Marine antifouling coating with piezoelectric conductive performance and preparation and application thereof

Abstract

The application discloses a marine antifouling coating with piezoelectric conductive performance and preparation and application thereof, which comprises the following components in mass fraction: 45-80 parts of film-forming resin, 5-55 parts of zinc oxide particles, 5-30 parts of a conductive agent, 0.1-1.0 parts of an additive, 10-20 parts of an organic solvent and 10-25 parts of a curing agent. The coating of the application can generate current voltage under the pressure of changing seawater, the current voltage is released on the surface of the coating, electrochemical reaction is generated with seawater, an ultraoxidation film composed of superoxide radical ions, free hydroxyl radicals and hypochlorite ions is formed on the surface of the coating, and the spores and microorganisms of fouling organisms attached to the surface are killed, so that the marine organisms are prevented from adhering, and long-acting antifouling can be realized.

Description

Technical Field

[0001] This invention relates to the field of marine antifouling coating technology, and in particular to a marine antifouling coating with piezoelectric conductivity and its preparation and application. Background Technology

[0002] Existing methods for preventing marine biofouling mainly include antifouling coatings, electrolytic antifouling, ultrasonic technology, self-polishing resin release of toxic substances, and physical removal. Among these, antifouling coatings and electrochemical antifouling are the two most mature methods and have been widely used in ships, marine engineering equipment, and seawater pipelines.

[0003] Electrochemical antifouling primarily relies on electrolytic antifouling, which mainly comprises three types of systems: first, seawater electrolysis to produce chlorine; second, Cu-m (Fe, Al, etc.) anodic antifouling systems; and third, Cu-Cl2 antifouling systems. Its key drawbacks are the need for specialized seawater electrolysis antifouling equipment, high power consumption, and the requirement to transport the antifouling products generated during electrolysis to the surface of the material requiring antifouling, limiting its applicability to only certain seawater pipeline systems. Furthermore, most of these are anodic consumable fouling control technologies with limited lifespans, and the generated copper ions can pollute the environment.

[0004] Therefore, there is a need for a marine antifouling solution that can achieve long-lasting antifouling without the need for an external power source and is applicable to a wide range of equipment. Summary of the Invention

[0005] In view of this, this application provides a marine antifouling coating with piezoelectric conductivity, its preparation and application, to solve the problem of how to achieve long-term antifouling of marine equipment under conditions without power.

[0006] To achieve the above technical objectives, this application adopts the following technical solution:

[0007] In a first aspect, this application provides a marine antifouling coating with piezoelectric conductivity, comprising the following components in parts by weight: 45-80 parts film-forming resin, 5-55 parts zinc oxide particles, 5-30 parts conductive agent, 0.1-1.0 parts additives, 10-20 parts organic solvent, and 10-25 parts curing agent.

[0008] Preferably, the zinc oxide particles are monocrystalline zinc oxide particles.

[0009] Preferably, the film-forming resin includes organic resin and urushiol resin, and the organic resin includes one or more of fluorocarbon resin, fluoropropylene resin, epoxy resin, polyurethane resin, silicone acrylic resin, styrene acrylic resin, and pure acrylic resin.

[0010] Preferably, the mass of urushiol resin is 1-3% of the total mass of film-forming resin.

[0011] Preferably, the conductive agent includes one or more of the following: gold powder, silver powder, copper powder, zinc powder, iron powder, aluminum powder, manganese powder, conductive graphite powder, and conductive carbon nanotubes.

[0012] Preferably, the mass ratio of zinc oxide to conductive agent is 1-10:1.

[0013] Preferably, the average particle size of the conductive agent is 0.2 μm-50 μm.

[0014] Secondly, this application provides a method for preparing a marine antifouling coating with piezoelectric conductivity, comprising the following steps:

[0015] S1. Mix the film-forming resin, solvent, zinc oxide powder, and additives, disperse them ultrasonically, grind them evenly, add the conductive agent, disperse them ultrasonically, and obtain a mixture.

[0016] S2. After mixing the mixture with the curing agent, adjust the viscosity to obtain a marine antifouling coating with piezoelectric conductivity.

[0017] Thirdly, this application provides a method for using a marine antifouling coating with piezoelectric conductivity, wherein the marine antifouling coating is sprayed onto the surface of the biocontaminated area of ​​marine equipment, and after curing, the marine equipment with the coating is formed. The marine equipment with the coating is placed in flowing seawater, that is, a superoxide film is formed on the surface of the coating; the biocontaminated area includes the splash area and / or the underwater part.

[0018] Fourthly, this application provides the application of a marine antifouling coating with piezoelectric conductivity in the treatment of marine biological pollution.

[0019] The beneficial effects of this application are as follows: The piezoelectric conductive antifouling coating of the present invention does not require an external power source. Under the changing pressure of seawater, the piezoelectric material (zinc oxide crystal) of the coating of this application generates current and voltage. The current and voltage are released on the surface of the coating and produce an electrochemical reaction with seawater, forming a superoxide film on the surface of the coating composed of superoxide ions, free hydroxyl groups, hypochlorite ions, etc., which kills the fouling spores and microorganisms attached to the surface, prevents marine organisms from attaching, and can achieve long-term antifouling effect.

[0020] The product of this invention can be industrialized, has good piezoelectricity, adjustable conductivity, simple preparation method, low cost, is non-toxic and environmentally friendly, and has a wide range of applications in marine equipment. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] This application provides a marine antifouling coating with piezoelectric conductivity, comprising the following components in parts by weight: 45-80 parts film-forming resin, 5-55 parts zinc oxide particles, 5-30 parts conductive agent, 0.1-1.0 parts additives, 10-20 parts organic solvent, and 10-25 parts curing agent.

[0023] The principle of the marine antifouling coating with piezoelectric conductivity of this application for preventing fouling of marine equipment is as follows: when the piezoelectric conductive coating is subjected to seawater pressure changes on the equipment surface, a micro-current voltage is generated, so that the current voltage change of the potential on the equipment surface is dynamically balanced. The electrochemical reaction between the micro-current voltage and seawater forms a superoxide film on the equipment surface, thereby inhibiting the adhesion of microorganisms on the equipment surface and preventing further biofouling.

[0024] In some embodiments, the additives include one or more of defoamers, anti-settling agents, wetting agents, leveling agents, and drying agents. The function of defoamers is to prevent the formation of bubbles in the coating solution. The function of anti-settling agents is to prevent fillers from settling too quickly, leading to uneven distribution of fillers in the coating. The function of wetting agents is to ensure sufficient contact between the coating and the substrate interface, enhancing adhesion. The function of leveling agents is to reduce sagging and create a smooth coating. The function of drying agents is to promote the redox reaction of the coating, accelerating its drying process.

[0025] In some embodiments, the curing agent includes one or more of ethylenediamine, diethylenetriamine, m-phenylenediamine, m-phenylenediamine, isocyanate, polyamide, and amine addition curing agents.

[0026] In some embodiments, the organic solvent is a mixture of xylene and n-butanol in a mass ratio of 7:3, which can be used to adjust the viscosity of coatings and disperse various materials.

[0027] The film-forming resin of this application serves to improve the adhesion of marine antifouling coatings and has good film-forming properties, including but not limited to one or more of fluorocarbon resin, fluoropropylene resin, epoxy resin, polyurethane resin, silicone acrylic resin, styrene acrylic resin, and pure acrylic resin.

[0028] In some embodiments, the film-forming resin comprises an organic resin and an urushiol resin. The mass of the urushiol resin is 1-3% of the total mass of the film-forming resin.

[0029] The purpose of adding urushiol resin to film-forming resin is to improve the bactericidal and seawater corrosion resistance of film-forming resin through blending modification. At the same time, urushiol resin is a high molecular weight substance, and its compatibility is better than that of systems with added small molecules. The modification does not have a significant impact on the other properties of the original organic resin.

[0030] In some embodiments, the zinc oxide particles are monocrystalline zinc oxide particles. Monocrystalline zinc oxide particles are beneficial for piezoelectric enhancement, further improving the sensitivity of antifouling performance.

[0031] The preparation method of single-crystal zinc oxide particles is as follows: A cleaned substrate is placed in a reaction chamber; the Roots pump and the forepump are turned on, and the sample pan, carrier gas channel, and chamber wall are heated while a vacuum is being drawn, with carrier gas being blown during the heating process; when the temperature of the chamber wall reaches a first predetermined temperature, the carrier gas is turned off and the molecular pump is turned on; when the temperature of the chamber wall reaches a second predetermined temperature, the molecular pump is turned off and the carrier gas is turned on; wherein the second predetermined temperature is higher than the first predetermined temperature, when the temperature of the sample pan changes within the first temperature range, and the temperature of the carrier gas channel and the chamber wall changes within the second temperature range, the subsequent deposition process begins, achieving a good technical effect in preparing single-crystal zinc oxide thin films. The sample pan temperature is set to 200℃, and the carrier gas channel and chamber wall temperatures are set to 100℃. Alternatively, the sample pan temperature is set to 200℃, the carrier gas channel temperature to 110℃, and the chamber wall temperature to 100℃. The single-crystal zinc oxide film is scraped off to obtain single-crystal zinc oxide powder, which is then sieved through an 800-mesh sieve for later use.

[0032] Conductive agents include one or more of the following: gold powder, silver powder, copper powder, zinc powder, iron powder, aluminum powder, manganese powder, conductive graphite powder, and conductive carbon nanotubes. The conductive agents, uniformly distributed in the coating resin, and the piezoelectric material (zinc oxide crystals) work together to achieve piezoelectric antifouling properties. Under varying seawater pressure, the zinc oxide crystals generate a current and voltage, which are released through the conductive agent onto the coating surface, reacting electrochemically with the seawater to form a superoxide film on the coating surface. This film kills fouling spores and microorganisms attached to the surface, preventing marine organisms from adhering and achieving long-lasting antifouling.

[0033] In some embodiments, the mass ratio of zinc oxide to conductive agent is 1-10:1. The total amount of zinc oxide and conductive agent is constant; if the proportion of zinc oxide is too high, the conductivity will be insufficient, resulting in a lack of antifouling performance. If the proportion of zinc oxide is too low, the generated electricity will be insufficient, also resulting in a lack of antifouling performance.

[0034] In some embodiments, the average particle size of the conductive agent is 0.2 μm-50 μm. If the particle size is too small, conductivity is lost; if the particle size is too large, it hinders the generation of electricity by the piezoelectric material.

[0035] This application provides a method for preparing a marine antifouling coating with piezoelectric conductivity, comprising the following steps:

[0036] S1. Mix the film-forming resin, solvent, zinc oxide powder, and additives, disperse them ultrasonically, grind them evenly, add the conductive agent, disperse them ultrasonically, and obtain a mixture.

[0037] S2. After mixing the mixture with the curing agent, adjust the viscosity to obtain a marine antifouling coating with piezoelectric conductivity.

[0038] In step S1, since the conductive agent is metal powder, if the metal powder participates in the grinding, it is easy to cause a violent oxidation-reduction reaction and an explosion. Therefore, post-treatment is performed.

[0039] In step S2, the coating method involves spraying through a spray gun or disc atomizer, using high-pressure air pressure to disperse the material into uniform and fine droplets, and applying it to the surface of the object. In some embodiments, gravity compressed air spray guns are used for spraying, including but not limited to one or more of the following: high-flow-rate low-pressure atomization spraying, thermal spraying, automatic spraying, and multi-group spraying.

[0040] This application provides a method for using a marine antifouling coating with piezoelectric conductivity. The marine antifouling coating is sprayed onto the surface of the biocontaminated area of ​​marine equipment. After curing, the marine equipment with the coating is formed. The marine equipment with the coating is placed in flowing seawater, which forms an oxide film on the surface of the coating. The biocontaminated area includes the splash area and / or the underwater part.

[0041] Marine equipment includes, but is not limited to, ships, drilling platforms, deep-sea cages, and vessels; it can prevent and control biological pollution of marine equipment, reduce the harm of biological pollution, improve the safety and efficiency of equipment use, extend the life cycle of equipment, and has a wide range of applications.

[0042] After the piezoelectric conductive coating of this application is applied to the surface of the equipment, the microcurrent voltage generated under the changing seawater pressure reacts with the seawater electrochemically to form an electrochemical antifouling system. The electrochemical reaction products on the surface form a superoxide film composed of superoxide ions, free hydroxyl groups, hypochlorite ions, etc., which kills the fouling spores and microorganisms attached to the surface and prevents marine organisms from attaching.

[0043] Fourthly, this application provides the application of a marine antifouling coating with piezoelectric conductivity in the treatment of marine biological pollution.

[0044] The piezoelectric and conductive marine antifouling coating of this invention endows the coating with excellent piezoelectric and conductive properties. When marine equipment operates in the ocean, due to mechanical pressure, the piezoelectric and conductive antifouling coating outputs current and voltage, converting mechanical energy into electrical energy with high efficiency. The generated current and voltage undergo an electrochemical reaction with seawater, forming a superoxide film on the coating surface composed of hypochlorite ions, free hydroxyl groups, and negative oxygen ions. This film continuously kills surface microorganisms and spores, thereby preventing biofouling. This achieves the technical effect of effectively removing organic or inorganic contaminants that may adhere to the substrate surface.

[0045] The following specific embodiments further illustrate this solution.

[0046] Example 1

[0047] A marine antifouling coating with piezoelectric conductivity comprises the following components in parts by weight: 52 parts film-forming resin, 36 parts monocrystalline zinc oxide particles, 12 parts flaky zinc powder with a size of 10 μm, 0.5 parts defoamer, 0.1 parts leveling agent, 0.2 parts wetting agent, 0.3 parts anti-settling agent, 10 parts organic solvent, and 10 parts curing agent; the film-forming resin is E44 epoxy resin and urushiol resin; the mass of urushiol resin is 1.5% of the total mass of the film-forming resin; the organic solvent is a mixture of xylene and n-butanol in a mass ratio of 7:3; and the curing agent is a mixture of m-phenylenediamine and isocyanate in a mass ratio of 3:1.

[0048] A method for preparing a marine antifouling coating with piezoelectric conductivity includes the following steps:

[0049] S1. Weigh 100g of zinc oxide particles with a purity of 99.5% or higher, grind them and sieve them through an 800-mesh sieve to obtain zinc oxide powder for later use. Mix the film-forming resin, solvent, zinc oxide powder and additives by stirring for 3 hours, then ultrasonically disperse them, grind them evenly, and then add a conductive agent and ultrasonically disperse them to obtain a mixture.

[0050] S2. After mixing the mixture with the curing agent, adjust the viscosity to 80 mPa·s with an organic solvent (7:3 xylene and n-butanol) to obtain a marine antifouling coating with piezoelectric conductivity.

[0051] Examples 2-4

[0052] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that the amount of single-crystal zinc oxide particles used is 10 parts, 20 parts, and 55 parts, respectively.

[0053] Examples 5-6

[0054] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that the amount of conductive agent used is 5 parts and 20 parts, respectively.

[0055] Examples 7-9

[0056] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that the particle size of the conductive agent is 200 nm, 100 nm, and 50 μm.

[0057] Example 10

[0058] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that the single-crystal zinc oxide particles are replaced with zinc oxide particles (Banana Brand Henan Hengyu Chemical Products Co., Ltd.).

[0059] Example 11

[0060] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that the film-forming resin is E44 epoxy resin.

[0061] Comparative Examples 1-2

[0062] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that the amount of single-crystal zinc oxide particles used is 1 part and 110 parts, respectively.

[0063] Comparative Example 3

[0064] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that it does not include single-crystal zinc oxide particles and the amount of conductive agent is 40 parts.

[0065] Comparative Example 4

[0066] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that it does not include a conductive agent and the amount of single-crystal zinc oxide particles is 40 parts.

[0067] Comparative Examples 5-6

[0068] A marine antifouling coating with piezoelectric conductivity is the same as in Example 1, except that the particle sizes of the conductive agents are 100 nm and 60 μm, respectively.

[0069] Testing and Evaluation

[0070] The marine antifouling coatings used in the examples and comparative examples were sprayed onto the surface of a 300×100×3mm epoxy resin board in the biocontaminated area. After curing, a 300×100×3mm epoxy resin board with a coating was formed. Holes were drilled at the four corners of the coated 300×100×3mm epoxy resin board, and it was fixed to an iron frame with screws. The entire board was placed in seawater at a depth of 1.5-2.5m, and the microbial attachment was observed after 60 days. The humidity of the spraying environment was kept below 50%, the surface drying time was 2 hours, and the full drying time was 24 hours.

[0071] The test results are shown in Table 1.

[0072] Table 1 Results of marine organism attachment

[0073]

[0074] As shown in Table 1, an excessively high zinc oxide ratio results in insufficient conductivity and a lack of antifouling performance. An excessively low zinc oxide ratio leads to insufficient electricity generation and a lack of antifouling performance. Both excessively small and excessively large conductive agent particle sizes are detrimental to the antifouling effect. Using either a conductive agent or zinc oxide alone provides virtually no antifouling performance.

[0075] The above results demonstrate that the piezoelectric conductive antifouling coating of the present invention does not require an external power source. Under varying seawater pressure, the piezoelectric material (zinc oxide crystal) of the coating generates current and voltage, which is released on the coating surface and reacts electrochemically with seawater to form a superoxide film on the coating surface composed of superoxide ions, free hydroxyl groups, hypochlorite ions, etc. This film kills fouling spores and microorganisms attached to the surface, prevents marine organisms from attaching, and achieves long-lasting antifouling.

[0076] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for applying a marine antifouling coating with piezoelectric conductivity, characterized in that, The marine antifouling coating is sprayed onto the surface of the biocontaminated area of ​​marine equipment. After curing, the coated marine equipment is formed. The coated marine equipment is then placed in flowing seawater, whereby a superoxide film is formed on the coating surface. The biocontaminated area includes the splash zone and / or the underwater portion. The marine antifouling coating is composed of the following components in parts by weight: 45-80 parts film-forming resin, 5-55 parts zinc oxide particles, 5-30 parts conductive agent, 0.1-1.0 parts additives, 10-20 parts organic solvent, and 10-25 parts curing agent. The zinc oxide particles are monocrystalline zinc oxide particles. The conductive agent and monocrystalline zinc oxide particles are uniformly distributed in the coating resin. The average particle size of the conductive agent is 0.2 μm-50 μm.

2. The method of using the marine antifouling coating with piezoelectric conductivity according to claim 1, characterized in that, The film-forming resin includes organic resin and urushiol resin. The organic resin includes one or more of fluorocarbon resin, fluoropropylene resin, epoxy resin, polyurethane resin, silicone acrylic resin, styrene acrylic resin, and pure acrylic resin.

3. The method of using the marine antifouling coating with piezoelectric conductivity according to claim 2, characterized in that, The mass of the urushiol resin is 1-3% of the total mass of the film-forming resin.

4. The method of using the marine antifouling coating with piezoelectric conductivity according to claim 1, characterized in that, The conductive agent includes one or more of the following: gold powder, silver powder, copper powder, zinc powder, iron powder, aluminum powder, manganese powder, conductive graphite powder, and conductive carbon nanotubes.

5. The method of using the marine antifouling coating with piezoelectric conductivity according to claim 1, characterized in that, The mass ratio of the zinc oxide particles to the conductive agent is 1-10:

1.

6. The method of using the marine antifouling coating with piezoelectric conductivity according to any one of claims 1-5, characterized in that, The preparation method of the marine antifouling coating includes the following steps: S1. Mix the film-forming resin, organic solvent, zinc oxide particles, and additives, then disperse them ultrasonically, grind them evenly, add the conductive agent, disperse them ultrasonically again, and obtain a mixture. S2. After mixing the mixture with the curing agent, adjust the viscosity to obtain the marine antifouling coating with piezoelectric conductivity.

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