Moisture-resistant water-based pre-coating glue and preparation method thereof

Abstract

The invention relates to the field of pre-coating glue, in particular to moisture-resistant pre-coating glue and a preparation method thereof. The moisture-resistant water-based pre-coating adhesive provided by the invention is prepared from the following substances in parts by mass: a component A: 30 to 60 parts of purified water, 0.5 to 2 parts of an anti-freezing agent, 2 to 10 parts of an emulsifying film-forming agent, 0.1 to 1.0 part of an emulsifying salt-forming aid, 1.0 to 5.0 parts of a film-forming aid, 30 to 50 parts of an acrylate monomer, 5 to 20 parts of a grinding aid, 0.1 to 2 parts of a red pigment and 0.01 to 1.0 part of a curing reaction accelerant; and the component B comprises 2-5 parts of a BPO microcapsule initiator. Meanwhile, the invention provides a preparation method, and the prepared adhesive is a water-based pre-coating adhesive coating, is coated on a bolt, and is used for locking the bolt after being dried. According to the technology, the precoated coating can be stably stored in a high-humidity environment after being dried, and the problems that an existing water-based precoated coating is sensitive to moisture, so that reactive liquid raw materials in the coating seep and flow, and seriously, the coating cannot be cured are solved.

Description

Technical Field

[0001] This invention relates to the field of pre-coated threadlocking adhesive technology, and more particularly to a moisture-resistant water-based pre-coated adhesive and its preparation method. Background Technology

[0002] To prevent bolts from loosening and causing connection failure, bolt-locking adhesive is typically used to strengthen the bolts and reduce loosening caused by vibration and external forces. Currently, there are two types of thread-locking adhesives on the market: online-applied liquid anaerobic acrylic thread-locking adhesive and pre-applied thread-locking adhesive. The advantage of pre-applied anaerobic adhesive is that it eliminates the need for on-site application when tightening bolts. This avoids adhesive contamination of the assembly area, reduces locking performance defects caused by variations in human application, and improves bolt assembly and locking efficiency. Therefore, pre-applied bolt adhesive is particularly suitable for automated assembly line operations and is increasingly widely used.

[0003] There are two main types of pre-coated bolt locking adhesives on the market: water-based and solvent-based. Solvent-based pre-coats almost always use toluene as a solvent, which is highly hazardous. Even if some products use non-toluene solvents, their performance still doesn't reach the level of conventional solvent-based pre-coats, and their VOC emissions are also high, making them environmentally unfriendly. Water-based pre-coats are safe and environmentally friendly, and under current environmental requirements, they are highly recommended for widespread promotion; related products have been on the market for a long time. However, the biggest problem with water-based pre-coats is that the dried coating is extremely sensitive to moisture. When the coating gets damp, it is damaged, and reactive liquid materials seep out, contaminating bolts and assembled components. In severe cases, the coating may fail to cure, losing its locking and sealing functions. To avoid the coating being affected by moisture, water-based pre-coats must be sealed in airtight bags as soon as possible after application and drying. Even with such sealing, the coating will inevitably absorb moisture after prolonged storage, affecting its performance and requiring rework if necessary. The sealing process requirements and the uncertainty of performance after storage bring many unnecessary troubles and risks to the production and assembly of enterprises.

[0004] The water-based pre-coated threadlocking adhesive comprises four main components: reactive liquid acrylate monomers, an emulsifying film-forming agent, water, and a BPO microcapsule initiator. The emulsifying film-forming agent emulsifies and encapsulates the reactive liquid acrylate monomers into tiny liquid capsules in the aqueous phase. During the high-temperature drying process, the coating applied to the bolts allows the emulsifying film-forming agent to dry and form a film on the surface of the reactive liquid acrylate droplets, creating a robust shell and thus forming a solid honeycomb structure coating on the thread surface. This structure allows the liquid raw materials to remain stable within the coating. When the nut and bolt are assembled, the friction generated by the screwing in breaks the honeycomb structure and BPO microcapsules, initiating a free radical polymerization reaction of the liquid acrylate monomers, thus tightly securing and sealing the nut and bolt.

[0005] CN118085796A relates to a high-toughness, impact-resistant pre-coated anaerobic adhesive and its preparation method. It includes an adhesive liquid and curing initiator microcapsules mixed during pre-coating. The adhesive liquid is an emulsion formed by dispersing an anaerobic adhesive monomer composition in an adhesive solution. The curing initiator microcapsules are microcapsules made of urea-formaldehyde resin polymer coated with organic peroxides. By introducing polyurethane acrylate monomers and an impact modifier into the pre-coated anaerobic adhesive, the cured adhesive exhibits the high adhesion and flexibility of polyurethane. The impact modifier is uniformly dispersed in the resin in particulate form, forming an island structure with the resin. When subjected to external force, numerous crazing forms around the particles, rapidly spreading to form many shear bands, absorbing a large amount of impact energy, thereby greatly improving the impact resistance of the adhesive layer. This successfully solves the problems of brittle adhesive layers and poor impact resistance in pre-coated anaerobic adhesives, expanding the application range of pre-coated anaerobic adhesives.

[0006] CN102115640B provides a single-component pre-coated anaerobic adhesive and its preparation method. It belongs to the technical field of pre-coated anaerobic adhesives. It mainly solves the problems of instability and uneven mixing in existing two-component pre-coated anaerobic adhesives. Its main features are: containing: (A) 35%–50 wt% unsaturated monomers containing at least one vinyl terminator; (B) 35%–60 wt% water; (C) 3–10 wt% water-soluble thickener; (E) 0.01%–3 wt% polymerization accelerator; (F) 0.5%–2 wt% pigment; (G) 3%–15 wt% filler; (H) 1%–5 wt% film-forming aid; and (I) 0.5%–5 wt% microencapsulation initiator. Method: Add (A), (B), and (C) to the reactor and stir until homogeneous; add (E), (F), and (G) and stir until homogeneous; add (H) and stir; add (I) and stir at low speed until (I) is homogeneous; evacuate to approximately 0.09 MPa; package and store away from light. The provided pre-coating has the characteristics of being a single component and is widely used in the locking and sealing of various threaded fasteners in the machinery industry.

[0007] However, both water-soluble polymer copolymers and soluble metal salt solutions exhibit strong hydrophilicity. They dissolve in water before film formation and readily absorb water after film formation, leading to the destruction of the honeycomb structure by water dissolution. When defects appear in the coating structure, liquid acrylate monomers will seep out and flow from these defects, potentially causing ineffective curing and locking failure after bolt assembly. Therefore, improving the water resistance of water-based pre-coated coatings requires addressing the hydrophilicity of the emulsifying film-forming agent.

[0008] The purpose of this invention is to provide a method for reducing the sensitivity of water-based pre-coatings to environmental humidity, improving the storage stability of the coating, solving a series of failure problems caused by moisture absorption of existing water-based pre-coatings, and reducing the losses caused to enterprises. Summary of the Invention

[0009] The purpose of this invention is to provide a method to solve the problem of seepage and flow of reactive liquid raw materials in water-based pre-coated adhesive coatings stored in high-humidity environments. This method retains the emulsifying ability of the emulsion while improving the water resistance of the dried film coating, thereby preparing a water-based thread-locking pre-coated adhesive that is insensitive to moisture.

[0010] A moisture-resistant water-based pre-coating adhesive comprises the following components in parts by weight:

[0011] Component A:

[0012] 30-60 parts purified water

[0013] Antifreeze 0.5 to 2 parts

[0014] 2-10 parts of emulsifying film-forming agent

[0015] Emulsifying salt-forming aid: 0.1–1.0 parts

[0016] Film-forming aid 1.0–5.0 parts

[0017] 30-50 parts of acrylate monomer

[0018] 5-20 parts of grinding aid

[0019] 0.1 to 2 parts of red pigment

[0020] Curing reaction accelerator 0.01-1.0 parts;

[0021] Component B:

[0022] 2-5 parts of BPO (benzoyl peroxide) microcapsule initiator.

[0023] BPO (benzoyl peroxide) microcapsules are broken by the friction generated when the nut is screwed into the bolt during assembly, releasing benzoyl peroxide and initiating a free radical polymerization reaction of liquid acrylate monomers.

[0024] Furthermore, the antifreeze is at least one of ethylene glycol and propylene glycol.

[0025] Further, the emulsifying film-forming agent is a mixture of 7 wt% acrylic emulsion, hydroxyl-terminated polydimethylsiloxane, and tridecafluorooctyltriethoxysilane. The mass of hydroxyl-terminated polydimethylsiloxane is 0-30 wt% of the mixture, and the mass of tridecafluorooctyltriethoxysilane is 0-30 wt% of the mixture. The organosilicon groups of the hydroxyl-terminated polydimethylsiloxane migrate to the surface to form a dynamic hydrophobic layer, improving the hydrophobic properties of the product. Tridecafluorooctyltriethoxysilane has a low surface free energy, resulting in its anti-sticking properties to both polar and non-polar substances. Its carbon-fluorine bonds have excellent stability against humid atmospheres. POTS hydrolyzes in a humid environment to form a silica-based film and a self-healing anti-corrosion polymer. This film is synthesized through a hydrolytic polymerization condensation reaction of POTS and water and possesses natural hydrophobicity. This wettability can separate the electrolyte aqueous solution from the metal substrate, thereby providing corrosion protection for the metal substrate.

[0026] Furthermore, the emulsifying salt-forming aid is at least one of ammonia, ammonium bicarbonate, ammonium dihydrogen phosphate, and ammonium hydrogen sulfate. It provides an alkaline substance containing volatile amines, which reacts with the emulsifying film-forming agent to generate a water-soluble macromolecular ammonium salt, thereby improving its water solubility and emulsifying ability.

[0027] Furthermore, the grinding aid is at least one selected from silica, kaolin, mica powder, and silica. The grinding aid helps disperse and mix other components, improving the uniformity and stability of the adhesive.

[0028] Furthermore, the acrylate monomer is at least one selected from bisphenol A dimethacrylate and 2,2-bis[4-(isobutenoyloxyethoxy)phenyl]propane. The acrylate monomer is the main component undergoing free radical polymerization, and during the assembly of the nut and bolt, it is initiated to polymerize, achieving bolt locking and sealing.

[0029] Furthermore, the film-forming aid is at least one selected from zinc methacrylate, zinc acrylate, zinc stearate, magnesium stearate, calcium stearate, nano-calcium carbonate, and nano-magnesium carbonate. The liquid acrylate microparticles of the film-forming aid form a solid film on their surface, promoting coating formation.

[0030] Furthermore, the red pigment is at least one of 3902 oil-soluble red and pigment permanent red F4R. The red pigment is used to identify adhesives for ease of identification and quality control.

[0031] Furthermore, the curing reaction accelerator is ferrocene.

[0032] The present invention also provides a method for preparing the moisture-resistant water-based pre-coating adhesive described above, comprising the following steps:

[0033] Preparation of component A

[0034] S11. Add the acrylate monomer, grinding aid, red pigment, and curing accelerator to the mixing tank, and stir at high speed for 30-60 minutes at room temperature until homogeneous. Then, stir under vacuum to remove bubbles.

[0035] After stirring for 5-10 minutes, remove and set aside.

[0036] S12. Add purified water, antifreeze, and emulsifying film-forming agent into the reaction vessel, stir at low speed for 10-30 minutes at room temperature until they are mixed evenly, then slowly add the emulsifying salt-forming aid dropwise while stirring, and stir rapidly for 60-90 minutes to allow the emulsifying film-forming agent and the emulsifying salt-forming aid to react fully, and finally add the film-forming aid and stir rapidly for 10-30 minutes to disperse evenly;

[0037] S13. Slowly add the mixture prepared in S11 to the mixture prepared in S12 while stirring. After the addition is complete, continue stirring for 30-60 minutes until the mixture is uniform. Vacuum stir the mixed material to remove air bubbles, then pack it into packaging barrels and store it away from light for later use.

[0038] Preparation of component B

[0039] S21. Preparation of capsule prepolymer: 1.5 parts of 4,4'-dihydroxybiphenyl and 5 parts of hexamethylene diisocyanate were dissolved in 10 parts of acetone, and 0.05 parts of dibutyltin dilaurate were added. The mixture was reacted at 60°C for 3 hours to obtain the prepolymer.

[0040] S22. Microcapsule encapsulation: Mix 10 parts of BPO with the capsule prepolymer, emulsify in a 2wt% polyvinyl alcohol aqueous solution, add 0.5 parts of ethylenediamine, stir and cure at 45°C for 6 hours to obtain BPO microcapsule initiator.

[0041] This invention improves the water resistance of water-based pre-coated adhesive coatings by enhancing the hydrophilicity of the emulsifying film-forming agent. Specifically, ammonia or water-soluble ammonium salts react with the carboxyl-containing emulsifying film-forming agent to generate a water-soluble macromolecular ammonium salt, improving its water solubility and giving it excellent emulsifying ability. This allows the liquid acrylate monomers to be emulsified and dispersed in the aqueous phase, forming a stable oil-in-water structure in the pre-coated adhesive. After the pre-coated adhesive is applied to the bolts, during the heating and drying process, the emulsifying film-forming agent in the aqueous phase, with the assistance of film-forming aids, forms a solid film on the surface of the liquid acrylate particles, thereby forming a honeycomb structure coating. The key point is that the macromolecular ammonium salt generated by the emulsifying film-forming agent is a weak acid-weak base salt. Under the influence of the film-forming aids, it can decompose at high temperatures to release ammonia gas, and its salt properties disappear, causing the coating to change from hydrophilic to hydrophobic. The hydrophobic coating will not be dissolved or destroyed by water, and the liquid acrylate monomers in the honeycomb structure will not seep out or flow, thus achieving stable storage in high humidity environments.

[0042] The advantages of the product prepared by this invention are as follows:

[0043] (1) Reduced packaging costs and workload: The moisture-resistant pre-coated adhesive coating obtained by this invention makes the pre-coated bolt coating insensitive to moisture. After the coating dries, there is no need for strict sealing and moisture-proofing treatment. Even if a small amount of moisture is absorbed, it will not have a serious impact on the coating. This greatly reduces the packaging workload and production costs for pre-coated parts manufacturers.

[0044] (2) Improve storage stability and safety: This invention ensures the storage stability of the coating, reduces product failure caused by unstrict storage conditions, helps reduce the failure rate caused by loose or falling bolts on machinery and vehicles, and reduces or eliminates safety hazards to industrial production and daily life.

[0045] (3) Improve the consistency of bolt locking strength: By improving the hydrophilicity of the coating, the structural strength of the coating is stabilized, which can improve the fluctuation of bolt locking strength data caused by coating defects and improve the consistency of bolt locking strength.

[0046] (4) Reduce rework costs: This invention eliminates the increased production costs caused by the need to reheat and dry or completely remove and reapply the coating after the bolt coating prepared by commercial products gets damp. It avoids rework problems caused by the coating getting damp and reduces the economic losses of enterprises.

[0047] (5) Provide technical reference: The technology adopted in this invention breaks through the traditional mindset that the erroneous view that good hydrophilicity of emulsion means poor water resistance of coating, and provides reference for other similar technical issues. Detailed Implementation

[0048] 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.

[0049] Example 1

[0050] A moisture-resistant water-based pre-coating adhesive comprises the following components in parts by weight.

[0051] Component A:

[0052] 40kg of purified water

[0053] 1 kg of ethylene glycol

[0054] 4kg of emulsifying film-forming agent

[0055] 0.3 kg of ammonia water

[0056] 2kg magnesium stearate

[0057] 2,2-Bis[4-(isobutenoyloxyethoxy)phenyl]propane 40kg

[0058] 8kg of silicon dioxide

[0059] Permanent Red F4R 0.2kg

[0060] 0.3 kg of ferrocene;

[0061] Component B:

[0062] 2.5 kg of BPO microcapsule initiator.

[0063] The emulsifying film-forming agent is 4 kg of 7 wt% acrylic emulsion.

[0064] The preparation method of the above-mentioned moisture-resistant water-based pre-coating adhesive includes the following steps:

[0065] Preparation of component A

[0066] S11. Add acrylate monomer, grinding aid, red pigment and curing reaction accelerator to a mixing tank, stir at high speed at room temperature for 40 minutes to mix evenly, then stir under vacuum to remove bubbles for 10 minutes. After stirring, take it out for later use.

[0067] S12. Add purified water, antifreeze, and emulsifying film-forming agent into the reaction vessel, stir at low speed for 20 minutes at room temperature until they are evenly mixed, then slowly add the emulsifying salt-forming aid dropwise while stirring, and stir rapidly for 80 minutes to allow the emulsifying film-forming agent and the emulsifying salt-forming aid to react fully. Finally, add the film-forming aid and stir rapidly for 20 minutes to disperse evenly.

[0068] S13. Slowly add the mixture prepared in S11 to the mixture prepared in S12 while stirring. After the addition is complete, continue stirring for 40 minutes until the mixture is uniform. Vacuum stir the mixed material to remove air bubbles, then pack it into packaging barrels and store it away from light for later use.

[0069] Preparation of component B

[0070] S21. Preparation of capsule prepolymer: Dissolve 1.5 kg of 4,4'-dihydroxybiphenyl and 5 kg of hexamethylene diisocyanate in 10 kg of acetone, add 0.05 kg of dibutyltin dilaurate, and react at 60 °C for 3 h to obtain the prepolymer; S22. Microcapsule encapsulation: Mix 10 kg of BPO with the capsule prepolymer, emulsify in 2 wt% polyvinyl alcohol aqueous solution, add 0.5 kg of ethylenediamine, and stir and solidify at 45 °C for 6 h to obtain BPO microcapsule initiator.

[0071] Example 2

[0072] A moisture-resistant water-based pre-coating adhesive comprises the following components in parts by weight.

[0073] Component A:

[0074] 40kg of purified water

[0075] 1 kg of propylene glycol

[0076] 4kg of emulsifying film-forming agent

[0077] 0.3 kg of ammonium bicarbonate

[0078] 2kg of zinc acrylate

[0079] 40kg of Bisphenol A dimethacrylate

[0080] 8kg of silicon dioxide

[0081] 3902 Oil-soluble Red 0.2kg

[0082] 0.3 kg of ferrocene;

[0083] Component B:

[0084] 2.5 kg of BPO microcapsule initiator.

[0085] The emulsifying film-forming agent is a mixture of 3 kg of 7 wt% acrylic emulsion and 1 kg of hydroxyl-terminated polydimethylsiloxane.

[0086] The preparation methods for components A and B are the same as in Example 1.

[0087] Example 3

[0088] A moisture-resistant water-based pre-coating adhesive comprises the following components in parts by weight.

[0089] Component A:

[0090] 50kg of purified water

[0091] 2kg of propylene glycol

[0092] 4kg of emulsifying film-forming agent

[0093] Ammonium bisulfate 0.5 kg

[0094] 5kg of nano magnesium carbonate

[0095] 45kg of Bisphenol A dimethacrylate

[0096] 8kg of silica

[0097] 3902 Oil-soluble Red 0.4kg

[0098] 0.5 kg of ferrocene;

[0099] Component B:

[0100] 3 kg of BPO microcapsule initiator.

[0101] The emulsifying film-forming agent is a mixture of 2.5 kg of 7 wt% acrylic emulsion, 0.8 kg of hydroxyl-terminated polydimethylsiloxane, and 0.7 kg of tridecafluorooctyltriethoxysilane.

[0102] The preparation methods for components A and B are the same as in Example 1.

[0103] Comparative Example 1

[0104] The only difference is that the ammonia in Example 1 is replaced with sodium hydroxide; otherwise, it is the same as in Example 1 and will not be repeated.

[0105] Comparative Example 2

[0106] The only difference is that the magnesium stearate component, the film-forming aid in Example 1, is removed; otherwise, it is the same as in Example 1 and will not be repeated.

[0107] The pre-coated parts were prepared by applying the pre-coated adhesive prepared in the examples and comparative examples to the bolts. The specific method was as follows: after mixing component A and component B, the mixture was evenly applied to the 8.8 grade color zinc plated bolts, and then placed in an 80°C forced-air drying oven for 30 minutes. After being taken out and cooled to room temperature, the parts were tested.

[0108] Storage stability test:

[0109] Humid heat aging: The prepared pre-coated bolts are placed vertically in a 90% humidity, 40℃ humid heat aging chamber. After a predetermined time, they are taken out, cooled to room temperature, and the coating condition is observed.

[0110] Water immersion test: The prepared pre-coated bolts were immersed in water for a predetermined time, and the coating condition was observed. The test results are shown in Table 1. Table 1

[0111]

[0112] Performance testing:

[0113] Failure torque: Tested according to the requirements of GB / T35480-2017 Technical Conditions for Pre-coated Microcapsule Adhesive Layers for Fasteners, Bolts, Screws and Studs. Test results are shown in Table 2.

[0114] Table 2

[0115]

[0116] As shown in Table 1, under the same raw materials and composition ratios, the coatings of the Examples and Comparative Examples exhibit significant differences in their resistance to damp heat and water immersion stability. The pre-coated coatings showed no significant difference in their dried state, but their properties changed considerably under both humid and water immersion conditions. Examples 1, 2, and 3 showed no significant changes in coating state or integrity regardless of whether they were placed in a 90% humidity environment or immersed in water. Comparative Examples 1 and 2, under 90% humidity, showed significant liquid precipitation after 3 days, and after 7 days, a large amount of reactive liquid raw material precipitated from the coating and flowed to the bottom of the bolt. The differences in water immersion were more pronounced between the Comparative Examples and the Examples; the coatings of the Comparative Examples eventually broke down and dissolved in the water.

[0117] As shown in Table 2, the locking ability of the coatings in the examples and comparative examples decreased sharply after being stored in high humidity environments for different periods. After 3 days of storage in a 90% humidity environment, the locking strength of the comparative example had already decreased to 12-13 N·m, which is the minimum value for bolt locking standards. In particular, after 7 days, it had no locking ability at all. The problem of reactive liquid acrylate monomer precipitation and flow occurred even before assembly, resulting in a reduction in the actual coating thickness. During nut and bolt assembly, the contact area between the nut thread and the coating on the bolt was reduced, and the friction was far from sufficient to break the BPO microcapsules, thus failing to induce effective coating curing. Therefore, the integrity of the honeycomb structure of the coating composed of the emulsifying film-forming agent is a necessary factor for maintaining locking strength.

[0118] The emulsifying salt-forming agent and film-forming agent used in this invention work together to ensure the water resistance stability of the coating structure, successfully achieving stable storage of the water-based pre-coated adhesive coating in a high-humidity environment, reducing the use risk and cost of water-based thread pre-coated adhesive, and expanding the application range of water-based pre-coated adhesive.

Claims

1. A moisture-resistant water-based pre-coating adhesive, characterized in that, The composition includes the following parts by mass: Component A: 30-60 parts purified water Antifreeze 0.5 to 2 parts 2-10 parts of emulsifying film-forming agent Emulsifying salt-forming aid: 0.1–1.0 parts Film-forming aid 1.0–5.0 parts 30-50 parts of acrylate monomer 5-20 parts of grinding aid 0.1 to 2 parts of red pigment Curing reaction accelerator 0.01-1.0 parts; Component B: 2-5 parts of BPO microcapsule initiator.

2. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The antifreeze is at least one of ethylene glycol and propylene glycol.

3. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The emulsifying film-forming agent is a mixture of 7 wt% acrylic emulsion, hydroxyl-terminated polydimethylsiloxane, and tridecafluorooctyltriethoxysilane (i.e., perfluorooctyltriethoxysilane). The mass of hydroxyl-terminated polydimethylsiloxane and tridecafluorooctyltriethoxysilane is 0–30 wt% of the mixture. In a humid environment, the organosilicon component migrates to the surface to form a dynamic hydrophobic layer, improving moisture resistance. Tridecafluorooctyltriethoxysilane promotes the formation of a superhydrophobic coating, enhancing product performance.

4. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The emulsifying salt-forming aid is at least one of ammonia, ammonium bicarbonate, ammonium dihydrogen phosphate, and ammonium hydrogen sulfate.

5. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The grinding aid is at least one of silicon dioxide, kaolin, mica powder, and silica.

6. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The acrylate monomer is at least one of bisphenol A dimethacrylate and 2,2-bis[4-(isobutenoyloxyethoxy)phenyl]propane.

7. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The film-forming aid is at least one of zinc methacrylate, zinc acrylate, zinc stearate, magnesium stearate, calcium stearate, nano calcium carbonate, and nano magnesium carbonate.

8. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The red pigment is at least one of 3902 oil-soluble red and pigment permanent red F4R.

9. The moisture-resistant water-based pre-coating adhesive according to claim 1, characterized in that, The curing reaction accelerator is ferrocene.

10. A method for preparing a moisture-resistant water-based pre-coating adhesive according to any one of claims 1 to 9, characterized in that, Includes the following steps: Preparation of component A S11. Add acrylate monomer, grinding aid, red pigment and curing reaction accelerator to a mixing tank, stir at high speed at room temperature for 30-60 minutes until uniformly mixed, then stir under vacuum to remove bubbles for 5-10 minutes. After stirring, remove and set aside. S12. Add purified water, antifreeze, and emulsifying film-forming agent into the reaction vessel, stir at low speed for 10-30 minutes at room temperature until they are mixed evenly, then slowly add the emulsifying salt-forming aid dropwise while stirring, and stir rapidly for 60-90 minutes to allow the emulsifying film-forming agent and the emulsifying salt-forming aid to react fully, and finally add the film-forming aid and stir rapidly for 10-30 minutes to disperse evenly; S13. Slowly add the mixture prepared in S11 to the mixture prepared in S12 while stirring. After the addition is complete, continue stirring for 30-60 minutes until the mixture is uniform. Vacuum stir the mixed material to remove air bubbles, then pack it into packaging barrels and store it away from light for later use. Preparation of component B S21. Preparation of capsule prepolymer: 1.5 parts of 4,4'-dihydroxybiphenyl and 5 parts of hexamethylene diisocyanate were dissolved in 10 parts of acetone, and 0.05 parts of dibutyltin dilaurate were added. The mixture was reacted at 60°C for 3 hours to obtain the prepolymer. S22. Microcapsule encapsulation: Mix 10 parts of BPO with the capsule prepolymer, emulsify in a 2wt% polyvinyl alcohol aqueous solution, add 0.5 parts of ethylenediamine, stir and cure at 45°C for 6 hours to obtain BPO microcapsule initiator.

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