A UV coating and its preparation method

Abstract

This application relates to the field of UV coating technology, and mainly to a UV coating and its preparation method. A UV coating, by weight, comprises the following raw materials: polyurethane acrylate oligomer: 55-60 parts by weight; reactive diluent: 25-35 parts by weight; photoinitiator: 1-5 parts by weight; silver nanowire dispersion: 3-8 parts by weight; modified carbon nanotube dispersion: 0.5-3 parts by weight; composite dispersant: 1-3 parts by weight; leveling agent: 0.1-1 parts by weight; adhesion promoter: 0.1-1 parts by weight. The UV coating provided by this application exhibits excellent uniform dispersion, and the resulting coating possesses good mechanical properties and excellent electrical conductivity.

Description

Technical Field

[0001] This application relates to the field of UV coating technology, and mainly to a UV coating and its preparation method. Background Technology

[0002] UV vacuum electroplating coatings, as an advanced surface treatment technology, have been widely used in the automotive, electronics, home appliance, and cosmetic packaging industries due to their advantages such as environmental friendliness, high efficiency, and strong decorative properties. The basic principle is to use ultraviolet light to initiate the rapid polymerization and curing of monomers and oligomers, forming a dense, hard coating with good adhesion. Subsequently, a metal thin film is deposited or sputtered onto this coating to achieve a metallic appearance. However, traditional UV vacuum electroplating coatings mainly focus on providing excellent decorative effects (such as high gloss and mirror finish) and basic protective functions (such as wear resistance, scratch resistance, and chemical resistance).

[0003] With advancements in technology and increasingly diverse consumer demands, the market is placing higher requirements on product functionality. In many applications, coatings that merely offer decorative and basic protective functions are no longer sufficient. For example, in the electronics industry, casing coatings may need to be conductive to achieve electromagnetic shielding (EMI) or electrostatic dissipation (ESD), thereby protecting internal precision circuits from electromagnetic interference and preventing damage to users and equipment caused by static electricity buildup.

[0004] However, the introduction of functional materials (such as conductive fillers) may affect the original mechanical properties (such as hardness and flexibility) and curing behavior of UV coatings. Moreover, the compatibility of functional materials with the UV-curable resin system is a critical issue. If the materials are not dispersed evenly, not only will the functionality not be effectively realized, but defects in the coating may also occur, such as agglomeration and delamination, thereby affecting basic properties such as adhesion and abrasion resistance.

[0005] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this application is to provide a UV coating and a method for preparing the same.

[0007] The technical solution of this application is as follows: A UV coating, by weight, comprises the following raw materials: Polyurethane acrylate oligomer: 55-60 parts by weight; Reactive diluent: 25-35 parts by weight; Photoinitiator: 1-5 parts by weight; Silver nanowire dispersion: 3-8 parts by weight; Modified carbon nanotube dispersion: 0.5-3 parts by weight; Composite dispersant: 1-3 parts by weight; Leveling agent: 0.1-1 parts by weight; Adhesion promoter: 0.1-1 parts by weight.

[0008] Furthermore, the preparation of the modified carbon nanotube dispersion includes the following steps: Modified polyethyleneimine was obtained by modifying polyethyleneimine with ethyl isocyanate acrylate. Multi-walled carbon nanotubes, modified polyethyleneimine, and solvent are mixed and stirred, then filtered and evaporated to obtain a modified carbon nanotube dispersion with a solid content of 3-8%.

[0009] Furthermore, after mixing multi-walled carbon nanotubes, modified polyethyleneimine, and solvent, the mixture is stirred at 350-450 rpm for 20-45 minutes to obtain the first mixture. The first mixture is ultrasonically treated for 20-45 minutes at a power of 450-550W and a frequency of 18-22kHz; then sheared and dispersed at a speed of 9500-11000rpm for 0.5-2 hours to obtain the second mixture. The second mixture is filtered and evaporated to obtain a modified carbon nanotube dispersion with a solid content of 3-8%.

[0010] The ultrasonic cavitation effect generates microjets that impact carbon nanotube aggregates, exposing more surface active sites; high-speed shearing, on the other hand, mechanically shears the aggregates. The two work together to form a gradient energy field in time (ultrasonic 20-45 minutes + shearing 0.5-2 hours) and space (ultrasonic frequency 18-22kHz + shearing speed 9500-11000rpm), achieving a continuous process from deagglomeration to stable dispersion.

[0011] Furthermore, the preparation of modified polyethyleneimine includes the following steps: dissolving polyethyleneimine in anhydrous toluene, adding ethyl isocyanate acrylate, reacting at 75-85℃ for 3-5 hours under inert gas protection, evaporating to remove anhydrous toluene, and obtaining modified polyethyleneimine.

[0012] Furthermore, the weight ratio of polyethyleneimine to ethyl isocyanate acrylate is 1:(0.05-0.15).

[0013] Furthermore, the weight ratio of multi-walled carbon nanotubes to modified polyethyleneimine is 1:(0.05-0.15).

[0014] Furthermore, the ratio of polyethyleneimine to anhydrous toluene is 1 g : (4-6) mL; The ratio of multi-walled carbon nanotubes to solvent is 1g: (8-12)mL.

[0015] The amino groups on the PEI molecular chain undergo nucleophilic addition reactions with isocyanate groups, introducing acrylate double bonds into the PEI chain and forming a "comb-like" structure. This structure retains the polymer chain entanglement characteristics of PEI (enhancing adsorption on the carbon nanotube surface) while also hindering carbon nanotube aggregation through the stereorepulsion effect of the double bonds.

[0016] Furthermore, the composite dispersant includes one or a mixture of two of Disperbyk-180 and BYK-346.

[0017] Furthermore, the composite dispersant is a mixture of Disperbyk-180 and BYK-346 in a weight ratio of (1-3):1.

[0018] The acrylate double bonds of modified polyethyleneimine and composite dispersants (such as the polyester chain of Disperbyk-180 and the siloxane chain of BYK-346) form a bilayer adsorption structure through hydrogen bonding / π-π interaction. The inner layer is a strong chemical adsorption of modified polyethyleneimine and multi-walled carbon nanotubes, and the outer layer is a compatibility adsorption of dispersant and matrix resin, forming a three-dimensional barrier to prevent secondary aggregation.

[0019] Modified carbon nanotubes act as bridges connecting silver nanowires, forming a three-dimensional conductive network during the UV coating curing process. The nanoscale size of the carbon nanotubes fills the gaps between the silver nanowires, reducing network resistance; simultaneously, the polar groups of modified polyethyleneimine readily generate electrostatic repulsion with ions on the surface of the silver nanowires, preventing excessive aggregation of the silver nanowires.

[0020] The acrylate double bonds on modified polyethyleneimine can undergo free radical copolymerization with the double bonds of polyurethane acrylate oligomers to form a chemically bonded interface layer, which enhances the interfacial bonding force between modified carbon nanotubes and the matrix and avoids conductivity attenuation caused by carbon nanotube migration during the curing process.

[0021] During UV curing, the free radicals generated by the photoinitiator preferentially attack the acrylate double bonds on the modified polyethyleneimine, initiating the polymerization of grafted chains on the carbon nanotube surface and forming anchoring points. Simultaneously, the synergistic effect of the composite dispersant keeps the carbon nanotubes dispersed in the early stages of curing, preventing the breakage of the conductive network due to volume shrinkage. In the final coating, the modified carbon nanotubes and silver nanowires form a point-to-line composite conductive structure, ensuring high conductivity while simultaneously enhancing the coating's hardness and wear resistance through the reinforcing effect of the modified carbon nanotubes, achieving a balance between functionality and durability.

[0022] In summary, modified carbon nanotubes and silver nanowires construct a highly efficient three-dimensional conductive network within the coating. The long and rigid silver nanowires form the main conductive framework. The small and flexible modified carbon nanotubes act as bridges between the silver nanowires. This overlapping mechanism effectively fills the conductive dead zones between the silver nanowires. It significantly reduces the contact resistance between nodes, allowing for smoother electron transport. A very small amount of carbon nanotubes can multiply the conductivity while not blocking light, ensuring the coating's high transparency.

[0023] During the micro-dispersion process, the modified polyethyleneimine on the surface of the modified carbon nanotubes plays a crucial role. Its polar amino groups strongly adsorb and coordinate with the surface of the silver nanowires. This allows the two to intertwine and co-disperse uniformly within the resin, effectively preventing secondary agglomeration of the nanomaterials. This composite network also exhibits excellent toughness when the coating is bent under stress. During the UV curing stage, the acrylic double bonds on the surface of the modified carbon nanotubes copolymerize with the resin matrix. This firmly locks the entire composite conductive network of carbon nanotubes and silver wires within the cross-linked coating. The dense cross-linked network also effectively blocks oxygen and moisture, significantly improving the antioxidant lifespan of the silver nanowires.

[0024] This application also provides a method for preparing a UV coating, comprising the following steps: The polyurethane acrylate oligomer, reactive diluent, and adhesion promoter are stirred and mixed to obtain the first mixture; Add silver nanowire dispersion, modified carbon nanotube dispersion, and composite dispersant to the first mixture, stir and mix to obtain the second mixture; The second mixture is stirred and mixed with the photoinitiator and leveling agent to obtain the third mixture; The third mixture is filtered and degassed to obtain a UV coating.

[0025] Compared with the prior art, this application has the following beneficial effects: 1. A three-dimensional conductive network constructed from modified carbon nanotubes and silver nanowires achieves efficient electron transport through point-line synergy. Silver nanowires serve as a rigid framework, while nanoscale carbon nanotubes, with their flexibility, interweave within them, precisely filling the gaps between the silver nanowires and significantly reducing node contact resistance. The polar amino groups of modified polyethyleneimine electrostatically repel the ions on the surface of the silver nanowires, preventing excessive aggregation; its acrylate double bonds copolymerize with the matrix during UV curing, forming a chemically bonded interface layer that locks the carbon nanotubes in place, preventing conductivity attenuation due to migration. This overlapping mechanism allows for a significant increase in conductivity with a very small amount of carbon nanotubes, achieving a breakthrough in high conductivity with low dosage.

[0026] 2. Modified carbon nanotubes constitute only 0.5-3 parts by weight in the system, far less than the 3-8 parts by weight of silver nanowires, and their nanoscale size complements that of silver nanowires. The small and flexible nature of carbon nanotubes allows them to be uniformly dispersed in the coating without forming light scattering centers. Silver nanowires serve as the main framework for conductivity, while carbon nanotubes act only as bridges connecting the gaps. The conductive network constructed by both ensures high conductivity while, due to their extremely low dosage and uniform dispersion, ensuring high transmittance of visible light in the coating, thus achieving the dual requirements of transparency and conductivity.

[0027] 3. The flexible properties of modified carbon nanotubes endow the coating with excellent bending resistance. The acrylate double bonds of modified polyethyleneimine undergo a copolymerization reaction with the polyurethane acrylate matrix to form a dense cross-linked network, firmly locking the carbon nanotube and silver nanowire composite structure within the coating. This chemical bonding not only enhances interfacial adhesion and improves the coating's hardness and wear resistance, but also effectively blocks oxygen and moisture, extending the antioxidant lifespan of the silver nanowires and achieving a balance between conductivity, flexibility, and durability. Detailed Implementation

[0028] To facilitate understanding of this application, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of this application.

[0029] This application provides a UV coating, comprising the following raw materials by weight: Polyurethane acrylate oligomer: 55-60 parts by weight; Reactive diluent: 25-35 parts by weight; Photoinitiator: 1-5 parts by weight; Silver nanowire dispersion: 3-8 parts by weight (active ingredient content 1-10%); Modified carbon nanotube dispersion: 0.5-3 parts by weight; Composite dispersant: 1-3 parts by weight; Leveling agent: 0.1-1 parts by weight; Adhesion promoter: 0.1-1 parts by weight.

[0030] The reactive diluent includes one or a mixture of two of trimethylolpropane triacrylate and isobornyl acrylate.

[0031] The composite dispersant includes one or a mixture of two of Disperbyk-180 and BYK-346.

[0032] Preferably, the composite dispersant is a mixture of Disperbyk-180 and BYK-346 in a weight ratio of (1-3):1.

[0033] The preparation of modified carbon nanotube dispersions includes the following steps: Step a: Preparation of modified polyethyleneimine, including the following steps: Polyethyleneimine (PEI, preferably molecular weight 9500-11000) was dissolved in anhydrous toluene, and then slowly added dropwise to ethyl isocyanate acrylate. The reaction was carried out at 75-85°C for 3-5 hours under an inert gas (nitrogen) protection. The isocyanate groups were monitored by infrared spectroscopy at 1700-1750 cm⁻¹. -1 The disappearance of the characteristic absorption peak at the point indicated the completion of the reaction. Toluene was removed by rotary evaporation to obtain modified polyethyleneimine.

[0034] The ratio of polyethyleneimine to anhydrous toluene is 1 g : (4-6) mL.

[0035] The weight ratio of polyethyleneimine to ethyl isocyanate acrylate is 1:(0.05-0.15).

[0036] Step b: Mix multi-walled carbon nanotubes with modified polyethyleneimine, and add isopropanol as a solvent. In a container equipped with a stirrer, stir at 350-450 rpm for 20-45 minutes to ensure initial homogeneity and obtain the first mixture.

[0037] The weight ratio of multi-walled carbon nanotubes to modified polyethyleneimine is 1:(0.05-0.15).

[0038] The ratio of multi-walled carbon nanotubes to isopropanol is 1g: (8-12)mL.

[0039] Step c: Transfer the first mixture to an ultrasonic disperser and sonicate it for 20-45 minutes at a power of 450-550W and a frequency of 18-22kHz. Then, transfer it to a high-speed shear disperser and shear disperse it at a speed of 9500-11000rpm for 0.5-2 hours to obtain the second mixture.

[0040] Step d: The second mixture is filtered and then rotary evaporated in a rotary evaporator at 55-65℃ and a vacuum of -0.09MPa±0.005 to obtain a modified carbon nanotube dispersion with a solid content of 3-8%.

[0041] This application also provides a method for preparing a UV coating, comprising the following steps: Step 1: Add the polyurethane acrylate oligomer, reactive diluent, and adhesion promoter to a glass reactor equipped with a high-speed stirrer. Stir at 350-450 rpm for 20-45 minutes at room temperature (25℃±3) to ensure thorough mixing. This yields the first mixture.

[0042] Step 2: Slowly add silver nanowire dispersion and modified carbon nanotube dispersion to the first mixture. Then add the composite dispersant. Increase the stirring speed to 1500-2000 rpm and continue stirring for 2-4 hours. Subsequently, use a horizontal sand mill with 0.3-0.5 mm zirconia beads as the grinding media at a speed of 2500-3000 rpm, and circulate the mill three times until the dispersion fineness reaches 1-5 micrometers. This yields the second mixture.

[0043] Step 3: Reduce the stirring speed to 300-400 rpm, add the photoinitiator and leveling agent, and stir for 20-45 minutes. This will yield the third mixture.

[0044] Step 4: The third mixture is filtered through a precision filter and then degassed under a vacuum of -0.088MPa±0.008 for 15-20 minutes until no obvious bubbles are visible, thus obtaining the UV coating.

[0045] The present application will be further described below through specific embodiments.

[0046] Example 1 This embodiment discloses a UV coating, comprising the following raw materials: Polyurethane acrylate oligomer: 58 kg (purchased from Guangzhou Bahe New Material Technology Co., Ltd., BW8298 in this example); Reactive diluent: 30 kg (specifically isobornyl acrylate); Photoinitiator: 3 kg (specifically Irgacure 184); Silver nanowire dispersion: 5 kg (purchased from Beijing Zhongke Keyou Technology Co., Ltd. in this example, with an effective ingredient content of 5%); Modified carbon nanotube dispersion: 1 kg; Composite dispersant: 1.8 kg (specifically, Disperbyk-180 and BYK-346 are compounded in a weight ratio of 2:1); Leveling agent: 0.2 kg (specifically BYK-333); Adhesion promoter: 0.8 kg (specifically KH-570).

[0047] The preparation of modified carbon nanotube dispersions includes the following steps: Step a: Preparation of modified polyethyleneimine, including the following steps: 1000g of polyethyleneimine (molecular weight 10000, purchased from Wuhan Huaxiang Kejie Biotechnology Co., Ltd. in this example) was dissolved in 5000mL of anhydrous toluene, and then 100g of ethyl isocyanate acrylate was slowly added dropwise. The reaction was carried out at 80°C for 4 hours under nitrogen protection. The isocyanate groups were monitored by infrared spectroscopy at 1700-1750cm⁻¹. -1The disappearance of the characteristic absorption peak at the point indicated the completion of the reaction. Toluene was removed by rotary evaporation to obtain modified polyethyleneimine.

[0048] Step b: Mix 1000g of multi-walled carbon nanotubes (NC7000, Nanocyl in this example) with 100g of modified polyethyleneimine, and add 10000mL of isopropanol as a solvent. In a container equipped with a stirrer, stir at 400rpm for 30 minutes to ensure initial homogeneity and obtain the first mixture.

[0049] Step c: Transfer the first mixture to an ultrasonic disperser and sonicate it for 30 minutes at a power of 500W and a frequency of 20kHz. Then, transfer it to a high-speed shear disperser and shear disperse it at a speed of 10,000rpm for 1 hour to obtain the second mixture.

[0050] Step d: The second mixture was filtered and then rotary evaporated in a rotary evaporator at 60°C and a vacuum of -0.09 MPa to obtain a modified carbon nanotube dispersion with a solid content of 5%.

[0051] This embodiment also provides a method for preparing a UV coating, including the following steps: Step 1: Add the polyurethane acrylate oligomer, reactive diluent, and adhesion promoter to a glass reactor equipped with a high-speed stirrer. Stir at 400 rpm for 30 minutes at room temperature (25°C) until fully mixed. This yields the first mixture.

[0052] Step 2: Slowly add silver nanowire dispersion and modified carbon nanotube dispersion to the first mixture. Then add the composite dispersant. Increase the stirring speed to 1800 rpm and continue stirring for 2.5 hours. Subsequently, use a horizontal sand mill with 0.4 mm zirconia beads as the grinding media at 2800 rpm for three cycles of grinding to achieve a dispersion fineness of 2 micrometers. The second mixture is then obtained.

[0053] Step 3: Reduce the stirring speed to 350 rpm, add the photoinitiator and leveling agent, and stir for 30 minutes. This will yield the third mixture.

[0054] Step 4: The third mixture is filtered through a 5-micron precision filter and then degassed under a vacuum of -0.088 MPa for 18 minutes until no obvious bubbles are visible, thus obtaining the UV coating.

[0055] Performance testing: 1. Surface resistivity: The four-probe method (Keithley 2400 source meter) was used to test the resistivity of solid insulating materials according to GB / T 1410-2006 "Test methods for volume resistivity and surface resistivity of solid insulating materials".

[0056] The coating thickness obtained by UV coating is controlled at 12 micrometers.

[0057] 2. Adhesion: The cross-cut test was conducted according to GB / T 9286-1998 "Cross-cut test for paint and varnish films". The coating was applied to a PC substrate and then cured.

[0058] 3. Pencil hardness: Tested according to GB / T 6739-2006 "Determination of paint film hardness by pencil method for paints and varnishes".

[0059] 4. Color difference (ΔE): Randomly select one point on the UV coating surface as the baseline point; then randomly select five points on the UV coating surface as test points and measure them using a colorimeter. If the color difference between all five test points and the baseline point is less than 2, it is considered qualified; otherwise, it is unqualified.

[0060] Test results: 1. Surface resistivity: 2×10 4 Ω / sq.

[0061] 2. Adhesion: Grade 0.

[0062] 3. Pencil hardness: 2H.

[0063] 4. Color difference: Pass.

[0064] Example 2 The difference from Example 1 is that the composite dispersant is Disperbyk-180.

[0065] Test results: 1. Surface resistivity: 2.2 × 10⁻⁶ 4 Ω / sq.

[0066] 2. Adhesion: Grade 0.

[0067] 3. Pencil hardness: 2H.

[0068] 4. Color difference: Pass.

[0069] Comparative Example 1 The difference from Example 1 is that polyethyleneimine is used instead of modified polyethyleneimine.

[0070] Test results: 1. Surface resistivity: 3.8 × 10⁻⁶ 4 Ω / sq.

[0071] 2. Adhesion: Level 1.

[0072] 3. Pencil hardness: H.

[0073] 4. Color difference: Not up to standard.

[0074] Comparative Example 1 used polyethyleneimine instead of modified polyethyleneimine, resulting in the loss of acrylate double bonds, preventing the formation of a chemically bonded interface layer with the matrix resin. This led to easy migration of carbon nanotubes, causing breakage of the conductive network. Simultaneously, electrostatic repulsion was weakened, silver nanowires easily aggregated, and contact resistance increased. Polyethyleneimine exhibited poor compatibility with the matrix resin, resulting in weak interfacial adhesion. Aggregation of silver nanowires caused stress concentration within the coating, easily leading to coating peeling during cross-cut adhesion testing. Weak interfacial adhesion reduced the coating's scratch resistance. Unmodified polyethyleneimine lacked sufficient flexibility, failing to effectively transfer stress and reducing hardness. Aggregation of silver nanowires formed localized "hot spots," enhancing light scattering. Uneven dispersion of unmodified polyethyleneimine resulted in differences in coating transmittance and localized color deepening.

[0075] Comparative Example 2 The difference from Example 1 is that a carbon nanotube dispersion is used instead of a modified carbon nanotube dispersion.

[0076] The preparation of carbon nanotube dispersions includes the following steps: Step a: Add 1000g of multi-walled carbon nanotubes (NC7000, Nanocyl in this example) to 10000mL of isopropanol. In a container equipped with a stirrer, stir at 400rpm for 30 minutes to ensure initial homogeneity and obtain the first mixture.

[0077] Step b: Transfer the first mixture to an ultrasonic disperser and sonicate it for 30 minutes at a power of 500W and a frequency of 20kHz. Then, transfer it to a high-speed shear disperser and shear disperse it at a speed of 10,000 rpm for 1 hour to obtain the second mixture.

[0078] Step c: The second mixture is filtered and then evaporated in a rotary evaporator at 60°C and a vacuum of -0.09 MPa to obtain a carbon nanotube dispersion with a solid content of 5%.

[0079] Test results: 1. Surface resistivity: 4.8 × 10⁻⁶ 4 Ω / sq.

[0080] 2. Adhesion: Level 1.

[0081] 3. Pencil hardness: H.

[0082] 4. Color difference: Not up to standard.

[0083] Comparative Example 2 used a carbon nanotube dispersion instead of a modified carbon nanotube dispersion. Ordinary carbon nanotubes lack the chemical adsorption properties of modified polyethyleneimine, easily agglomerating to form conductive dead zones. The increased dispersion fineness prevents effective overlap of silver nanowires, leading to increased network resistance. Furthermore, the lack of a chemically bonded interface layer weakens the adhesion between the carbon nanotubes and the matrix resin; agglomerates cause internal defects in the coating, easily resulting in coating detachment during cross-cut adhesion testing. Agglomeration of carbon nanotubes causes strong light scattering, forming dark spots; simultaneously, uneven dispersion leads to differences in coating transmittance, significantly increasing color variation.

[0084] Comparative Example 3 The difference from Example 1 is that the modified carbon nanotube dispersion is omitted.

[0085] Test results: 1. Surface resistivity: 1.5 × 10⁻⁶ 5 Ω / sq.

[0086] 2. Adhesion: Grade 0.

[0087] 3. Pencil hardness: H.

[0088] 4. Color difference: Pass.

[0089] In Comparative Example 3, the lack of bridging effect of modified carbon nanotubes resulted in high contact resistance of silver nanowires; relying solely on silver nanowires for conductivity resulted in insufficient network density and a significant increase in resistance.

[0090] Regarding the phenomenon that adhesion and color difference performance are not significantly affected, the inventor speculates: Adhesion: Without the influence of carbon nanotubes, the synergistic effect of silver nanowires and dispersants can still provide basic adhesion, therefore, the adhesion still shows a grade of 0.

[0091] Color difference: Without the influence of carbon nanotubes on blackness, the coating relies solely on the plasma resonance effect of silver nanowires, resulting in an overall transparent or pale yellow tone. Color uniformity is easier to control, thus demonstrating acceptable color difference.

[0092] Based on the above test data, it can be seen that the UV coating provided in this application has good uniformity and dispersion, and the resulting coating has good mechanical properties and excellent conductivity.

[0093] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of this application.

Claims

1. A UV coating, characterized in that, The following raw materials are included in the preparation according to parts by weight: Polyurethane acrylate oligomer: 55-60 parts by weight; Reactive diluent: 25-35 parts by weight; Photoinitiator: 1-5 parts by weight; Silver nanowire dispersion: 3-8 parts by weight; Modified carbon nanotube dispersion: 0.5-3 parts by weight; Composite dispersant: 1-3 parts by weight; Leveling agent: 0.1-1 parts by weight; Adhesion promoter: 0.1-1 parts by weight.

2. The UV coating according to claim 1, characterized in that, The preparation of modified carbon nanotube dispersions includes the following steps: Modified polyethyleneimine was obtained by modifying polyethyleneimine with ethyl isocyanate acrylate. Multi-walled carbon nanotubes, modified polyethyleneimine, and solvent are mixed and stirred, then filtered and evaporated to obtain a modified carbon nanotube dispersion with a solid content of 3-8%.

3. The UV coating according to claim 2, characterized in that, Multi-walled carbon nanotubes, modified polyethyleneimine, and solvent are mixed and stirred at 350-450 rpm for 20-45 minutes to obtain the first mixture. The first mixture is ultrasonically treated for 20-45 minutes at a power of 450-550W and a frequency of 18-22kHz; then sheared and dispersed at a speed of 9500-11000rpm for 0.5-2 hours to obtain the second mixture. The second mixture is filtered and evaporated to obtain a modified carbon nanotube dispersion with a solid content of 3-8%.

4. The UV coating according to claim 2, characterized in that, The preparation of modified polyethyleneimine includes the following steps: polyethyleneimine is dissolved in anhydrous toluene, ethyl isocyanate acrylate is added, and the mixture is reacted at 75-85℃ for 3-5 hours under inert gas protection. The anhydrous toluene is then evaporated to remove the modified polyethyleneimine.

5. The UV coating according to claim 4, characterized in that, The weight ratio of polyethyleneimine to ethyl isocyanate acrylate is 1:(0.05-0.15).

6. The UV coating according to claim 4, characterized in that, The weight ratio of multi-walled carbon nanotubes to modified polyethyleneimine is 1:(0.05-0.15).

7. The UV coating according to claim 4, characterized in that, The ratio of polyethyleneimine to anhydrous toluene is 1 g : (4-6) mL; The ratio of multi-walled carbon nanotubes to solvent is 1g:(8-12)mL.

8. The UV coating according to claim 1, characterized in that, The composite dispersant includes one or a mixture of two of Disperbyk-180 and BYK-346.

9. The method for preparing the UV coating according to claim 8, characterized in that, The composite dispersant is a mixture of Disperbyk-180 and BYK-346 in a weight ratio of (1-3):

1.

10. A method for preparing a UV coating based on any one of claims 1-9, characterized in that, Includes the following steps: The polyurethane acrylate oligomer, reactive diluent, and adhesion promoter are stirred and mixed to obtain the first mixture; Add silver nanowire dispersion, modified carbon nanotube dispersion, and composite dispersant to the first mixture, stir and mix to obtain the second mixture; The second mixture is stirred and mixed with the photoinitiator and leveling agent to obtain the third mixture; The third mixture is filtered and degassed to obtain a UV coating.