl ether; and the antistatic agent is one or more of monoalkyl ether phosphate, lauryl amide propyl amine oxide, and dodecyl dimethyl amine oxide.

[0041] Example 5

[0042] Based on Example 4, this embodiment discloses:

[0043] In the step (1), the mass fraction of each monomer is controlled to account for 15% of the total mass of the antistatic wave-transparent coating.

[0044] The mixed solvent in step (1) is one or more of ethyl acetate, isopropyl alcohol (IPA) and methyl isobutyl ketone (MIBK), and the total mass of the mixed solvent accounts for 60% of the total mass of the antistatic wave-transparent coating.

[0045] Example 6

[0046] Based on Example 4, this embodiment discloses:

[0047] In the step (1), the mass fraction of each monomer is controlled to account for 40% of the total mass of the antistatic wave-transparent coating.

[0048] The mixed solvent in step (1) is one or more of ethyl acetate, isopropyl alcohol (IPA) and methyl isobutyl ketone (MIBK), and the total mass of the mixed solvent accounts for 40% of the total mass of the antistatic wave-transmitting coating.

[0049] Example 7

[0050] Based on Example 4, this embodiment discloses:

[0051] In the step (1), the mass of the defoaming agent accounts for 0.5% of the total mass of the antistatic wave-transparent coating.

[0052] In the step (1), the initiator selected from the oil-soluble azo group to initiate the polymerization is azobisisobutyronitrile.

[0053] In the step (1), the mass of the reactive diluent accounts for 2% of the total mass of the antistatic wave-transparent coating.

[0054] In the step (1), the mass of the antistatic agent accounts for 7.5% of the total mass of the antistatic wave-transparent coating.

[0055] Example 8

[0056] Based on Example 4, this embodiment discloses:

[0057] In the step (1), the mass of the defoaming agent accounts for 1.5% of the total mass of the antistatic wave-transparent coating.

[0058] In the step (1), the initiator selected from the oil-soluble azo group to initiate the polymerization is azobisisovaleronitrile.

[0059] In the step (1), the mass of the reactive diluent accounts for 4% of the total mass of the antistatic wave-transparent coating.

[0060] In the step (1), the mass of the antistatic agent accounts for 15% of the total mass of the antistatic wave-transparent coating.

[0061] Example 9

[0062] Based on the above embodiments, this embodiment discloses: the step (2) includes the following specific steps: the surface of the radome needs to be pretreated before construction: first, use anhydrous ethanol to clean the surface to remove oil and impurities; then wipe it with a lint-free cloth; then blow dry the surface with a clean air gun; to improve the adhesion of the coating, use fine sandpaper to lightly polish the surface of the radome. According to actual needs, plasma treatment can be selected to activate the surface of the radome, and then anti-static wave-transparent coating is sprayed on the surface of the radome.

[0063] Example 10

[0064] Based on the above embodiment, this embodiment discloses that: in the step (3), the sprayed coating is naturally dried at room temperature, and the drying time is controlled between 2 and 24 hours according to the coating thickness; or, to accelerate curing, it is heated in an oven at 60-100°C for a curing time of 0.5-4 hours; the performance indicators of the cured coating are as follows: adhesion ≥ 4B level, film thickness 30-40 μm, surface resistivity 1-30 MΩ / sq (the specific value is affected by thickness and substrate), dielectric constant 1-4, loss tangent value <0.1. In the 2-40 GHz frequency band, electromagnetic wave transmittance ≥ 96%.

[0065] Example 11

[0066] In a four-mouthed reactor equipped with a stirrer, reflux condenser, and thermometer, six monomers—methyl methacrylate (40 parts), 2-ethylhexyl acrylate (3 parts), ethyl acrylate (20 parts), styrene (15 parts), n-butyl acrylate (8 parts), and acrylamide (14 parts)—were added in the order of mass (representing 30% of the total coating mass). To promote uniform dispersion of the monomers, a mixed solvent of ethyl acetate, isopropyl alcohol, and methyl isobutyl ketone (MIBK) was selected in a ratio of 3:5:2, representing 52% of the total mass. The order of addition was as follows: first add the mixed solvent, then add each monomer in sequence, and finally add the initiator, azobisisobutyronitrile. The reaction temperature was controlled within the 72°C range, which matches the initiator's decomposition temperature and facilitates the polymerization reaction. An oil-soluble azo compound was used as the initiator. After the reaction is complete, a defoamer (2 parts trioctyl phosphate, 1 part glyceryl monostearate, 2 parts methyl silicone oil, representing 1% of the total mass), a reactive diluent (1 part neodecanoic acid glycidyl ester, 3 parts alkylene glycidyl ether, 1 part toluene glycidyl ether, representing 3% of the total mass), and an antistatic agent (1 part monoalkyl ether phosphate, 1 part lauryl amide propylamine oxide, 5 parts dodecyl dimethylamine oxide, representing 14% of the total mass) are added in sequence. First, clean the surface with anhydrous ethanol to remove oil and impurities; then wipe with a lint-free cloth; and then blow dry the surface with a clean air gun. To improve coating adhesion, plasma treatment is used for surface activation for 5 minutes. Spray coating is then performed at a pressure of 7 kPa. After spraying, the surface is dried at room temperature for 6 hours.

[0067] Example 12

[0068] In a four-mouthed reactor equipped with a stirrer, reflux condenser, and thermometer, six monomers—methyl methacrylate (50 parts), 2-ethylhexyl acrylate (8 parts), ethyl acrylate (18 parts), styrene (7 parts), n-butyl acrylate (8 parts), and acrylamide (9 parts)—were added in specific proportions (representing 35% of the total weight). To promote uniform dispersion of the monomers, a mixed solvent of ethyl acetate, isopropanol, and methyl isobutyl ketone (MIBK) was selected in a ratio of 2:4:1, representing 45% of the total weight. The order of addition was as follows: first add the mixed solvent, then add each monomer in sequence, and finally add the initiator, azobisisobutyronitrile. The reaction temperature was controlled within the 65°C range, which matches the initiator's decomposition temperature and facilitates the polymerization reaction. The initiator system employed an oil-soluble azo compound. After the reaction is completed, add defoaming agent (2 parts of trioctyl phosphate, 1 part of glycerol monostearate, whose mass is 1.5% of the total mass), active diluent (1 part of neodecanoic acid glycidyl ester, 2 parts of toluene glycidyl ether, whose mass is 4% of the total mass) and antistatic agent (1 part of monoalkyl ether phosphate, 8 parts of lauramide propylamine oxide, whose mass is 14.5% of the total mass) in sequence. First, use anhydrous ethanol to clean the surface to remove oil and impurities; then wipe it with a lint-free cloth; then blow dry the surface with a clean air gun. To improve the adhesion of the coating, use 800 mesh sandpaper to lightly polish the surface. Then spray at a pressure of 7kPa and dry it at room temperature for 6 hours after spraying.

[0069] Example 13

[0070] In a four-mouthed reactor equipped with a stirrer, reflux condenser, and thermometer, six monomers—methyl methacrylate (35 parts), 2-ethylhexyl acrylate (8 parts), ethyl acrylate (14 parts), styrene (8 parts), n-butyl acrylate (12 parts), and acrylamide (23 parts)—were added in specific proportions (representing 30% of the total mass). To promote uniform dispersion of the monomers, a mixed solvent of ethyl acetate, isopropanol, and methyl isobutyl ketone (MIBK) was selected in a ratio of 1:6:3, representing 50% of the total mass. The order of addition was as follows: first add the mixed solvent, then add each monomer in sequence, and finally add the initiator, azobisisobutyronitrile. The reaction temperature was controlled within the 72°C range, which matches the initiator's decomposition temperature and facilitates the polymerization reaction. The initiator system employed an oil-soluble azo compound. After the reaction is completed, add defoaming agent (2 parts of trioctyl phosphate, the mass of which is 1.5% of the total mass), active diluent (1 part of neodecanoic acid glycidyl ester, 3 parts of alkylene glycidyl ether, 1 part of toluene glycidyl ether, the mass of which is 4% of the total mass) and antistatic agent (1 part of monoalkyl ether phosphate, 8 parts of dodecyl dimethylamine oxide, the mass of which is 14.5% of the total mass) in sequence. First, use anhydrous ethanol to clean the surface to remove oil and impurities; then wipe it with a lint-free cloth; then blow dry the surface with a clean air gun. To improve the adhesion of the coating, polish the surface with 1200 mesh sandpaper. Then spray it at a pressure of 15kPa and dry it at room temperature for 4 hours after spraying.

Claims

1. A method for preparing an anti-static wave-transparent coating for a drone radome, characterized by: The steps include: (1) Preparation of anti-static wave-transmitting coating; (2) Apply anti-static wave-transmitting coating to radome and perform coating construction; (3) Coating curing; The step (1) adopts a wet chemical method to synthesize the antistatic wave-transparent coating, and the specific steps are as follows: in a four-mouth reaction kettle equipped with a stirrer, a reflux condenser and a thermometer, methyl methacrylate, 2-ethylhexyl acrylate, ethyl acrylate, styrene, n-butyl acrylate and acrylamide are added in sequence according to a set mass ratio, a mixed solvent is selected, and the order of adding materials is: first adding the mixed solvent, then adding each monomer in sequence, and finally adding the initiator; the reaction temperature is controlled in the range of 50-84°C; after the reaction is completed, a defoaming agent, a reactive diluent and an antistatic agent are added in sequence; In the step (1), the mass ratio is set as follows: 35-50 parts of methyl methacrylate, 3-8 parts of 2-ethylhexyl acrylate, 14-20 parts of ethyl acrylate, 7-15 parts of styrene, 8-12 parts of n-butyl acrylate and 9-23 parts of acrylamide are added in sequence; In the step (1), the initiator is an oil-soluble azo compound, the defoaming agent is one or more of trioctyl phosphate, glycerol monostearate, and methyl silicone oil, the active diluent is one or more of neodecanoic acid glycidyl ester, alkylene glycidyl ether, and toluene glycidyl ether; the antistatic agent is one or more of monoalkyl ether phosphate, lauryl amide propyl amine oxide, and dodecyl dimethyl amine oxide; In the step (1), the mass fraction of the monomer is controlled to be 15% to 40% of the total mass of the antistatic wave-transmitting coating; the mixed solvent is one or more of ethyl acetate, isopropyl alcohol (IPA) and methyl isobutyl ketone (MIBK), and the total mass thereof is between 40% and 60% of the total mass of the antistatic wave-transmitting coating; the mass of the defoaming agent is between 0.5% and 1.5% of the total mass of the antistatic wave-transmitting coating; the initiator is an oil-soluble azo-type azo-type azobisisobutyronitrile or azobisisovaleronitrile; the mass of the reactive diluent is between 2% and 4% of the total mass of the antistatic wave-transmitting coating; and the mass of the antistatic agent is between 7.5% and 15% of the total mass of the antistatic wave-transmitting coating.

2. The method for preparing the antistatic wave-transparent coating for a drone radome according to claim 1, wherein: The step (2) includes the following specific steps: the surface of the radome needs to be pretreated before construction: first, the surface is cleaned with anhydrous ethanol to remove oil and impurities; then it is wiped with a lint-free cloth; then the surface is blown dry with a clean air gun; in order to improve the adhesion of the coating, the surface of the radome is lightly polished with fine sandpaper. According to actual needs, plasma treatment can be selected to activate the surface of the radome, and then the anti-static wave-transparent coating is sprayed on the surface of the radome.

3. The method for preparing an anti-static wave-transmitting coating for a drone radome according to claim 2, characterized in that: In the step (3), the sprayed coating is naturally dried at room temperature, and the drying time is controlled between 2 and 24 hours according to the thickness of the coating; or, to accelerate the curing, it is heated in an oven at 60-100°C, and the curing time is 0.5-4 hours.

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