A water-based organic corrosion-resistant antifouling transparent coating in marine environment and a preparation method and application thereof

Abstract

The present application belongs to the technical field of marine water-based organic coating, and specifically discloses a water-based organic corrosion-resistant and antifouling transparent coating in marine environment, a preparation method and application thereof. The present application uses water-based epoxy-modified silicone resin as a film-forming material, silane coupling agent as a curing agent, and carboxylated graphene oxide as an antibacterial functional factor, successfully synthesizes a water-based antifouling coating through ultrasonic oscillation and mechanical stirring. The synthesized coating has excellent antifouling and corrosion-resistant performance in seawater and sulfate-reducing bacteria solution, and has excellent hydrophobic performance. Moreover, no pollutants are generated in the preparation and use process of the coating, and the coating has good environmental friendliness.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of marine water-based organic coating, in particular to a water-based organic corrosion-resistant and antifouling transparent coating in marine environment and a preparation method and application thereof. BACKGROUND

[0002] Underwater detection equipment plays a crucial role in the fields of marine exploration, marine engineering, and scientific research. However, due to long-term exposure to underwater environments, these equipment often suffer from severe corrosion and microbial attachment problems, leading to a decrease in the visual performance of observation devices. Currently, the optical window antifouling technology for underwater instruments mainly relies on mechanical wiping, polishing, and ultrasonic cleaning methods, but these methods are inefficient and cause significant damage to the equipment. Therefore, there is an urgent need to develop a high-efficiency and environmentally friendly transparent marine antifouling coating to protect the core components of marine equipment such as detection lenses and optical probes.

[0003] In the current technology, many transparent coatings exhibit limited resistance when facing corrosive and fouling environments. The application of traditional coatings in underwater environments has some limitations, and conventional coatings may lose their durability and transparency due to the erosion of chemicals, microorganisms, marine organisms, and suspended matter in the underwater environment. These factors lead to the appearance of stains, corrosion, attachments, and microbial growth on the surface of the coating, reducing the clarity and reliability of observation devices.

[0004] Patent CN 116731574 A discloses a tin-free self-polishing antifouling coating and its preparation method. The coating uses cuprous oxide as an antifouling agent, exhibiting inhibition and inactivation effects on marine fouling organisms, with broad-spectrum and efficient antifouling effects. However, relevant studies have shown that cuprous oxide can have acute and chronic toxic effects on aquatic organisms, thereby potentially affecting the balance of aquatic ecosystems, and antifouling coatings containing cuprous oxide have been listed by the state as "high pollution, high environmental risk". Patent CN 116535585 A discloses a preparation method of a water-based transparent coating, which can be UV-cured and has the characteristics of hydrophobicity, transparency, wear resistance, stability, and good flexibility. However, the perfluoropolyether acrylate introduced during the preparation process has potential carcinogenic risks and will continuously accumulate in the body through the food chain. Patent CN201911106363 discloses a low-surface-energy water-based self-polishing emulsion, its preparation method, and a low-surface-energy water-based self-polishing drag-reducing antifouling coating, which has the characteristics of environmental friendliness and excellent stability. However, the film-forming material of this coating still has certain limitations in its own antifouling performance, and can only play an antifouling effect under the action of dynamic water flow of seawater shear force, and cannot effectively prevent fouling under static conditions. SUMMARY

[0005] To solve the above problems, one of the purposes of the present application is to provide a water-based organic corrosion-resistant antifouling transparent coating in marine environment, which has the characteristics of good antifouling and microbial anti-adhesion performance, environmental protection, no pollution, simple preparation and the like, and ensures the clarity and reliability of underwater detection equipment.

[0006] To achieve the above purpose, the specific technical solutions adopted by the present application are as follows:

[0007] A water-based organic corrosion-resistant antifouling transparent coating in marine environment, raw materials of which include film-forming material, curing agent and bacteriostatic functional factor; the film-forming material is water-based epoxy modified organic silicon resin, the curing agent is silane coupling agent (molecular weight is 221.4), and the bacteriostatic functional factor is carboxylated graphene oxide (molecular weight is 12.01).

[0008] In the present application, carboxylated graphene oxide is used as a bacteriostatic functional factor, the presence of carboxyl makes the surface of graphene oxide electronegative, and the surface of bacteria is also negatively charged, so the sample surface with negative charge can inhibit bacterial adhesion through electrostatic repulsion, and a higher level of active oxygen can destroy the bacterial membrane and cause the death of bacteria; on this basis, the water-based organic silicon resin high-temperature coating is cured at low temperature by using silane coupling agent, so that it has low surface energy (dynamic antifouling) and portable carboxyl functional groups to play a role in inhibiting bacteria and other microorganisms (static antifouling), and a pollution-free antibacterial low-surface-energy antifouling coating is prepared by combining the two functions, which has excellent antifouling effect in static and dynamic conditions.

[0009] Preferably, the epoxy value of the water-based epoxy modified organic silicon resin is 0.02-0.08, the solid content is 50±1%, and the viscosity cp≤600mpa·s (test conditions are 25℃ 1#12rpm NDJ-8S).

[0010] Preferably, the mass ratio of the water-based epoxy modified organic silicon resin, the silane coupling agent and the carboxylated graphene oxide is 20:1:0.001.

[0011] The second purpose of the present application is to provide a preparation method of the above-mentioned water-based organic corrosion-resistant antifouling transparent coating in marine environment, which comprises the following steps:

[0012] S1. The water-based epoxy modified organic silicon resin, the silane coupling agent and the carboxylated graphene oxide are weighed and proportioned;

[0013] S2. The carboxylated graphene oxide and the silane coupling agent weighed in S1 are uniformly mixed and placed in an ultrasonic oscillator for uniform dispersion, and after the dispersion is completed, the mixture is used as a modified curing agent for standby;

[0014] S3. The waterborne epoxy-modified silicone resin is mechanically stirred with the modified curing agent, mixed uniformly, and then sprayed for operation, and cured at room temperature (15-40 DEG C) to form a coating film.

[0015] Preferably, the uniform dispersion is achieved by placing the carboxylated graphene oxide in a container containing a silane coupling agent, ultrasonic oscillation frequency of 30-80 Hz, and oscillation time of 1-10 hours, to uniformly disperse the carboxylated graphene oxide in the silane coupling agent.

[0016] Preferably, in step S3, the mechanical stirring parameters are as follows: stirring speed of 200-800 r / min, and reaction temperature of 15-40 DEG C. If the reaction temperature is too low, the silane coupling reaction is not complete; if the temperature is too high, the reaction is too fast, and the mixed solution begins to form reaction coagulum, affecting the subsequent coating, i.e., too high or too low temperature will result in poor film forming effect and affect the film forming performance.

[0017] Preferably, in step S3, the room temperature curing time is 7 days.

[0018] The third object of the present application is to provide the application of the above-mentioned waterborne organic corrosion-resistant and antifouling transparent coating in the field of marine engineering and shipbuilding. Specifically, it is sprayed on the observation window of underwater detection equipment to improve the antifouling and microbial anti-adhesion performance, and improve the reliability and comprehensive performance of the equipment.

[0019] The present application has the following advantages:

[0020] The present application uses waterborne epoxy-modified silicone resin as the film-forming material, and successfully synthesizes a waterborne antifouling coating through simple ultrasonic oscillation and mechanical stirring. The synthesized coating has excellent antifouling and corrosion resistance in seawater and sulfur-reducing bacteria solution, and has excellent hydrophobicity.

[0021] The key of the present application is to use graphene oxide with specific functional groups (carboxyl groups) to make the coating have good antibacterial performance, thereby obtaining good static antifouling performance. On the premise of antibacterial and corrosion resistance, the coating also has hydrophobic properties, so that the coating film can achieve good antifouling performance in static and dynamic states. Compared with previous studies, the coating meets the environmental protection requirements of the times, and does not use traditional sterilizing agents to achieve the purpose of eliminating surface attachments. During service, it can be said to have zero pollution.

[0022] The present application enriches the system of waterborne antifouling organic coating materials, has the advantages of simplicity, wide applicability, etc., can effectively enhance the antifouling and microbial anti-adhesion performance of the observation window of underwater detection equipment, greatly improve the reliability and long-term performance of underwater observation equipment, ensure the stable operation of the equipment in extreme underwater environment, and has great application potential in the field of marine engineering and shipbuilding. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 Schematic diagram of the preparation of the water-based organic corrosion-resistant antifouling transparent coating of Example 1.

[0024] Figure 2 Scanning electron microscope observation diagram of the water-based organic corrosion-resistant antifouling transparent coating prepared in Example 1.

[0025] Figure 3 Comparison diagram of polarization curves of the water-based organic corrosion-resistant antifouling transparent coating prepared in Example 1 and the solidified film coating of the carboxyl graphene oxide without adding a curing agent in a 3.5wt% NaCl solution, respectively marked as COOH-GO@KH550 and KH550.

[0026] Figure 4 Water contact angle (three positions) of the water-based organic corrosion-resistant antifouling transparent coating prepared in Example 1.

[0027] Figure 5 Comparison diagram of the coating matrix prepared in Example 1 and the coating added with carboxyl graphene oxide immersed in a sulfate-reducing bacteria solution for 10 days.

[0028] Figure 6 Comparison diagram of the antibacterial effect of the coating prepared in Comparative Example 1 using different types of graphene oxide. Figure 7 Comparison diagram of the mixing effect of the raw materials mixed in different orders in Comparative Example 2.

[0029] Figure 8 Comparison diagram of the appearance of the coating prepared in Comparative Example 3 at different reaction temperatures. DETAILED DESCRIPTION

[0030] The present application is further described below in conjunction with the accompanying drawings and specific examples.

[0031] Example 1

[0032] A water-based organic corrosion-resistant antifouling transparent coating in a marine environment, the preparation process thereof is shown in Figure 1 and is prepared according to the following steps:

[0033] S1. The ingredients are prepared according to the mass ratio of m (water-based epoxy modified silicone resin) : m (silane coupling agent) : m (carboxylated graphene oxide) 20:1:0.001, and at the same time, the reference ingredients are prepared according to the mass ratio of m (water-based epoxy modified silicone resin) : m (silane coupling agent) 20:1; the water-based epoxy modified silicone resin used is SH9607, and the silane coupling agent used is KH550;

[0034] S2. The carboxylated graphene oxide is uniformly mixed with the silane coupling agent. Specifically, the carboxylated graphene oxide is placed in a container containing the silane coupling agent, and is subjected to ultrasonic treatment in an ultrasonic oscillator. The ultrasonic oscillation frequency is 40 Hz, and the oscillation time is 1.5 hours. The carboxylated graphene oxide is uniformly dispersed in the silane coupling agent, and is used as a modified curing agent.

[0035] S3. The waterborne epoxy-modified silicone resin is mechanically stirred with the modified curing agent in step S2. The stirring speed is 400 r / min, the reaction temperature is 25°C, and the stirring time is 5 min. After uniform mixing, the mixture is brushed on the surface of a metal substrate and is cured at room temperature for 7 days.

[0036] The waterborne organic corrosion-resistant and antifouling transparent coating prepared in Example 1 is subjected to performance testing. The performance testing methods are as follows:

[0037] 1. Film morphology observation: The film morphology of the coating is observed under a scanning electron microscope.

[0038] 2. Corrosion performance testing: Potentiodynamic polarization testing is performed on an electrochemical workstation. The sample size is 10 x 10 x 1 mm.

[0039] 3. Sulfate-reducing bacteria antifouling morphology observation: The macroscopic morphology of the coating surface after 10 days of immersion is captured using a digital camera. The sample size is 10 x 10 x 1 mm.

[0040] The performance testing results are as follows:

[0041] Figure 2 The scanning electron microscope observation of the waterborne organic corrosion-resistant and antifouling transparent coating shows that individual sheet-like carboxylated graphene oxide is exposed on the coating surface and is well embedded in the coating, indicating that the carboxylated graphene oxide has good compatibility with other components of the coating.

[0042] Figure 3 The polarization curve of the waterborne organic corrosion-resistant and antifouling transparent coating and the coating cured without adding carboxylated graphene oxide (reference group) is shown in Table 1. It can be seen that the coating containing carboxylated graphene oxide has better corrosion resistance than the coating without carboxylated graphene oxide.

[0043] Table 1

[0044]

[0045] Figure 4 The water contact angle of the waterborne organic corrosion-resistant and antifouling transparent coating (three positions) is greater than 90°, indicating that the coating has good hydrophobicity. Therefore, the coating has good dynamic antifouling performance under the action of water shear force.

[0046] Figure 5 The contrast chart of the water-based organic corrosion-resistant antifouling transparent coating and the coating matrix immersed in the sulfate-reducing bacteria solution for 10 days can be obtained. With the presence of the coating, excellent antifouling effect is achieved, and the coating shows good static antifouling performance at this time.

[0047] Comparative Example 1

[0048] In this comparative example, different raw materials are used for coating preparation compared with Example 1. The specific materials and results are as follows:

[0049] Group Material difference compared with Example 1 Results 1 Hydroxyl graphene oxide (different functional groups) Bacteriostatic performance is not as good as carboxyl graphene oxide 2 Graphene oxide (not carboxylated) Bacteriostatic performance is not as good as carboxyl graphene oxide 3 Other resins (specifically water-based polyurethane resin) Anticorrosion performance is not as good as water-based silicone resin 4 Other silane coupling agents (specifically kh570) Film forming effect of kh570 is not as good as kh550

[0050] Specifically, for the test of different types of graphene oxide, the coating prepared without adding graphene oxide is used as a control. Graphene oxide, carboxyl graphene oxide and hydroxyl graphene oxide are added to the coating under the same conditions. The prepared coating is immersed in sulfate-reducing bacteria for 10 days to observe their antibacterial performance. Through microscope observation, the bacteria emitting green fluorescence are more, the brighter the fluorescence, the worse the antibacterial effect. The results are shown in Figure 6 It can be seen that the carboxyl graphene oxide coating has the best antibacterial performance, and the surface has almost no sulfate-reducing bacteria attached.

[0051] Comparative Example 2

[0052] In this comparative example, three raw materials are tested in different mixing orders, as follows:

[0053] a. Three kinds of simultaneous mixing;

[0054] b. The silane coupling agent is mixed with carboxyl graphene oxide, and then mixed with the water-based emulsion (resin) for reaction; c. Carboxyl graphene oxide is mixed with the water-based emulsion, and then mixed with the silane coupling agent for reaction;

[0055] d. The silane coupling agent is mixed with the water-based emulsion, and then mixed with carboxyl graphene oxide for reaction.

[0056] The above four kinds of mixed samples are placed in 5 ml glass bottles, as shown in Figure 7 It can be seen that only the mixed solution obtained by the mixing order of b. carboxyl graphene oxide is uniformly distributed in the mixed solution, and there is no most precipitation or agglomeration.

[0057] Comparative Example 3

[0058] In this comparative example, the reaction temperature beyond the preferred range is tested for coating preparation compared with Example 1. The specific parameter settings and results are as follows:

[0059]

[0060] Note: The appearance of the prepared coating layers of the two groups is as shown in Figure 8 It can be seen that obvious defects exist in both.

[0061] The specific embodiments are only an explanation of the present application, and are not a limitation of the present application. Any change made by those skilled in the art after reading the specification of the present application will be protected by the patent law as long as it is within the scope of the claims of the present application.

Claims

1. A waterborne organic anticorrosive antifouling transparent coating in marine environment, characterized in that: The raw materials include a film-forming material, a curing agent and a bacteriostatic functional factor; the film-forming material is a waterborne epoxy-modified organic silicon resin, the curing agent is silane coupling agent KH550, and the bacteriostatic functional factor is carboxylated graphene oxide; the waterborne epoxy-modified organic silicon resin has an epoxy value of 0.02-0.08, a solid content of 50±1%, and a viscosity of ≤600 mpa·s; and the mass ratio of the waterborne epoxy-modified organic silicon resin, the silane coupling agent and the carboxylated graphene oxide is 20:1:0.

001. The waterborne organic corrosion-resistant and antifouling transparent coating in the marine environment is prepared by the following steps: S1. Measuring and weighing the waterborne epoxy-modified organic silicon resin, the silane coupling agent and the carboxylated graphene oxide in a metered ratio; S2. Mixing the carboxylated graphene oxide and the silane coupling agent weighed in S1 uniformly, placing them in an ultrasonic oscillator for uniform dispersion, and using the mixture as a modified curing agent after the dispersion is completed; S3. Mechanically stirring the waterborne epoxy-modified organic silicon resin and the modified curing agent prepared in S2, the parameters of the mechanical stirring being a stirring speed of 200-800 r / min and a reaction temperature of 15-40 DEG C; after uniform mixing, performing a spraying operation, and curing at room temperature to form a coating film.

2. The method for preparing the water-based organic corrosion-resistant and antifouling transparent coating for marine environments as described in claim 1, characterized in that: The steps include: S1. Measuring and weighing the waterborne epoxy-modified organic silicon resin, the silane coupling agent and the carboxylated graphene oxide in a metered ratio; S2. Mixing the carboxylated graphene oxide and the silane coupling agent weighed in S1 uniformly, placing them in an ultrasonic oscillator for uniform dispersion, and using the mixture as a modified curing agent after the dispersion is completed; S3. Mechanically stirring the waterborne epoxy-modified organic silicon resin and the modified curing agent prepared in S2, the parameters of the mechanical stirring being a stirring speed of 200-800 r / min and a reaction temperature of 15-40 DEG C; after uniform mixing, performing a spraying operation, and curing at room temperature to form a coating film.

3. The method of claim 2, wherein the method is characterized by: In step S2, the uniform dispersion is placing the carboxylated graphene oxide in a container containing the silane coupling agent, ultrasonically oscillating at a frequency of 30-80 Hz for 1-10 hours to uniformly disperse the carboxylated graphene oxide in the silane coupling agent.

4. The method of claim 2, wherein the method is characterized by: In step S3, the room-temperature curing time is 7 days.

5. Use of the waterborne organic anticorrosive and antifouling transparent coating in marine environment according to claim 1 in the field of marine and ocean engineering, characterized in that, The application method is spraying the coating on the observation window of underwater exploration equipment.

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