Antibacterial low-surface-energy antifouling paint and application thereof

Abstract

The invention belongs to the technical field of coatings, discloses an antibacterial low-surface-energy antifouling coating and application thereof, and provides an antifouling self-cleaning coating material with high performance and long service life through a chemical bonding antibacterial technology and design of a low-surface-energy fluorosilicone resin and an organosilicon polyurethane composite coating. The coating material disclosed by the invention not only has remarkable antibacterial and antifouling effects, but also overcomes the defects of a traditional coating in the aspects of adhesive force, service life and the like, and provides a new technical path and solution for the fields of ocean engineering, shipbuilding, building outer walls and the like needing efficient antifouling and self-cleaning surfaces.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coatings, and particularly relates to a bacteriostatic low-surface-energy antifouling coating, especially applied to marine equipment. BACKGROUND

[0002] Marine antifouling is related to national major needs such as energy, environment and national defense, and has important strategic significance for the development of marine economy and the maintenance of marine defense safety. Marine environment is complex and harsh, there are various types of fouling organisms, and environmental protection regulations are becoming increasingly stringent. Marine antifouling has always been an international problem, especially static, long-acting and eco-friendly antifouling, which is extremely challenging.

[0003] Antifouling paint is an effective means to solve the problem of fouling of marine equipment. At present, the mainstream products of antifouling paint are tin-free self-polishing antifouling coatings and low-surface-energy antifouling coatings. However, the self-polishing antifouling coating has a short antifouling time, and the release speed of the toxicant is uneven. The low-surface-energy antifouling coating is expensive, the construction is complex, and the static antifouling performance is poor. A certain amount of -CF3 groups are introduced into the side chain of a silicone chain as a main chain, and the groups are oriented on the surface due to their ultra-low surface energy characteristics. The entire macromolecule maintains the high elasticity characteristics of linear polysiloxane, so that it has the characteristics of organic silicon and organic fluorine antifouling coatings. This new type of low-surface-energy antifouling coating based on fluorinated polysiloxane has excellent antifouling performance, and through appropriate structural design and multi-mechanism synergistic effect, the performance of the fluorosilicon coating system can be optimized.

[0004] Environment-friendly and green low-surface-energy coatings represent the research direction of future coatings, and in special military applications such as underwater equipment, only low-surface-energy coatings can be used. Therefore, it is urgent to carry out research on high-end antifouling coating materials for marine biofouling in China. SUMMARY

[0005] In order to solve the above-mentioned problems of marine antifouling coatings, the present application provides a bacteriostatic low-surface-energy antifouling coating and its application. The organic silicon polyurethane composite coating is creatively introduced by scientifically and reasonably introducing a polar polyurethane segment, which not only fundamentally solves the problem of insufficient adhesion of fluorosilicon coating, but also further prolongs the service life of the coating. It provides a new idea and solution for the development of high-performance, long-life antifouling self-cleaning coating materials.

[0006] In order to achieve the purpose of the application, the following technical solutions are provided: The present application provides a bacteriostatic low-surface-energy antifouling coating, which comprises component A and component B. The A component includes the following ingredients in mass percentage: hydroxyl silicone oil 30-50%, bacteriostatic silicone-polyurethane 20-50%, diphenyl diethoxysilane 2-5%, fumed silica 5-20%, iron oxide red 2-10%, talc 0.5-5%, zinc oxide 0.5-1%, kaolin 0.5-1%, leveling agent 0.1-2%, and xylene 10%-30%; The B component includes the following ingredients in mass percentage: quaternary ammonium salt modified silicone curing agent 30-50%, fluorine modified silicone curing agent 10-30%, crosslinking agent 10-20%, and xylene 10%-30%.

[0007] Further, the bacteriostatic silicone-polyurethane includes the following ingredients in weight percentage: hydroxyl-terminated silicone 100 parts, polytetrahydrofuran 20-80 parts, isophorone diisocyanate 10-50 parts, dibutyltin dilaurate 0.1-5 parts, gamma-aminopropyl triethoxysilane 1-5 parts, and coumarin 1-5 parts.

[0008] Further, the preparation method of the bacteriostatic silicone-polyurethane is as follows: The mixture of hydroxyl-terminated silicone and polytetrahydrofuran is added to a reaction container with nitrogen, xylene is used as a solvent, and the reaction is fully stirred under the protection of nitrogen to form a homogeneous solution; Isophorone diisocyanate and dibutyltin dilaurate complex are added dropwise to the homogeneous solution as a polyurethane hard segment and a catalyst, respectively, and the reaction is continuously stirred to obtain a transparent prepolymer solution; An excess amount of gamma-aminopropyl triethoxysilane and coumarin is added to the prepolymer solution, and the reaction is fully carried out to obtain a transparent bacteriostatic silicone-polyurethane.

[0009] Further, the preparation method of the quaternary ammonium salt modified silicone curing agent is as follows: a mixture of N,N-diethyl-3-aminopropyl trimethoxy kuguan and dodecyl bromide is added to a reaction container, acetonitrile is used as a solvent, and the reaction is fully stirred; the obtained solution is rotary evaporated to remove part of the solvent, and the quaternary ammonium salt modified silicone curing agent is obtained.

[0010] Further, the molar ratio of the mixture of N,N-diethyl-3-aminopropyl trimethoxy kuguan and dodecyl bromide is 1:1.

[0011] Further, the preparation method of the fluorine modified silicone curing agent is as follows: three monomers of 1H,1H,2H,2H-perfluorooctyl trimethoxysilane, methyl trimethoxysilane, and dimethyl dimethoxysilane are mixed, water, xylene, and a catalyst are added, and a hydrolysis reaction is carried out to form a homogeneous solution; the obtained homogeneous solution is rotary evaporated to remove the solvent, and the fluorine modified silicone curing agent is obtained.

[0012] Further, the mass ratio of the three monomers of 1H, 1H, 2H, 2H-perfluorooctyltrimethoxysilane, methyltrimethoxysilane and dimethyldimethoxysilane is 0.5:0.5:1.

[0013] Further, the crosslinking agent is any one or a combination of two or more of tetraethyl silicate, methyltrimethoxysilane or tetrabutyl titanate.

[0014] Further, the A component and the B component are mixed in a mass ratio of 5:1.

[0015] The application also provides a use of the bacteriostatic low-surface-energy antifouling coating, which is uniformly stirred, sprayed on the surface of a marine equipment workpiece and cured at room temperature to form a film, thereby obtaining a bacteriostatic low-surface-energy fluorosilicon antifouling film.

[0016] Compared with the prior art, the application has the following beneficial effects: 1. The application breaks through the limitation of traditional antifouling coatings that rely on a single antifouling mechanism, and proposes a multi-mechanism synergistic antifouling method. The antibacterial agent is directly combined into the molecular chain of the fluorosilicon resin by chemical bonding technology, instead of simple physical doping. This chemical bonding method significantly enhances the stability and durability of the antibacterial component, effectively avoids the problem of rapid loss of the antibacterial agent in seawater, and ensures that the antibacterial component can be continuously and stably released, thereby achieving continuous damage to the DNA of bacteria and algae, greatly prolonging the bacteriostatic time and improving the antifouling performance.

[0017] 2. The application fully utilizes the inherent low-surface-energy property (<30 mN / m) of the fluorosilicon resin, which makes it difficult for marine organisms to adhere to the coating surface, forming a first physical antifouling barrier. At the same time, the chemically bonded antibacterial component further prevents the colonization of microorganisms on the coating surface, thereby strengthening the antifouling effect from the biological aspect. The organic combination of physical and biological antifouling mechanisms achieves synergistic scale inhibition, significantly prolonging the antifouling period of the coating.

[0018] 3. The application proposes a silicone polyurethane composite coating design, which effectively enhances the adhesion of the fluorosilicon coating by scientifically and reasonably introducing polar polyurethane segments, thereby fundamentally solving the technical problem of insufficient adhesion of traditional fluorosilicon coatings. This innovative design not only improves the stability and reliability of the coating, but also further prolongs the service life of the coating, providing more reliable protection for practical applications.

[0019] 4. The bacteriostatic low-surface-energy antifouling coating proposed by the application not only has significant bacteriostatic and antifouling effects, but also solves the deficiencies of traditional coatings in adhesion and service life, thereby providing a new technical path and solution for fields that require high-efficiency antifouling self-cleaning surfaces, such as marine engineering, shipbuilding and building exterior walls. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the preparation of antibacterial organic polyurethane. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] Unless otherwise specified, the raw materials used in the following examples were purchased from commercial sources.

[0023] Unless otherwise specified, the methods used in the following examples are all conventional methods in the art.

[0024] Example 1 like Figure 1 As shown, this embodiment provides a method for preparing an antibacterial organosilicon-polyurethane. A mixture of 7.50 g of hydroxyl-terminated organosilicon and 3.75 g of polytetrahydrofuran is added to a three-necked flask filled with nitrogen, with xylene as the solvent, and stirred at 80°C under the protection of nitrogen to form a homogeneous solution. Then, 2.17 g of isophorone diisocyanate and 0.05 g of dibutyltin dilaurate complex are added dropwise to the flask as the polyurethane hard segment and catalyst, respectively, and the mixture is stirred and reacted for 2 hours to obtain a transparent prepolymer solution. Subsequently, 1.10 g of γ-aminopropyltriethoxysilane and 0.05 g of coumarin are added in excess to the remaining ~NCO groups in the polymer and reacted at 80°C for 2 hours to obtain a transparent antibacterial organosilicon-polyurethane.

[0025] This example provides a method for preparing a quaternary ammonium salt-modified organosilicon curing agent: a mixture of 11.77 g of N,N-diethyl-3-aminopropyltrimethoxytetane and 12.462 g of dodecyl bromide was added to a single-necked flask, 40 ml of acetonitrile was used as a solvent, and the mixture was stirred at 85° C. for 24 h. The obtained solution was subjected to a rotary evaporator at 50° C. for 10 min to remove part of the solvent to obtain a quaternary ammonium salt-modified organosilicon curing agent.

[0026] The preparation method of the fluorine-modified silicone curing agent in this embodiment is as follows: 1H, 1H, 2H, 2H-perfluorooctyltrimethoxysilane 10 g, methyltrimethoxysilane 10 g, and dimethyldimethoxysilane 20 g are added into a single-neck flask, water 10 g and xylene 10 g and a catalyst are added, and hydrolysis reaction is carried out at 60°C for 30 min to form a homogeneous solution. The obtained solution is subjected to rotary evaporation at 60°C for 20 min to remove the solvent, and the fluorine-modified silicone curing agent is obtained.

[0027] Example 2 The antibacterial low-surface-energy antifouling coating provided in this embodiment comprises A component and B component, wherein the A component comprises the following components in mass percentage: hydroxyl silicone oil 30%, antibacterial silicone-polyurethane 40%, diphenyldiethoxysilane 5%, fumed silica 5%, red iron oxide 2%, talc powder 5%, zinc oxide 1%, kaolin 1%, leveling agent 1%, and xylene 10%; the B component comprises the following components in mass percentage: quaternary ammonium salt-modified silicone curing agent 30%, fluorine-modified silicone curing agent 30%, crosslinking agent 10%, and xylene 30%. The A component and the B component in this embodiment are mixed in a mass ratio of 5:1, and after mixing, stirring is uniformly carried out. After spraying on the surface of a workpiece, room temperature curing is carried out to form a film, and a workpiece sample with an antibacterial low-surface-energy fluorosilicon antifouling film is obtained.

[0028] Example 3 The antibacterial low-surface-energy antifouling coating provided in this embodiment comprises A component and B component, wherein the A component comprises the following components in mass percentage: hydroxyl silicone oil 35%, antibacterial silicone-polyurethane 20%, diphenyldiethoxysilane 2%, fumed silica 20%, red iron oxide 10%, talc powder 1%, zinc oxide 0.5%, kaolin 0.5%, leveling agent 1%, and xylene 10%; the B component comprises the following components in mass percentage: quaternary ammonium salt-modified silicone curing agent 35%, fluorine-modified silicone curing agent 25%, crosslinking agent 15%, and xylene 25%. The A component and the B component in this embodiment are mixed in a mass ratio of 5:1, and after mixing, stirring is uniformly carried out. After spraying on the surface of a workpiece, room temperature curing is carried out to form a film, and a workpiece sample with an antibacterial low-surface-energy fluorosilicon antifouling film is obtained.

[0029] Example 4 The embodiment provides a bacteriostatic low-surface-energy antifouling paint, which comprises an A component and a B component, wherein the A component comprises the following components in percentage by mass: 50% of hydroxyl silicone oil, 20% of bacteriostatic organic silicon-polyurethane, 2% of diphenyldiethoxysilane, 6% of fumed silica, 2.5% of red iron oxide, 1% of talcum powder, 0.5% of zinc oxide, 0.5% of kaolin, 0.5% of a leveling agent and 17% of dimethylbenzene; and the B component comprises the following components in percentage by mass: 50% of a quaternary ammonium salt modified organic silicon curing agent, 10% of a fluorine modified organic silicon curing agent, 30% of a crosslinking agent and 10% of dimethylbenzene. The A component and the B component in the embodiment are mixed in a mass ratio of 5:1, are uniformly stirred after mixing, are sprayed on the surface of a workpiece, are cured at room temperature to form a film, and a workpiece sample with a bacteriostatic low-surface-energy fluorosilicon antifouling film is obtained.

[0030] Embodiment 5 The embodiment provides a bacteriostatic low-surface-energy antifouling paint, which comprises an A component and a B component, wherein the A component comprises the following components in percentage by mass: 30% of hydroxyl silicone oil, 49% of bacteriostatic organic silicon-polyurethane, 2% of diphenyldiethoxysilane, 5% of fumed silica, 2% of red iron oxide, 0.5% of talcum powder, 0.5% of zinc oxide, 0.5% of kaolin, 0.5% of a leveling agent and 10% of dimethylbenzene; and the B component comprises the following components in percentage by mass: 40% of a quaternary ammonium salt modified organic silicon curing agent, 20% of a fluorine modified organic silicon curing agent, 15% of a crosslinking agent and 25% of dimethylbenzene. The A component and the B component in the embodiment are mixed in a mass ratio of 5:1, are uniformly stirred after mixing, are sprayed on the surface of a workpiece, are cured at room temperature to form a film, and a workpiece sample with a bacteriostatic low-surface-energy fluorosilicon antifouling film is obtained.

[0031] The workpiece samples prepared in Embodiments 2-5 are subjected to a six-month real sea coupon antifouling experiment, and Table 1 is obtained.

[0032] Table 1

[0033] The above merely provides the embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process conversion according to the content of the present application, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An antibacterial low surface energy antifouling coating, characterized in that: The antifouling coating comprises component A and component B; Component A includes the following ingredients in percentage by mass: 30-50% hydroxy silicone oil, 20-50% antibacterial silicone-polyurethane, 2-5% diphenyldiethoxysilane, 5-20% fumed silica, 2-10% red iron oxide, 0.5-5% talc, 0.5-1% zinc oxide, 0.5-1% kaolin, 0.1-2% leveling agent and 10%-30% xylene; Component B includes the following ingredients in percentage by mass: 30-50% of quaternary ammonium salt modified organic silicon curing agent, 10-30% of fluorine modified organic silicon curing agent, 10-20% of crosslinking agent and 10%-30% of xylene.

2. The antibacterial low surface energy antifouling coating according to claim 1, characterized in that: The antibacterial silicone-polyurethane comprises the following components in parts by weight: 100 parts of hydroxyl-terminated silicone, 20-80 parts of polytetrahydrofuran, 10-50 parts of isophorone diisocyanate, 0.1-5 parts of dibutyltin dilaurate, 1-5 parts of gamma-aminopropyltriethoxysilane and 1-5 parts of coumarin.

3. The antibacterial low surface energy antifouling coating according to claim 2, characterized in that: The preparation method of the antibacterial silicone-polyurethane is as follows: A mixture of hydroxyl-terminated organosilicon and polytetrahydrofuran is added to a reaction vessel filled with nitrogen, and xylene is used as a solvent. Under the protection of nitrogen, the mixture is stirred and reacted to form a homogeneous solution; Isophorone diisocyanate and dibutyltin dilaurate complex, as polyurethane hard segment and catalyst respectively, were added dropwise to the homogeneous solution and stirred to react to obtain a transparent prepolymer solution. An excess of γ-aminopropyltriethoxysilane and coumarin are added to the prepolymer solution and fully reacted to obtain a transparent antibacterial silicone-polyurethane.

4. The antibacterial low surface energy antifouling coating according to claim 1, characterized in that: The preparation method of the quaternary ammonium salt modified organic silicon curing agent comprises the following steps: adding a mixture of N,N-diethyl-3-aminopropyltrimethoxytidine and dodecyl bromide into a reaction vessel, using acetonitrile as a solvent, and fully stirring the reaction; and using a rotary evaporator to evaporate the obtained solution to remove part of the solvent, thereby obtaining the quaternary ammonium salt modified organic silicon curing agent.

5. The antibacterial low surface energy antifouling coating according to claim 4, characterized in that: The molar ratio of the mixture of N,N-diethyl-3-aminopropyltrimethoxytridene and dodecyl bromide is 1:

1.

6. The antibacterial low surface energy antifouling coating according to claim 1, characterized in that: The preparation method of the fluorine-modified organic silicon curing agent comprises: mixing three monomers, 1H,1H,2H,2H-perfluorooctyltrimethoxysilane, methyltrimethoxysilane and dimethyldimethoxysilane, adding water, xylene and a catalyst, and performing a hydrolysis reaction to form a homogeneous solution; the obtained homogeneous solution is rotary evaporated using a rotary evaporator to remove the solvent, thereby obtaining the fluorine-modified organic silicon curing agent.

7. The antibacterial low surface energy antifouling coating according to claim 6, characterized in that: The mass ratio of the three monomers, 1H,1H,2H,2H-perfluorooctyltrimethoxysilane, methyltrimethoxysilane and dimethyldimethoxysilane, is 0.5:0.5:

1.

8. The antibacterial low surface energy antifouling coating according to claim 1, characterized in that: The crosslinking agent is any one of tetraethyl silicate, methyltrimethoxysilane or tetrabutyl titanate, or a combination of two or more thereof.

9. The antibacterial low surface energy antifouling coating according to any one of claims 1 to 8, characterized in that: The component A and the component B are mixed in a mass ratio of 5:

1.

10. An application of an antibacterial low surface energy antifouling coating, characterized by: The antibacterial low surface energy antifouling coating according to claim 1 is stirred evenly, sprayed on the surface of a workpiece of marine engineering equipment, and then cured at room temperature to form a film, thereby obtaining an antibacterial low surface energy fluorosilicone antifouling film.

Images