Preparation method and application of anti-fouling coating system for preventing biological adhesion

Abstract

The invention discloses a preparation method and application of an anti-fouling coating system capable of preventing biological adhesion, the anti-fouling coating system capable of preventing biological adhesion comprises a primer and a topcoat, and the primer comprises a first component and a second component. According to the preparation method and application of the anti-fouling coating system capable of preventing biological adhesion, the anti-traditional thinking is used for developing an anti-fouling coating, the surface coating is used for developing a nano composite particle coating, a high-surface-energy nano material is firstly used as a basis, a dark catalytic electrolysis technology is matched for preparation, the characteristic of high surface energy of the nano material is adopted, and the anti-fouling coating system capable of preventing biological adhesion is prepared. Energy is absorbed, stored, converted and released through the composite nano-material, the nano-material breaks walls of marine microorganisms and a generated electric field effectively prevents generation of a biological membrane, then growth of marine bacteria, shells and benthic diatom is effectively inhibited, meanwhile, two-dimensional nano-graphene is adopted to replace traditional graphene oxide for modification, the overall engineering is simple, and the cost is low. More atoms are distributed on the surface, and the coating surface has higher energy.

Description

Technical Field

[0001] The present invention relates to the technical field of marine anti-corrosion and anti-fouling, and in particular to a preparation method and application of an anti-biological attachment anti-fouling coating system. Background Art

[0002] As we all know, the attachment of marine organisms to the surface of ships will not only significantly increase the weight of the hull, increase navigation resistance, reduce the speed of the ship, and thus increase fuel consumption, but will also accelerate the corrosion of the ship's bottom and shorten its service life. In order to reduce the harm of marine organism attachment and prevent marine organisms from fouling ships, people have studied a variety of anti-fouling technologies. In the past few decades, compounds such as mercury and arsenic were used to prepare anti-fouling coatings in the early days, but these substances were eliminated due to their toxicity and high pollution to the marine environment. Subsequently, anti-fouling paints were developed with cuprous oxide as the main toxic material and rosin, asphalt, ethylene resin and chlorinated rubber as the main base materials. Since 2 Since the 1960s, people have applied organotin compounds to antifouling coatings to extend the antifouling effect. However, these antifouling coatings contain toxic chemicals that can pollute the marine environment. Therefore, in recent years, new environmentally friendly marine antifouling coatings have been continuously introduced. From an environmental perspective, people hope to use pollution-free antifouling technologies to achieve the prevention and control of marine fouling organisms. Many countries are actively conducting research on long-term and pollution-free antifouling materials and technologies through various technical approaches. To date, major world-renowned coatings companies have made research investments in the research and development of new marine antifouling coatings and have also produced many research results.

[0003] Depending on the resin used, antifouling coatings can be divided into base material insoluble, controllable ablation and self-polishing types. Among them, self-polishing antifouling coatings, including copper acrylate polymer, zinc acrylate polymer and silane acrylate polymer-based antifouling coatings, currently dominate. The basic principle is to convert the polymer into a hydrophilic polymer through the hydrolysis of the side chain, which then dissolves under the scouring of seawater to release the antifouling agent. However, since only the side chains in its structure can undergo hydrolysis, it is difficult to control the synergy of polymer hydrolysis and dissolution, making its self-polishing property dependent on the movement of the ship and the scouring of surrounding seawater, which makes it difficult to meet the requirements of static antifouling. At the same time, existing self-polishing polymer systems themselves do not have antifouling functions and can only rely on the release of antifouling agents to inhibit fouling organisms. However, existing antifouling agents are effective in killing fouling organisms, but are powerless against the adhesion of biomacromolecules such as proteins and polysaccharides in the early stages of the fouling process. Existing self-polishing resins are vinyl polymers that cannot be degraded under natural conditions, resulting in the problem of "plastic waste pollution" in the ocean.

[0004] In 2023, South China University of Technology published a patent for "A self-polishing zwitterionic antifouling resin with main chain degradability and its preparation and application." Although the patent results have been evaluated as reaching international leading levels, they have not yet solved the problems of high temperature, high salt and static antifouling.

[0005] In 2023, a research team at the University of Hong Kong published a patent for a "photocatalytic marine antifouling and anticorrosion coating." This innovative approach addresses the vulnerability of ships and marine facilities to biofouling and corrosion. Photocatalytic cathode nanocomposites can be used to create protective coatings that offer significant marine antifouling and anticorrosion effects without adversely affecting marine organisms. However, the complexities of photoelectrocatalysis in the absence of sunlight have not been addressed.

[0006] The invention with publication number CN110128943A, "A Long-lasting Anticorrosive Graphene-Modified Solvent-Free Epoxy Coating and Preparation Method thereof," utilizes a polyurethane structure to chemically graft graphene oxide microplatelets onto epoxy molecular chains. This aims to enhance the high specific surface area of ​​graphene, fully demonstrating its super-hydrophobic and high shielding properties. With the increasing popularity of nanographene, its advantages of a larger specific surface area and a greater number of effective atoms, as well as higher surface energy, offer superior performance compared to graphene oxide.

[0007] However, current antifouling products have problems such as short antifouling time, low antifouling efficiency, and harm to marine life and marine ecology. Wuxi self-polishing antifouling coatings, low surface energy antifouling coatings, and photocatalytic antifouling coatings have failed to address static antifouling and the changes in complex environmental factors. Summary of the Invention

[0008] The main purpose of the present invention is to provide a preparation method of an anti-biological adhesion anti-fouling coating system and its application, which can effectively solve the problems in the background technology.

[0009] To achieve the above object, the technical solution adopted by the present invention is:

[0010] A method for preparing an antifouling coating system for preventing biofouling, the antifouling coating system comprising a graphene solvent-free epoxy coating base material and a finished nanographene solvent-free epoxy paint; a topcoat comprising nanocomposite particles, comprising the following steps:

[0011] S1: Preparation of graphene solvent-free epoxy coating base:

[0012] A: Prepare the first component and the second component, wherein the first component includes the following raw materials in parts by weight:

[0013] The first component has a total solid content of ≥97%, including: 50-80% solvent-free epoxy resin, 1-5% wetting and dispersing agent, 1-40% anti-rust pigment, 1-5% defoaming agent, 1-5% leveling agent, 1-5% thickener, and 0.1-2% nanographene;

[0014] The second component is an epoxy curing agent;

[0015] B: According to the weight ratio of the formula, the wetting and dispersing agent, anti-rust pigment, thickener, and leveling agent are added to the solvent-free epoxy resin in proportion at one time, and the mixture is ground using a sand mill at room temperature with the speed controlled at 1000-2500 r / min for 2-5 hours. During the grinding process, the defoamer is added in batches, and the amount is controlled to not exceed 5% of the total formula. The mixture is ground to a fineness of less than 50 μm, and filtered and packaged using a filter to obtain a solvent-free epoxy coating base.

[0016] C: Mix nanographene and industrial ammonia in a ratio of 1:5, disperse with ultrasound for 2-3 hours, and dehydrate and dry to obtain a modified graphene base material;

[0017] D: directly adding 0.1-2% of the modified graphene base material to 100% of the solvent-free epoxy coating base material and mixing and stirring to obtain the graphene solvent-free epoxy coating base material;

[0018] S2: Prepare the finished nano-graphene solvent-free epoxy paint. Before painting, mix the graphene solvent-free epoxy paint base material and the epoxy curing agent in a ratio of 100%:15-25% to obtain the graphene solvent-free epoxy paint. Stir and mature for 20-30 minutes before use.

[0019] S3: Preparation of nanocomposite particle antifouling topcoat: wherein the nanocomposite particle antifouling topcoat comprises, according to the weight ratio of the formula, 30-50 parts of nano-cuprammonia fiber, 10-30 parts of nano-Power Rock paramagnetic ore, 10-30 parts of nano-graphene, and 30-50 parts of nano-tourmaline. The preparation method comprises the following steps:

[0020] 1. Prepare nanobubble water, industrial ammonia water, and composite nanoparticles in a ratio of 95:5:1, wherein the nanocomposite nanoparticles have a fineness of <10 nm. The industrial ammonia water is composed of 25-28% NH3·H2O. The nanobubble water uses a nanobubble generator to generate negatively charged nanobubbles of 100 nm. The nanobubble water functions as a surfactant.

[0021] 2. Processing of composite nanoparticle dispersant: Add nano bubble water and industrial ammonia water into the nano composite nanoparticles 2-4 times, mix and stir for 5-10 minutes to prepare the nano composite particle dispersion.

[0022] Preferably, in the first component of step S1, the solvent-free epoxy resin is any one of low molecular weight modified bisphenol A epoxy, low molecular weight modified bisphenol F epoxy, low molecular weight alicyclic epoxy, and low molecular weight phenolic modified epoxy resin, or a combination of multiple resins; the wetting dispersant is a solvent-free associative polyurethane or a solvent-free acrylic dispersant; the rust-proof pigment is any one of zinc phosphate, aluminum tripolyphosphate, glass flakes, iron red, and zinc powder, or a combination of multiple resins; the defoamer is an organosilicon defoamer containing hydrophobic ions; the thickener is any one of organic clay, fumed silica, and polyamide thickener; and the nanographene is a two-dimensional structure below 10 nm.

[0023] Preferably, in the second component in step S1, the curing agent is any one or more of diethylenetriamine, triethylenetetramine, triethylaminopropylamine, tetraethylenepentamine, menthanediamine, isophoronediamine, diaminodiphenyl sulfone, and diaminodiphenylmethane.

[0024] Preferably, in step S2, the weight ratio of the first component to the second component is 100%:15-25%, and the total solid content of the sum of the first component and the second component is ≥97%.

[0025] Preferably, in step S3, the nanographene is two-dimensional nanographene, and nanographene particles of 2-3 nm are selected; the cuprammonium fiber is non-Li-type cuprammonium fiber; and the nano Power Rock paramagnetic ore is of 2-3 nm.

[0026] An application of an anti-fouling coating system for preventing biofouling is applied to the surface of a marine vessel. The anti-fouling coating system for preventing biofouling includes a primer and a topcoat, and includes the following construction and application steps:

[0027] a. Mix the graphene solvent-free epoxy coating base and the curing agent in a ratio of 100%:15-25% and stir evenly to obtain the graphene solvent-free epoxy coating, and ripen it for 20-30 minutes. The coating thickness is 100-200 microns;

[0028] b: After the primer nano-graphene solvent-free epoxy paint is applied but before the surface is dry, the nano-composite particle anti-fouling topcoat fluid is immediately sprayed with a nano-spray gun for topcoating, implementing the nano-material wet-on-wet coating process.

[0029] Beneficial effects

[0030] This invention, with unconventional thinking, develops a nanocomposite particle coating, pioneering dark catalytic electrolysis technology, pushing back against the conventional concept of low-surface-energy antifouling paints. This new coating utilizes nanomaterials with piezoelectric and thermoelectric effects. Leveraging the high surface energy of nanomaterials, the composite absorbs external energy through their piezoelectric and thermoelectric effects, while nanographene stores the energy and converts the absorbed electrical and light energy into infrared energy. This energy difference then generates convection and releases the energy onto the coating surface. The nanomaterials disrupt the surface of marine microorganisms, and the electric field they generate effectively prevents biofilm formation, thereby effectively inhibiting the growth of marine bacteria, shells, and benthic diatoms. The ocean rises and falls every day as the Earth and the Moon travel farther. The flow of seawater and the impact of water currents produce non-stop kinetic energy. The heat produced by the sun creates a temperature difference between the atmosphere and the water. The transfer of heat generates thermal energy. When the movement and conversion of energy come into contact with nanomaterials, piezoelectric and thermoelectric effects are generated. Composite nanomaterials absorb, store and release energy, and through the energy conversion process, it is converted into electrical energy and magnetic field. The piezoelectric and thermoelectric effects allow dark catalysis technology to play an anti-fouling role in catalytic sterilization in the absence of sunlight. As long as there is water flow and Temperature difference, dark catalysis can generate energy at any time and anywhere, without geographical and time restrictions, using conductive nanoparticle paint as the anode to electrolyze seawater, and directly using seawater as the electrolyte for electrolysis, chlorine is generated at the anode, and chlorine reacts with seawater to produce hypochlorite. The generated chlorine and hypochlorite are used to prevent the formation of biofilms, and the living environment of marine microorganisms cannot be formed, and they automatically leave to find other suitable places to grow. Basically, this technology does not eliminate marine microorganisms, but drives away marine microorganisms by preventing the formation of biofilms, thereby having excellent anti-fouling properties.

[0031] Using two-dimensional nanographene instead of traditional graphene oxide for modification, we produce a heavy-duty, corrosion-resistant graphene solvent-free paint. Its advantages include simple engineering, a larger specific surface area, more atoms distributed on the surface, and higher energy on the coating surface. This solvent-free epoxy heavy-duty anti-corrosion paint uses two-dimensional nanographene instead of traditional graphene oxide for modification. A 100-micron film can pass a 10,000-hour salt spray test. Because the coating surface is fully covered with two-dimensional nanographene, the coefficient of dynamic friction with water is as low as 0.15, significantly reducing fuel costs and achieving excellent energy savings.

[0032] Traditional antifouling paints use self-polishing SPC or antifouling paints based on low surface energy silicone. These materials focus on low surface energy. Low surface energy not only affects the adhesion between the paint and the substrate, but also requires the ship to move for effective antifouling. This is a passive antifouling method and is less effective for static antifouling. This antifouling system, on the other hand, uses high surface energy nanomaterials with piezoelectric and thermoelectric effects. The electric field generated on the surface of the nanomaterials can actively inhibit and repel microorganisms and algae, making it an active antifouling method that is not affected by dynamic or static antifouling environments.

[0033] The antifouling coating system uses a newly developed nano-graphene solvent-free epoxy paint. The coating film thickness of 100-200 microns can pass the salt spray test for more than 5000-10000 hours. Nano-graphene not only increases the anti-corrosion performance, but also improves the adhesion between the paint and the hull.

[0034] Nanocomposite materials can modify graphene solvent-free epoxy paint, increasing its hardness, wear resistance and corrosion resistance by several times. Nanocomposite particles can repel liquids at the scale of cubic nanometers. No matter what surface it is used on, it can tightly adhere to the porous structure, thus forming a finer network in these pores. This structure also means that 95%-99% of the coating forms air bags, so any liquid that contacts the coating can hardly touch its solid surface. Since the liquid can only contact the filaments on the surface of the fabric coating, the intermolecular force is greatly reduced. When the two materials are close enough, they will be affected by the positive or negative charge of each other. If it is solid-liquid contact, the liquid will enter the solid and diffuse. This nanocoating greatly reduces the interaction between the solid surface and the droplets, which is also the reason why the friction coefficient of nanomaterials is low.

[0035] Graphite itself is a lubricating material. When nano-graphene is added to the surface coating, the friction coefficient drops from 0.5 of traditional SPC paint to 0.15, which is a significant reduction, and the energy consumption cost is naturally reduced.

[0036] The top coating is made of composite nanomaterial particles, using a new wet-on-wet coating technology. The nanocomposite particles are dispersed in an aqueous solution. When the graphene solvent-free epoxy paint in the middle begins to cure but is not completely cured, a nano-spray gun is used to spray a water-based nanomaterial dispersant. Based on the principle of water-oil incompatibility, the water is drained away, and the entire top coating surface is 100% covered with nanocomposite particles, thus producing the highest electrolysis effect.

[0037] Thanks to nano-scale materials, materials below 10nm are selected, preferably 2-5nm nanomaterials, mainly including cuprammonium fiber, Power Rock, graphene and tourmaline. Nanoparticles can also effectively inhibit the attachment of fouling organisms through the active groups generated. Their fineness can break the wall and enter the microbial cells, destroying cell tissues. They have antibacterial, bactericidal and sterilization functions, effectively preventing microorganisms from secreting sticky substances on the surface of anti-fouling materials, isolating and destroying the ecological environment of microorganisms. The use of cuprammonium fiber is due to its wear resistance and conductive properties. The fiber produces a three-dimensional interwoven structure, which firmly combines the nano-composite particles with the graphene epoxy paint.

[0038] The surface coating of composite nanomaterial particles adopts a new dispersion modification process. The new dispersion modification process uses nanomaterials and adds ammonia nanoparticles generated by nanobubbles. The characteristics of nanobubble water can reduce the solid-liquid interfacial energy. Secondly, the nanobubbles themselves have the characteristic of negative charge. Under the principle of like polarity repulsion, they hinder the mutual collision between nanoparticles, making it difficult for them to agglomerate, and the nanoparticles can be stably dispersed in the nanobubble fluid. The use of nanobubble dispersion technology is a new nanomaterial dispersion process. This invention uses nanocomposite materials to be immersed in industrial ammonia water for dispersion, and then adds nanobubble water to obtain a nanomaterial particle dispersion liquid. It can be stored stably for a long time and is convenient for later construction. The purely physical dispersion process does not produce any chemical reaction and maintains the function of nanomolecules, which not only reduces costs but also has long-term effectiveness.

[0039] The self-prepared nanobubbles combined with ammonia modification and nanocomposites are simple and quick, and significantly improve the dispersibility and storage stability of nanocomposites, solving the problems of difficult dispersion, easy aggregation, and storage period of nanocomposites in coatings.

[0040] Adding graphene to coatings can improve the coating's heat resistance, impact resistance and wear resistance. Graphene flakes will be oriented and overlapped during the drying process of the coating, effectively shielding H2O, CO2, Cl-, etc., creating a "maze effect." 200-micron thickness has passed the salt spray test for more than 10,000 hours. The topcoat with added graphene has a lubricating effect, and the friction coefficient has dropped significantly from 0.5 to 0.15, which is of great help to ship energy conservation and emission reduction. Epoxy coatings are not resistant to aging and ultraviolet damage. When solvent-free epoxy is modified with nanoparticles, the weather resistance is greatly improved. After 2,000 hours of aging and weathering tests, the coating is completely intact and only loses 2 degrees of gloss. The use of materials below 10nm increases the activity of the material, effectively preventing biological attachment, with static anti-fouling for more than 3 years and dynamic anti-fouling for more than 7 years. It utilizes the energy of nature and the breakthrough of dark catalysis technology, which is not restricted by time and environment, and solves the application of many scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a test report diagram of the first specific embodiment of the present invention;

[0042] Figure 2 This is a test report diagram of the coefficient of kinetic friction according to the first specific embodiment of the present invention;

[0043] Figure 3 This is a report diagram of the acute oral toxicity test results of the first specific embodiment of the present invention;

[0044] Figure 4 This is a diagram showing a heavy metal toxicity test report for a coating according to a first specific embodiment of the present invention;

[0045] Figure 5 This is a microbial detection report diagram of the first specific embodiment of the present invention. DETAILED DESCRIPTION

[0046] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0047] A method for preparing an antifouling coating system for preventing biofouling, the antifouling coating system comprising a graphene solvent-free epoxy coating base material and a finished nanographene solvent-free epoxy paint; a topcoat comprising nanocomposite particles, comprising the following steps:

[0048] S1: Preparation of graphene solvent-free epoxy coating base:

[0049] A: Prepare the first component and the second component, wherein the first component includes the following raw materials in parts by weight:

[0050] The first component has a total solid content of ≥97%, including: 50-80% solvent-free epoxy resin, 1-5% wetting and dispersing agent, 1-40% anti-rust pigment, 1-5% defoaming agent, 1-5% leveling agent, 1-5% thickener, and 0.1-2% nanographene;

[0051] The solvent-free epoxy resin is any one of low molecular weight modified bisphenol A epoxy, low molecular weight modified bisphenol F epoxy, low molecular weight alicyclic epoxy, low molecular weight phenolic modified epoxy resin, or a combination of multiple resins; the wetting and dispersing agent is a solvent-free associative polyurethane or a solvent-free acrylic dispersant; the anti-rust pigment is any one of zinc phosphate, aluminum tripolyphosphate, glass flakes, iron red, and zinc powder, or a combination of multiple resins; the defoamer is an organosilicon defoamer containing hydrophobic ions; the thickener is any one of organic clay, fumed silica, and polyamide thickener; and the nanographene is a two-dimensional structure less than 10 nm in size.

[0052] The second component is an epoxy curing agent, wherein the curing agent is any one or more of diethylenetriamine, triethylenetetramine, triethylaminopropylamine, tetraethylenepentamine, menthanediamine, isophoronediamine, diaminodiphenyl sulfone, and diaminodiphenylmethane;

[0053] The weight ratio of the first component to the second component is 100%:15-25%, and the total solid content of the first component and the second component is ≥97%;

[0054] B: According to the weight ratio of the formula, the wetting and dispersing agent, anti-rust pigment, thickener, and leveling agent are added to the solvent-free epoxy resin in proportion at one time, and the mixture is ground using a sand mill at room temperature with the speed controlled at 1000-2500 r / min for 2-5 hours. During the grinding process, the defoamer is added in batches, and the amount is controlled to not exceed 5% of the total formula. The mixture is ground to a fineness of less than 50 μm, and filtered and packaged using a filter to obtain a solvent-free epoxy coating base.

[0055] C: Mix nanographene and industrial ammonia in a ratio of 1:5, disperse with ultrasound for 2-3 hours, and dehydrate and dry to obtain a modified graphene base material;

[0056] D: directly adding 0.1-2% of the modified graphene base material to 100% of the solvent-free epoxy coating base material and mixing and stirring to obtain the graphene solvent-free epoxy coating base material;

[0057] S2: Prepare the finished nano-graphene solvent-free epoxy paint. Before painting, mix the graphene solvent-free epoxy paint base material and the epoxy curing agent in a ratio of 100%:15-25% to obtain the graphene solvent-free epoxy paint. Stir and mature for 20-30 minutes before use.

[0058] S3: Preparation of nanocomposite particle antifouling topcoat: wherein the nanocomposite particle antifouling topcoat comprises, according to the weight ratio of the formula, 30-50 parts of nano-cuprammonia fiber, 10-30 parts of nano-Power Rock paramagnetic ore, 10-30 parts of nano-graphene, and 30-50 parts of nano-tourmaline. The preparation method comprises the following steps:

[0059] 1. Prepare nanobubble water, industrial ammonia water, and composite nanoparticles in a ratio of 95:5:1, with the nanocomposite nanoparticles having a particle size of <10 nm. The industrial ammonia water is composed of 25-28% NH₃·H₂O. The nanobubble water uses a nanobubble generator supplied by Inch Water Co. Ltd. (Hong Kong) to generate negatively charged nanobubbles (100 nm in diameter). The nanobubble water functions as a surfactant.

[0060] 2. Processing of composite nanoparticle dispersant: Add nanobubble water and industrial ammonia water to nanocomposite nanoparticles 2-4 times, mix and stir for 5-10 minutes to prepare nanocomposite particle dispersion. Compared with adding industrial ammonia water all at once, adding it in stages can control the reaction rate, generate more growth cores, and thus reduce the particle size. The surface of the dispersed nanocomposite particles is coated with a layer of ammonia water film, so that the nanocomposite particles are dispersed in the ammonia water-soluble solid phase carrier. This solid phase carrier is coated with nanobubbles. The surface of the nanobubbles themselves has a negative charge. According to the principle of like charges repel each other, the nanobubbles repel each other, so the nanocomposite particles can be stably and permanently dispersed in the nanobubble ammonia water.

[0061] Nanographene is two-dimensional nanographene, using nanographene particles of 2-3nm. Cuprammonium fiber is non-ionic cuprammonium fiber, and nano Power Rock paramagnetic ore is 2-3nm. Tourmaline has the characteristics of piezoelectricity, pyroelectricity and permanent spontaneous polarization. The spontaneous polarization phenomenon occurs because the tourmaline crystal has a non-centrosymmetric unidirectional polar axis. Due to the presence of unbonded lone pairs of electrons and free positive ions in the crystal structure, the positive and negative polarity centers in the crystal structure do not coincide, resulting in permanent electrical polarity. The existence of permanent electrical polarity causes a certain amount of floating opposite polarity charges to accumulate around the unit cell. When the temperature changes or pressure is applied, the energy and structural position within the crystal change. The opposite polarity charges can easily break away from their original position, causing the positive and negative charges to be redistributed. The overall dipole moment of the crystal changes, which strengthens the strength of the spontaneous electric field, thereby leading to the occurrence of pyroelectricity and piezoelectricity.

[0062] The permanent spontaneous electrode effect of tourmaline can cause a weak electrolysis of water molecules in the surrounding air H2O→H + +OH - , seawater NaCl→Na + +Cl - , hydrogen ions gain electrons 2H from the weak current between tourmaline electrodes + +2e→H2, hydroxide ions combine with water molecules to form air negative ions OH - +nH2O→OH - (H2O)n; Under the same conditions, the more tourmaline is added and the finer the particle size, the greater the absolute value of its Zeta potential, the higher the negative ion release, and the more obvious the inhibition of the growth of bacteria, microorganisms and diatoms.

[0063] Tourmaline has a spontaneous polarization effect, which creates a strong electrostatic field on its surface, thus having a mechanism similar to electrochemical antifouling methods. Tourmaline can release negative ions, which themselves have a bactericidal effect. Tourmaline can change the amount of dissolved oxygen in water, making it difficult for anaerobic organisms to attach. The thermogenic effect of the far-infrared rays produced by tourmaline may affect the local ambient temperature, thereby inhibiting the growth of cells with poor high temperature tolerance.

[0064] Nanographene is not graphene oxide (GO), modified graphene oxide, or graphite. Nanographene has a very high specific surface area and a large number of surface atoms, resulting in strong interfacial activity. Nanographene is used instead of graphene oxide to enhance the anti-corrosion ability of epoxy paint, forming graphene block flake polymers. This achieves chemical bonding between graphene flakes and the epoxy paint matrix, allowing them to be fully oriented in the resin matrix, forming a maze effect, and giving full play to the shielding properties of the graphene flakes, greatly improving the corrosion protection performance of the coating.

[0065] Cuprammonia fiber is a non-lined cuprammonia fiber, which is safe and harmless to the human body. Copper nitrogen fiber is an environmentally friendly regenerated cellulose fiber. Non-petroleum raw materials are used in its processing. Even if it is burned, it will not produce toxic gases, so there is no damage to the ecological environment. These characteristics of cuprammonia fiber make it a fiber material with excellent environmental performance. The advantages of cuprammonia fiber include good moisture absorption and breathability, antistatic properties, drape, strength, silk texture, smooth fabric, alkali resistance, bright color and high color fastness, antibacterial and sterilization, good electrical conductivity, and strong wear resistance. Non-lined cuprammonia fiber is not only safe and harmless to the human body but also has a variety of excellent properties, making it an ideal environmentally friendly antibacterial coating. Cuprammonia fiber has a fiber network characteristic, which constitutes a three-dimensional structure of surface nano-molecules, which greatly improves the adhesion of surface nano-material particles.

[0066] Power Rock paramagnetic ore is a unique paramagnetic material. Although it is not magnetic itself, it is magnetized in the presence of a magnetic field or substance. The collective force of the paramagnetic ore particles generates a non-polar magnetic field, which brings rapid molecular organization of the same polarity to the seawater around the coating, strengthening and accelerating the effect of the electromagnetic field.

[0067] Nanobubble ammonia refers to a nanobubble ammonia mixture produced by mixing ionized water and ammonia through a nanobubble generator. The nanobubbles in the water have a negative charge on their surface. The nanobubbles move left and right, functioning as surfactants. Composite nanomaterial molecules are adsorbed by the nanobubbles, reducing the interfacial energy between the nanoparticles and water. At the same time, the surface of the nanoparticles becomes hydrophilic. The negative electrode properties of the nanobubbles prevent the nanoparticles from colliding with each other, making it difficult for them to agglomerate. They are then stably dispersed in the nanofluid, resulting in a stable modified composite nanoparticle dispersant.

[0068] An application of an anti-fouling coating system for preventing biofouling is applied to the surface of a marine vessel. The anti-fouling coating system for preventing biofouling includes a primer and a topcoat, and includes the following construction and application steps:

[0069] An application of an anti-fouling coating system for preventing biofouling is applied to the surface of a marine vessel. The anti-fouling coating system for preventing biofouling includes a primer and a topcoat, and includes the following application steps:

[0070] a: Mix the graphene solvent-free epoxy coating base and curing agent in a ratio of 100%:15-25% and stir evenly to obtain the graphene solvent-free epoxy coating. Cure it for 20-30 minutes before applying the primer. The coating thickness is 100-200 microns. Nanographene increases the anti-corrosion performance of the base layer and improves the adhesion to the hull.

[0071] b: Nano-graphene solvent-free epoxy paint modifies the paint, and its hardness, wear resistance, and anti-corrosion performance are more than doubled. Graphite itself is a lubricating material. After nano-scaling, the friction coefficient is reduced from 0.5 of traditional paint to 0.15, significantly reducing energy consumption costs;

[0072] c: Use a nano spray gun to spray the nano-composite particle anti-fouling topcoat fluid for top coating. Disperse the nano-composite particle anti-fouling topcoat in an aqueous solution. When the primer graphene solvent-free epoxy begins to cure but is not completely cured, spray the composite nano-material particle fluid. Using the principle of water-oil incompatibility, the entire primer surface is covered with nano-composite molecules, thereby producing the highest electrolysis effect. Specific embodiment one:

[0074] Graphene solvent-free epoxy coating base material formula:

[0075] The first component is a low molecular weight modified bisphenol A epoxy resin with a total solid content of 100%, of which the epoxy resin solid content is 80%;

[0076] The second component curing agent is diethylenetriamine;

[0077] Solid content of the first component + the second component ≥ 97%;

[0078] Component 1: Component 2 = Graphene solvent-free epoxy paint: curing agent = 5:1

[0079] Nanographene is at the 10nm level;

[0080] Graphene solvent-free epoxy coating base material is added with 2% modified graphene base material;

[0081] The formula ratio of nano materials for antifouling topcoat is: cuprammonium fiber 40%, tourmaline 40%, Power Rock 10%, graphene 10%. The nanometer fineness is ≦10nm, such as Figure 1-5 As shown, it is the test items and test results. Specific embodiment two:

[0083] Selection of nanomaterials with different particle sizes: Based on the original antifouling paint nanomaterials, different particle sizes were selected, namely 10,000 mesh (1.3 μm), 30,000 mesh (100 nm), and 10 nm. Experimental measurement was conducted on negative ion release rate, zeta potential, colony count, and chlorophyll.

[0084] Test conclusion:

[0085] 1. The finer the nanomaterial particles, the higher the negative ion release rate, and it indicates that the selected nanomaterial has the ability to release negative ions;

[0086] 2. The finer the particle size, the greater the absolute value of the zeta potential;

[0087] 3. The finer the particle size, the less total colony count and the lower the chlorophyll release, which indicates that the nanomaterials effectively kill bacteria and inhibit the growth of benthic diatoms. Specific embodiment three:

[0089] Using a 10nm nanomaterial particle size, the nanomaterial was added to nanobubble ammonia water at varying mass ratios; the nanomaterial dosages of 1%, 2%, and 5% were mixed with the nanobubble ammonia water to produce a nanocomposite particle dispersion. The negative ion release rate, zeta potential, colony count, and chlorophyll were experimentally measured.

[0090] Test conclusion:

[0091] 1. The more nanomaterials are used, the higher the negative ion release rate is, and it indicates that the selected nanomaterials have the ability to release negative ions;

[0092] 2. The more the dosage, the greater the absolute value of zeta potential;

[0093] 3. The more the dosage is used, the faster the total colony count decreases and the lower the chlorophyll release is. This shows that the efficiency of nanomaterials in sterilization and algae inhibition is significantly improved. Specific embodiment four:

[0095] A nanomaterial particle size of 10nm was selected, and the nanomaterial dosage was 1%. 1% of the nanomaterial was added to nanobubble ammonia water to produce a nanobubble ammonia dispersion. Another group added 1% of the nanomaterial to fluorocarbon paint and stirred it evenly to produce a nanofluorocarbon paint. The nanobubble ammonia dispersion was sprayed onto the solvent-free surface of the graphene primer. After the water was drained, the nanoparticles completely covered the surface of the midcoat, forming a 100% nanoparticle coating. Another group sprayed nanofluorocarbon paint directly onto the surface of the primer to form a topcoat. The topcoat consisted of 100% fluorocarbon paint and 2% nanocomposite particles. Experimental measurements were performed on negative ion release rate, zeta potential, colony count, and chlorophyll.

[0096] Test conclusion:

[0097] 1. After the nano dispersion is sprayed, the surface is fully covered with nano materials, and the negative ion release is obviously many times higher than that of nano fluorocarbon paint;

[0098] 2. The absolute value of zeta potential of nano-dispersion is much larger than that of nano-fluorocarbon paint;

[0099] 3. It was found that the nano-dispersion accelerated the gradual decrease in the total colony count and the lower the chlorophyll release, which shows that the nano-dispersion has a higher coverage rate of nanomaterials. Thanks to the high conductivity of graphene, it can produce faster and higher electricity. Fluorocarbon resin is an insulator and affects the transmission of the electric field. This shows that the construction process affects the efficiency of nanomaterials.

[0100] The anti-fouling principle of this innovative technology combines multiple technologies, including 1. nanomaterial technology, 2. electrolysis technology, 3. dark catalysis technology, 4. nanobubble dispersion technology, 5. graphene coating technology, and 6. nanomolecular wet-on-wet coating technology:

[0101] 1. Nanomaterial technology: When the nanomaterial reaches a fineness of less than 10nm, its nanoparticles wrap around bacterial cells and have a contact-type antibacterial effect. Its bactericidal mechanism is that the positively charged antibacterial components can adsorb each other after contacting the negatively charged microbial cells, and effectively penetrate the cell nucleus, causing the cell protein to denature, unable to breathe, metabolize and reproduce, until death. Another way is to destroy the bacterial cells by wrapping them and breaking the wall excessively, or the bacterial cells are wrapped and cannot absorb external nutrients, leading to death. Since the nanoparticles are not consumed, they still maintain their original antibacterial ability, so they have a long-lasting antibacterial effect. Nanoparticles effectively inhibit the attachment of fouling organisms through the active groups they produce. Their fineness can break the wall into microbial cells and destroy cell tissues. They have antibacterial, bactericidal, and sterilization functions, effectively preventing microorganisms from secreting sticky substances on the surface of anti-fouling materials, isolating and destroying the ecological environment of microorganisms.

[0102] Epoxy coatings are not resistant to damage from aging ultraviolet rays. When solvent-free epoxy is modified with nanoparticles, its weather resistance is greatly improved. After 2000h of aging and weathering test, the coating is completely intact and only loses 2 degrees of gloss.

[0103] The use of materials below 10nm nanometers increases the activity of the materials, effectively preventing biological attachment, and providing static anti-fouling for more than 3 years and dynamic anti-fouling for more than 7 years.

[0104] 2. Electrolysis technology: The metal shell of the ship is coated with an insulating coating, nano-graphene solvent-free epoxy coating, which has the function of insulation and corrosion resistance. Then a layer of conductive coating and nano-composite particles are applied. The conductive coating is used as the anode and seawater is used as the electrolyte. The seawater is electrolyzed to achieve the purpose of anti-fouling through the chlorine and hypochlorite generated at the anode.

[0105] Seawater: NaCl → Na + +Cl - ;

[0106] Anode: 2Cl-→Cl2+2e- The anode produces chlorine gas and electrons;

[0107] Cathode: 2H2O+2e - →H2+OH - ;

[0108] Solution: Cl2+H20→HClO+Cl - +H + ;

[0109] Overall reaction: Cl - +H2O→ClO - +H 2 ;

[0110] Chlorine reacts with seawater to produce hypochlorite, which is then used to repel marine microorganisms.

[0111] 3. Dark catalytic technology: Photocatalysis has been a hot research topic in recent years. Under photothermal conditions, the activity of photoelectrons promotes catalytic reactions to disinfect, sterilize, and remove odors. Its advantage is that the energy comes from nature, but its disadvantage is that catalysis cannot proceed without sunlight energy. There are many different forms of energy in the natural environment. The problem is how to collect, store, release, and convert energy. This technology uses anti-traditional thinking to develop nano-composite particle coatings and is the first to use dark catalytic electrolysis technology to overturn the concept of traditional low-surface-energy antifouling paints. The new coating direction uses the high surface energy characteristics of nanomaterials to absorb, store, and release energy through composite nanomaterials. Nanomaterials can effectively prevent the formation of biofilms by breaking the walls of marine microorganisms and generating electric fields, thereby effectively inhibiting the growth of marine bacteria, shells, and benthic diatoms. The ocean has tides every day as the earth and the moon travel far away; the flow of seawater and water The impact of the flow generates non-stop kinetic energy; the heat produced by the sun creates a temperature difference between the atmosphere and the water, and the transfer of heat generates thermal energy. When the movement and transformation of energy come into contact with nanomaterials, piezoelectric and thermoelectric effects are generated. Composite nanomaterials absorb, store and release energy, and after the energy conversion process, it is converted into electrical energy and magnetic field. The piezoelectric and thermoelectric effects allow dark catalysis technology to play an anti-fouling role in catalytic sterilization in the absence of sunlight. As long as there is water flow and temperature difference, dark catalysis can generate energy at any time and anywhere, without geographical or time restrictions. Conductive nanoparticle paint is used as the anode to electrolyze seawater, and seawater is directly used as the electrolyte for electrolysis. Chlorine is generated at the anode, and chlorine reacts with seawater to produce hypochlorite. The generated chlorine and hypochlorite are used to prevent the formation of biofilms, and the living environment of marine microorganisms cannot be formed, and they automatically leave to find other suitable places.

[0112] By utilizing the energy of nature, the breakthrough of dark catalysis technology is not restricted by time and environment, and solves the application problems in many scenarios.

[0113] 4. Graphene coating: Graphene solvent-free epoxy paint is the anti-corrosion coating for this system. Graphene has excellent electrical and thermal conductivity of 5300W / MK and a unique two-dimensional single-layer structure. In addition to its large specific surface area creating a "maze effect" that effectively provides anti-corrosion, its two-dimensional single-layer structure acts as a "crystal cavity," allowing electricity and heat to move to the two sides of the surface layer rather than conducting heat inward, providing insulation protection.

[0114] Adding graphene to coatings can improve the coating's heat resistance, impact resistance and wear resistance. During the drying process of the coating, the flake-shaped graphene will be oriented and overlap with each other, effectively shielding H2O, CO2, Cl-, etc., creating a "maze effect". A coating with a thickness of 100 microns has passed the test and is resistant to salt spray for more than 5000 hours.

[0115] The topcoat with added graphene has a lubricating effect, and the friction coefficient is greatly reduced from 0.5 to 0.15, which is of great help to energy conservation and emission reduction of ships.

[0116] 5. Nanobubble Dispersion Technology: This invention utilizes self-prepared nanobubbles combined with ammonia-modified graphene. This simple and rapid method significantly improves graphene dispersibility and storage stability, resolving issues such as graphene's difficulty dispersing in coatings, its tendency to aggregate, and its limited shelf life. This purely physical dispersion process, devoid of any chemical reaction, maintains the functionality of the nanomolecules, reducing costs and ensuring long-term effectiveness.

[0117] 6. Nano-molecular wet-on-wet coating technology: A nano-spray gun is used to spray a nano-composite anti-fouling topcoat fluid for topcoating. The nano-composite anti-fouling topcoat is dispersed in an aqueous solution. When the primer, graphene solvent-free epoxy, begins to cure but is not completely cured, the composite nano-material particle fluid is sprayed on. Utilizing the principle of water-oil incompatibility, the entire primer surface is covered with nano-composite molecules, thus achieving the highest electrolysis effect.

[0118] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an antifouling coating system for preventing biofouling, the antifouling coating system comprising a graphene solvent-free epoxy coating base material and a finished nanographene solvent-free epoxy paint; a topcoat comprising nanocomposite particles, characterized in that: The following steps are included: S1: Preparation of graphene solvent-free epoxy coating base: A: Prepare the first component and the second component, wherein the first component includes the following raw materials in parts by weight: The first component has a total solid content of ≥97%, including: 50-80% solvent-free epoxy resin, 1-5% wetting and dispersing agent, 1-40% anti-rust pigment, 1-5% defoaming agent, 1-5% leveling agent, 1-5% thickener, and 0.1-2% nanographene; The second component is an epoxy curing agent; B: According to the weight ratio of the formula, the wetting and dispersing agent, anti-rust pigment, thickener, and leveling agent are added to the solvent-free epoxy resin in proportion at one time, and the mixture is ground using a sand mill at room temperature with the speed controlled at 1000-2500 r / min for 2-5 hours. During the grinding process, the defoamer is added in batches, and the amount is controlled to not exceed 5% of the total formula. The mixture is ground to a fineness of less than 50 μm, and filtered and packaged using a filter to obtain a solvent-free epoxy coating base. C: Mix nanographene and industrial ammonia in a ratio of 1:5, disperse with ultrasound for 2-3 hours, and dehydrate and dry to obtain a modified graphene base material; D: directly adding 0.1-2% of the modified graphene base material to 100% of the solvent-free epoxy coating base material and mixing and stirring to obtain the graphene solvent-free epoxy coating base material; S2: Prepare the finished nano-graphene solvent-free epoxy paint. Before painting, mix the graphene solvent-free epoxy paint base material and the epoxy curing agent in a ratio of 100%:15-25% to obtain the graphene solvent-free epoxy paint. Stir and mature for 20-30 minutes before use. S3: Preparation of nanocomposite particle antifouling topcoat: wherein the nanocomposite particle antifouling topcoat comprises, according to the weight ratio of the formula, 30-50 parts of nano-cuprammonia fiber, 10-30 parts of nano-Power Rock paramagnetic ore, 10-30 parts of nano-graphene, and 30-50 parts of nano-tourmaline. The preparation method comprises the following steps:

1. Prepare nanobubble water, industrial ammonia water, and composite nanoparticles in a ratio of 95:5:1, wherein the nanocomposite nanoparticles have a fineness of <10 nm. The industrial ammonia water is composed of 25-28% NH3·H2O. The nanobubble water uses a nanobubble generator to generate negatively charged nanobubbles of 100 nm. The nanobubble water functions as a surfactant.

2. Processing of composite nanoparticle dispersant: Add nano bubble water and industrial ammonia water into the nano composite nanoparticles 2-4 times, mix and stir for 5-10 minutes to prepare the nano composite particle dispersion.

2. The method for preparing an anti-biofouling coating system according to claim 1, characterized in that: In the first component of step S1, the solvent-free epoxy resin is any one of low molecular weight modified bisphenol A epoxy, low molecular weight modified bisphenol F epoxy, low molecular weight alicyclic epoxy, low molecular weight phenolic modified epoxy resin, or a combination of multiple resins; the wetting dispersant is a solvent-free associative polyurethane or a solvent-free acrylic dispersant; the rust-proof pigment is any one of zinc phosphate, aluminum tripolyphosphate, glass flakes, iron red, and zinc powder, or a combination of multiple resins; the defoamer is an organosilicon defoamer containing hydrophobic ions; the thickener is any one of organic clay, fumed silica, and polyamide thickener; and the nanographene is a two-dimensional structure below 10 nm.

3. The method for preparing an anti-biofouling coating system according to claim 1, characterized in that: In the second component in step S1, the curing agent is any one or more of diethylenetriamine, triethylenetetramine, triethylaminopropylamine, tetraethylenepentamine, menthanediamine, isophoronediamine, diaminodiphenyl sulfone, and diaminodiphenylmethane.

4. The method for preparing an anti-biofouling coating system according to claim 1, characterized in that: In step S2, the weight ratio of the first component to the second component is 100%:15-25%, and the total solid content of the first component and the second component is ≥97%.

5. The method for preparing an anti-biofouling coating system according to claim 1, characterized in that: In step S3, the nanographene is two-dimensional nanographene, and nanographene particles of 2-3 nm are selected. The cuprammonium fiber is non-Li-type cuprammonium fiber, and the nano Power Rock paramagnetic ore is selected from the 2-3 nm level.

6. The use of an anti-biofouling coating system according to claim 1, characterized in that: Applied to the surface of marine vessels, the anti-fouling coating system for preventing biofouling includes a primer and a topcoat, and includes the following application steps: a. Mix the graphene solvent-free epoxy coating base and the curing agent in a ratio of 100%:15-25% and stir evenly to obtain the graphene solvent-free epoxy coating, and ripen it for 20-30 minutes. The coating thickness is 100-200 microns; b: After the primer nano-graphene solvent-free epoxy paint is applied but before the surface is dry, the nano-composite particle anti-fouling topcoat fluid is immediately sprayed with a nano-spray gun for topcoating, implementing the nano-material wet-on-wet coating process.

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