Bionic super-hydrophobic marine antifouling coating with physicochemical synergistic effect and preparation method of bionic super-hydrophobic marine antifouling coating

Abstract

The invention belongs to the technical field of marine antifouling, and particularly relates to a bionic super-hydrophobic marine antifouling coating with a physicochemical synergistic effect and a preparation method of the bionic super-hydrophobic marine antifouling coating. The antifouling paint of the antifouling coating comprises an antifouling material and a super-hydrophobic material; the antifouling material comprises saccharin, gabapentin, p-toluenesulfonic acid and decanoic acid; the super-hydrophobic material comprises mixed resin and nano silicon dioxide, and the mixed resin comprises epoxy resin EP and organic silicon resin SR; the mass ratio of the super-hydrophobic material to the antifouling material is 10: (0.05-0.25); the percentage content of the epoxy resin in the mixed resin is 30-50%; the mass ratio of the mixed resin to the nano silicon dioxide is 8: (1.5-2.5); the mass ratio of the saccharin to the gabapentin to the p-toluenesulfonic acid to the capric acid is 32: (21-25): (36-40): (5-9). The coating provided by the invention has excellent super-hydrophobic performance and physicochemical synergistic antifouling performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of marine antifouling, and particularly relates to a bionic superhydrophobic marine antifouling coating with physical and chemical synergistic effects and a preparation method thereof. Background Art

[0002] During the process of developing and utilizing marine resources, a large number of microorganisms, animals, plants, etc. in the ocean will continuously settle and accumulate on marine equipment such as ships and submarines. Such a phenomenon is called marine biofouling. According to relevant statistics, the types of organisms causing biofouling in the ocean have exceeded 4,000, including about 600 plant fouling organisms and 100 animal organisms, and this is only a small part of the known marine organisms. In addition, the types of organisms causing marine fouling can also be classified into micro - attached organisms and macro - attached organisms according to the biological form and size. The former includes bacteria, diatoms, chlorella, etc.; the latter includes barnacles, mussels, and some large algae, etc. With the successive occurrence of the four stages of biofouling: conditioning film formation (attachment of organic molecules such as polysaccharides and proteins), biofilm formation (attachment of bacteria and single - cell algae, etc.), microbial attachment (attachment of fouling larvae, etc.), and macro - organism attachment (attachment of barnacles, mussels, etc.), the fouling phenomenon is thus formed.

[0003] The phenomenon of marine biofouling will cause a series of serious problems. First of all, marine biofouling will cause energy loss. When fouling organisms attach to the hull and grow continuously, the overall weight of the hull will also increase continuously, and the type of friction between the hull and the water body will also change, resulting in an increasing resistance during the operation of the ship, and thus consuming more energy, causing serious energy loss. At the same time, excessive energy consumption will emit more pollutants, causing further damage to the environment. In addition, during cross - sea transportation, the fouling organisms attached to the hull are also very likely to be carried to different seas, increasing the risk of alien species invasion in each sea area and posing a threat to the ecological balance of the local sea area. Therefore, with the continuous exploration of marine resources, the development of efficient marine antifouling has important practical significance for the country's infrastructure construction, economic development, and environmental governance, etc.

[0004] To solve the problem of marine biofouling, in the 17th century, researchers added copper ions to the antifouling coating to achieve the antifouling purpose; in the mid - to - late 18th century, antifouling coatings mainly based on toxicity - releasing substances such as mercury and arsenic were widely used; since the 1960s, organotin coatings have become the antifouling coatings with the most significant antifouling effect. However, with the International Maritime Organization's ban on the use of organotin coatings in 2008, people have gradually shifted the research focus to the development of environmentally friendly antifouling coatings.

[0005] With the development of technology and in-depth research, researchers have found that many organisms in nature have evolved different defense mechanisms that can inhibit the attachment or growth of fouling organisms in an environmentally friendly way, and these mechanisms also provide new ideas for alternative traditional anti-fouling methods. The research and mimicking processing of these natural mechanisms is called bionics, and bionic coatings have gradually become a research hotspot. Bionic coatings generally can be developed from three dimensions: physical structure bionics, chemical composition bionics, and physiological mechanism bionics, including bionic surface structures, bionic anti-fouling components, and bionic biological behaviors respectively.

[0006] Breakthrough progress has been made in the research of anti-fouling coatings, but there are still some problems: ① The current use of anti-fouling strategies is relatively single. Researchers have continuously explored nature and developed different types of anti-fouling coatings based on the anti-fouling mechanisms of different organisms, but the practice of combining different anti-fouling mechanisms still needs to be further strengthened; ② The preparation process is cumbersome and the application scale is limited. The preparation processes of most current anti-fouling coatings are complex and costly, and most processing methods are only suitable for fine processing in the laboratory and are difficult to achieve large-scale preparation. In addition, the outdoor conditions are harsh and the volume of transportation equipment such as ships is large, so the laboratory processing methods are limited; ③ It is difficult to balance the mechanical properties and anti-fouling properties of the coating. In the current process of preparing anti-fouling coatings, attention is often focused on the anti-fouling properties of the coating while ignoring the mechanical properties of the coating, which may lead to the coating being easily damaged by impact or physical wear and losing its original properties; ④ There are challenges in constructing environmentally friendly and easily processed superhydrophobic coatings. Currently, common methods such as spraying often rely on pre-fluorination treatment of materials to maintain the superhydrophobicity of the materials, which also causes serious damage to the environment. Developing coatings that can achieve both environmental protection and high anti-fouling performance remains a key problem to be solved in this field. Summary of the Invention

[0007] To solve the above technical problems such as the relatively single use of anti-fouling strategies, unstable mechanical properties of the coating, and cumbersome process flow, the present invention draws inspiration from natural anti-fouling mechanisms such as the superhydrophobicity of lotus leaves and the biochemical defense of coral mucus, and develops a bionic superhydrophobic marine anti-fouling coating containing a coral mucus derivative and its preparation method. This bionic design combines the physical anti-adhesion of the superhydrophobic surface with the chemical repellency of the anti-fouling agent to produce excellent anti-fouling performance.

[0008] To achieve the above invention purpose, the present invention adopts the following technical solutions:

[0009] The first aspect of the present invention discloses a bionic superhydrophobic marine antifouling coating with physical and chemical synergistic effects, which includes an antifouling material and a superhydrophobic material. The antifouling material includes saccharin, gabapentin, p-toluenesulfonic acid, and capric acid; the superhydrophobic material includes a mixed resin and nano-silica. The mixed resin includes epoxy resin EP and silicone resin SR; the mass ratio of the superhydrophobic material to the antifouling material is 10:0.05 to 0.25; in the mixed resin, the percentage content of epoxy resin is 30% to 50%; the mass ratio of the mixed resin to nano-silica is 8:1.5 to 2.5; the mass ratio of saccharin, gabapentin, p-toluenesulfonic acid, and capric acid is 32:21 to 25:36 to 40:5 to 9.

[0010] In the above technical solution, further, the epoxy resin is one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, phenolic epoxy resin, hydrogenated bisphenol A epoxy resin, bisphenol S epoxy resin, bio-based epoxy resin, aliphatic glycidyl ether epoxy resin, or brominated epoxy resin; the silicone resin is one or more of polyalkyl silicone resin, polyaryl silicone resin, methylphenyl silicone resin, acrylate-modified silicone resin, epoxy-modified silicone resin, or polyalkylaryl silicone resin; the nano-silica is a gas-phase hydrophobic nano-scale silica particle with a particle size of 7 to 40 nm. The epoxy resin rich in strong polar groups can increase the adhesion of the coating to the substrate. Its excellent corrosion resistance and mechanical properties can increase the mechanical strength of the coating; the silicone resin has the characteristics of low surface energy, and in addition, it has excellent moisture resistance, hydrophobicity, and chemical corrosion resistance, making the surface have obvious hydrophobicity and antifouling properties. The coating formed by the resin obtained by mixing the two shows excellent mechanical properties such as adhesion and abrasion resistance, and has good hydrophobicity.

[0011] In the above technical solution, further, the preparation method of the antifouling coating includes the following steps:

[0012] (1) Prepare the first solution: Mix epoxy resin, silicone resin, antifouling material, and the first solvent evenly according to the ratio, and the mixing temperature is 65 to 75 °C;

[0013] (2) Prepare the second solution: Mix nano-silica, ammonia water, and the second solvent evenly, and the mixing temperature is 65 to 75 °C; During the preparation of the silica suspension, ammonia water is added. The main function of ammonia water is to create an alkaline environment to better disperse the silica particles in the solution, further increase the contact area between the silica particles and the mixed resin, and make it easier to spread out to form a uniform and stable micro-nano structure after subsequent spraying, improving the hydrophobicity.

[0014] (3) Mix the first solution and the second solution, heat and stir evenly at 65 to 75 °C, and let the solvent evaporate; cool down.

[0015] In the above technical solution, further, the first solvent includes one or more of toluene, ethyl acetate, and butyl acetate; the second solvent includes one or more of absolute ethanol, acetone, n-hexane, and carbon tetrachloride;

[0016] In step (1), the epoxy resin, silicone resin, antifouling material, and first solvent are in a mass ratio of 16:22-26:0.5-1.5:33-37;

[0017] In step (2), the mass ratio of nano-silica, ammonia water, and the second solvent is 10:0.5-1.5:48-52.

[0018] In the above technical solution, further, during the mixing in step (1), stirring is performed, the stirring speed is 600-800 r / min, and the stirring time is 1-3 h;

[0019] The stirring time in step (3) is 1-3 h, and the stirring speed is 600-800 r / min.

[0020] In the second aspect of the present invention, a bionic superhydrophobic marine antifouling coating with physical and chemical synergistic effects is provided, which is characterized by including a substrate and a coating, and the coating is the aforementioned coating.

[0021] In the above technical solution, further, the substrate includes metal, glass, plastic, stone, or wood, and the shape of the substrate is flat or curved.

[0022] In the above technical solution, further, the preparation method of the antifouling coating includes: adding a curing agent to the antifouling paint, then spraying it onto the surface of the substrate, and drying it in an environment of 25-100 °C for 0.5-24 h for curing after spraying, and the cured product is obtained.

[0023] In the above technical solution, further, the curing agent is an amine curing agent, including ethylenediamine, diethylenetriamine, triethylenetetramine, or low molecular weight polyamide, and the mass ratio of the curing agent to the mixed resin is 1:3-5.

[0024] In the above technical solution, further, the spraying tool is a spray gun, the nozzle diameter of the spray gun is 0.5-1.0 mm, the spray shape is adjusted to be linear, the spraying flow rate is set to 75-85 mL / min, the spraying pressure is 0.35-0.4 MPa, the distance between the nozzle and the substrate is kept at 10-20 cm, perpendicular to the surface of the substrate, at an angle of 40-50° with the horizontal plane, and spraying is performed from left to right at a speed of 9-11 cm / s, and spraying is repeated 15-25 times; the substrate is cleaned before spraying.

[0025] Compared with the prior art, the beneficial effects of the present invention:

[0026] The present invention takes the superhydrophobic antifouling mechanism of lotus leaves, the mucus secreted by corals themselves, and their mucus release mechanism as the bionic objects, and uses silicone resin, epoxy resin, nano-silica particles and antifouling components to prepare a bionic superhydrophobic marine antifouling coating with a physical and chemical synergistic effect. This coating combines the antifouling mechanisms of the two organisms well. First, the micro-nano structure on the surface of the coating and the low surface energy of the coating itself endow the coating with superhydrophobic properties, which make the coating unable to be wetted by seawater, and it is difficult for fouling organisms in seawater to adhere to the surface of the coating. Second, as time goes by, when the hydrophobic property on the surface gradually weakens, the coral mucus-like antifouling components inside the coating are released into the ocean accordingly, continuing the antifouling performance.

[0027] The coating of the present invention has shown stable superhydrophobic properties after different mechanical property tests, and to a certain extent solves the problem that the micro-nano structure of the superhydrophobic surface is fragile and easily damaged; in addition, it has also shown excellent synergistic antifouling performance after different antifouling tests.

[0028] The present invention prepares the required antifouling coating by a one-step spraying method, which is very convenient and efficient, and can realize the preparation of a large number of samples in a short time.

[0029] The raw materials used in the present invention to prepare the antifouling coating all have the characteristics of environmental friendliness, and do not require the use of fluorine-containing reagents, meeting the current industrial development prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a parameter optimization data graph of Example 1; Figure 1 (a) shows the effect of increasing the percentage of epoxy resin (EP) in the mixed resin on the wettability of the coating; Figure 1 (b) shows the effect of increasing the percentage of epoxy resin (EP) in the mixed resin on the adhesion of the coating; Figure 1 (c) shows the effect of increasing the percentage of epoxy resin (EP) in the mixed resin on the abrasion resistance of the coating; Figure 1 (d) shows the effect of increasing the percentage content of silica in the mixed resin system on the wettability of the coating; Figure 1 (e) shows the effect of increasing the percentage content of silica in the mixed resin system on the adhesion of the coating; Figure 1 (f) shows the effect of increasing the percentage content of silica in the mixed resin system on the abrasion resistance of the coating; Figure 1 (g) shows the effect of increasing the percentage content of the antifouling component in the mixed resin-silica system on the wettability of the coating; Figure 1 (h) shows the effect of increasing the percentage content of the antifouling component in the mixed resin-silica system on the adhesion of the coating; Figure 1(i) shows the effect of increasing the percentage content of the antifouling component in the hybrid resin-silica system on the release performance of the coating.

[0031] Figure 2 Optical and electron microscopy images of the superhydrophobic bionic antifouling coating of Example 2 of the present invention; Figure 2 (a) Macroscopic optical image of the superhydrophobic bionic antifouling coating and optical images of the surface structure and coating thickness under a super-depth-of-field microscope; Figure 2 (b) Scanning electron microscope image of the coating surface structure; Figure 2 (c) Schematic diagram of the contact angle of the liquid droplet on the coating surface.

[0032] Figure 3 Fourier transform infrared spectroscopy (FTIR) spectrum of the coating of Example 2 of the present invention; Figure 3 (a) FTIR spectra of the superhydrophobic bionic antifouling coating (SHAC) and the superhydrophobic coating (SHC); Figure 3 (b) FTIR spectra of the superhydrophobic bionic antifouling coating with a single antifouling component (from top to bottom: decanoic acid, saccharin, gabapentin, p-toluenesulfonic acid).

[0033] Figure 4 X-ray photoelectron spectroscopy (XPS) spectrum and antifouling component structure diagram of the coating of Example 2 of the present invention; Figure 4 (a) XPS spectra of the superhydrophobic bionic antifouling coating and the superhydrophobic coating; Figure 4 (b) Antifouling component structure diagram inside the coating.

[0034] Figure 5 Wear resistance test diagram of the superhydrophobic bionic antifouling coating; Figure 5 (a) Flow chart of the linear wear experiment; Figure 5 (b) Change in coating wettability with the number of friction cycles.

[0035] Figure 6 Peel resistance test diagram of the superhydrophobic bionic antifouling coating; Figure 6 (a) Microscopic structure diagram and contact angle schematic diagram of the coating before and after the tape peeling experiment; Figure 6 (b) Change in coating wettability with the number of tape peeling times.

[0036] Figure 7 Antibacterial effect diagrams corresponding to superhydrophobic bionic antifouling coatings with different contents of antifouling components.

[0037] Figure 8 Anti-algal effect diagrams corresponding to superhydrophobic bionic antifouling coatings with different contents of antifouling components. Detailed implementation manners

[0038] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited in any way.

[0039] Example 1

[0040] Experimental method:

[0041] 1. In the present invention, the specific ratio of the mixed resin is determined by investigating the wettability and mechanical properties.

[0042] The surface wettability of the pure silicone resin coating (SR) was detected using a contact angle measuring instrument, and it was found that the contact angle (CA) of the liquid droplet on the coating surface was 120° ( Figure 1 (a)), confirming its hydrophobicity. However, after 20 times of strong peeling with 3M tape, it was found that the adhesion between the coating and the substrate was poor (ASTM 2B standard).

[0043] Epoxy resin (EP) was mixed in the silicone resin. As the EP content increased to 40%, the adhesion of the coating had been improved to ASTM 4B standard. However, after the EP content was greater than 40%, the hydrophobicity was reduced, making the coating hydrophilic (CA < 90°, Figure 1 (a), (b)). After the sample was placed on the sandpaper and rubbed cyclically 100 times, it was found that the higher the EP content, the stronger the wear resistance ( Figure 1 (c)), and when the EP content was less than 40%, the wear rate exceeded 10%.

[0044] The silicone resin used was methyl vinyl MQ silicone resin, and the epoxy resin used was bisphenol A epoxy resin.

[0045] 2. In the mixed resin, by adding nano-silica, a micro / nano structure was constructed to enhance the superhydrophobicity. Fixing the mass ratio of EP and SR at 4:6, the total mixed mass: 8.0 g, the increase in the SiO2 content improved the CA ( Figure 1 (d)), and the CA reached 156° (sliding angle = 6°) at a SiO2 content of 20%, while maintaining sufficient adhesion (ASTM 3B standard). SEM imaging confirmed that the SiO2 particles were firmly embedded in the resin matrix ( Figure 2 (b)). However, excessive SiO2 (>20%) would reduce the mechanical properties, reduce the adhesion to the substrate (ASTM 2B), and make the wear rate exceed 10% ( Figure 1 (e), (f)).

[0046] 3. In order to integrate the antifouling function, coral mucus-derived components were incorporated into the optimized resin-silica system. Through contact angle testing and mechanical property testing, it was found that the change in the content of the antifouling component had a negligible effect on the wettability or mechanical properties ( Figure 1 (g), (h)). The release kinetics monitored by UV-Vis within 30 days ( Figure 1(i) indicates that when the content of the antifouling component exceeds 2.0%, the release performance is stable.

[0047] The antifouling components used are saccharin, gabapentin, p-toluenesulfonic acid, and capric acid, mixed in a mass ratio of 32:23:38:7.

[0048] 4. FTIR and XPS analyses confirmed the successful integration of the components, and the characteristic peaks ( Figure 3 ) and S2p / N 1s signals ( Figure 4 ) confirmed their existence.

[0049] Example 2

[0050] Prepare a biomimetic superhydrophobic marine antifouling coating with a physical and chemical synergistic effect. The mass ratio of epoxy resin: silicone resin: silica: antifouling component = 16:24:10:1. The preparation includes the following steps:

[0051] (1) Select a 50×50×1.5 mm polypropylene plate (pp) as the substrate material. After soaking it in absolute ethanol, ultrasonic cleaning, drying, place it in a plasma processor and process it at a power of 200 W for 6 min, and finally place it on the spraying platform.

[0052] (2) Prepare the first solution: Mix 3.2 g of bisphenol A epoxy resin with 4.8 g of methyl vinyl MQ silicone resin. Take 7 g of butyl acetate as the first solvent, add 0.2 g of the antifouling component, and place it on a magnetic stirrer and stir for 1 h to obtain a mixed resin solution containing the antifouling component. The antifouling components are saccharin, gabapentin, p-toluenesulfonic acid, and capric acid, mixed in a mass ratio of 32:23:38:7.

[0053] (3) Prepare the second solution: Weigh 2.0 g of silica particles with a particle size of 7 - 40 nm, 10 g of absolute ethanol, and 0.2 g of ammonia water, mix them and place them on a magnetic stirrer and stir for 2 h to obtain a silica suspension.

[0054] (4) After stirring evenly, mix the first solution and the second solution, and stir while heating at 75 °C for 1.5 h; after the mixed coating naturally cools to room temperature, add 1.5 g of ethylenediamine and 0.5 g of diethylenetriamine mixed curing agent, and disperse to form a fluorine-free superhydrophobic antifouling coating.

[0055] (5) Use an R51-F type 0.8 mm caliber top-mounted spray gun for spraying operations. During the spraying process, set the air pressure to 0.4 MPa, the spraying flow rate to 80 mL / min, the distance between the spray gun nozzle and the substrate to 15 cm, and perpendicular to the substrate surface. During the whole process, the spray gun moves from left to right at a speed of 10 cm / s, spray 15 times, and after finishing, place it in a 60 °C vacuum drying oven and cure for 3 h to obtain a superhydrophobic biomimetic antifouling coating (SHAC).

[0056] In addition, according to the above preparation method, the difference is that in step (2), 0.2 g of the antifouling component is not added to prepare a superhydrophobic coating (SHC); according to the above preparation method, the difference is that in step (2), 0.2 g of saccharin, 0.2 g of gabapentin, 0.2 g of p-toluenesulfonic acid or 0.2 g of capric acid are respectively added to prepare 4 kinds of superhydrophobic coatings with a single antifouling component added.

[0057] Example 3

[0058] Perform performance tests on the coatings prepared in Example 2:

[0059] 1. Detect the surface morphology of the superhydrophobic bionic antifouling coating:

[0060] Use an optical camera and a super-depth-of-field microscope to record the macroscopic image of the superhydrophobic bionic antifouling coating and the optical microscope image magnified 200 times respectively. As Figure 2 (a) shows, the thickness of the superhydrophobic bionic antifouling coating prepared in Example 2 is 175 nm.

[0061] Use a scanning electron microscope to characterize the surface morphology of the coating. The magnification under the scanning electron microscope is 200 times as Figure 2 (b) shows. In addition, uneven micro-scale structures can be seen under the electron microscope. These structures are formed by the aggregation of hydrophobic silica and combined with the resin during the spraying process, providing conditions for the superhydrophobic performance.

[0062] 2. Detect the superhydrophobic performance of the superhydrophobic bionic antifouling coating

[0063] Use a TBU 100 contact angle measuring instrument to measure the contact angle of the sample. The water droplet size is 5 μL, the fitting method is polynomial fitting, and the calculation method is the tangent method. 5 points are selected for each sample for measurement. The rolling angle of the sample surface is measured by the inclined plate method: before measurement, level the sample stage first, take 5 μL of deionized water with a micro-meter, drop it on the sample surface, and slowly rotate the sample stage until the water droplet starts to move. Record the angle turned by the sample stage at this time as the rolling angle. At least 5 points are selected for each sample for measurement. All measurements are carried out at room temperature. The measured contact angle of the sample surface is 156° ( Figure 2 (c)), and the rolling angle is 7°.

[0064] 3. Characterize the functional group composition of the superhydrophobic bionic antifouling coating

[0065] Characterize the superhydrophobic bionic antifouling coating (SHAC), superhydrophobic coating (SHC) and superhydrophobic coating with a single antifouling component added by a Fourier transform infrared spectrometer (FITR). Figure 3(a) It was found that the superhydrophobic bionic antifouling coating contains unique absorption peaks different from those of the superhydrophobic coating. Further, by comparing with the infrared spectrum of the superhydrophobic coating with a single antifouling component in Figure 3 (b), it was found that the characteristic peaks in the superhydrophobic bionic antifouling coating all originate from the four internal antifouling components. The above analysis not only reveals the specific composition and functional group characteristics of the superhydrophobic antifouling coating, but also reflects that the entire preparation process does not involve chemical bonding, but only simple physical bonding.

[0066] 4. Characterize the elemental composition of the superhydrophobic bionic antifouling coating

[0067] The superhydrophobic bionic antifouling coating (SHAC) and the superhydrophobic coating (SHC) were characterized by X-ray photoelectron spectroscopy. Figure 4 (a) It was found that both coatings contain three elements: O, C, and Si. From the coating components, this indicates that all three elements are derived from silicone resin, epoxy resin, and SiO2. Different from that, in the superhydrophobic bionic antifouling coating, we found two elements, N1s and S2p, but these elements were not detected in the superhydrophobic coating. By studying the chemical structural formulas of saccharin, gabapentin, n-decanoic acid, and p-toluenesulfonic acid, it was found that these two elements all come from the antifouling components, which also indicates that the antifouling components have been successfully introduced into the antifouling coating. In addition, the elemental composition of O, C, Si, N, and S shows that the superhydrophobic bionic antifouling coating does not contain F, further confirming the environmentally friendly characteristics of the superhydrophobic antifouling coating.

[0068] 5. Detect the wear resistance of the superhydrophobic bionic antifouling coating

[0069] The sample was placed on 800-mesh sandpaper, with the coating surface in contact with the sandpaper, and a 100-g weight was placed on the sample. The sample was pushed along the ruler with forceps, and the pushing distance was 20 cm. Then the sample was pushed back to the origin from the other side in the opposite direction. This process was defined as one friction cycle, and the experimental diagram is as shown in Figure 5 (a). The change in surface wettability was recorded every 10 friction cycles. The results show that after 100 friction cycles, the coating can still exhibit stable superhydrophobic performance, and the results are as shown in Figure 5 (b).

[0070] 6. Detect the adhesion between the superhydrophobic bionic antifouling coating and the substrate

[0071] Place the sample on a platform with sufficient hardness. Hold the handle of the cross cutter, keep the blade perpendicular to the sample surface, and cross-cut the sample surface at a steady speed (20 mm / s) with uniform pressure to form a grid array pattern. Clean the debris on the sample surface with a soft brush. Stick the tape tightly on the grid array pattern, apply a certain pressure with your finger, and then peel off the tape from the sample surface at a uniform speed after sticking tightly. Observe the remaining situation of the surface coating and measure the contact angle at this position. The comparison before and after the surface is as Figure 6 (a) shown. After 100 times of tape peeling, the coating still showed stable superhydrophobic performance. The experimental results are as Figure 6 (b) shown.

[0072] 7. Detect the antibacterial performance of the superhydrophobic bionic antifouling coating

[0073] According to the preparation method of Example 2, the proportion of the antifouling component is 0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5% respectively. Immerse the superhydrophobic bionic antifouling coating (SHAC x ) with the physicochemical synergistic effect of different contents of antifouling components in Escherichia coli solution and culture for 24 h. After the experiment, rinse the sample 2 - 3 times, dilute the last washing solution and spread it on the solid LB medium, culture for 48 h and observe the growth of colonies on the medium. The results show that the superhydrophobic coating (SHC) has a certain antifouling effect, but the samples containing antifouling components have a more significant inhibitory effect on bacteria, and with the increase of the culture time, the antibacterial effect is more obvious. In addition, with the increase of the content of the antifouling component, the antibacterial effect continuously increases. The results are as Figure 7 shown.

[0074] 8. Detect the anti-algal performance of the superhydrophobic bionic antifouling coating

[0075] Immerse the superhydrophobic bionic antifouling coating (SHAC x ) with the physicochemical synergistic effect of different percentages of antifouling components in Chlorella solution and culture for 14 days. After the experiment, rinse the sample 2 - 3 times, place the sample under a fluorescence microscope for observation, and the bright spots in the field of view are the attached Chlorella. The results show that the superhydrophobic coating (SHC) has a certain antifouling effect, but the samples containing antifouling components have a more significant inhibitory effect on Chlorella, and with the increase of the culture time, the anti-algal effect is more obvious. In addition, with the increase of the content of the antifouling component, the anti-algal effect continuously increases. The results are as Figure 8 shown.

[0076] The anti-fouling coating of the present invention has a first line of defense, which is its superhydrophobic surface. A trapped air film on the surface minimizes water contact and prevents dirt adhesion. The hybrid resin of the present invention combines the low surface energy of SR and the mechanical robustness of EP (abrasion and corrosion resistance), strengthening this main barrier. The superhydrophobic surface combines micro / nanostructures and low surface energy materials to capture an air cushion and prevent microbial attachment. Experiments have shown that the lotus leaf surface can physically damage the bacterial membrane, achieving anti-fouling without the need for chemicals. However, superhydrophobic coatings are easily damaged mechanically, and the trapped air will escape under high pressure, leading to biofouling. But for the anti-fouling coating of the present invention, when the superhydrophobic interface is damaged, the embedded coral mucus anti-fouling component is released as a secondary defense to further inhibit fouling organisms and improve the overall performance, providing effective biofouling prevention.

[0077] Example 4

[0078] In this example, a 50×50×1.5 mm stainless steel plate was selected as the substrate material. After being immersed in absolute ethanol and ultrasonically cleaned, it was dried and placed on the spraying platform.

[0079] 2.4 g of bisphenol A epoxy resin was mixed with 5.6 g of methyl vinyl MQ silicone resin. 7 g of butyl acetate was taken as the first solvent, and 0.2 g of anti-fouling component was added. It was placed on a magnetic stirrer and stirred for 1 h to obtain a mixed resin solution containing the anti-fouling component.

[0080] 2.0 g of silicon dioxide particles with a particle size of 7 - 40 nm, 10 g of absolute ethanol, and 0.2 g of ammonia water were weighed and mixed. They were placed on a magnetic stirrer and stirred for 2 h to obtain a silicon dioxide suspension.

[0081] After stirring evenly, the mixed resin solution and the silicon dioxide suspension were mixed, and stirred at 75 °C for 1.5 h while heating. After the mixed coating was naturally cooled to room temperature, 1.5 g of ethylenediamine and 0.5 g of diethylenetriamine mixed curing agent were added and dispersed to form a fluorine-free superhydrophobic anti-fouling coating.

[0082] An R51-F type 0.8 caliber top pot spray gun was used for spraying. During the spraying process, the air pressure was set to 0.4 MPa, the spraying flow rate was 80 mL / min, the distance between the spray gun nozzle and the substrate was 15 cm, and it was perpendicular to the substrate surface. The spray gun moved from left to right at a speed of 10 cm / s throughout the process and was sprayed 15 times. After that, it was placed at room temperature of 25 °C for curing for 24 h to obtain a superhydrophobic bionic anti-fouling coating.

[0083] Example 5

[0084] In this example, a 30×15×1.5 mm glass plate was selected as the substrate material. After being immersed in absolute ethanol and ultrasonically cleaned, it was dried and placed on the spraying platform.

[0085] Mix 2.4 g of bisphenol A epoxy resin with 5.6 g of methyl vinyl MQ silicone resin. Take 7 g of butyl acetate as the first solvent, add 0.2 g of antifouling component, and place it on a magnetic stirrer and stir for 1 h to obtain a mixed resin solution containing the antifouling component.

[0086] Weigh 2.0 g of silica particles with a particle size of 7 - 40 nm, 10 g of absolute ethanol, and 0.2 g of ammonia water. Mix them and place them on a magnetic stirrer and stir for 2 h to obtain a silica suspension.

[0087] After stirring evenly, mix the mixed resin solution with the silica suspension, and stir while heating at 75 °C for 1.5 h. After the mixed coating is naturally cooled to room temperature, add 1.5 g of ethylenediamine and 0.5 g of diethylenetriamine mixed curing agent, and disperse to form a fluorine-free superhydrophobic antifouling coating.

[0088] Use an R51-F type 0.8 caliber top-feed spray gun for spraying operations. During spraying, set the air pressure to 0.4 MPa, the spraying flow rate to 80 mL / min, the distance between the spray gun nozzle and the substrate to 15 cm, and perpendicular to the substrate surface. During the whole process, the spray gun moves from left to right at a speed of 10 cm / s, spray 15 times, and after completion, place it in a vacuum drying oven at 100 °C for curing for 1 h to obtain a bionic antifouling coating.

[0089] The above embodiments only represent the implementation modes of the present invention, but should not be construed as limiting the scope of the present invention patent. It should be noted that for those skilled in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A bionic superhydrophobic marine antifouling coating with physicochemical synergistic effect, characterized in that It includes an antifouling material and a superhydrophobic material. The antifouling material includes saccharin, gabapentin, p-toluenesulfonic acid, and capric acid. The superhydrophobic material includes a mixed resin and nano-silica. The mixed resin includes epoxy resin EP and silicone resin SR. The mass ratio of the superhydrophobic material to the antifouling material is 10:0.05 - 0.

25. In the mixed resin, the percentage content of epoxy resin is 30% - 50%. The mass ratio of the mixed resin to nano-silica is 8:1.5 - 2.

5. The mass ratio of saccharin, gabapentin, p-toluenesulfonic acid, and capric acid is 32:21 - 25:36 - 40:5 - 9.

2. The antifouling coating according to claim 1, characterized in that, The epoxy resin is one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, phenolic epoxy resin, hydrogenated bisphenol A epoxy resin, bisphenol S epoxy resin, bio-based epoxy resin, aliphatic glycidyl ether epoxy resin, or brominated epoxy resin. The silicone resin is one or more of polyalkyl silicone resin, polyaryl silicone resin, methylphenyl silicone resin, acrylate-modified silicone resin, epoxy-modified silicone resin, or polyalkylaryl silicone resin. The nano-silica is a gas-phase hydrophobic nano-scale silica particle with a particle size of 7 - 40 nm.

3. The antifouling coating according to claim 1 or 2, characterized in that, The preparation method of the antifouling coating includes the following steps: (1) Prepare the first solution: Mix epoxy resin, silicone resin, antifouling material, and the first solvent evenly according to the ratio, and the mixing temperature is 65 - 75 °C. (2) Prepare the second solution: Mix nano-silica, ammonia water, and the second solvent evenly, and the mixing temperature is 65 - 75 °C. (3) Mix the first solution and the second solution, heat and stir evenly at 65 - 75 °C, and let the solvent evaporate; then cool.

4. The antifouling coating according to claim 3, characterized in that, The first solvent includes one or more of toluene, ethyl acetate, and butyl acetate. The second solvent includes one or more of absolute ethanol, acetone, n-hexane, and carbon tetrachloride. In step (1), the mass ratio of epoxy resin, silicone resin, antifouling material, and the first solvent is 16:22 - 26:0.5 - 1.5:33 - 37. In step (2), the mass ratio of nano-silica, ammonia water, and the second solvent is 10:0.5 - 1.5:48 - 52.

5. The antifouling coating according to claim 3, characterized in that, During the mixing in step (1), stir, and the stirring speed is 600 - 800 r / min, and the stirring time is 1 - 3 h. The stirring time in step (3) is 1 - 3 h, and the stirring speed is 600 - 800 r / min.

6. A bionic superhydrophobic marine antifouling coating with physical and chemical synergistic effects, characterized in that, It includes a substrate and a coating, and the coating is the coating according to any one of claims 1 - 5.

7. The anti-fouling coating according to claim 6, characterized in that, The substrate includes metal, glass, plastic, stone, or wood, and the shape of the substrate is flat or curved.

8. The anti-fouling coating according to claim 6, wherein The preparation method of the antifouling coating includes: Add a curing agent to the antifouling coating, then spray it onto the surface of the substrate, and place it in an environment of 25 - 100 °C to dry for 0.5 - 24 h for curing, and then the cured product is obtained.

9. The anti-fouling coating according to claim 8, characterized in that, The curing agent is an amine curing agent, including ethylenediamine, diethylenetriamine, triethylenetetramine, or low molecular weight polyamide. The mass ratio of the curing agent to the mixed resin is 1:3 - 5.

10. The anti-fouling coating according to claim 8, wherein, The spraying is carried out by using a spray gun. The nozzle diameter of the spray gun is 0.5 - 1.0 mm. Adjust the spray pattern to be linear. Set the spraying flow rate at 75 - 85 mL / min, the spraying pressure at 0.35 - 0.4 MPa. Keep the distance between the nozzle and the substrate at 10 - 20 cm, perpendicular to the substrate surface, and at an angle of 40 - 50° with the horizontal plane. Spray from left to right at a speed of 9 - 11 cm / s and repeat spraying 15 - 25 times; the substrate is cleaned before spraying.

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