Special polyurea composite coating for corrosion prevention of marine instruments and equipment

Abstract

The utility model is applicable to the technical field of corrosion prevention of marine instruments, and provides a special polyurea composite coating for corrosion prevention of marine instruments and equipment, which comprises a base material, a polyurea coating b is arranged on one side of the base material close to the instruments and equipment, and fiber gridding cloth is arranged on one side of the polyurea coating b far away from the base material. A polyurea coating a with filler is arranged outside the fiber gridding cloth, a blocking layer formed by silver alginate is opened by taking the most common corrosion ion Cl <-> in a marine environment as a signal molecule, PDMS in the filler can effectively migrate, and particles can be aggregated together by virtue of the viscosity of the PDMS to form a super-smooth surface with a micro-nano hierarchical structure. According to the special polyurea composite coating for corrosion prevention of the marine instrument equipment, provided by the scheme, the chloride ion permeation resistance and the microbial adhesion resistance of the marine instrument equipment in the service period are improved, and the service life is prolonged.

Description

Technical Field

[0001] The utility model belongs to the technical field of marine instrument anti-corrosion, and in particular relates to a polyurea composite coating specially used for the anti-corrosion of marine instruments and equipment. Background Art

[0002] As the proportion of marine economy in the national economy increases, various marine instruments and equipment are put into use. The corrosion and microbial contamination faced by marine instruments and equipment are very serious, which not only reduces the service life of marine instruments, but also affects the functionality of instruments and equipment.

[0003] Polyurea coatings have better mechanical properties and adhesion than other coatings due to their internal urea bonds and intermolecular forces, and have higher density, and have good application prospects in the field of corrosion protection. - As the most corrosive ion in seawater, the concentration in seawater reaches 19000ppm. Studies have shown that polyurea coatings have poor resistance to chloride ions. When polyurea coatings are used in marine environments for a long time, chloride ions will further penetrate into the substrate and cause corrosion. At the same time, polyurea is also easily attached to microorganisms without modification, thus further causing biofouling.

[0004] Based on the above situation, it is necessary to design a polyurea coating that can effectively block chloride ion penetration and microbial attachment while also ensuring adhesion to the substrate. Utility Model Content

[0005] The utility model provides a polyurea composite coating specially used for anti-corrosion of marine instruments and equipment, aiming to solve the problem that the coating currently used is difficult to effectively block the penetration of chloride ions and the attachment of microorganisms.

[0006] The utility model is realized in this way: a polyurea composite coating specially used for corrosion protection of marine instruments and equipment comprises: a substrate, a polyurea coating b is provided on the side of the substrate close to the instruments and equipment, a fiber mesh cloth is provided on the side of the polyurea coating b away from the substrate, and a polyurea coating a with filler is provided on the outside of the fiber mesh cloth.

[0007] Preferably, the coating thickness of the polyurea coating b is 500-1000 um, and the coating has good medium resistance through epoxy modification, while retaining good adhesion to the substrate.

[0008] Preferably, the fiber mesh cloth is one of polyester fiber mesh cloth, polypropylene fiber mesh cloth and polyacrylonitrile fiber mesh cloth, and has a thickness of 200 to 500 um.

[0009] Preferably, the filler is PDMS-loaded halloysite nanotubes.

[0010] Preferably, both ends of the halloysite nanotube are sealed with silver alginate.

[0011] Preferably, the coating thickness of the polyurea coating with filler is 1500-2000 um.

[0012] Compared with the related art, the polyurea composite coating for anti-corrosion of marine instruments and equipment provided by the utility model has the following beneficial effects:

[0013] Compared with the existing technology, this solution has the following advantages:

[0014] 1. Through the most common corrosive ion Cl in the marine environment - As a signal molecule, the blocking layer composed of silver alginate is opened, and the PDMS inside the filler can migrate effectively. With its own viscosity and the ability to aggregate particles together to form an ultra-slippery surface with a micro-nano hierarchical structure, it inhibits the attachment of microorganisms. At the same time, the generated AgCl can also play a certain antibacterial role. The two-pronged approach effectively inhibits the attachment of microorganisms on the polyurea surface.

[0015] 2. Corrosion ion C l - When penetrating into the external coating, it is consumed in large quantities. At the same time, the inorganic fillers in the external coating will also block the channels for the corrosive medium to enter by filling the vacancies. - It is difficult to penetrate into the internal epoxy-modified polyurea coating;

[0016] 3. The epoxy-modified polyurea coating on the side close to the substrate has good mechanical properties, media resistance and adhesion. It is overlapped with the outer functional polyurea coating through the fiber mesh cloth, which ensures the adhesion and strength of the composite polyurea coating system to the substrate. The composite coating improves the resistance of marine instruments and equipment to chloride ion penetration and microbial adhesion during service, and extends the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the cross-sectional structure of a polyurea composite coating specially used for anti-corrosion of marine instruments and equipment provided by the utility model;

[0018] Reference numerals: 1. polyurea coating a; 2. polyurea coating b; 3. substrate. DETAILED DESCRIPTION

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0020] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0021] The utility model provides a polyurea composite coating for anti-corrosion of marine instruments and equipment, such as Figure 1 As shown, the polyurea composite coating specially used for corrosion protection of marine instruments and equipment includes: a substrate 3, a polyurea coating b2 is provided on the side of the substrate 3 close to the instruments and equipment, the polyurea coating b2 is an epoxy-modified high-crosslinked polyurea coating, and a fiber mesh cloth is provided on the side of the epoxy-modified high-crosslinked polyurea coating b2 away from the substrate 3, and a polyurea coating a1 with filler is provided on the outside of the fiber mesh cloth.

[0022] In this application example, the preparation method of the composite coating is:

[0023] Step 1: Add the PDMS solution into a centrifuge tube, add a certain amount of halloysite nanotubes, and then add the PDMS solution, evacuate under negative pressure for 2 hours, and then centrifuge to remove excess PDMS and retain the precipitate to obtain PDMS halloysite nanotubes.

[0024] Step 2: Add the precipitate obtained in step 1 to the sodium alginate solution, stir with a magnetic stirrer for 10 minutes, then centrifuge for 3 to 5 minutes, wash the obtained precipitate with pure water, and then dry it in an oven for 3 minutes to obtain sodium alginate-coated PDMS halloysite nanotubes.

[0025] Step 3: Take a certain amount of sodium alginate-coated PDMS halloysite nanotubes obtained in step 2, add a certain amount of silver nitrate solution thereto, stir with a magnetic stirrer for 10 minutes, then centrifuge for 3 to 5 minutes, wash the resulting precipitate with pure water, and then put it in an oven to dry for 3 minutes to obtain a smart responsive filler system.

[0026] Step 4: Add the amine chain extender to the epoxy in a certain proportion, react at 65℃~100℃ for 2h to generate an amino-terminated epoxy adduct, which is used as component B and sprayed on the substrate surface of marine instruments and equipment with component A (isocyanate) in a volume ratio of 1:1.

[0027] Step 5: Before the polyurea layer 1 gels, embed the mesh cloth into it.

[0028] Step 6: Add filler to component B (the remaining components are composed of polyols and chain extenders) at a ratio of 50% to 60%, and spray component A (isocyanate) and component B on the surface of polyurea layer 1 at a volume ratio of 1:1 before the surface of polyurea layer 1 dries to obtain a composite coating.

[0029] In this embodiment, the epoxy-modified high cross-linked polyurea coating b2 introduces epoxy functional groups into the polyurea structure, which is essentially a reinforcement of the polyurea coating. A high cross-linking degree can be achieved by using a low molecular weight multi-functional chain extender, which essentially connects more polymer substances to form a network. By increasing the content of the cross-linking agent, more cross-linked structures can be formed during the reaction process, thereby increasing the cross-linking density. However, excessive use of cross-linking agents will lead to excessive hardness of the resin and reduce the overall performance.

[0030] In a further preferred embodiment of the present invention, the coating thickness of the epoxy-modified high-crosslinked polyurea coating b2 is 500-1000 um.

[0031] In this embodiment, the coating thickness of the epoxy-modified high-crosslinked polyurea coating b2 is set to meet the use requirements while avoiding waste to a large extent.

[0032] In a further preferred embodiment of the utility model, the fiber mesh cloth is one of polyester fiber mesh cloth, polypropylene fiber mesh cloth and polyacrylonitrile fiber mesh cloth, and has a thickness of 200-500um.

[0033] In this embodiment, the thickness of the fiber mesh cloth is set to meet the use requirements while avoiding waste to a large extent. The fiber mesh cloth has good flexibility and plasticity, can adapt to various complex shapes and structures, and provide sufficient support and reinforcement. During the coating preparation process, the fiber mesh cloth can be closely combined with the polyurea coating to form a composite coating structure, thereby improving the overall performance and stability of the coating.

[0034] Specifically, the fiber mesh cloth can enhance the tensile strength, compressive strength and impact resistance of the coating, improve the hardness and wear resistance of the coating, and at the same time, the fiber mesh cloth can also improve the toughness and ductility of the coating, making it less likely to crack or fall off when subjected to external forces;

[0035] In addition, this fiber mesh cloth also has good durability and stability, can maintain its performance and shape for a long time, and is not easily eroded and damaged by environmental factors. Therefore, this fiber mesh cloth has broad application prospects and value in practical applications;

[0036] It should be noted that the specific fiber mesh material and thickness should be selected and adjusted according to the actual application requirements and the properties of the substrate to achieve the best protection and support effect. At the same time, during the preparation and use process, attention should be paid to controlling the uniformity and density of the fiber mesh to ensure the stability and reliability of its performance.

[0037] In a further preferred embodiment of the present invention, the filler is a PDMS-loaded halloysite nanotube.

[0038] In this embodiment, the filler is a special material loaded with PDMS halloysite nanotubes, which has excellent physical and chemical properties and can provide good mechanical properties, thermal stability and electrical properties;

[0039] Specifically, PDMS halloysite nanotubes play a role in enhancing the performance of composite materials in fillers. Since halloysite nanotubes have the characteristics of high aspect ratio, high specific surface area and good thermal stability, they can effectively improve the mechanical properties, thermal stability and electrical properties of composite materials.

[0040] In a further preferred embodiment of the present invention, both ends of the halloysite nanotubes are sealed with silver alginate.

[0041] In this embodiment, both ends of the halloysite nanotubes are sealed with silver alginate, which can enhance the connection and interaction between the nanotubes and further improve the overall performance and stability of the composite material;

[0042] This filler is evenly dispersed in the polyurea coating when preparing it, forming a special composite coating structure that can provide better protection and support, making the substrate more durable and stable.

[0043] It should be noted that the specific filler material and preparation method should be selected and adjusted according to the actual application requirements and the properties of the substrate to achieve the best protection and support effect. At the same time, during the preparation and use process, attention should be paid to controlling the uniformity and density of the filler to ensure the stability and reliability of its performance.

[0044] In a further preferred embodiment of the present invention, the coating thickness of the polyurea coating a1 with filler is 1500-2000 um.

[0045] In this embodiment, the coating of this thickness can effectively resist erosion and damage from the external environment, such as water, oxygen, ultraviolet rays, etc., thereby extending the service life of the substrate. At the same time, the coating of this thickness can also provide good physical properties, such as hardness, wear resistance, impact resistance, etc., so that the substrate maintains stable performance during use;

[0046] In addition, the coating of this thickness is easy to construct and operate, and can meet the needs of large-scale production and application. Therefore, the coating of this thickness has broad application prospects and value in practical applications;

[0047] It should be noted that the specific coating thickness should be selected and adjusted according to the actual application requirements and the properties of the substrate to achieve the best protection and support effect. At the same time, during the preparation and use process, attention should be paid to controlling the uniformity and density of the coating to ensure the stability and reliability of its performance.

[0048] In summary, compared with related technologies, it has the following advantages:

[0049] The most common corrosive ion in the marine environment is Cl - As a signal molecule, the blocking layer composed of silver alginate is opened, and the PDMS inside the filler can migrate effectively. With its own viscosity and the ability to aggregate particles together to form an ultra-slippery surface with a micro-nano hierarchical structure, the adhesion of microorganisms is inhibited. At the same time, the generated AgCl can also play a certain antibacterial role. The two-pronged approach effectively inhibits the adhesion of microorganisms on the polyurea surface.

[0050] Corrosive ions Cl - When penetrating into the external coating, it is consumed in large quantities. At the same time, the inorganic fillers in the external coating will also block the channels for the corrosive medium to enter by filling the vacancies. - It is difficult to penetrate into the internal epoxy-modified polyurea coating;

[0051] The epoxy-modified polyurea coating on the side close to the substrate has good mechanical properties, media resistance and adhesion. It is overlapped with the outer functional polyurea coating through a fiber mesh cloth, ensuring the adhesion and strength of the overall composite polyurea coating system to the substrate. The composite coating improves the ability of marine instruments and equipment to resist chloride ion penetration and microbial adhesion during service, thereby extending their service life.

[0052] In the above-mentioned micro-nano hierarchical structure, if the coating is only filled with argon nanotubes (pure nanoscale filler), its surface cannot capture enough air, while PDMS can aggregate many nanostructured particles together to form a micro-nano hierarchical structure by virtue of its viscosity. This structure enables the coating surface to effectively capture enough air formed in micro-nano structures of different levels (forming an air cover layer), which is a necessary condition for forming a super-slippery surface.

[0053] In addition to being a binder, PDMS also acts as a lubricant. It has the advantages of high stability, low surface energy, strong chemical inertness, and little influence by ambient temperature. It can form a stable lubricating oil layer on the substrate surface.

[0054] The above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit the protection scope of the utility model. Obviously, the described embodiments are only some embodiments of the utility model, rather than all embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model. Although the utility model has been described in detail with reference to the above embodiments, ordinary technicians in this field can still combine, add, delete or make other adjustments to the features in the various embodiments of the utility model according to the circumstances without conflict, without making creative work, so as to obtain different other technical solutions that do not deviate from the concept of the utility model in essence, and these technical solutions also belong to the scope of protection of the utility model.

Claims

1. A polyurea composite coating specially used for anti-corrosion of marine instruments and equipment, characterized in that: include: A substrate, wherein a layer of polyurea coating b is provided on the side of the substrate close to the instrument and equipment, a fiber mesh cloth is provided on the side of the polyurea coating b away from the substrate, and a layer of polyurea coating a with filler for corrosion protection of marine instruments and equipment is provided on the outside of the fiber mesh cloth.

2. The polyurea composite coating for anti-corrosion of marine instruments and equipment as claimed in claim 1, characterized in that: The coating thickness of the polyurea coating b is 500-1000 um.

3. The polyurea composite coating for anti-corrosion of marine instruments and equipment as claimed in claim 1, characterized in that: The fiber mesh cloth is one of polyester fiber mesh cloth, polypropylene fiber mesh cloth and polyacrylonitrile fiber mesh cloth, and has a thickness of 200-500um.

4. The polyurea composite coating for anti-corrosion of marine instruments and equipment as claimed in claim 1, characterized in that: The filler is a PDMS-loaded halloysite nanotube.

5. The polyurea composite coating for anti-corrosion of marine instruments and equipment as claimed in claim 4, characterized in that: Both ends of the halloysite nanotube are sealed with silver alginate.

6. The polyurea composite coating for anti-corrosion of marine instruments and equipment as claimed in claim 1, characterized in that: The coating thickness of the polyurea coating a with filler is 1500-2000 um.

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