A cationic high-solid acrylic resin, its preparation method, a marine antifouling coating and its preparation method

Abstract

The present invention provides a cationic high-solid acrylic resin, its preparation method, a marine antifouling coating and its preparation method. First, a cationic high-solid acrylic resin with hydroxyl groups is synthesized, and cationic groups with antibacterial effects are introduced into the polymer network through the quaternization of dimethylaminoethyl acrylate. Then, dendritic polyester polyol is added to increase the density of the polymer three-dimensional network, thereby endowing the coating with excellent mechanical properties and anticorrosion properties. Finally, an aliphatic polyurethane oligomer is used as a curing agent, and after curing, a marine antifouling coating with excellent antibacterial properties, low surface energy and weather resistance is obtained. The coating has a significant effect on preventing the adhesion of marine microorganisms, is particularly suitable for protecting the surfaces of offshore platforms, ships and large marine equipment, is more environmentally friendly, and meets the national energy conservation and carbon reduction strategic requirements and the concept of marine protection.

Description

Technical Field

[0001] The present invention belongs to the technical field of marine antifouling coatings, and specifically relates to a cationic high-solid-content acrylic resin and a preparation method thereof, and also relates to a marine antifouling coating containing the cationic high-solid-content acrylic resin and a preparation method thereof. Background Art

[0002] Offshore equipment has to cope with complex climatic environments and withstand the corrosion of marine microorganisms. The adhesion and proliferation of microorganisms will accelerate the corrosion of offshore platforms, ports, and submarine pipelines. Moreover, when microorganisms adhere to the surface of ships, it will increase the navigation energy consumption, which does not conform to the carbon emission reduction strategy. With the continuous improvement of China's marine strategic position, higher requirements have been put forward for the protection of offshore equipment. Traditional marine antifouling coatings have been banned because they contain harmful substances such as organotin and cause great harm to the marine environment. Most of the newly developed environmentally friendly marine antifouling coatings also require a considerable proportion of organic solvents for use, still having a great impact on the environment.

[0003] To solve this problem, high-solid-content coatings have emerged. Their solid component content is relatively high, usually above 50%, so the emissions of volatile organic compounds, that is, VOC, are very low. At the same time, their viscosity is relatively low, making them easy to flow and construct, and can obtain a smooth and flat coating, improving the covering power, adhesion, and durability of the coating. In marine antifouling coatings, the application of this resin can significantly improve the adhesion and durability of the coating. In addition, due to the corrosiveness and biological adhesion problems in the marine environment, the high-solid-content resin can form a stronger protective layer to resist seawater erosion and the adhesion of marine organisms, thereby extending the service life of the coating and reducing maintenance costs.

[0004] Acrylic resin has strong adhesion and ultraviolet resistance, and at the same time has the characteristics of abrasion resistance, corrosion resistance, and anti-algae growth. It has a wide range of applications and is an important raw material for preparing marine antifouling coatings, especially suitable for offshore drilling platforms and marine engineering structures. However, it mainly plays a role in film formation and controlling the release of antifouling agents in the coating. When used alone as a marine coating, it has no ability to kill microorganisms and has no direct contribution to the antifouling effect of the coating. At the same time, due to the relatively short acrylic molecular chain, the formed coating polymer network is not dense and cannot resist the erosion of extreme marine environments. Summary of the Invention

[0005] The present invention aims at the above problems and provides a cationic high-solid-content acrylic resin and a preparation method thereof, and a marine antifouling coating containing the same and a preparation method thereof.

[0006] Aiming at the shortcomings of high-solid acrylic resins in the preparation of marine antifouling coatings, the present invention first synthesizes a cationic high-solid acrylic resin with hydroxyl groups. Cationic groups with antibacterial effects are introduced into the polymer network through the quaternization of dimethylaminoethyl acrylate. Then dendritic polyester polyols are added to increase the density of the polymer three-dimensional network, thereby endowing the coating with excellent mechanical properties and anti-corrosion properties. Finally, aliphatic polyurethane oligomers are used as curing agents, and after curing, a marine antifouling coating with excellent antibacterial properties, low surface energy and weather resistance is obtained. This coating has a significant effect on preventing the adhesion of marine microorganisms and is particularly suitable for protecting the surfaces of offshore platforms, ships and large marine equipment.

[0007] Cations can interact with phospholipid molecules on the negatively charged bacterial cell membrane. The positive charge will damage the integrity of the cell membrane, increase the membrane permeability, cause the cell membrane to rupture or become unstable, resulting in the leakage of intracellular substances, and ultimately lead to the death of bacteria; the hydroxyl groups on the dendritic polyester polyols and the hydroxyl groups provided by hydroxyethyl acrylate react with the isocyanate groups of the aliphatic polyurethane to form a dense three-dimensional network structure, greatly enhancing the anti-corrosion performance and weather resistance of the coating. At the same time, the highly branched structure of the dendritic polyester polyols provides excellent cross-linking ability and stronger coating hardness, thereby improving the abrasion resistance and scratch resistance of the coating. In addition, their branched structure can significantly improve the flexibility and adhesion of the coating, reducing the possibility of cracking during the use of the coating.

[0008] Based on the above research, the technical solutions to be protected by the present invention are as follows:

[0009] In the first aspect of the present invention, a cationic high-solid acrylic resin is provided. This acrylic resin is a high-solid and low-viscosity acrylic resin with a solid content of 70%, a molecular weight of 65,000 - 70,000 (Mw), and a hydroxyl value of 5 - 6 mg KOH / g.

[0010] In terms of composition, this high-solid and low-viscosity acrylic resin, by weight, includes 15 - 20 parts of component A; 12 - 15 parts of component B.

[0011] Among them, component A includes acrylic monomers, antibacterial monomers, initiators, chain transfer agents, solvents, antioxidants, and bromoethane additives.

[0012] Component B includes the solvent propylene glycol dimethyl ether acetate, dendritic polyester polyols, and aliphatic polyurethane curing agents.

[0013] Preferably, in component A, by weight, the acrylic monomers include 100 - 120 parts of methyl methacrylate, 30 - 35 parts of 2-ethylhexyl acrylate, 10 - 12 parts of hydroxyethyl acrylate, and 55 - 60 parts of borneol acrylate.

[0014] The antibacterial monomer is selected from dimethylaminoethyl acrylate. The cation comes from the tertiary amine group of quaternized dimethylaminoethyl acrylate. The cationic amino structure can interact with the anionic components on the bacterial cell membrane, destroying the integrity of the cell membrane, causing cell matrix leakage, thereby inhibiting or killing bacteria. Among them, the amount of dimethylaminoethyl acrylate is 5%-15% of the total amount of acrylic acid monomers.

[0015] Bornyl acrylate is selected from isobornyl acrylate, and can also be replaced by one of the acrylates containing a ring structure such as bornyl methacrylate or cyclohexyl acrylate, so as to increase the molecular weight of the synthetic acrylic resin and reduce the viscosity of the synthetic resin.

[0016] The initiator is AIBN, and the overall proportion is controlled between 0.5% and 1.5% of the acrylic acid monomer; the chain transfer agent is tert-dodecyl mercaptan or n-dodecyl mercaptan, and the addition amount of tert-dodecyl mercaptan is 1% to 2% of the acrylic acid monomer, and the addition amount of n-dodecyl mercaptan is 1.5% to 3% of the acrylic acid monomer.

[0017] The weight proportions of the solvent propylene glycol methyl ether acetate are 60-80 parts, ethyl bromide is 4-6 parts, and the antioxidant is 1-2 parts.

[0018] The antioxidant is selected from the prior art, such as hydroxyphosphonate, hydroxymethylpropylphenyl ether and the like.

[0019] In component B, the polyester polyol is a dendritic polyester polyol H40p, with a hydroxyl value of 500 mg KOH / g, and is dissolved in propylene glycol dimethyl ether acetate. The amount added is low between 0.5% and 2%, medium between 2% and 5%, and high above 5% relative to the total amount of acrylic monomers. When used as an additive to increase the crosslinking degree of coatings, it is generally added in a medium range, that is, between 2% and 5%, to increase the density of the crosslinking system, which can give the coating high durability, wear resistance, adhesion and weather resistance.

[0020] The polyurethane curing agent is an aliphatic polyurethane curing agent HDI, with a viscosity of 2500 mpa·s at 25°C and a -NCO content of 21.8±0.3%. When used with acrylic resin and polyester polyol, the ratio of -NCO to -OH is controlled between 1.2:1-1.4:1. The acrylate-polyester polyol-polyurethane coating formed within this range has excellent stain resistance, UV resistance, mechanical properties and chemical corrosion resistance, and can adapt to complex and harsh marine atmospheric environments.

[0021] More preferably, the cationic high solid content acrylic resin provided by the present invention comprises the following components: in parts by weight: (1) 15-20 parts of component A; and (2) 12-15 parts of component B.

[0022] Component A is in parts by weight and includes: 100 - 120 parts of methyl methacrylate, 30 - 35 parts of 2-ethylhexyl acrylate, 10 - 12 parts of hydroxyethyl acrylate, 55 - 60 parts of isobornyl acrylate, 10 - 12 parts of dimethylaminoethyl acrylate, 60 - 80 parts of propylene glycol monomethyl ether acetate, 1 - 3 parts of AIBN, 3 - 6 parts of tert-dodecyl mercaptan, 4 - 6 parts of ethyl bromide, and 1 - 2 parts of antioxidant.

[0023] Component B is in parts by weight and includes: 12 - 13 parts of propylene glycol dimethyl ether acetate, 0.1 - 0.3 parts of dendritic polyester polyol, and 2 - 4 parts of aliphatic polyurethane curing agent.

[0024] In the second aspect of the present invention, a preparation method of the above-mentioned cationic high-solid-content acrylic resin is provided, which includes the following steps:

[0025] A. Preparation of cationic high-solid-content acrylic solution

[0026] (1) Weigh the solvent propylene glycol monomethyl ether acetate and add it into a container, stir and heat it to 72 ± 1 °C at 300 - 320 r / min, and carry out condensation reflux;

[0027] (2) Weigh the preset proportions of acrylic monomers, antibacterial monomers, initiators, chain transfer agents, and antioxidants, stir them evenly and then drop them into the reaction container at a uniform speed; specifically, weigh the monomers methyl methacrylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, isobornyl acrylate, and dimethylaminoethyl acrylate, mix them evenly and then add the initiator AIBN, the chain transfer agent dodecyl mercaptan, and the antioxidant. Since most substances are liquid, the mixture is also in a liquid state after mixing. Transfer the mixture to a constant-pressure funnel and drop it into the three-necked flask at a speed of 0.3 - 0.4 mL / min at a uniform speed.

[0028] After the dropping is completed, raise the temperature of the system to 75 °C, continue to react overnight, then raise the temperature to 80 °C and react for 2 hours. The polymerization reaction ends, cool down to 60 °C, add ethyl bromide and react for another 2 hours, and then cool down to 40 °C and discharge to obtain the product.

[0029] B. Preparation of cationic high-solid-content acrylic resin

[0030] Dissolve the dendritic polyester polyol in propylene glycol dimethyl ether acetate to obtain a transparent resin solution, and then add it to the acrylic solution, stir for 5 - 10 minutes until it is uniform; weigh the polyurethane curing agent according to the molar ratio of isocyanate group to hydroxyl group of 1.2:1 and add it to the solution. Stir for about 5 - 10 minutes and then stand to remove bubbles to obtain the product.

[0031] In the present invention, acrylic monomers all contain the stabilizer 4-methoxyphenol MEHQ, which is removed by basic alumina before use.

[0032] In the third aspect of the present invention, there is provided the use of the above-mentioned cationic high-solid-content acrylic resin in the preparation of marine antifouling coatings.

[0033] In the fourth aspect of the present invention, there is provided a marine antifouling coating, which comprises a cationic high-solid-content acrylic resin, pigments, fillers and additives. Among them, the cationic high-solid-content acrylic resin is as described in any one of the above.

[0034] The pigments and fillers are selected from one of silica, iron(III) oxide, silica, zinc oxide, clay, barium sulfate, mica powder; the additives are one or several of a leveling agent, a defoaming agent, and a dispersant.

[0035] Specifically, the leveling agent is one of BYK-S3700, BYK-354, DH-3187, FLOW-100; the defoaming agent is one of CL-266, KS-66, KSZ-108; the dispersant is one of S-100 polyether polymer dispersant, EFKA-4401, 6161A. During actual operation, selection can be made according to actual requirements.

[0036] In the fifth aspect of the present invention, there is provided a method for preparing the above-mentioned marine antifouling coating, which comprises the following steps:

[0037] Add the obtained cationic high-solid-content acrylic resin into a dispersion device, add additives, and disperse at a rotation speed of 100 - 200 rpm for about 30 minutes; then add pigments and fillers, and disperse at 500 - 800 rpm for about 30 minutes to obtain the antifouling coating.

[0038] Coat the antifouling coating on the surface of the substrate, and prepare an antifouling coating with a film thickness of 100 - 200 μm through crosslinking and curing. When operating in the laboratory, in order to save time, after brushing, the substrate is left standing for 2 hours until part of the coating solvent evaporates, then transferred to an oven, the oven temperature is set at 100°C, and the heating and curing time is 2 hours. After the curing reaction ends, the substrate is left standing at room temperature for 2 hours until it is completely cooled, and then the next performance test is carried out.

[0039] Compared with the existing methods, the present invention has the following advantages:

[0040] The present invention obtains a cationic high-solid-content acrylic resin as the main part of the marine antifouling coating through free radical polymerization. The ultra-high solid content of more than 70% means ultra-low VOC emissions, which is more environmentally friendly and meets the national energy conservation and carbon reduction strategic requirements and the concept of marine protection.

[0041] Due to the relatively short molecular chains of high-solid and low-viscosity resins, it is difficult to form a stable cross-linked dense network structure. The performance of the coatings obtained by using them alone is average. In the present invention, branched polyester polyol is introduced to increase the cross-linking density, and aliphatic polyurethane is used as the curing agent. The branched polyester polyol provides multiple binding sites between the isocyanate groups and the acrylic molecular chains, which can form a three-dimensional cross-linked network. The coatings formed have excellent mechanical properties, better flexibility, better adhesion, and are more tightly bonded to the substrate. The combined use of aliphatic polyurethane and polyester polyol can improve the ultraviolet resistance, temperature and humidity resistance of the coatings, making the coatings more suitable for marine environments.

[0042] The advantage of cationic antibacterial components is their broad-spectrum antibacterial property, which can be effective against a variety of bacteria, fungi, and algae, and has a broad antibacterial effect; they also have low toxicity. Compared with some traditional antibacterial agents, these compounds usually have lower toxicity and are more friendly to humans and the environment. More importantly, when cations are the main components for sterilization, they are not easily resistant to drugs and can effectively prevent the attachment of marine microorganisms for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Shows the comparison of the antibacterial and antifouling test results between the blank control group and Example 1;

[0044] Figure 2 Shows the comparison of the experimental results of algae attachment between the blank control group and Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0045] The following examples and experimental examples further illustrate the present invention and should not be construed as limiting the present invention. The examples do not include a detailed description of traditional methods, such methods are well known to those of ordinary skill in the art and are described in many publications.

[0046] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to the described content can be applied to the present invention. The preferred implementation methods and materials described in the detailed description are for illustrative purposes only.

[0047] The present invention uses a hydroxyl-containing cationic acrylic resin as the main body. The hydroxyl groups on the molecular chain of the acrylic resin and the dendritic polyester polyol react with isocyanate groups together to finally form an antibacterial and antifouling coating with low surface energy and excellent weather resistance. Specifically, in the main body part, by adjusting the ratios of methyl methacrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, dimethylaminoethyl acrylate, initiator AIBN, and chain transfer agent tert-dodecyl mercaptan, a cationic acrylic resin with high solid content is obtained. The quaternization of dimethylaminoethyl acrylate introduces cations with antibacterial effects into the polymer network. The dendritic polyester polyol is used as an additive to increase the density of the cross-linking system and enhance the mechanical properties, and the aliphatic polyurethane is used as a curing agent to improve the antifouling property, corrosion resistance, and weather resistance of the coating film. Finally, an ocean antifouling coating with excellent comprehensive properties is obtained after blending with pigments and fillers.

[0048] I. Preparation of Cationic Acrylic Resin Coating with High Solid Content

[0049] Example 1

[0050] A. Preparation of Cationic Acrylic Resin Solution with High Solid Content

[0051] Weigh 26.2 g of propylene glycol dimethyl ether acetate and add it to a three-necked flask. Turn on the condensation reflux device. After cooling, raise the temperature of the oil bath to 72 °C, and at this time, control the stirring speed at 300 r / min. Weigh 35 g of methacrylate, 10.4 g of 2-ethylhexyl acrylate, 17.6 g of isobornyl acrylate, 3.5 g of 2-hydroxyethyl acrylate, and 3.5 g of dimethylaminoethyl acrylate and add them to a beaker, and stir for 3 minutes on a magnetic stirrer to mix evenly. Weigh 0.56 g of AIBN, 1.05 g of tert-dodecyl mercaptan, and 0.35 g of antioxidant and add them to the beaker. Pour all the monomers, initiator, and chain transfer agent into a constant pressure funnel and slowly drip them into the reaction kettle at a speed of 0.3 - 0.4 ml / min. After the dripping is completed, raise the temperature of the oil bath to 75 °C overnight, add 0.05 g of AIBN dissolved in 1 g of propylene glycol dimethyl ether acetate, raise the temperature to 80 °C and react for 2 hours, cool down to 60 °C, add 3.2 g of bromoethane and react for another 2 hours, and then cool down to 40 °C to discharge the material. The reaction ends to obtain a cationic acrylic resin solution with high solid content.

[0052] B. Preparation of Cured Coating of Cationic Acrylic Resin with High Solid Content

[0053] Take 0.07 g of dendritic polyester polyol and dissolve it in 3.75 g of propylene glycol dimethyl ether acetate, heat it to 50 °C, and stir it for 10 minutes until it is completely dissolved to obtain a transparent resin solution. Pour the solution into the acrylic acid solution in step A and stir it for another 5 minutes to disperse it evenly. Weigh the polyurethane curing agent according to 1.2-1.4 times the molar mass of the hydroxyl group, that is, 0.875 g N3300, add it to the system, and stir it at room temperature for 5-10 minutes until it is completely mixed.

[0054] Take 0.5 g of the solution and brush it evenly on the pretreated tinplate or glass slide. Let it stand for 2 hours until the coating solvent evaporates. When the coating solution cannot flow obviously, transfer it to the oven. Set the oven temperature to 100 °C and heat curing time for 1-2 hours.

[0055] Example 2

[0056] The only difference from Example 1 is that the content of the cationic monomer dimethylaminoethyl acrylate is 10% of the acrylic acid monomer, and the specific mass is 7 g.

[0057] The specific processes of Examples 1 and 2 are the same, but the ratios of additives and cationic monomers are different. The specific details are shown in Table 1 below:

[0058] Table 1 Summary of formulation compositions of Examples 1 to 2

[0059]

[0060] 2. Technical Effect Verification

[0061] The cationic high-solid acrylic coating prepared in the above embodiment was tested by using a cross-hatch tape peeling adhesion test, a surface energy test, an antibacterial test, and an algae adhesion test.

[0062] Test 1: Adhesion test---frame tape peeling test

[0063] A 25 mm×75 mm×1 mm glass slide was pretreated, cleaned and dried, and then coated with the cationic high solid content acrylic resin coating synthesized in Examples 1-2, baked at 100° C. for 1 hour, and then allowed to stand in a dry environment for 2 hours for use.

[0064] Use a grid drawer to draw a pattern with a spacing of 1mm×1mm on the coating, quickly stick the tape on the scratch, press until it is fully in contact, then tear off the tape, observe the coating damage, and grade the coating adhesion. The standards are as follows:

[0065] Level 0B: It represents that the peeling area of the paint is greater than 65%; Level 1B: The peeling area is greater than 35% and less than 65%; Level 2B: The peeling area exceeds 15% and does not exceed 35%; Level 3B: The peeling area is greater than 5% and less than 15%; Level 4B: The actual damage in the scribed area is less than or equal to 5%; Level 5B: There is no peeling at the grid edge, and the cut edge is completely smooth, which is the highest level of adhesion.

[0066] Test 2: Surface free energy test

[0067] Use a Dataphysics OCA20 contact angle measuring instrument to measure the contact angles of deionized water and diiodomethane on the coating, and calculate the surface energy of the coating according to the WORK model.

[0068]

[0069] There are two unknown terms in the equation and , and two liquids with known dispersion and polar components are needed to solve this problem. Two liquids with the main polar and main dispersion parts should be selected during the test.

[0070] Test 3: Antibacterial and antifouling test

[0071] The antifouling performance test of the coating refers to the national standard GB / T 21866-2008 "Determination Method and Antibacterial Effect of Antibacterial Coatings (Paint Films)". Prepare the coating film according to the requirements of GB / T1727. The coating is generally applied in two coats. The second coat is applied after the first coat is surface dry. The total thickness of the wet coating film is less than 100 μm. The sample plate should be flat, rust-free, and free of oil stains, etc. After the plate is coated, it is dried for 7 days according to the provisions of GB / T9278 before use. The size of the plate is a 50×50 mm test plate, and it is sterilized by ultraviolet light in a clean bench for 5 minutes before use.

[0072] Result calculation:

[0073] The formula for calculating the antibacterial rate is: R = (B - C / B) × 100%

[0074] In the formula:

[0075] R - The antibacterial rate, expressed in (%), and the value is taken to four significant figures, carried out according to the provisions in GB / T1250;

[0076] B - The average number of recovered bacteria (CFU / piece) of the blank control sample plate after 24 hours;

[0077] C - The average number of recovered bacteria (CFU / piece) of the antibacterial coating sample plate after 24 hours.

[0078] The above three test results are summarized in Table 2 below:

[0079] Table 2 Test Results of Cationic High-Solids Acrylic Coatings in Examples 1 - 2

[0080]

[0081] The results show that the cured acrylic coating has an adhesion of the highest grade 5B, indicating that the resin obtained in the examples can adhere well to the substrate without falling off, and the adhesion is excellent. From the surface energy test results, it can be seen that the surface energy of the cured acrylic coating is relatively low, so it can exhibit effective anti-fouling performance.

[0082] Figure 1 The picture showing the inhibition results of the anti-fouling coating against Pseudomonas aeruginosa is presented. From left to right in the picture are the blank control group and Example 1. The results show that the coating with cations as the antibacterial component can play an excellent inhibitory role against Pseudomonas aeruginosa, indicating the antibacterial effectiveness of the marine anti-fouling acrylic coating.

[0083] Test 4: Algae Adhesion Experiment

[0084] A mixed algal species composed of green algae, Chlorella and diatoms was selected and dispersed in an aqueous solution (algal concentration 20 - 100 μg / mL), and cultured at room temperature and relative humidity of 55% - 65%. The specimens coated with the resin of Example 1 and the blank control specimens were immersed in the algal solution, and the surface algae attachment was regularly photographed and recorded. The results are as follows: When the initial algal concentration was 20 μg / mL, no obvious algae attachment was observed on the surface of the resin specimen after 168 h, while discrete algal patches had formed on the surface of the blank sample. When the algal solution concentration was increased to 60 μg / mL and soaked for 504 h, the surface of the resin remained basically clean, while the blank substrate was covered by a dense algal layer and accompanied by the expansion of rust spots. When the algal concentration was further increased to 100 μg / mL and the soaking time was extended to 576 h, only sporadic algal patches appeared on the surface of the resin, while the blank substrate was completely covered by the biofilm formed by algae organisms ( Figure 2 )

[0085] The parts not described in this invention are the same as the prior art or are implemented using the prior art. The applicant declares that the detailed method of this invention is illustrated by the above examples, but this invention is not limited to the above detailed method, that is, it does not mean that this invention must rely on the above detailed method to be implemented. Those skilled in the art should understand that any improvement to this invention, the equivalent substitution of the raw materials of the products of this invention and the addition of auxiliary components, the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of this invention.

Claims

1. A cationic high-solid-content acrylic resin, characterized in that, By weight parts, it includes 15 - 20 parts of component A; 12 - 15 parts of component B; Component A includes acrylic monomers, antibacterial monomers, initiators, chain transfer agents, solvents, antioxidants, and bromoethane additives; By weight parts, the acrylic monomers include 100 - 120 parts of methyl methacrylate, 30 - 35 parts of 2 - ethylhexyl acrylate, 10 - 12 parts of hydroxyethyl acrylate, and 55 - 60 parts of isobornyl acrylate; The antibacterial monomer is selected from dimethylaminoethyl acrylate, and the dosage is 5% - 15% of the total amount of acrylic monomers; The initiator is AIBN, and the overall proportion is controlled between 0.5% - 1.5% of the acrylic monomers; The chain transfer agent is tert - dodecyl mercaptan or n - dodecyl mercaptan. The addition amount of tert - dodecyl mercaptan is 1% - 2% of the acrylic monomers, and the addition amount of n - dodecyl mercaptan is 1.5% - 3% of the acrylic monomers; The solvent is selected from propylene glycol monomethyl ether acetate, with a weight part of 60 - 80 parts; the weight part of bromoethane is 4 - 6 parts, and the weight part of the antioxidant is 1 - 2 parts, Component B includes the solvent propylene glycol dimethyl ether acetate, dendritic polyester polyol, and aliphatic polyurethane curing agent, The dendritic polyester polyol is selected from H40p, with a hydroxyl value of 500 mg KOH / g. The addition amount, counted relative to the total amount of acrylic monomers, is between 0.5% - 5%; when used, it is made into a solution with propylene glycol dimethyl ether acetate; The aliphatic polyurethane curing agent is selected from HDI, with a viscosity of 2500 mpa·s at 25℃ and an - NCO content of 21.8 ± 0.3%. When used in combination with component A and polyester polyol, the ratio of - NCO to - OH is controlled between 1.2:1 - 1.4:

1.

2. The cationic high-solid acrylic resin according to claim 1, wherein In component A, the isobornyl acrylate is selected from any one of isobornyl acrylate, bornyl methacrylate, and cyclohexyl acrylate.

3. The cationic high-solid acrylic resin according to claim 2, wherein The acrylic resin is a high - solid and low - viscosity acrylic resin, with a solid content of 70%, a molecular weight of 65000 - 70000 Mw, and a hydroxyl value of 5 - 6 mg KOH / g acrylic resin.

4. A method for preparing the cationic high-solid acrylic resin according to any one of claims 1 to 3, characterized in that, It includes the following steps: A. Preparation of cationic high - solid - content acrylic solution (1) Weigh the solvent propylene glycol monomethyl ether acetate and add it to a container, stir and heat up to 72 ± 1 ℃, and carry out condensation reflux; (2) Weigh the preset proportions of acrylic monomers, antibacterial monomers, initiators, chain transfer agents, and antioxidants, stir evenly and then slowly add them dropwise to the reaction container; after the dropping is completed, raise the temperature of the system to 75 ℃, continue the reaction overnight, then raise the temperature to 80 ℃ and react for 2 hours. The polymerization reaction ends, cool down to 60 ℃, add bromoethane and react for another 2 hours, and then cool down to 40 ℃ to discharge to obtain it, B. Preparation of cationic high - solid - content acrylic resin Dissolve the dendritic polyester polyol in propylene glycol dimethyl ether acetate to obtain a transparent resin solution, and then add it to the acrylic solution, stir for 5 - 10 minutes until uniform; weigh the polyurethane curing agent according to the molar ratio of isocyanate group to hydroxyl group of 1.2:1 and add it to the solution, stir for 5 - 10 minutes, and let it stand to remove bubbles to obtain it.

5. The preparation method of the cationic high solid content acrylic resin according to claim 4, characterized in that, In the preparation step of the cationic high-solid-content acrylic acid solution in step A, in step (1), the rotation speed of the stirring paddle is controlled at 300 - 320 r / min; in step (2), it is uniformly added dropwise at a speed of 0.3 - 0.4 mL / min.

6. Use of the cationic high-solid-content acrylic resin according to any one of claims 1 to 3 in the preparation of a marine antifouling coating.

7. An anti-fouling marine coating, characterized in that, It includes a cationic high-solid-content acrylic resin, a pigment extender, and an additive. The cationic high-solid-content acrylic resin is as described in any one of claims 1 to 3. The pigment extender is selected from one of silica, iron(III) oxide, zinc oxide, clay, barium sulfate, and mica powder. The additive is one or several of a leveling agent, an antifoaming agent, and a dispersant.

8. The marine antifouling coating according to claim 7, wherein The antifouling coating is applied to the surface of the substrate, and an antifouling coating with a film thickness of 100 - 200 μm is prepared through crosslinking and curing.

9. The preparation method of the marine antifouling paint according to claim 7, characterized in that, It includes the following steps: adding the cationic high-solid-content acrylic resin into a dispersion device, adding an additive, dispersing for 30 minutes at a rotation speed controlled at 100 - 200 rpm; then adding the pigment extender and dispersing for 30 minutes at 500 - 800 rpm as well to obtain the marine antifouling coating.

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