Environment-friendly antifouling coating based on synergistic effect of natural products

Abstract

The application discloses an environment-friendly antifouling paint based on synergistic effect of natural products, belongs to the technical field of paints and is suitable for biological fouling protection of ships, ocean platforms and offshore wind power towers. The paint is composed of natural product antifouling agent 5-20 parts, environment-friendly film forming agent 30-50 parts, dispersing agent 2-5 parts, thickening agent 1-3 parts, defoaming agent 0.5-2 parts and environment-friendly solvent 20-40 parts in parts; the natural product antifouling agent is formed by compounding marine plant extract and plant essential oil at a ratio of 1:1-3:1, and a synergistic mechanism of 'inhibition-kill-repell' is formed. The application has the advantages of simple preparation process, no special equipment, no heavy metal and organic tin in the paint, biological degradation rate greater than or equal to 80%, high antifouling efficiency, long effective period, strong coating adhesion and the like, solves the defects of poor environmental protection and poor synergy of the existing antifouling paint, is suitable for long-term service requirements in three fields and has high practical value and industrialization popularization prospect.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically relating to an environmentally friendly antifouling coating, which is particularly suitable for antifouling treatment of the surfaces of facilities prone to biofouling, such as ships, offshore platforms, and offshore wind turbine towers. It can effectively inhibit or repel various fouling organisms such as bacteria, fungi, barnacles, and mussels, and has both environmental friendliness and long-lasting antifouling performance. Background Technology

[0002] Biofouling is a major common challenge faced by ships, offshore platforms, and offshore wind turbine towers. It refers to the process by which microorganisms such as bacteria, fungi, barnacles, and mussels, as well as plants and animals, attach to, grow, and reproduce on the surface of facilities. It can seriously affect the normal operation of these three sectors: ships experience increased navigation resistance, higher fuel consumption, and accelerated hull corrosion; offshore platforms and other facilities suffer from intensified structural corrosion, shortened service life, and increased maintenance difficulty; and offshore wind turbine towers have denser underwater and near-water surface fouling, which increases structural weight and fluid resistance, accelerates steel corrosion, interferes with equipment maintenance and power generation stability, and increases maintenance costs and safety risks.

[0003] Currently, antifouling coatings are the most widespread and economical antifouling method in the three major marine sectors. However, existing antifouling technologies still have many shortcomings and are difficult to meet actual needs: Traditional antifouling coatings rely on heavy metal active ingredients such as organotin and cuprous oxide, which have problems such as strong leaching toxicity and bioaccumulation, and have been strictly restricted by relevant international conventions and regulations; existing natural product antifouling coatings mostly use single natural ingredients, with a narrow antifouling spectrum, limited effect, and short duration of action (mostly less than 6 months), making it difficult to adapt to the long-term service requirements of the three major sectors, and some compound products have not formed a clear synergistic mechanism, and even have the risk of anti-synergistic effects; some natural product antifouling coatings add toxic and harmful synthetic additives, which do not meet environmental protection standards and are contrary to the green development trend of the sector; at the same time, natural product antifouling agents have poor dispersibility and poor overall coating performance, making it difficult to adapt to complex and harsh marine environments, and some new environmentally friendly coatings have complex preparation processes and high costs, which are not conducive to industrial promotion.

[0004] Developing an antifouling coating that is based on the synergistic effect of natural products, has both high antifouling efficiency and environmental friendliness, and is suitable for use in three major fields has become a pressing technical challenge in this field. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an environmentally friendly antifouling coating based on the synergistic effect of natural products. The core objectives are fourfold: first, to construct a synergistic antifouling system using natural products, achieving efficient and long-lasting antifouling and addressing the limitations of single-component antifouling; second, to use environmentally friendly components throughout the system, free from heavy metals, organotin, and other harmful substances, aligning with green development requirements; third, to optimize coating dispersibility and overall coating performance, adapting to complex marine environments; and fourth, to provide a simple and easily industrialized preparation process, reducing production and application costs.

[0006] To achieve the above-mentioned objectives, this invention provides an antifouling coating, which adopts the following technical solution: 5-20 parts of natural product antifouling agent, 30-50 parts of environmentally friendly film-forming agent, 2-5 parts of dispersant, 1-3 parts of thickener, 0.5-2 parts of defoamer, and 20-40 parts of environmentally friendly solvent; In the aforementioned environmentally friendly antifouling coating, the selected natural product antifouling agent is a compound of marine plant extracts and plant essential oils. The marine plant extracts are selected from at least one of seaweed polysaccharides, kelp extracts, and laver extracts, and the plant essential oils are selected from at least one of peppermint essential oil, cinnamon essential oil, and tea tree essential oil. The mass ratio of marine plant extracts to plant essential oils is 1:1 to 3:1.

[0007] The environmentally friendly film-forming agent is selected from at least one of waterborne polyurethane film-forming agents and waterborne acrylic film-forming agents.

[0008] The dispersant is selected from at least one of sodium polycarboxylate and sodium lignosulfonate.

[0009] The thickener is selected from at least one of xanthan gum and sodium carboxymethyl cellulose.

[0010] The defoamer is an environmentally friendly silicone-based defoamer.

[0011] The environmentally friendly solvent is selected from at least one of deionized water and ethanol.

[0012] The present invention also provides a method for preparing the antifouling coating described in the above technical solution, comprising the following steps: S1. Accurate Material Weighing: Weigh the environmentally friendly solvent, dispersant, thickener, natural product antifouling agent, environmentally friendly film-forming agent, and defoamer according to their mass percentages. All raw materials are pre-treated to remove impurities, ensuring their purity. This coating consists of 5-20 parts of natural product antifouling agent, 30-50 parts of environmentally friendly film-forming agent, 2-5 parts of dispersant, 1-3 parts of thickener, 0.5-2 parts of defoamer, and 20-40 parts of environmentally friendly solvent by weight percentage.

[0013] S2. Additive premixing: Weigh out the environmentally friendly solvent, dispersant and thickener and add them to the stirring device in sequence. Stir at 500-800 r / min for 10-20 minutes at room temperature (20-25℃) until all components are completely dissolved to obtain a uniform and lumpy transparent mixture.

[0014] S3. Antifouling agent dispersion: Add the pre-prepared natural product antifouling agent to the above mixture, adjust the stirring speed to 1000-1500r / min, and disperse at high speed for 20-30 minutes. Keep the temperature at room temperature during the dispersion process. After completion, perform a preliminary visual inspection to ensure that the antifouling agent does not agglomerate or separate.

[0015] S4. Mixing film-forming agent and defoamer: Add the weighed environmentally friendly film-forming agent and defoamer to the antifouling agent dispersion, adjust the speed to 800-1000 r / min, and continue stirring for 10-15 minutes to fully integrate the coating components and form a uniform coating base.

[0016] S5. Grinding and particle size detection: The above coating base material is fed into a sand mill for grinding. After grinding, a laser particle size analyzer is used to detect the particle size to ensure that the particle size of the system is ≤50μm. If the particle size does not meet the standard, grinding is continued until it meets the requirements to ensure the smoothness of the coating in subsequent construction.

[0017] S6. Sealed Curing: The qualified coating base material is sent into a sealed curing tank and cured at room temperature (20-25℃) for 2-4 hours to naturally eliminate residual air bubbles generated during the stirring and grinding process in the system and stabilize the performance of the coating system.

[0018] S7. Initial Inspection and Adjustment of Finished Product: After curing, the appearance and viscosity of the coating are initially inspected. If the viscosity does not meet the construction requirements, a small amount of environmentally friendly solvent can be added for fine adjustment. Finally, an environmentally friendly antifouling coating based on the synergistic effect of natural products is obtained.

[0019] The above preparation method only breaks down and adds simple steps such as material weighing and initial inspection and adjustment of finished products on the basis of the original method. There are no additional process difficulties or equipment requirements. The entire process is carried out at room temperature with low energy consumption. Moreover, the quality control requirements of each step can effectively improve the consistency of the finished product. No toxic or harmful substances are generated during the preparation process, which meets the requirements of environmentally friendly production and is easy to promote on a large scale in industrial applications.

[0020] The core of the antifouling coating of this invention lies in the synergistic compounding of natural product antifouling agents and the optimized combination of environmentally friendly components throughout the system. All components of this coating are free of heavy metals, organotin compounds, and recalcitrant synthetic toxins, and have a biodegradability rate of ≥80%. Each component performs its specific function while working synergistically to achieve highly efficient antifouling, environmental friendliness, and excellent coating performance. The specific functions and synergistic mechanisms of each component are as follows: 1. Natural Product Antifouling Agent: This is the core antifouling active component of the coating, formulated by blending marine plant extracts and plant essential oils in a mass ratio of 1:1 to 3:1. The marine plant extracts are selected from at least one of seaweed polysaccharides, kelp extracts, and laver extracts. The active ingredient is a polysaccharide that can bind to receptors on the surface of fouling organisms, interfering with their attachment signal transduction and inhibiting the attachment and metamorphosis of fouling organisms at the source. The plant essential oils are selected from at least one of peppermint oil, cinnamon oil, and tea tree oil. The active ingredients are terpenoids and phenolic substances that can directly destroy the cell membrane structure of fouling organisms, effectively killing fouling organisms and having a significant repellent effect. The combination of the two forms a synergistic mechanism of "inhibition-killing-repellent," broadening the antifouling spectrum and simultaneously resisting various fouling organisms such as bacteria, fungi, barnacles, and mussels. It also reduces the dosage of single components, reduces environmental impact, significantly improves antifouling efficiency and duration of effectiveness, and avoids the anti-synergistic risks of existing compound products.

[0021] 2. Environmentally friendly film-forming agent: This is the core component for substrate bonding and film formation in coatings. It is selected from at least one of waterborne polyurethane film-forming agents and waterborne acrylic film-forming agents, and can be used alone or in combination. Waterborne polyurethane film-forming agents give the coating strong adhesion and excellent resistance to seawater erosion, while waterborne acrylic film-forming agents improve the coating's weather resistance and reduce raw material costs. The two work together to form a dense and stable coating film that can firmly fix the antifouling agent and protect the substrate from seawater corrosion. At the same time, it has good compatibility with other environmentally friendly components and no harmful substances are released.

[0022] 3. Dispersant: Selected from at least one of sodium polycarboxylate and sodium lignosulfonate, it is an environmentally friendly anionic dispersant that can effectively improve the dispersibility of natural product antifouling agents in the coating system, prevent their aggregation and sedimentation, ensure that the antifouling components are evenly distributed in the coating, guarantee the stability of the antifouling effect of the coating, and improve the surface smoothness after coating application.

[0023] 4. Thickener: Selected from at least one of xanthan gum and sodium carboxymethyl cellulose, it is a natural / semi-synthetic environmentally friendly thickener that can precisely adjust the viscosity of the coating, prevent the coating from separating or settling during storage and application, improve the application performance of the coating by brushing, rolling, and spraying, ensure the uniformity of the coating thickness, and avoid local antifouling failure caused by uneven coating thickness.

[0024] 5. Defoamer: Selected from silicone-based environmentally friendly defoamers (such as polydimethylsiloxane), which can quickly eliminate bubbles generated by stirring and grinding in each stage of coating preparation, avoid defects such as pinholes, pits, and shrinkage cavities on the surface after coating application, improve the density of the coating, and enhance the coating's resistance to seawater immersion and antifouling duration.

[0025] 6. Environmentally friendly solvent: Selected from at least one of deionized water and ethanol, with preference given to composite solvents of deionized water and ethanol in a ratio of 1:1 to 2:1. It contains no volatile toxic substances, is easily volatile and leaves no residue. It can effectively dissolve and disperse the components, improve the compatibility of the system, and adjust the viscosity of the coating during application. Moreover, there are no harmful residues after the solvent evaporates, which meets environmental protection requirements. At the same time, the raw material cost is low, which is conducive to industrial promotion.

[0026] This invention achieves an organic combination of high efficiency and long-lasting antifouling, environmental friendliness throughout the process, excellent coating performance, and simple preparation process through precise proportioning of various environmentally friendly components, synergistic design of natural product antifouling agents, and refined optimization of the preparation process. It perfectly meets the antifouling needs of three major fields: ships, offshore platforms, and offshore wind turbine towers. It effectively solves the technical defects of existing antifouling coatings, such as insufficient environmental protection, poor synergy, short effective period, and poor coating performance. It has extremely high practical value and prospects for industrial promotion. Detailed Implementation

[0027] To further illustrate the technical solution and implementation effects of the present invention, the present invention will be described in detail below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. All modifications and equivalent substitutions made based on the technical solution of the present invention shall fall within the protection scope of the present invention.

[0028] In the following examples, all raw materials used were commercially available conventional products: seaweed polysaccharide (purity ≥90%), kelp extract (purity ≥85%), peppermint oil (food grade, purity ≥99%), cinnamon oil (food grade, purity ≥99%), waterborne polyurethane film-forming agent (solid content 40%), waterborne acrylic film-forming agent (solid content 45%), sodium polycarboxylate (industrial grade), xanthan gum (food grade), silicone defoamer (industrial grade, polydimethylsiloxane content ≥98%), ethanol (industrial grade, purity ≥95%), and deionized water (self-made).

[0029] Example 1 An environmentally friendly antifouling coating based on the synergistic effect of natural products comprises the following components by mass percentage: 4% seaweed polysaccharide, 6% peppermint oil (total mass of natural product antifouling agents 10%, mass ratio of the two is 2:1), 40% waterborne polyurethane film-forming agent, 3% sodium polycarboxylate, 2% xanthan gum, 1% silicone defoamer, 24% deionized water, and 20% ethanol (total solvent mass 44%, mixing ratio 1.2:1). The preparation method is as follows: S1. Accurate weighing of materials: Weigh out 24% deionized water, 20% ethanol, 3% sodium polycarboxylate, 2% xanthan gum, 4% seaweed polysaccharide, 6% peppermint oil, 40% water-based polyurethane film-forming agent, and 1% organosilicon defoamer according to the above mass percentages. All raw materials are pretreated to remove impurities to ensure the purity of the raw materials.

[0030] S2. Additive premixing: Add 24% deionized water, 20% ethanol, 3% sodium polycarboxylate, and 2% xanthan gum to the stirring device in sequence. Stir at 600 r / min for 15 minutes at room temperature (25°C) until all components are completely dissolved to obtain a uniform, lumpy, transparent mixture.

[0031] S3. Antifouling agent dispersion: Add 4% seaweed polysaccharide and 6% peppermint essential oil to the above mixture, adjust the stirring speed to 1200r / min, and disperse at high speed for 25 minutes. Keep the temperature at room temperature during the dispersion process. After completion, perform a preliminary visual inspection to ensure that the antifouling agent does not agglomerate or separate.

[0032] S4. Mixing film-forming agent and defoamer: Add 40% water-based polyurethane film-forming agent and 1% silicone defoamer to the antifouling agent dispersion, adjust the speed to 900 r / min, and continue stirring for 12 minutes to fully integrate the coating components and form a uniform coating base.

[0033] S5. Grinding and particle size detection: The above coating base material is fed into a sand mill for grinding. After grinding, a laser particle size analyzer is used to detect the particle size of the system to ensure that the particle size is ≤50μm.

[0034] S6. Sealed Curing: The qualified grinding coating base is sent into a sealed curing tank and cured at room temperature (25°C) for 3 hours to naturally eliminate residual air bubbles in the system and stabilize the performance of the coating system.

[0035] S7. Initial Inspection and Adjustment of Finished Product: After curing, the coating is initially inspected for appearance and viscosity. The coating has a uniform appearance without any abnormalities and the viscosity meets the construction requirements. No fine-tuning is required, and the final antifouling coating is obtained.

[0036] Performance testing: The coating has a uniform appearance, no bubbles, and no sediment; the coating adhesion (cross-cut test) is grade 1; the seawater erosion resistance (immersion for 30 days) shows no peeling or discoloration; the barnacle adhesion inhibition rate is ≥92%, and the antibacterial rate against bacteria (Escherichia coli, Staphylococcus aureus) is ≥95%; the antifouling effect lasts for ≥12 months; the biodegradability rate is ≥85%; heavy metals (lead, cadmium, mercury, copper) were not detected, meeting environmental protection requirements.

[0037] Example 2 An environmentally friendly antifouling coating based on the synergistic effect of natural products comprises the following components by mass percentage: 3% kelp extract, 5% cinnamon essential oil (8% of total natural product antifouling agent by mass, with a mass ratio of 1:1.7), 45% water-based acrylic film-forming agent, 2% sodium lignosulfonate, 1% sodium carboxymethyl cellulose, 0.5% silicone defoamer, 30% deionized water, and 8.5% ethanol (38.5% of total solvent by mass, with a mixing ratio of 3.5:1). The preparation method is as follows: S1. Accurate weighing of materials: Weigh out 30% deionized water, 8.5% ethanol, 2% sodium lignosulfonate, 1% sodium carboxymethyl cellulose, 3% kelp extract, 5% cinnamon essential oil, 45% water-based acrylic film-forming agent, and 0.5% organosilicon defoamer according to the above mass percentages. All raw materials are pretreated to remove impurities to ensure the purity of the raw materials.

[0038] S2. Premixing of additives: Add 30% deionized water, 8.5% ethanol, 2% sodium lignosulfonate, and 1% sodium carboxymethyl cellulose to a stirring device in sequence. Stir at 500 r / min for 20 minutes at room temperature (22℃) until all components are completely dissolved to obtain a homogeneous, lumpy, transparent mixture.

[0039] S3. Antifouling agent dispersion: Add 3% kelp extract and 5% cinnamon essential oil to the above mixture, adjust the stirring speed to 1000r / min, and disperse at high speed for 30 minutes. Keep the temperature at room temperature during the dispersion process. After completion, perform a preliminary visual inspection to ensure that the antifouling agent does not agglomerate or separate.

[0040] S4. Mixing film-forming agent and defoamer: Add 45% water-based acrylic film-forming agent and 0.5% silicone defoamer to the antifouling agent dispersion, adjust the speed to 800 r / min, and continue stirring for 15 minutes to fully integrate the coating components and form a uniform coating base.

[0041] S5. Grinding and particle size detection: The above coating base material is fed into a sand mill for grinding. After grinding, a laser particle size analyzer is used to detect the particle size of the system to ensure that the particle size is ≤50μm.

[0042] S6. Sealed Curing: The qualified coating base material is sent into a sealed curing tank and cured at room temperature (22℃) for 4 hours to naturally eliminate residual air bubbles in the system and stabilize the performance of the coating system.

[0043] S7. Initial Inspection and Adjustment of Finished Product: After curing, the coating is initially inspected for appearance and viscosity. The coating has a uniform appearance without any abnormalities and the viscosity meets the construction requirements. No fine-tuning is required, and the final antifouling coating is obtained.

[0044] Performance testing: The coating has a uniform appearance, no bubbles, and no sediment; the coating adhesion (cross-cut test) is grade 1; the seawater erosion resistance (immersion for 30 days) shows no peeling or discoloration; the barnacle adhesion inhibition rate is ≥90%, and the bacterial inhibition rate is ≥94%; the antifouling effect lasts for ≥11 months; the biodegradability rate is ≥82%; no heavy metals were detected, meeting environmental protection requirements.

[0045] Example 3 An environmentally friendly antifouling coating based on the synergistic effect of natural products comprises the following components by mass percentage: 6% seaweed polysaccharide, 6% laver extract, 3% cinnamon essential oil (total mass of natural product antifouling agents 15%, marine plant extract to plant essential oil mass ratio 4:1), 20% waterborne polyurethane film-forming agent, 15% waterborne acrylic film-forming agent (total mass of film-forming agents 35%, mixing ratio 1.3:1), 5% sodium polycarboxylate, 3% xanthan gum, 2% silicone defoamer, 20% deionized water, and 20% ethanol (total mass of solvents 40%, mixing ratio 1:1). The preparation method is as follows: S1. Accurate weighing of materials: Weigh 20% deionized water, 20% ethanol, 5% sodium polycarboxylate, 3% xanthan gum, 6% seaweed polysaccharide, 6% laver extract, 3% cinnamon essential oil, 20% water-based polyurethane film-forming agent, 15% water-based acrylic film-forming agent, and 2% silicone defoamer according to the above mass percentages. All raw materials are pretreated to remove impurities to ensure the purity of the raw materials.

[0046] S2. Additive premixing: Add 20% deionized water, 20% ethanol, 5% sodium polycarboxylate, and 3% xanthan gum to the stirring device in sequence. Stir at 800 r / min for 10 minutes at room temperature (20°C) until all components are completely dissolved to obtain a homogeneous, lump-free, transparent mixture.

[0047] S3. Antifouling agent dispersion: Add 6% seaweed polysaccharide, 6% laver extract, and 3% cinnamon essential oil to the above mixture, adjust the stirring speed to 1500 r / min, and disperse at high speed for 20 minutes. Keep the temperature at room temperature during the dispersion process. After completion, perform a preliminary visual inspection to ensure that the antifouling agent does not agglomerate or separate.

[0048] S4. Mixing film-forming agent and defoamer: Add 20% waterborne polyurethane film-forming agent, 15% waterborne acrylic film-forming agent, and 2% silicone defoamer to the antifouling agent dispersion. Adjust the speed to 1000 r / min and continue stirring for 10 minutes to fully integrate the coating components and form a uniform coating base.

[0049] S5. Grinding and particle size detection: The above coating base material is fed into a sand mill for grinding. After grinding, a laser particle size analyzer is used to detect the particle size of the system to ensure that the particle size is ≤50μm.

[0050] S6. Sealed Curing: The qualified grinding coating base is sent into a sealed curing tank and cured at room temperature (20°C) for 2 hours to naturally eliminate residual air bubbles in the system and stabilize the performance of the coating system.

[0051] S7. Initial Inspection and Adjustment of Finished Product: After curing, the coating is initially inspected for appearance and viscosity. The coating has a uniform appearance without any abnormalities and the viscosity meets the construction requirements. No fine-tuning is required, and the final antifouling coating is obtained.

[0052] Performance testing: The coating has a uniform appearance, no bubbles, and no sediment; the coating adhesion (cross-cut test) is grade 0; the seawater erosion resistance (immersion for 30 days) shows no peeling or discoloration; the barnacle adhesion inhibition rate is ≥95%, and the bacterial inhibition rate is ≥96%; the antifouling effect lasts for ≥15 months; the biodegradability rate is ≥88%; no heavy metals were detected, meeting environmental protection requirements.

[0053] Comparison of proportions

Claims

1. An environmentally friendly antifouling coating based on the synergistic effect of natural products, comprising, by parts, 5-20 parts of a natural product antifouling agent, 30-50 parts of an environmentally friendly film-forming agent, 2-5 parts of a dispersant, 1-3 parts of a thickener, 0.5-2 parts of a defoamer, and 20-40 parts of an environmentally friendly solvent. The natural product antifouling agent is a compound of marine plant extracts and plant essential oils. The marine plant extracts are selected from at least one of seaweed polysaccharides, kelp extracts, and laver extracts. The plant essential oils are selected from at least one of peppermint oil, cinnamon oil, and tea tree oil. The mass ratio of the marine plant extracts to the plant essential oils is 1:1-3:

1. The coating is free of heavy metals and organotin compounds, and has a biodegradability rate ≥80%.

2. The environmentally friendly antifouling coating based on the synergistic effect of natural products according to claim 1, characterized in that, The amount of the natural product antifouling agent is 8 to 15 parts.

3. The environmentally friendly antifouling coating based on the synergistic effect of natural products according to claim 1, characterized in that, The environmentally friendly film-forming agent is selected from at least one of waterborne polyurethane film-forming agents and waterborne acrylic film-forming agents. It can be used alone or in combination. When in combination, the mass ratio of the two is 1:1 to 2:

1.

4. The environmentally friendly antifouling coating based on the synergistic effect of natural products according to claim 1, characterized in that, The dispersant is selected from at least one of sodium polycarboxylate and sodium lignosulfonate, the thickener is selected from at least one of xanthan gum and sodium carboxymethyl cellulose, and the defoamer is an organosilicon-based environmentally friendly defoamer, the main component of which is polydimethylsiloxane.

5. The environmentally friendly antifouling coating based on the synergistic effect of natural products according to claim 1, characterized in that, The environmentally friendly solvent is selected from at least one of deionized water and ethanol, with a preferred mixture of deionized water and ethanol in a ratio of 1:1 to 2:

1.

6. The environmentally friendly antifouling coating based on the synergistic effect of natural products according to claim 1, characterized in that, The coating exhibits an adhesion inhibition rate of ≥90% against barnacles, an antibacterial rate of ≥94% against bacteria, a stain-resistant duration of ≥11 months, and a coating adhesion (cross-cut test) grade of 0-1.

7. A method for preparing an environmentally friendly antifouling coating based on the synergistic effect of natural products as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Materials are accurately weighed and pre-treated, and each component is weighed in portions and impurities in the raw materials are removed. S2. Additive premixing: Add environmentally friendly solvent, dispersant, and thickener to a stirring device and stir at 500-800 r / min for 10-20 minutes at room temperature (20-25℃) to obtain a uniform mixture. S3. Antifouling agent dispersion: Add the natural product antifouling agent to the mixture, adjust the speed to 1000-1500 r / min and disperse at high speed for 20-30 minutes to ensure no agglomeration. S4. Mix the film-forming agent and defoamer. Add the environmentally friendly film-forming agent and defoamer to the dispersion and stir at 800-1000 r / min for 10-15 minutes. S5. Grinding: Grind the mixture until the particle size is ≤50μm; S6. Curing: Curing the ground system at room temperature (20-25℃) for 2-4 hours to obtain the antifouling coating. S7. Initial inspection and adjustment of finished product: After curing, the appearance and viscosity of the coating are initially inspected. If the viscosity does not meet the construction requirements, a small amount of environmentally friendly solvent can be added for fine adjustment to obtain the antifouling coating.

8. The preparation method according to claim 7, characterized in that, In step S5, a sand mill is used for grinding, and the grinding time is 15-25 minutes.

9. The preparation method according to claim 7, characterized in that, In step S7, the amount of environmentally friendly solvent added each time is ≤0.5 parts.

10. The application of the environmentally friendly antifouling coating based on the synergistic effect of natural products according to any one of claims 1-6, characterized in that, The coating is used for surface antifouling treatment of ship hulls, offshore platforms, and offshore wind turbine towers, and can be applied by brushing, rolling, or spraying.

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