Photocuring transparent antifouling coating as well as preparation method and application thereof

Abstract

The invention discloses a light-cured transparent antifouling coating as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, preparing light-curable functional silicon resin; s2, carrying out a reaction on a diisocyanate monomer and polyol to prepare a polyurethane prepolymer with the end capped by an isocyanate group; s3, mixing the isocyanate group terminated polyurethane prepolymer, a methacrylic acid hydroxyl monomer and a polymerization inhibitor, and carrying out a reaction to prepare a methacrylic acid group terminated polyurethane prepolymer; s4, mixing and stirring functional silicon resin, the methacrylic acid hydroxyl monomer-terminated polyurethane prepolymer, a methacrylic acid hydrophilic monomer and a methacrylic acid hydrophobic monomer, and performing ultrasonic oscillation to obtain a resin solution; s5, adding a photoinitiator into the resin solution, and performing ultrasonic oscillation to obtain antifouling resin; and S6, coating the antifouling resin on the surface of the base material, and curing. The antifouling coating prepared by the invention has good antibacterial and diatom adhesion inhibition performance.

Description

Technical Field

[0001] The present invention relates to the field of marine antifouling coatings, and in particular to a photocurable transparent antifouling coating and a preparation method and application thereof. Background Art

[0002] Marine resources are an important part of national resources, and the ability to develop and utilize marine resources is also a manifestation of a country's comprehensive national strength. At present, in the process of developing marine resources, the problems of reduced collection efficiency and reduced transmission efficiency caused by the attachment of marine fouling to the visual windows of detection equipment, marine photovoltaic equipment, and underwater sensor surfaces have restricted the development and utilization of marine resources. Therefore, it is necessary to develop a surface protective transparent antifouling coating technology for underwater transparent equipment with a simple preparation method and good antifouling effect.

[0003] However, the currently used technologies mostly use the method of continuously peeling off or releasing toxic molecules and polymer materials into the water to achieve the antifouling effect. The continuously released substances may harm the ecological environment and life and health, so it is necessary to develop an antifouling coating based on interface characteristics. Furthermore, the curing method of the current antifouling coating mostly adopts high-temperature curing, and its applicability is subject to certain limitations. Therefore, the present invention develops a photocurable transparent interface antifouling coating, which has the characteristics of room temperature photocuring and high optical transparency, and can be used for the protection of underwater high-transparency equipment.

[0004] Xiang Hongping et al. used epoxy-modified silicone resin A, epoxy-modified silicone resin B and sulfide in Chinese patent CN117363215A, "A photocurable paint, coating and its application", to prepare a long-lasting antibacterial coating with good mechanical properties and excellent corrosion resistance.

[0005] Chen Bo et al., in their Chinese patent CN117777822A, "A method for preparing a hydrophilic antibacterial and mildew-proof photocuring coating", used tannic acid, long-chain quaternary ammonium salts and zinc chloride as main raw materials to produce a coating with excellent hydrophilic properties and long-lasting antibacterial and mildew-proof properties.

[0006] Sun Guanqing et al., in Chinese patent CN116179059A, "A transparent photocurable coating and its preparation method", combined filler dispersion technology with photocuring technology to prepare a photocurable coating with good substrate adhesion, hardness, wear resistance and transparency.

[0007] The photocurable coatings prepared by the above method are applicable, but the performance of each coating in inhibiting the adhesion of marine fouling needs further investigation and verification. Summary of the invention

[0008] In view of this, in view of the urgent need for transparent coating preparation and application technology in the field of marine antifouling, and to solve the problem that underwater visual equipment and detection equipment are easily affected by fouling during the development of marine resources, the purpose of the present invention is to propose a photocurable transparent antifouling coating and its preparation method and application, which has good antibacterial and diatom adhesion inhibition properties.

[0009] The technical solutions adopted are:

[0010] A method for preparing a light-cured transparent antifouling coating of the present invention comprises the following steps:

[0011] S1. Preparation of functional silicone resin: reacting tetraethyl orthosilicate, a photoinitiator siloxane monomer and a functional siloxane monomer in a sol-gel system, and then removing the solvent to prepare a photocurable functional silicone resin;

[0012] S2. reacting a diisocyanate monomer with a polyol to prepare an isocyanate group-terminated polyurethane prepolymer;

[0013] S3. The isocyanate group-terminated polyurethane prepolymer, the methacrylic acid hydroxyl monomer and the polymerization inhibitor are mixed and reacted to prepare a methacrylic acid group-terminated polyurethane prepolymer;

[0014] S4. Resin preparation: functional silicone resin, polyurethane prepolymer terminated with methacrylic acid hydroxyl monomer, methacrylic acid hydrophilic monomer and methacrylic acid hydrophobic monomer are mixed and stirred and ultrasonically vibrated to obtain a resin solution;

[0015] S5. The photoinitiator is added to the resin solution obtained in S4, and ultrasonic oscillation is performed to obtain an antifouling resin;

[0016] S6. Apply the antifouling resin to the surface of the substrate and cure it to form a completely cured transparent antifouling coating.

[0017] Further, in step S1, the photoinitiated siloxane monomer includes one or more of 3-(isomethacryloyloxy)propyl trimethoxysiloxane, vinyl trimethoxysiloxane, acryloxypropyl trimethoxysiloxane, acrylamidopropyl trimethoxysiloxane, methacryloxymethyl trimethoxysiloxane, 3-(N-allylamino)propyl trimethoxysiloxane, and acetoxypropyl trimethoxysiloxane;

[0018] The functional siloxane monomer includes one or more of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, pentafluorophenylpropyltrimethoxysiloxane, 2-(2-pyridyl)ethyltrimethoxysiloxane, and tetramethylguanidinylpropyltrimethoxysiloxane.

[0019] Furthermore, in step S1, the mass ratio of tetraethyl orthosilicate, photoinitiated siloxane monomer and functional siloxane monomer is 1:(0.1-1):(0.3-1.2).

[0020] Furthermore, in step S2, the diisocyanate monomer includes one or more of isophorone diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate; the polyol includes one or more of polyethylene glycol, polypropylene glycol, and polytetrahydrofuran; and the mass ratio of the diisocyanate monomer to the polyol is 1:(0.6-1).

[0021] Furthermore, in step S3, the hydroxyl methacrylate monomer includes one or both of hydroxyethyl methacrylate and hydroxypropyl methacrylate; and the mass ratio of the polyurethane prepolymer to the hydroxyl methacrylate monomer is 1:(0.2-0.5).

[0022] Furthermore, in step S4, the mass ratio of the functional silicone resin to the polyurethane prepolymer terminated with the methacrylic acid hydroxyl monomer, the methacrylic acid hydrophilic monomer and the methacrylic acid hydrophobic monomer is: 1: (0.05-0.5): (0.1-0.5): (0.1-0.5).

[0023] Further, in step S5, the photoinitiator includes one or more of benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and hydroxycyclohexane phenone.

[0024] Further, in step S6, the substrate includes one or more of a steel sheet, a glass, a polymethacrylate sheet, a polycarbonate sheet, a polyethylene terephthalate sheet and a wood sheet; and / or the coating method is one of brushing, spin coating, scraping and dipping.

[0025] Furthermore, in step S6, the curing time is 5-120 minutes.

[0026] The photocurable transparent antifouling coating of the present invention is prepared by the preparation method described in any one of the above schemes.

[0027] The above-mentioned photocurable transparent antifouling coating is used for surface protection of equipment and facilities including marine photovoltaic equipment, underwater detection instruments, underwater sensors, underwater vehicles and visual windows.

[0028] In the above technical solution,

[0029] Technical description of step S1: The present invention uses the silanol groups after hydrolysis of tetraethyl orthosilicate as the cross-linking sites of silicone resin, introduces photo-initiated siloxane monomers as the cross-linking sites of the photocuring process, and the functional siloxane monomers can give the material hydrophobic and antibacterial properties. In the sol-gel system, the ester bonds in tetraethyl orthosilicate and siloxane monomers are hydrolyzed to produce silanol groups, which are dehydrated and condensed to form a cross-linked silicon-based resin network with a photo-initiated structure and a functional structure.

[0030] Technical description of step S2: The isocyanate group with higher activity in the isocyanate undergoes an addition reaction with the nucleophilic center in the hydroxyl group. That is, the nucleophilic center in the hydroxyl group attacks the carbon atom in the isocyanate group, and the proton is transferred from the nitrogen atom to form a carbamate structure. This step prepares a polyurethane prepolymer terminated with an isocyanate group.

[0031] Technical description of step S3: A polyurethane prepolymer terminated with a methacrylic acid group is prepared by reacting the hydroxyl group in the methacrylic acid hydroxyl monomer with the remaining isocyanate group in step S2.

[0032] Technical description of step S4: The functional silicone resin is fully mixed with other methacrylic acid monomers, and ultrasonic oscillation is used to achieve uniform dispersion of the raw materials.

[0033] Technical description of step S5: Add the photoinitiator to the resin dispersed in step 4, and evenly disperse the initiator in the resin by ultrasonic oscillation to obtain the antifouling resin.

[0034] Technical description of step S6: UV initiation is to use the energy of light to induce the electrons in the photoinitiator monomer molecules to transition to an excited state, forming active free radicals, which further react with other monomer molecules to gradually form a high molecular polymer. The photoinitiator siloxane monomer serves as a cross-linking site, with one end located in the main structure of the silicone resin and the other end located in the methacrylate polymer structure.

[0035] The antifouling coating prepared by the above-mentioned preparation method can be applied to the surface protection of equipment such as visual windows of underwater vehicles, marine photovoltaic equipment and underwater sensors.

[0036] The photocurable marine antifouling coating with high optical transparency prepared by the present invention uses tetraethyl orthosilicate as the crosslinking site of silicone resin material, uses quaternary ammonium salt and other groups as antibacterial functional monomers, uses photo-initiated 3-(isobutyleneoxy)propyltrimethoxysiloxane as the crosslinking site of silicone resin and methacrylate resin, improves the mechanical properties of the coating by introducing a polyurethane structure, and the amphiphilic groups of the methacrylate resin achieve efficient antifouling. In the process, ultraviolet-induced photocuring reaction is used as a coating preparation method, thereby achieving convenient and efficient coating preparation.

[0037] The antifouling coating prepared by the present invention has dual antifouling performance: 1) structures such as quaternary ammonium salts in the coating achieve efficient inhibition of bacterial attachment; 2) the introduction of amphiphilic chain segments in the coating achieves an antifouling effect of inhibiting diatom adhesion.

[0038] The results of the examples can prove that the antifouling coating prepared by the preparation method of the present invention has high optical transparency within the wavelength range of 350-800nm, and the transmittance is more than 85%; the results of the bacterial attachment inhibition experiment show that the coating can inhibit more than 90% of bacterial attachment; the results of the diatom inhibition experiment show that the coating can inhibit more than 90% of diatom attachment.

[0039] The antifouling coating prepared by the present invention has high optical transparency, good mechanical properties and antifouling properties, can realize rapid light curing, and can be suitable for surface protection of underwater vehicles, marine photovoltaic equipment, sensors and detectors and other equipment and facilities. The coating curing method of the present invention is light curing, which expands the application field of coating technology; in the resin preparation process of the present invention, only anhydrous ethanol can be used as a solvent, which can reduce the harm and impact of using organic solvents on the environment; the synergy of the antibacterial effect of the quaternary ammonium salt and other groups of the present invention and the amphiphilic interface antifouling achieve good antifouling effect; the polyurethane chain segment introduced by the present invention improves the mechanical properties of the coating.

[0040] Therefore, in view of the urgent need for transparent coating preparation and application technology in the field of marine antifouling, the present invention uses silicone resin with bactericidal properties as the main matrix, uses quaternary ammonium salts and other groups as antibacterial active sites, and prepares amphiphilic transparent antifouling coatings with composite methacrylate materials, and achieves high-efficiency antifouling with amphiphilic interfaces, so that the coating has good antibacterial and diatom adhesion inhibition properties. The characteristics of light curing have expanded the application field of the coating.

[0041] Compared with the prior art, the present invention has the following advantages:

[0042] 1. In the synthesis process of the present invention, only ethanol can be used as a solvent, which has the characteristics of low volatility and less harm to the environment;

[0043] 2. The coating curing process of the present invention is light-induced curing, which has the characteristics of high efficiency and low energy consumption;

[0044] 3. The coating of the present invention has the characteristics of high optical transparency;

[0045] 4. The coating of the present invention has good antibacterial activity and the ability to inhibit diatom attachment. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1The transparency test results of the glass sheet, the coating prepared in Example 1 and the coating prepared in Example 2 under the UV-visible light spectrum are shown in the figure. According to the results in the figure, in the wavelength range of 350-800nm, the coating has an optical transparency higher than 85%.

[0047] Figure 2 Fluorescence microscope images of glass slides, coatings prepared in Example 1, and coatings prepared in Example 2 immersed in Ampelopsis thaliana for one day. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only partial embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] Example 1

[0050] A method for preparing a light-cured transparent antifouling coating of the present invention comprises the following steps:

[0051] S1. 2.08 g of ethyl orthosilicate, 1.50 g of 65% dimethyloctadecyl[3-trimethoxysilylpropyl]ammonium chloride, 1.39 g of 3-(isomethacryloyloxy)propyltrimethoxysiloxane and 4 g of anhydrous ethanol were mixed, 1.40 g of 0.1 mol / L hydrochloric acid solution was added, and the mixture was reacted at 25° C. for 12 h. The obtained solution was subjected to rotary evaporation at 50° C. for 30 min to remove anhydrous ethanol to obtain a silicone resin.

[0052] S2. 55.5 g of isophorone diisocyanate and 40 g of polypropylene glycol polyol were mixed and stirred, the temperature was raised to 80 ° C, a small amount of catalyst dibutyltin dilaurate was added, and the reaction was carried out for 2.5 h to obtain an isocyanate group-terminated polyurethane prepolymer;

[0053] S3. The isocyanate group-terminated polyurethane prepolymer was cooled to 40°C, 41.6 g of hydroxyethyl methacrylate and 0.5 g of hydroquinone were slowly added, the temperature was raised to 55°C, and the reaction was carried out for 2.5 hours to obtain a methacrylic acid group-terminated polyurethane prepolymer;

[0054] S4. 2.10 g of silicone resin, 0.13 g of methacrylic acid group-terminated polyurethane prepolymer, 0.45 g of methacryloyloxypropyl-terminated polydimethylsiloxane, and 0.55 g of methacrylate polyethylene glycol methyl ether methacrylate were mixed, stirred at room temperature for 1 h, and ultrasonically vibrated for 20 min;

[0055] S5. 0.1 g of a photoinitiator 2-hydroxy-2-methyl-1-phenyl-1-propanone and 0.1 g of benzoin dimethyl ether were added to the resin obtained in S4 and ultrasonically vibrated for 20 min to obtain an antifouling resin;

[0056] S6. Apply the antifouling resin to the surface of the glass sheet by scraping, and place the antifouling resin coated with the coating under a UV initiation device for curing, and the curing time is 30 minutes.

[0057] The relevant properties and shapes of the tested coatings are as follows:

[0058] Test method for inhibiting the adhesion performance of bacteria (Escherichia coli, Staphylococcus aureus or Pseudomonas Xiamenensis). Place a glass slide and a coating sample coated in Example 1 in a bacterial culture solution of the same concentration for 24 hours, wash off the bacteria attached to the surface of the glass slide and the surface of the coating sample in Example 1, and culture on the surface of a solid culture medium for 24 hours. Calculate the number of bacterial colonies attached to the surface of the glass slide and the surface of the coating sample in Example 1, and set the number of bacterial colonies grown on the surface of the glass slide as a benchmark, calculate the reduction rate of bacterial attachment on the coating surface in Example 1, that is, the bacterial attachment inhibition rate of the coating, and the corresponding bacterial attachment inhibition rate is as follows:

[0059] Bacteria inhibition adhesion performance test results:

[0060] Xiamen Pseudoalteromonas inhibition rate: 96.3%

[0061] Staphylococcus aureus inhibition rate: 99.6%

[0062] E. coli inhibition rate: 96.0%

[0063] Test method for inhibiting diatom attachment performance. Figure 2 As shown, a glass sheet and a sample coated with the coating in Example 1 were placed in a culture solution of the same concentration of the dichaete diatom for 1 day, and the number of diatoms attached to the surface of the glass sheet and the surface of the coating sample in Example 1 was observed and measured by a fluorescence microscope. The number of diatoms attached to the surface of the glass sheet was set as a benchmark, and the reduction rate of diatom attachment on the coating surface was calculated, which was the diatom attachment inhibition rate of the coating. The corresponding diatom attachment inhibition rate was as follows:

[0064] Diatom inhibition adhesion performance test results:

[0065] Double eyebrow algae inhibition rate: 92.9%

[0066] The test result of glass surface coating adhesion conducted according to ASTM D4541-09 standard is: 2.30MPa.

[0067] The transmittance of the coating in the 350-800nm ​​band was investigated by UV-visible light spectroscopy. The transmittance of the coating exceeded 85%, proving the high optical transmittance of the coating. Figure 1 .

[0068] Example 2

[0069] Referring to Example 1, the difference from Example 1 is that the mass of the polyurethane prepolymer terminated with methacrylic acid group added in S4 is 0.26 g.

[0070] Bacteria inhibition adhesion performance test results:

[0071] Xiamen Pseudoalteromonas inhibition rate: 93.9%

[0072] Staphylococcus aureus inhibition rate: 99.1%

[0073] E. coli inhibition rate: 96.2%

[0074] Diatom inhibition adhesion performance test results:

[0075] Double eyebrow algae inhibition rate: 93.7%

[0076] The test result of glass surface coating adhesion conducted according to ASTM D4541-09 standard is: 2.22MPa.

[0077] The transmittance of the coating in the 350-800nm ​​band was investigated by UV-visible light spectroscopy. The transmittance of the coating exceeded 85%, proving the high optical transmittance of the coating. Figure 1 .

[0078] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the scope of protection of the present invention. All equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a light-cured transparent antifouling coating, characterized in that: The following steps are involved: S1. Preparation of functional silicone resin: reacting tetraethyl orthosilicate, a photoinitiator siloxane monomer and a functional siloxane monomer in a sol-gel system, and then removing the solvent to prepare a photocurable functional silicone resin; S2. reacting a diisocyanate monomer with a polyol to prepare an isocyanate group-terminated polyurethane prepolymer; S3. The isocyanate group-terminated polyurethane prepolymer, the methacrylic acid hydroxyl monomer and the polymerization inhibitor are mixed and reacted to prepare a methacrylic acid group-terminated polyurethane prepolymer; S4. Resin preparation: functional silicone resin, polyurethane prepolymer terminated with methacrylic acid hydroxyl monomer, methacrylic acid hydrophilic monomer and methacrylic acid hydrophobic monomer are mixed and stirred and ultrasonically vibrated to obtain a resin solution; S5. The photoinitiator is added to the resin solution obtained in S4, and ultrasonic oscillation is performed to obtain an antifouling resin; S6. Apply the antifouling resin to the surface of the substrate and cure it to form a completely cured transparent antifouling coating.

2. The method for preparing a light-curable transparent antifouling coating according to claim 1, characterized in that: In step S1, the photoinitiated siloxane monomer includes one or more of 3-(isomethacryloyloxy)propyl trimethoxysiloxane, vinyl trimethoxysiloxane, acryloxypropyl trimethoxysiloxane, acrylamidopropyl trimethoxysiloxane, methacryloxymethyl trimethoxysiloxane, 3-(N-allylamino)propyl trimethoxysiloxane, and acetoxypropyl trimethoxysiloxane; The functional siloxane monomer includes one or more of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, pentafluorophenylpropyltrimethoxysiloxane, 2-(2-pyridyl)ethyltrimethoxysiloxane, and tetramethylguanidinylpropyltrimethoxysiloxane.

3. The method for preparing a light-curable transparent antifouling coating according to claim 1, characterized in that: In step S1, the mass ratio of tetraethyl orthosilicate, photoinitiated siloxane monomer and functional siloxane monomer is 1:(0.1-1):(0.3-1.2).

4. The method for preparing a light-curable transparent antifouling coating according to claim 1, characterized in that: In step S2, the diisocyanate monomer includes one or more of isophorone diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate; the polyol includes one or more of polyethylene glycol, polypropylene glycol, and polytetrahydrofuran; and the mass ratio of the diisocyanate monomer to the polyol is 1:(0.6-1).

5. The method for preparing a light-curable transparent antifouling coating according to claim 1, characterized in that: In step S3, the hydroxyl methacrylate monomer includes one or both of hydroxyethyl methacrylate and hydroxypropyl methacrylate; and the mass ratio of the polyurethane prepolymer to the hydroxyl methacrylate monomer is 1:(0.2-0.5).

6. The method for preparing a light-curable transparent antifouling coating according to claim 1, characterized in that: In step S4, the mass ratio of the functional silicone resin to the polyurethane prepolymer terminated with a methacrylic acid hydroxyl monomer, the methacrylic acid hydrophilic monomer and the methacrylic acid hydrophobic monomer is: 1: (0.05-0.5): (0.1-0.5): (0.1-0.5).

7. The method for preparing a light-curable transparent antifouling coating according to claim 1, characterized in that: In step S5, the photoinitiator includes one or more of benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and hydroxycyclohexane phenone.

8. The method for preparing a light-curable transparent antifouling coating according to claim 1, characterized in that: In step S6, the substrate includes one or more of a steel sheet, a glass, a polymethacrylate sheet, a polycarbonate sheet, a polyethylene terephthalate sheet and a wood sheet; and / or the coating method is one of brushing, spin coating, scraping and dipping.

9. A photocurable transparent antifouling coating, characterized in that: The invention is prepared by the preparation method described in any one of claims 1 to 8.

10. Use of the photocurable transparent antifouling coating according to claim 9 in surface protection of equipment and facilities including marine photovoltaic equipment, underwater detection instruments, underwater sensors, underwater vehicles and visual windows.

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