A corrosion-resistant coating for the surface of metal components and its manufacturing method

Abstract

The invention discloses a corrosion-resistant coating for the surface of a metal component and a manufacturing method thereof. The corrosion-resistant coating comprises the following raw materials in parts by weight: 50-70 parts of bisphenol A epoxy resin, 15-20 parts of polyester polyurethane resin, 10-15 parts of polyether polyurethane resin, 2-15 parts of modified materials, 20-30 parts of corrosion-resistant fillers, 1-5 parts of cross-linking agents, 1-5 parts of coupling agents, 1-5 parts of antioxidants, and 15-20 parts of solvents. The present invention utilizes the modified materials to modify the bisphenol A epoxy resin, improves the mechanical properties of the bisphenol A epoxy resin, and then utilizes the cross-linking network formed between the bisphenol A epoxy resin and the polyester polyurethane resin, and the bisphenol A epoxy resin, the polyester polyurethane resin and the polyether polyurethane resin are blended to effectively improve the corrosion resistance of the coating, and at the same time, the coupling agent and the antioxidant are added to effectively improve the adhesion and aging resistance of the coating, and extend the service life of the coating.

Description

Technical Field

[0001] The invention relates to the technical field of metal surface coatings, and in particular to a corrosion-resistant coating for the surface of a metal component and a manufacturing method thereof. Background Art

[0002] With the widespread application of a large number of metal materials in various industries, the anti-corrosion of metal materials has been paid more and more attention. According to incomplete statistics from developed countries, the economic losses caused by corrosion each year account for about 1%-4% of the national economic output value. Especially in high temperature and strong corrosive working environment, the corrosion of metal materials is more serious. The corrosion of metal materials not only causes economic losses, but also brings safety hazards to the safety of the structure. After long-term use, metal materials will encounter various environmental challenges.

[0003] Metal surface coatings serve as a protective layer on the metal surface and can effectively protect the metal surface. However, in actual use, the surface coatings often corrode after being corroded, making it impossible to effectively protect the metal surface. Summary of the invention

[0004] In view of this, the purpose of the present invention is to overcome the problems existing in the prior art and provide a corrosion-resistant coating for the surface of metal components. The coating utilizes a modified material to modify bisphenol A epoxy resin to improve the mechanical properties of bisphenol A epoxy resin, and then utilizes the cross-linking network formed between bisphenol A epoxy resin and polyester polyurethane resin. The bisphenol A epoxy resin, polyester polyurethane resin and polyether polyurethane resin are blended to effectively improve the corrosion resistance of the coating. At the same time, a coupling agent and an antioxidant are added to effectively improve the adhesion and aging resistance of the coating and extend the service life of the coating.

[0005] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0006] A corrosion-resistant coating for the surface of a metal component comprises the following raw materials in parts by weight: 50-70 parts of bisphenol A epoxy resin, 15-20 parts of polyester polyurethane resin, 10-15 parts of polyether polyurethane resin, 2-15 parts of modified material, 20-30 parts of corrosion-resistant filler, 1-5 parts of crosslinking agent, 1-5 parts of coupling agent, 1-5 parts of antioxidant, and 15-20 parts of solvent. The polyester polyurethane resin has good chemical corrosion resistance, and the polyether polyurethane resin has good wear resistance. The polyester polyurethane resin and the polyether polyurethane resin are blended with the bisphenol A epoxy resin to modify the bisphenol A epoxy resin to form a composite material, thereby improving the corrosion resistance and wear resistance of the coating. In addition, the hydroxyl group in the polyester polyurethane resin can react with the epoxy group in the bisphenol A epoxy resin to form a crosslinking network, so that the coating has better corrosion resistance.

[0007] Preferably, the modified material is a mixture of flaky aluminum powder and porous aluminum microspheres in a weight ratio of 1-1.2:1. Aluminum powder has excellent corrosion resistance. Adding aluminum powder to epoxy resin can effectively protect bisphenol A epoxy resin, improve the corrosion resistance of the coating, and extend the service life; at the same time, flaky aluminum powder has good filling performance. The flaky aluminum powder and porous aluminum microspheres are mixed and used. The porous aluminum microspheres can avoid the stacking and agglomeration of flaky aluminum powder. The flaky structure of the flaky aluminum powder and the porous structure of the porous aluminum microspheres can fill the pores in the epoxy resin, thereby improving the mechanical properties and wear resistance of the epoxy resin.

[0008] Preferably, the corrosion-resistant filler is glass fiber and / or silica microbeads. Adding glass fiber to epoxy resin can form a physical shield, effectively slowing down or hindering the erosion of metal components by corrosive media; the interface bonding force between glass fiber and epoxy resin is strong, which can effectively prevent the corrosive media from penetrating into the interior of the resin, thereby improving the corrosion resistance of the coating; glass fiber also has a high hardness, which can increase the surface hardness of the epoxy resin, effectively improving the wear resistance and corrosion resistance of the coating. Adding silica microbeads to epoxy resin can form an interface barrier effect, effectively slowing down or hindering the erosion of metal components by corrosive media; the microbead structure of silica microbeads can fill the internal micropores and defects of epoxy resin, thereby enhancing the compactness of epoxy resin, effectively preventing the corrosive media from penetrating into the interior of the resin, and effectively improving the corrosion resistance of the coating; silica microbeads also have good chemical stability, which can effectively resist the erosion of chemical corrosive media, thereby improving the corrosion resistance of the coating.

[0009] Preferably, the crosslinking agent is a mixture of TDI and PDI in a weight ratio of 1:1-1.5. The isocyanate groups in TDI and PDI can react with the hydroxyl groups in the polyester polyurethane resin to form urea bonds, and can react with the epoxy functional groups in the bisphenol A epoxy resin to form ether bonds or ester bonds, so that the bisphenol A epoxy resin and the polyester polyurethane resin form a crosslinking network. The two are mixed and used, which has higher crosslinking ability, so that the crosslinking density of the crosslinking network formed by the bisphenol A epoxy resin and the polyester polyurethane resin is higher, and the coating has better corrosion resistance.

[0010] Preferably, the coupling agent is selected from one or more of KH-570, KH-560 and KH-550. KH-570 has good adhesion and film-forming properties, and can effectively improve the interfacial bonding strength between epoxy resin and glass fiber and silica microbead inorganic filler; KH-560 can improve the compatibility between epoxy resin and glass fiber and silica microbead inorganic filler, thereby improving the mechanical properties and weather resistance of the coating; the amino functional group in KH-550 can react with the epoxy group in the epoxy resin to form a hydrogen bond or a covalent bond, thereby improving the interfacial bonding strength between the epoxy resin and the glass fiber and silica microbead inorganic filler.

[0011] Preferably, the antioxidant is selected from one or more of 2,6-di-tert-butyl-4-methylphenol, 3,5-di-tert-butyl-4-hydroxyphenyl tetraol and 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate.

[0012] Preferably, the solvent is a mixture of ethyl acetate and butyl acetate in a weight ratio of 1:1-1.5.

[0013] Another object of the present invention is to provide a method for manufacturing a corrosion-resistant coating for the surface of a metal component. The manufacturing method is simple to operate, has low production cost, high production efficiency, and can be used for industrial mass production.

[0014] The above-mentioned object of the present invention is achieved by the following technical means:

[0015] A method for manufacturing the above-mentioned corrosion-resistant coating for the surface of a metal component comprises the following steps:

[0016] (1) adding bisphenol A epoxy resin, polyester polyurethane resin, polyether polyurethane resin and crosslinking agent into a mixer according to weight parts, and mixing them evenly under high pressure to obtain a mixture A for standby use;

[0017] (2) adding the modified material to the mixture A and mixing them evenly to obtain a mixture B for later use;

[0018] (3) Add corrosion-resistant filler, coupling agent, antioxidant and solvent to mixture B in sequence and mix well to obtain corrosion-resistant coating.

[0019] Preferably, in step (1), the mixing time is 1-2 h, the mixing rate is 800-1000 rpm / min, and the pressure is 2-4 MPa.

[0020] Preferably, in step (2), the mixing time is 1-2 hours, and the mixing rate is 500-800 rpm / min; in step (3), the mixing time is 2-6 hours, and the mixing rate is 1000-1500 rpm / min.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention blends polyester polyurethane resin and polyether polyurethane resin with bisphenol A epoxy resin to modify the bisphenol A epoxy resin to form a composite material, thereby improving the corrosion resistance and wear resistance of the coating;

[0023] 2. The present invention utilizes the hydroxyl groups in the polyester polyurethane resin to react with the epoxy groups in the bisphenol A epoxy resin, so that a cross-linked network is formed between the bisphenol A epoxy resin and the polyester polyurethane resin, so that the coating has better corrosion resistance;

[0024] 3. The present invention effectively improves the adhesion and aging resistance of the coating and prolongs the service life of the coating by adding corrosion-resistant fillers, coupling agents and antioxidants. DETAILED DESCRIPTION

[0025] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the embodiments are not intended to limit the present invention.

[0026] Example 1

[0027] A corrosion-resistant coating for the surface of metal components, characterized in that it comprises the following raw materials in parts by weight: 50 parts of bisphenol A epoxy resin, 15 parts of polyester polyurethane resin, 10 parts of polyether polyurethane resin, 7 parts of modified material, 20 parts of corrosion-resistant filler, 2 parts of cross-linking agent, 2 parts of coupling agent, 3 parts of antioxidant, and 15 parts of solvent.

[0028] The modified material is a mixture of flaky aluminum powder and porous aluminum microspheres in a weight ratio of 1:1, the corrosion-resistant filler is glass fiber, the coupling agent is KH-570, the antioxidant is 2,6-di-tert-butyl-4-methylphenol, and the solvent is a mixture of ethyl acetate and butyl acetate in a weight ratio of 1:1.

[0029] The corrosion-resistant coating is prepared by the following steps:

[0030] (1) adding bisphenol A epoxy resin, polyester polyurethane resin, polyether polyurethane resin and crosslinking agent into a mixer according to weight parts, and mixing them evenly under high pressure to obtain a mixture A for standby use;

[0031] (2) adding the modified material to the mixture A and mixing them evenly to obtain a mixture B for later use;

[0032] (3) Add corrosion-resistant filler, coupling agent, antioxidant and solvent to mixture B in sequence and mix well to obtain corrosion-resistant coating.

[0033] In step (1), the mixing time is 1.5 h, the mixing rate is 900 rpm / min, and the pressure is 2.5 MPa; in step (2), the mixing time is 1.5 h, the mixing rate is 600 rpm / min; in step (3), the mixing time is 3 h, and the mixing rate is 1200 rpm / min.

[0034] Example 2

[0035] A corrosion-resistant coating for the surface of metal components, characterized in that it comprises the following raw materials in parts by weight: 65 parts of bisphenol A epoxy resin, 18 parts of polyester polyurethane resin, 12 parts of polyether polyurethane resin, 10 parts of modified material, 26 parts of corrosion-resistant filler, 4 parts of cross-linking agent, 3 parts of coupling agent, 2 parts of antioxidant, and 18 parts of solvent.

[0036] The modified material is a mixture of flaky aluminum powder and porous aluminum microspheres in a weight ratio of 1.1:1, the corrosion-resistant filler is silica gel microspheres, the coupling agent is KH-560, the antioxidant is 3,5-di-tert-butyl-4-hydroxyphenyl tetraol ester, and the solvent is a mixture of ethyl acetate and butyl acetate in a weight ratio of 1:1.3.

[0037] The corrosion-resistant coating is prepared by the following steps:

[0038] (1) adding bisphenol A epoxy resin, polyester polyurethane resin, polyether polyurethane resin and crosslinking agent into a mixer according to weight parts, and mixing them evenly under high pressure to obtain a mixture A for standby use;

[0039] (2) adding the modified material to the mixture A and mixing them evenly to obtain a mixture B for later use;

[0040] (3) Add corrosion-resistant filler, coupling agent, antioxidant and solvent to mixture B in sequence and mix well to obtain corrosion-resistant coating.

[0041] In step (1), the mixing time is 2 hours, the mixing rate is 1000 rpm / min, and the pressure is 3 MPa; in step (2), the mixing time is 1.2 hours, the mixing rate is 700 rpm / min; in step (3), the mixing time is 5 hours, and the mixing rate is 1400 rpm / min.

[0042] Example 3

[0043] A corrosion-resistant coating for the surface of metal components, characterized in that it comprises the following raw materials in parts by weight: 70 parts of bisphenol A epoxy resin, 20 parts of polyester polyurethane resin, 15 parts of polyether polyurethane resin, 15 parts of modified material, 28 parts of corrosion-resistant filler, 5 parts of cross-linking agent, 5 parts of coupling agent, 5 parts of antioxidant, and 20 parts of solvent.

[0044] The modified material is a mixture of flaky aluminum powder and porous aluminum microspheres in a weight ratio of 1.2:1, the corrosion-resistant filler is glass fiber, the coupling agent is KH-550, the antioxidant is 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate octadecyl, and the solvent is a mixture of ethyl acetate and butyl acetate in a weight ratio of 1:1.5.

[0045] The corrosion-resistant coating is prepared by the following steps:

[0046] (1) adding bisphenol A epoxy resin, polyester polyurethane resin, polyether polyurethane resin and crosslinking agent into a mixer according to weight parts, and mixing them evenly under high pressure to obtain a mixture A for standby use;

[0047] (2) adding the modified material to the mixture A and mixing them evenly to obtain a mixture B for later use;

[0048] (3) Add corrosion-resistant filler, coupling agent, antioxidant and solvent to mixture B in sequence and mix well to obtain corrosion-resistant coating.

[0049] In step (1), the mixing time is 2 hours, the mixing rate is 1000 rpm / min, and the pressure is 4 MPa; in step (2), the mixing time is 2 hours, the mixing rate is 800 rpm / min; in step (3), the mixing time is 6 hours, and the mixing rate is 1500 rpm / min.

[0050] Comparative Example 1

[0051] Compared with Example 1, Comparative Example 1 does not add polyester polyurethane resin to the coating, and the other components and manufacturing steps are the same.

[0052] Comparative Example 2

[0053] Compared with Example 1, Comparative Example 2 does not add modifying material to the coating, and the remaining components and manufacturing steps are the same.

[0054] Comparative Example 3

[0055] Compared with Example 1, in Comparative Example 3, no corrosion-resistant filler is added to the coating, and the remaining components and manufacturing steps are the same.

[0056] The coatings prepared in Examples 1-3 and Comparative Examples 1-3 were tested, and the test results are as follows:

[0057]

[0058] From the above results, it can be seen that the corrosion-resistant coatings prepared in Examples 1-3 of the present invention are prepared by modifying bisphenol A epoxy resin using a modifying material to improve the mechanical properties of bisphenol A epoxy resin, and then forming a cross-linked network between bisphenol A epoxy resin and polyester polyurethane resin. Bisphenol A epoxy resin, polyester polyurethane resin and polyether polyurethane resin are blended to effectively improve the corrosion resistance of the coating. At the same time, coupling agents and antioxidants are added to effectively improve the adhesion and aging resistance of the coating, thereby extending the service life of the coating.

[0059] The technical solutions provided by the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the embodiments of the present invention. The description of the above embodiments is only applicable to help understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, according to the embodiments of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A corrosion-resistant coating for the surface of a metal component, characterized in that: The invention comprises the following raw materials in parts by weight: 50-70 parts of bisphenol A epoxy resin, 15-20 parts of polyester polyurethane resin, 10-15 parts of polyether polyurethane resin, 2-15 parts of modified material, 20-30 parts of corrosion-resistant filler, 1-5 parts of crosslinking agent, 1-5 parts of coupling agent, 1-5 parts of antioxidant, and 15-20 parts of solvent; the hydroxyl group in the polyester polyurethane resin can react with the bisphenol A type The epoxy groups in the epoxy resin react to form a cross-linked network; the modified material is a mixture of flaky aluminum powder and porous aluminum microspheres in a weight ratio of 1-1.2:1; the corrosion-resistant filler is glass fiber and / or silica microspheres; the cross-linking agent is a mixture of TDI and PDI in a weight ratio of 1:1-1.

5.

2. The corrosion-resistant coating for the surface of a metal component according to claim 1, characterized in that: The coupling agent is selected from one or more of KH-570, KH-560 and KH-550.

3. The corrosion-resistant coating for the surface of a metal component according to claim 1, characterized in that: The antioxidant is selected from one or more of 2,6-di-tert-butyl-4-methylphenol, 3,5-di-tert-butyl-4-hydroxyphenyl tetraol ester and 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate octadecyl.

4. The corrosion-resistant coating for the surface of a metal component according to claim 1, characterized in that: The solvent is a mixture of ethyl acetate and butyl acetate in a weight ratio of 1:1-1.

5.

5. A method for manufacturing a corrosion-resistant coating for a metal component surface according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Add bisphenol A epoxy resin, polyester polyurethane resin, polyether polyurethane resin and cross-linking agent into a mixer according to weight parts, mix them evenly under high pressure conditions to obtain a mixture A, which is set aside; (2) Add the modified material to the mixture A and mix well to obtain a mixture B for later use; (3) Add corrosion-resistant filler, coupling agent, antioxidant and solvent to mixture B in sequence and mix them evenly to obtain a corrosion-resistant coating.

6. The method for manufacturing a corrosion-resistant coating for a metal component surface according to claim 5, characterized in that: In step (1), the mixing time is 1-2 h and the pressure is 2-4 MPa.

7. The method for manufacturing a corrosion-resistant coating for a metal component surface according to claim 5, characterized in that: In step (2), the mixing time is 1-2 hours; in step (3), the mixing time is 2-6 hours.

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