A toughened UV and moisture dual-curing three-proof paint and its preparation method

Abstract

The present invention belongs to the technical field of paint coatings and specifically relates to a toughened UV moisture dual-curing conformal coating and a preparation method thereof. The conformal coating comprises the following raw material components in weight percentage: 39-84 wt% of tricyclodecane dimethanol diacrylate, 13-45 wt% of a bifunctional polyurethane acrylate resin containing acryloyl and isocyanate groups, 2-10 wt% of a toughening modifier, and 1-6 wt% of a photoinitiator, based on the total raw material amount. The toughening modifier is selected from at least one of bisacryloyloxy-modified polyisobutylene, diene-containing EPDM rubber, carboxyl-terminated liquid nitrile rubber, and vinyl-terminated nitrile rubber. The conformal coating of the present invention is resistant to cracking when subjected to external forces and has excellent adhesion, significantly reducing problems such as wrinkling, cracking, and insufficient adhesion caused by system shrinkage. It also has high tensile strength and low water vapor transmission.

Description

Technical Field

[0001] The invention belongs to the technical field of paint coatings, and particularly relates to a toughened UV moisture dual-curing conformal coating and a preparation method thereof. Background Art

[0002] With the acceleration of global industrialization and urbanization, the demand for efficient, environmentally friendly, and energy-saving surface treatment technologies continues to increase. UV curing technology is favored for its fast curing and environmentally friendly characteristics. UV conformal coatings, as UV conformal materials, are widely used in electronics, automobiles, construction, and other fields.

[0003] Currently, most traditional UV conformal coatings use IBOA (isobornyl acrylate) as a monomer. Studies have shown that IBOA itself carries a considerable risk of allergic reactions. To prevent skin sensitization caused by contact with IBOA and to meet diverse market demands, it is necessary to develop a sustainable, biofriendly, IBOA-free UV conformal coating system.

[0004] Currently available is a UV conformal coating containing tricyclodecane dimethanol diacrylate (DCPDA) that offers dual UV and moisture curing properties. It cures rapidly under UV radiation and, in areas shielded from direct sunlight, can also cure under moisture. This dual curing mechanism ensures uniformity and durability of the coating. The formulation is free of allergenic ingredients, ensuring users do not have to worry about allergic reactions when using or handling electronic devices coated with this conformal coating.

[0005] However, in UV conformal coatings with dual UV and moisture curing properties, compared to other monomers (such as IBOA, which has a rigid bicyclic isoborneol group and a flexible acrylate backbone, with one acrylate double bond per molecule, forming a linear polymer chain with better toughness when polymerized), DCPDA, as a photocurable monomer, contains a larger tricyclic structure with two acrylate groups on each ring. This means that DCPDA has a large structural steric hindrance and greater rigidity, resulting in poorer toughness. The product formed after curing often has higher hardness and brittleness. This brittleness makes the material prone to breakage when subjected to external forces.

[0006] It should be noted that this part of the present invention only provides background technology related to the present invention and does not necessarily constitute prior art or public known technology. Summary of the Invention

[0007] The present invention aims to overcome the drawback of prior art UV conformal coatings containing tricyclodecane dimethanol diacrylate that are prone to cracking due to UV and moisture dual-curing properties. The present invention provides a toughened UV moisture dual-curing conformal coating and a preparation method thereof. The coating is less prone to cracking when subjected to external forces and has excellent adhesion, significantly reducing problems such as wrinkling, cracking, and insufficient adhesion caused by system shrinkage. Furthermore, the coating has high tensile strength and low water vapor transmission rate.

[0008] To achieve the above objectives, in a first aspect, the present invention provides a toughened UV moisture dual-curing conformal coating, comprising the following raw material components in weight percentage: based on the total amount of raw materials, 39-84 wt% of tricyclodecane dimethanol diacrylate, 13-45 wt% of a bifunctional polyurethane acrylate resin containing acryloyl and isocyanate groups, 2-10 wt% of a toughening modifier, and 1-6 wt% of a photoinitiator; the weight ratio of tricyclodecane dimethanol diacrylate to toughening modifier is 100:2.38-25.60; wherein the toughening modifier is selected from at least one of bisacryloyloxy-modified polyisobutylene, diene-containing EPDM rubber, carboxyl-terminated liquid nitrile rubber, and vinyl-terminated nitrile rubber.

[0009] In the present invention, the toughening modifier preferably has a long carbon chain and the main chain carbon number of the carbon chain is 5-20.

[0010] In some preferred embodiments of the present invention, the bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group has a long carbon chain, and the main chain of the carbon chain has 4-17 carbon atoms.

[0011] In some preferred embodiments of the present invention, the raw material components of the toughened UV moisture dual-curing conformal coating further include at least one auxiliary agent selected from the group consisting of a catalytic moisture curing agent, a free radical inhibitor, a fluorescent brightener, and an adhesion promoter.

[0012] In some more preferred embodiments of the present invention, the raw material components of the toughened UV moisture dual-curing conformal coating include: based on the total amount of raw materials, 0-0.4 wt% catalytic moisture curing agent, preferably 0.2-0.4 wt% catalytic moisture curing agent, 0.03-0.07 wt% free radical inhibitor, 0.01-0.03 wt% fluorescent brightener, 0-1.5 wt% adhesion promoter, preferably 0.5-1.5 wt% adhesion promoter.

[0013] In some preferred embodiments of the present invention, the catalytic moisture curing agent is selected from 、 、C 12 H 24 At least one of N2O2; and / or,

[0014] The free radical inhibitor is selected from 、 、 、 、 、 , at least one of 2,6-di-tert-butyl-p-cresol; wherein, R and R1 are each independently selected from an alkyl group having 4 to 8 carbon atoms.

[0015] In the present invention, preferably, the fluorescent whitening agent is selected from C 26 H 26 N2O2S、C 24 H 14 O2N2、C 28 H 18 N2O2、C 30 H 26 O2 at least one; and / or, the adhesion promoter is selected from alkyl acrylate phosphate and / or methacryloxy silane.

[0016] In a second aspect, the present invention provides a method for preparing a toughened UV moisture dual curing conformal coating, which is used to prepare the toughened UV moisture dual curing conformal coating described in the first aspect, and the preparation method comprises the following steps:

[0017] S1, first mixing required amounts of tricyclodecane dimethanol diacrylate, a toughening regulator, and a bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group to obtain a first mixed solution;

[0018] S2, introducing a photoinitiator into the first mixed solution for a second mixing to obtain a second mixed solution;

[0019] S3. Then degassing is performed under vacuum conditions.

[0020] In some preferred embodiments of the present invention, the preparation method further includes: introducing a free radical inhibitor and a fluorescent whitening agent into the second mixture in S2, and then introducing a catalytic moisture curing agent and / or an adhesion promoter into the obtained second mixed liquid for a third mixing to obtain a third mixed liquid, and then degassing the third mixed liquid in S3.

[0021] In some preferred embodiments of the present invention, the conditions for the first mixing include: a stirring speed of 1500-2300 rpm, and a stirring time of 100-150 s.

[0022] In some preferred embodiments of the present invention, the second mixing conditions include: a stirring speed of 2100-2500 rpm, and a stirring time of 150-200 s.

[0023] In some preferred embodiments of the present invention, the conditions for the third mixing include: a stirring speed of 1500-2000 rpm, and a stirring time of 50-100 s.

[0024] In some preferred embodiments of the present invention, the degassing time is 1-3 minutes.

[0025] Beneficial effects:

[0026] The present invention, through the above-mentioned technical solution, adds a toughening modifier to the formulation of tricyclodecane dimethanol diacrylate, a bifunctional polyurethane acrylate resin, and a photoinitiator. Tricyclodecane dimethanol diacrylate and the bifunctional polyurethane acrylate resin, as monomers, generate free radicals under the action of the photoinitiator, which then undergo polymerization with the double bonds in the toughening modifier molecules, thereby improving the toughness of the conformal coating. Furthermore, the weight ratio of tricyclodecane dimethanol diacrylate to the toughening modifier is controlled within an appropriate range. With an appropriate weight ratio, a suitable viscosity for uniform reaction is ensured, which is conducive to use. This allows for dual curing methods, including free radical curing and moisture curing, while also modulating the brittleness of the material, making it less susceptible to breakage when subjected to external forces. Furthermore, the material exhibits excellent adhesion, can bond tightly to the substrate, significantly reduces wrinkling, cracking, and insufficient adhesion caused by system shrinkage, and exhibits high tensile strength and low water vapor transmission. Furthermore, the toughening modifier is controlled to have a long carbon chain with a main chain carbon number of 5-20, which facilitates post-processing.

[0027] In a preferred embodiment of the present invention, the toughening modifier includes bisacryloyloxy-modified polyisobutylene. The bisacryloyloxy-modified polyisobutylene can participate in a free radical polymerization reaction with tricyclodecane dimethanol diacrylate and a difunctional polyurethane acrylate resin as monomers under the action of a photoinitiator. The bisacryloyloxy groups contained in the bisacryloyloxy group serve as crosslinking points. The three components are crosslinked to form a three-dimensional crosslinked network, making the interior of the material more compact, reducing pores, and hindering the penetration of water molecules, thereby being more conducive to reducing water vapor permeation while also improving toughness. The combined effect of toughening and reducing water vapor permeation in this preferred embodiment is relatively better than the effect when the toughening modifier uses diene-containing EPDM rubber, carboxyl-terminated liquid nitrile rubber, or vinyl-terminated nitrile rubber. Furthermore, in this preferred embodiment, if the weight ratio of tricyclodecane dimethanol diacrylate to the toughening modifier is consistent with the present invention, the combined effect of reducing water vapor permeability while simultaneously improving toughness is more pronounced. If the weight ratio is not consistent with the present invention, the cross-linked material may either be insufficiently tight, resulting in a high water vapor permeability, or, if the toughening modifier is excessive, excessive cross-linking may make the material brittle, generate microcracks, and increase permeability.

[0028] When the toughening regulator uses diene-containing EPDM rubber, carboxyl-terminated liquid nitrile rubber, and vinyl-terminated nitrile rubber, it is beneficial to the partial toughening effect and the water vapor permeability is also reduced to a certain extent. One possible speculation is that EPDM rubber reduces the water vapor permeability through its material properties. The main chain of EPDM rubber is composed of chemically stable saturated hydrocarbons and only contains unsaturated double bonds in the side chains. This material itself is impermeable and can effectively prevent water penetration. The cyano group in nitrile rubber enhances the interaction between molecules, makes the molecular chains more tightly arranged, reduces the free volume inside the material, and the dense molecular structure significantly extends the diffusion path of water molecules in the material, thereby reducing the overall permeation rate. The DCPDA and the polyurethane acrylate resin are combined with tricyclodecane dimethanol diacrylate and a bifunctional polyurethane acrylate resin as monomers under the action of a photoinitiator. The photoinitiator absorbs photons to generate active free radicals, which trigger a free radical polymerization reaction between the DCPDA and the polyurethane acrylate resin, forming a cross-linked structure. The rubber is embedded in this structure as a dispersed phase, acting as a reinforcing phase to further densify the material structure and reduce the water vapor transmission rate of the material. Furthermore, the overall solution of the present invention using diene-containing EPDM rubber achieves the combined effect of reducing water vapor transmission while also improving toughness, which is relatively superior to solutions using carboxyl-terminated liquid nitrile rubber or vinyl-terminated nitrile rubber.

[0029] The preparation method of the present invention is simple and convenient to operate and has strong practicality. The obtained three-proof paint has no risk of human sensitization and has good moisture-proof, salt spray-proof and mildew-proof effects. DETAILED DESCRIPTION

[0030] In the present invention, unless otherwise stated, directional words such as "up, down, left, right" are generally understood in conjunction with the directions shown in actual applications.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0032] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0033] The endpoints of the ranges and any values disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values can be combined to form one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed herein. The terms "optional" and "optional" both mean that a range may or may not be included (or may or may not be present).

[0034] In a first aspect, the present invention provides a toughened UV moisture dual-curing conformal coating, comprising the following raw material components in weight percentage: based on the total raw material amount, 39-84 wt% of tricyclodecane dimethanol diacrylate, 13-45 wt% of a bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group, 2-10 wt% of a toughening modifier, and 1-6 wt% of a photoinitiator; and the weight ratio of tricyclodecane dimethanol diacrylate to toughening modifier is 100:2.38-25.60, preferably 100:11.00-25.60.

[0035] The toughening regulator is selected from at least one of bisacryloyloxy-modified polyisobutylene, diene-containing EPDM rubber, carboxyl-terminated liquid nitrile rubber, and vinyl-terminated nitrile rubber.

[0036] Preferably, the toughening modifier has a long carbon chain and the main chain carbon number of the carbon chain is 5-20.

[0037] The present invention uses the above-mentioned specific double-bond-containing rubber, which can be uniformly dispersed in the resin and form a cross-linked network with the matrix through chemical reaction or physical action, or the rubber has active groups and has the ability to react again and extend the chain, thereby improving material properties (such as toughness, aging resistance, and heat resistance) and increasing the material recycling rate.

[0038] In the present invention, the rubber containing double bonds can be purchased commercially or prepared by a method in the prior art.

[0039] In some preferred embodiments of the present invention, the raw material components of the toughened UV moisture dual-curing conformal coating further include at least one auxiliary agent selected from the group consisting of a catalytic moisture curing agent, a free radical inhibitor, a fluorescent brightener, and an adhesion promoter.

[0040] In some more preferred embodiments of the present invention, the toughened UV moisture dual-curing conformal coating comprises, based on the total raw materials, 0-0.4 wt% of a catalytic moisture curing agent, preferably 0.2-0.4 wt% of a catalytic moisture curing agent, 0.03-0.07 wt% of a free radical inhibitor, 0.01-0.03 wt% of a fluorescent brightener, and 0-1.5 wt% of an adhesion promoter, preferably 0.5-1.5 wt% of an adhesion promoter. Using this appropriate ratio of catalytic moisture curing agent, free radical inhibitor, fluorescent brightener, and adhesion promoter further reduces production costs and improves the quality of the conformal coating.

[0041] In some preferred embodiments of the present invention, the catalytic moisture curing agent is selected from (i.e. dimorpholinyl diethyl ether), (i.e. N,N-dimethyl-p-toluidine), C 12 H 24 At least one of N2O2.

[0042] In some preferred embodiments of the present invention, the free radical inhibitor is selected from (i.e. 2,6-di-tert-butyl-4-methylphenol), (3,5-di-tert-butyl-4-hydroxyphenylpropionic acid C7-C9 mixed ester, where i represents isomerization), (Octamine (CAS: 37338-62-8)), 、 (i.e. 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl free radical), (i.e., 4,4-di(phenylisopropyl)diphenylamine); wherein R and R1 are each independently selected from an alkyl group having 4 to 8 carbon atoms. For example, the alkyl group can be selected from C4H9, C8H 17 or other alkyl chains.

[0043] In some preferred embodiments of the present invention, the fluorescent whitening agent is selected from C 26 H 26 N2O2S (i.e. 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene), C 24 H 14 O2N2 (i.e. 1,4-2 (benzoxazolyl-2-yl) naphthalene), C 28 H 18 N2O2 (i.e. 4,4-bis(2-benzoxazolyl)stilbene), C30 H 26 O2 (i.e., 4,4-bis(2-dimethoxyphenyl)biphenyl).

[0044] In some preferred embodiments of the present invention, the adhesion promoter is selected from alkyl acrylate phosphates and / or methacryloxy silanes.

[0045] In the present invention, preferably, the bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group has a long carbon chain and the main chain carbon number of the carbon chain is 4-17. Under this preferred embodiment, the bifunctional polyurethane acrylate resin has better flexibility, which is more conducive to enhancing the durability of the material and improving the processing performance. Exemplarily, the bifunctional polyurethane acrylate resin can be polyurethane acrylate resin (91410) and the like. Polyurethane acrylate resin can be obtained commercially, for example, from Guangzhou Haohui New Materials Co., Ltd., Arkema Group (Sartomer) or Changxing Materials Industry Co., Ltd.; it can also be prepared by existing methods.

[0046] In a second aspect, the present invention provides a method for preparing a toughened UV moisture dual curing conformal coating, which is used to prepare the toughened UV moisture dual curing conformal coating described in the first aspect, and the preparation method comprises the following steps:

[0047] S1, first mixing required amounts of tricyclodecane dimethanol diacrylate, a toughening regulator, and a bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group to obtain a first mixed solution;

[0048] S2, introducing a photoinitiator into the first mixed solution for a second mixing to obtain a second mixed solution;

[0049] S3. Then degassing is performed under vacuum conditions.

[0050] The present invention adopts the above-mentioned specific mixing steps, which can ensure the steady progress of the reaction and improve the mixing uniformity compared to the method of mixing all the raw materials together; combined with vacuum degassing, it can effectively remove bubbles in the material, which is beneficial to improving the stability and efficiency of the process production, and can significantly reduce wrinkling, cracking, insufficient adhesion and other problems caused by system shrinkage, and has higher tensile strength and lower water vapor permeability.

[0051] In some preferred embodiments of the present invention, the preparation method further comprises: introducing a free radical inhibitor and a fluorescent brightener into the second mixing in S2, then introducing a catalytic moisture curing agent and / or an adhesion promoter into the obtained second mixed liquid for a third mixing to obtain a third mixed liquid, and then degassing the third mixed liquid in S3. This preferred specific mixing step, compared to mixing all raw materials together, can ensure a steady reaction, is more conducive to improving mixing uniformity, enhances material properties such as toughness and tensile strength, and reduces water vapor transmission.

[0052] In some preferred embodiments of the present invention, the conditions for the first mixing include: a stirring speed of 1500-2300 rpm, and a stirring time of 100-150 s.

[0053] In some preferred embodiments of the present invention, the second mixing conditions include: a stirring speed of 2100-2500 rpm, and a stirring time of 150-200 s.

[0054] In some preferred embodiments of the present invention, the conditions for the third mixing include: a stirring speed of 1500-2000 rpm, and a stirring time of 50-100 s.

[0055] In some preferred embodiments of the present invention, the degassing time is 1-3 minutes.

[0056] Adopting the above-mentioned mixing conditions and / or degassing conditions of the present invention can improve the uniformity of the material and facilitate the smooth progress of the process.

[0057] The embodiments of the present invention are described in detail below, which are exemplary and only used to explain the present invention, and are not to be construed as limiting the present invention.

[0058] Example 1

[0059] Table 1 shows the raw material formula for a conformal coating. The toughening modifier is bisacryloxy-modified polyisobutylene (purchased from Kaneka Corporation, model EP400V). The calculated weight ratio of tricyclodecane dimethanol diacrylate to the toughening modifier is 100:15.34.

[0060] Table 1

[0061]

[0062] The preparation method comprises the following steps:

[0063] 1. Mix DCPDA, toughening regulator and 91410 twice in a mixer (mixing speed 2000 rpm, mixing for a total of 150 seconds).

[0064] 2. Add photoinitiator 184, BHT, and UV-OB to the mixture obtained in step 1 and mix three times under a mixer (mixing speed 2000 rpm, total mixing 150 s).

[0065] 3. Add DMDEE to the mixture obtained in step 2 and mix once under a mixer (mixing speed 2000 rpm, mixing for a total of 150 seconds).

[0066] 4. Degas the mixture obtained in step 3 under vacuum conditions for 1 min.

[0067] Example 2

[0068] The method of Example 1 was referred to, except that the toughening regulator was diene-containing EPDM rubber (purchased from Lion Chemical Company, USA, model number: Trilene 65) with a molecular weight of 7500 Da, and the amount used remained unchanged.

[0069] Example 3

[0070] The method of Example 1 was followed, except that the toughening regulator was a carboxyl-terminated liquid nitrile rubber (purchased from Tianyuan Aerospace Materials Technology Co., Ltd., model TY-CTBN-20), which had a long carbon chain and the main chain carbon number of the carbon chain was 12, and the amount used remained unchanged.

[0071] Example 4

[0072] The method of Example 1 was referred to, except that the amount of the toughening modifier was adjusted so that the weight ratio of tricyclodecane dimethanol diacrylate to the toughening modifier was 100:10.

[0073] Example 5

[0074] The method of Example 1 was followed, except that degassing was not performed.

[0075] Comparative Example 1

[0076] The method of Example 1 was used, except that no toughening agent was added.

[0077] Comparative Example 2

[0078] The method of Example 1 was referred to, except that the amount of the toughening modifier was adjusted so that the weight ratio of tricyclodecane dimethanol diacrylate to the toughening modifier was 100:30.

[0079] Comparative Example 3

[0080] The method of Example 1 was used, except that tricyclodecane dimethanol diacrylate was replaced by isobornyl acrylate, and the amount used remained unchanged.

[0081] Test Case

[0082] The conformal coatings obtained in the above examples and comparative examples were subjected to performance testing, with the results shown in Table 2. Wrinkling and cracking were measured by curing the conformal coating onto a stainless steel sheet to form a 50-micron thick film. The stainless steel sheet was then bent 90° and observed for wrinkling and cracking. Cracking was categorized into three levels: no cracking, slight cracking, and cracking. The quantitative distinction between slight cracking and cracking was determined as follows: short, isolated cracks with minimal impact on the overall conformal coating film structure were considered slight cracking; multiple cracks affecting the overall conformal coating film structure were considered cracking; and no cracking was considered no cracking. Adhesion was measured and graded according to GB / T 9286-2021. Tensile strength was measured by curing the conformal coating into a 25-micron thick film using a microcomputer-controlled electronic universal testing machine (purchased from Shenzhen Sansi Zongheng Technology Co., Ltd., model: UTM4503HA). Water vapor transmission rate was measured according to GB / T 1037-2021.

[0083] Table 2

[0084]

[0085] The above results show that, compared with the comparative example, the embodiment of the present invention is less likely to break when subjected to external force, and has excellent adhesion, can significantly reduce problems such as wrinkling, cracking, and insufficient adhesion caused by system shrinkage, and has higher tensile strength and lower water vapor permeability.

[0086] Furthermore, according to Example 1 and Examples 2-5, it can be seen that the preferred solution of the present invention is more conducive to improving adhesion, obtaining higher tensile strength and lower water vapor permeability.

[0087] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A toughened UV moisture dual curing conformal coating, characterized in that: The invention comprises the following raw material components in the following weight percentages: based on the total amount of raw materials, 39-84 wt% of tricyclodecane dimethanol diacrylate, 13-45 wt% of a bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group, 2-10 wt% of a toughening regulator, and 1-6 wt% of a photoinitiator; the weight ratio of the tricyclodecane dimethanol diacrylate to the toughening regulator is 100:(2.38-25.60); wherein the toughening regulator is selected from bisacryloyloxy-modified polyisobutylene.

2. The toughened UV moisture dual curing conformal coating according to claim 1, characterized in that: The toughening modifier has a long carbon chain and the main chain carbon atoms of the carbon chain are 5-20.

3. The toughened UV moisture dual curing conformal coating according to claim 1, characterized in that: The bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group has a long carbon chain, and the main chain carbon atoms of the carbon chain are 4-17.

4. The toughened UV moisture dual curing conformal coating according to claim 1, characterized in that: The raw material components of the toughened UV moisture dual-curing conformal paint further include at least one auxiliary agent selected from the group consisting of a catalytic moisture curing agent, a free radical inhibitor, a fluorescent brightener, and an adhesion promoter.

5. The toughened UV moisture dual curing conformal coating according to claim 4, characterized in that: The raw material components of the toughened UV moisture dual-curing conformal paint include: based on the total amount of raw materials, 0-0.4 wt% of a catalytic moisture curing agent, 0.03-0.07 wt% of a free radical inhibitor, 0.01-0.03 wt% of a fluorescent brightener, and 0-1.5 wt% of an adhesion promoter.

6. The toughened UV moisture dual curing conformal coating according to claim 4, characterized in that: Catalytic moisture curing agent is selected from 、 , DMDEE; and / or, The free radical inhibitor is selected from 、 、 、 、 、 wherein R and R1 are each independently selected from an alkyl group having 4 to 8 carbon atoms.

7. The toughened UV moisture dual curing conformal coating according to claim 4, characterized in that: Fluorescent whitening agent selected from C 26 H 26 N2O2S、C 24 H 14 O2N2、C 28 H 18 N2O2、C 30 H 26 O2 at least one; and / or, the adhesion promoter is selected from alkyl acrylate phosphate and / or methacryloxy silane.

8. A method for preparing a toughened UV moisture dual-curing conformal coating, characterized in that: The invention is used to prepare the toughened UV moisture dual-curing conformal coating according to any one of claims 1 to 7, and the preparation method thereof comprises the following steps: S1, first mixing required amounts of tricyclodecane dimethanol diacrylate, a toughening regulator, and a bifunctional polyurethane acrylate resin containing an acryloyl group and an isocyanate group to obtain a first mixed solution; S2, introducing a photoinitiator into the first mixed solution for a second mixing to obtain a second mixed solution; S3. Then degassing is performed under vacuum conditions.

9. The method for preparing the toughened UV moisture dual-curing conformal coating according to claim 8, characterized in that: The preparation method further includes: introducing a free radical inhibitor and a fluorescent whitening agent into the second mixture in S2, then introducing a catalytic moisture curing agent and / or an adhesion promoter into the obtained second mixed liquid for a third mixing to obtain a third mixed liquid, and then degassing the third mixed liquid in S3.

10. The method for preparing the toughened UV moisture dual curing conformal coating according to claim 9, characterized in that: The first mixing conditions include: a stirring speed of 1500-2300 rpm and a stirring time of 100-150 s; The second mixing conditions include: stirring speed of 2100-2500 rpm, stirring time of 150-200 s; The third mixing conditions include: stirring speed of 1500-2000 rpm, stirring time of 50-100 s; The degassing time is 1-3 minutes.

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