Condensation-resistant anticorrosive coating, method for preparing the same, and use thereof

Abstract

This invention relates to the field of corrosion protection, specifically to a condensation-resistant anti-corrosion coating, its preparation method, and its application. The condensation-resistant anti-corrosion coating of this invention comprises component A and component B. Component A, by weight, includes: 0.3-10 parts graphene, 5-30 parts tetrafunctional epoxy resin, 30-65 parts filler, 2-20 parts dispersant, and 10-50 parts solvent; component B, by weight, includes: 20-60 parts curing agent and 20-80 parts solvent; the mass ratio of component A to component B is 2-15:1. The coating formed by the condensation-resistant anti-corrosion coating of this invention has the characteristics of strong density and high cross-linking density, good chemical corrosion resistance under condensation conditions, and high adhesion, exhibiting excellent overall performance.

Description

Technical Field

[0001] This invention relates to the field of corrosion protection, specifically to a condensation-resistant anti-corrosion coating, its preparation method, and its application. Background Technology

[0002] In areas such as long-distance natural gas pipelines, chemical cold-insulation pipelines, and chemical pipeline pressure-reducing valves, significant temperature differences exist between the inside and outside of the pipeline, causing air to condense and accumulate on the outside. The coating on the pipeline's outer surface is constantly immersed in condensation. The condensate, along with dissolved acids, alkalis, and organic matter, reduces coating adhesion, ultimately leading to coating aging and failure, which is detrimental to the safe operation of the pipeline. Existing condensation corrosion prevention technologies mainly focus on increasing the water contact angle on the coating surface to create a superhydrophobic surface that prevents condensation adsorption and deposition, thereby improving the pipeline metal's resistance to condensation corrosion. CN111808514B discloses an anti-condensation corrosion coating that, by introducing polyhydroxy fluorosilicone modified polyurethane resin and hydrophobically modified wollastonite powder, increases the water contact angle on the coating surface to over 110°, improving its hydrophobic effect. However, the hydrophobic effect of the resin coating is closely related to the integrity of the coating surface; once the coating is damaged or worn, condensation will continuously accumulate, leading to corrosion. Summary of the Invention

[0003] To overcome the problems of existing anti-corrosion coatings being unable to be applied under condensation conditions, having insufficient chemical corrosion resistance, poor adhesion under condensation conditions, and being prone to bubbling and peeling, this invention provides a condensation-resistant anti-corrosion coating, its preparation method, and its application. The coating formed by the condensation-resistant anti-corrosion coating of this invention has the characteristics of strong density and high cross-linking density, good chemical corrosion resistance and high adhesion under condensation conditions, and excellent comprehensive performance. Moreover, the condensation-resistant anti-corrosion coating of this invention can be applied and formed in high humidity environments.

[0004] Unlike existing technologies that modify coatings by making them hydrophobic, this invention focuses on improving the density of the coating. It improves the coating's impermeability by increasing the crosslinking density and introducing sheet materials (such as graphene), thereby achieving resistance to condensation corrosion.

[0005] To achieve the above objectives, a first aspect of the present invention provides a condensation-resistant anti-corrosion coating, the coating comprising component A and component B. By weight, component A includes: 0.3-10 parts graphene, 5-30 parts tetrafunctional epoxy resin, 30-65 parts filler, 2-20 parts dispersant, and 10-50 parts solvent. By weight, component B comprises: 20-60 parts curing agent and 20-80 parts solvent; The mass ratio of component A to component B is 2-15:1.

[0006] A second aspect of the present invention provides a method for preparing the anti-condensation and anti-corrosion coating of the present invention, the method comprising: mixing the components of the coating.

[0007] A third aspect of the present invention provides a condensation-resistant anti-corrosion coating, wherein the condensation-resistant anti-corrosion coating is obtained by spraying, roller coating or dip coating after mixing component A and component B of the condensation-resistant anti-corrosion coating of the present invention.

[0008] The fourth aspect of the present invention provides an application of the anti-condensation anti-corrosion coating or anti-condensation coating of the present invention in anti-condensation anti-corrosion of metal and concrete substrates.

[0009] Through the above technical solution, the anti-condensation anti-corrosion coating of the present invention has the characteristics of strong density and high cross-linking density. It has the advantages of good chemical corrosion resistance and high adhesion under condensation conditions, and has excellent comprehensive performance. Moreover, the anti-condensation anti-corrosion coating of the present invention can be applied to form a coating in a high humidity environment, which solves the technical problem that traditional liquid coatings are not resistant to chemical corrosion under condensation immersion. This makes the coating formed by the coating exhibit excellent acid / alkali corrosion resistance, non-bubbling and non-peeling characteristics under long-term immersion in liquid (1500h).

[0010] Meanwhile, the anti-condensation anti-corrosion coating of the present invention has advantages such as good brushing performance in high humidity conditions (no bubbling, no peeling, no dripping at 350μm) and simple construction process (both spraying and brushing are possible). The resulting coating ensures good toughness while improving the density of the coating, and does not crack or peel off on irregularly shaped substrates; and the adhesion between the coating and the substrate is improved.

[0011] The anti-condensation and anti-corrosion coating of this invention can meet the anti-corrosion application needs of high-condensation areas such as the exterior of chemical cold insulation pipelines, the pressure reducing valve area of ​​natural gas long-distance pipelines, and the transportation pipelines of offshore drilling platforms. Detailed Implementation

[0012] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0013] The first aspect of the present invention provides a condensation-resistant anti-corrosion coating, which includes component A and component B. By weight, component A includes: 0.3-10 parts of graphene, 5-30 parts of tetrafunctional epoxy resin, 30-65 parts of filler, 2-20 parts of dispersant, and 10-50 parts of solvent. By weight, component B comprises: 20-60 parts curing agent and 20-80 parts solvent; the mass ratio of component A to component B is 2-15:1. The anti-condensation anti-corrosion coating of the present invention forms a coating with advantages such as strong density, high cross-linking density, good chemical corrosion resistance under condensation conditions, and high adhesion. Furthermore, the anti-condensation anti-corrosion coating of the present invention can be applied and formed in high humidity environments.

[0014] According to a preferred embodiment of the present invention, the graphene content in component A of the anti-condensation and anti-corrosion coating is 0.5-3 parts by weight.

[0015] According to a preferred embodiment of the present invention, the tetrafunctional epoxy resin in component A of the anti-condensation and anti-corrosion coating is 10-30 parts by weight.

[0016] According to a preferred embodiment of the present invention, the filler content in component A of the anti-condensation and anti-corrosion coating is 30-55 parts by weight.

[0017] According to a preferred embodiment of the present invention, the dispersant in component A of the anti-condensation and anti-corrosion coating is 3-10 parts by weight.

[0018] According to a preferred embodiment of the present invention, the solvent in component A of the anti-condensation and anti-corrosion coating is 15-40 parts by weight.

[0019] According to a preferred embodiment of the present invention, the mass ratio of component A to component B is 3-10:1.

[0020] In this invention, the epoxy value of the tetrafunctional epoxy resin can be selected from a wide range. According to a preferred embodiment of this invention, the epoxy value is 0.65-0.95.

[0021] In this invention, the tetrafunctional epoxy resin is selected from tetraglycidylamine type epoxy resin, and according to a preferred embodiment of the invention, it is selected from tetrafunctional epoxy resin having the structural formula shown in formula (1). Equation (1), In formula (1), R1 is selected from NH, O, and C1-C5 alkylene groups; the range of types of R2, R3, R4, and R5 is relatively wide. According to a preferred embodiment of the present invention, R2, R3, R4, and R5 are each independently selected from H and C1-C6 alkyl groups, and more preferably from H, methyl, or ethyl groups.

[0022] In this invention, the alkylene group is a straight-chain alkylene group, and the alkyl group is a straight-chain or branched alkyl group.

[0023] According to a preferred embodiment of the present invention, the tetrafunctional epoxy resin is selected from one or more of N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenyl ether, N,N,N',N'-tetraglycidyl-3,3'-diethyl-4,4'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-3,3'-dimethyl-4,4'-diaminodiphenylmethane, and N,N,N',N'-tetraglycidyl-3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane.

[0024] In this invention, any curing agent that can chemically react with epoxy resin to form a network three-dimensional polymer is acceptable. The range of curing agents that can be selected is relatively wide. For example, it can be a phenolic amine or a cashew phenol modified curing agent. According to a preferred embodiment of this invention, the curing agent is selected from a cashew phenol modified curing agent.

[0025] In this invention, the hydrogen equivalent of the cashew phenol modified curing agent can be selected from a wide range, which is illustrative but does not limit the scope of the invention. According to a preferred embodiment of the invention, the hydrogen equivalent is 160-300.

[0026] In this invention, the range of types of cashew phenol modified curing agents is relatively wide. According to a preferred embodiment of this invention, the cashew phenol modified curing agent is selected from cashew phenol modified phenolic amine or cashew phenol modified phenolic amide.

[0027] In this invention, the carbon content in graphene can be selected from a wide range, which is illustrative but does not limit the scope of the invention. According to a preferred embodiment of the invention, the carbon content of graphene is 90wt%-99.5wt% by mass.

[0028] In this invention, the particle size of graphene can be selected from a wide range. According to a preferred embodiment of this invention, the median particle size of graphene is 5μm-20μm, for example, 6μm, 8μm, 10μm, 12μm, 15μm, 17μm, and 19μm. This invention extends the diffusion path of corrosive agents by introducing graphene, thereby improving the durability of coatings under long-term immersion in liquid and solving the technical problem that traditional liquid coatings are not resistant to chemical corrosion under condensation immersion.

[0029] According to a preferred embodiment of the present invention, the coating is fluorine-free.

[0030] In this invention, the range of filler types is relatively wide. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the filler is selected from one or more of aluminum tripolyphosphate, bentonite, talc, titanium dioxide, zinc oxide, barium sulfate, carbon black, mica powder, and calcium carbonate.

[0031] In this invention, the filler is selected from filler 1 and filler 2. According to a preferred embodiment of the invention, filler 1 is selected from one or more of aluminum tripolyphosphate, titanium dioxide, mica powder and calcium carbonate; filler 2 is selected from one or more of bentonite, talc, zinc oxide, barium sulfate and carbon black.

[0032] In this invention, the content of filler 1 and filler 2 in the total weight of inorganic filler can be selected within a wide range. According to a preferred embodiment of this invention, filler 1 accounts for 30-65 wt% of the total weight of inorganic filler, and filler 2 accounts for 35-70 wt% of the total weight of inorganic filler.

[0033] In this invention, a wide range of dispersants can be selected. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the dispersant is selected from one or more of BYK-163, BYK-2163, BYK-2164 and MOK-5032.

[0034] In this invention, the solvents in components A and B can be the same or different, and the range of solvents that can be selected is relatively wide. This is an illustrative example, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the solvents in components A and B are each independently selected from one or more of toluene, xylene, n-butyl acetate, propylene glycol methyl ether acetate, butanone, methyl isobutyl ketone, propylene glycol methyl ether, diethylene glycol ethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol butyl ether acetate, and ethyl acetate.

[0035] According to a preferred embodiment of the present invention, the solvents in components A and B are each a mixed solution of toluene, xylene, and n-butyl acetate. More preferably, the volume ratio of toluene, xylene, and n-butyl acetate is 1:1-2.3:0.8-1.

[0036] According to a specific embodiment of the present invention, in the mixed solution of component A, the volume ratio of toluene, xylene, and n-butyl acetate is 1:1 to 2.3:1.

[0037] According to a specific embodiment of the present invention, in the mixed solution of component B, the volume ratio of toluene, xylene, and n-butyl acetate is 1:1:0.8-1.

[0038] A second aspect of this invention provides a method for preparing the condensation-resistant anti-corrosion coating of this invention, the method comprising: mixing the components of the coating. The condensation-resistant anti-corrosion coating prepared by the method of this invention has advantages such as high density, high crosslinking density, good chemical corrosion resistance under condensation conditions, applicability in high humidity environments, and high adhesion.

[0039] According to a preferred embodiment of the present invention, the method for preparing the condensation-resistant anti-corrosion coating includes: (1) After mixing graphene, filler 1, dispersant and solvent, epoxy resin is added after the first shearing, ground and mixed with filler 2, and then sheared again to obtain component A; (2) After mixing the curing agent and solvent, the third shear is performed to obtain component B; (3) Mix component A and component B.

[0040] In this invention, the first shearing condition is not particularly limited; conventional shearing conditions in the art are sufficient. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the first shearing condition includes: a temperature of 30°C-50°C; a rotation speed of 800 rpm-1500 rpm; and a time that can be determined according to the actual situation, generally 10-60 minutes.

[0041] In this invention, the grinding conditions are not particularly limited; conventional grinding conditions in the art are sufficient. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the grinding conditions include: grinding to a fineness of ≤45μm, preferably ≤25μm. For example, a sand mill can be used for the grinding. Preferably, the grinding media of the sand mill is 1.5mm-3mm zirconium beads; the rotation speed is 500-850rpm; and the time can be determined according to the actual situation, generally 20-40min.

[0042] In this invention, the second shearing condition is not particularly limited; conventional shearing conditions in the art are sufficient. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the second shearing condition includes: a rotational speed of 600 rpm to 1000 rpm; and a time that can be determined according to the actual situation, generally 30 to 60 minutes.

[0043] In this invention, the third shearing condition is not particularly limited; conventional shearing conditions in the art are sufficient. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the second shearing condition includes: a rotational speed of 800 rpm to 1000 rpm; and a time that can be determined according to the actual situation, generally 10-30 minutes.

[0044] A third aspect of this invention provides a condensation-resistant anti-corrosion coating, which is obtained by spraying, roller coating, or dip coating after mixing components A and B of the condensation-resistant anti-corrosion coating described in this invention. The condensation-resistant anti-corrosion coating of this invention maintains good toughness while improving density, and exhibits excellent resistance to condensation immersion.

[0045] In this invention, the thickness of the anti-condensation and anti-corrosion coating can be selected from a wide range, which is illustrative but does not limit the scope of the invention. According to a preferred embodiment of the invention, the thickness is 80μm-300μm.

[0046] In this invention, the adhesion of the anti-condensation and anti-corrosion coating has a wide range of selectable values. According to a preferred embodiment of this invention, the adhesion of the coating is ≥8MPa, preferably 10-12 MPa.

[0047] The fourth aspect of the present invention provides an application of the anti-condensation anti-corrosion coating or anti-condensation coating of the present invention in anti-condensation anti-corrosion of metal and concrete substrates.

[0048] According to a preferred embodiment of the present invention, the anti-condensation anti-corrosion coating or anti-condensation anti-corrosion coating of the present invention is applied to chemical cold insulation pipelines, pressure reducing valves of natural gas long-distance pipelines, transportation pipelines of offshore drilling platforms, or concrete substrates for anti-condensation anti-corrosion.

[0049] In the context and embodiments of this invention, the moisture resistance of the anti-condensation anti-corrosion coating is tested using the continuous condensation method according to GB / T 13893-2008, the salt spray test is conducted according to GB / T1771-2007, the paint film adhesion test is conducted according to GB / T1720-1979, and the paint film is cleaned according to GB / T8923.1-2011 before coating.

[0050] To further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the scope of the claims of the present invention.

[0051] In the following examples, the epoxy resin (AG-80) has the chemical formula N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane.

[0052] In the following examples, the hydrogen equivalent of the curing agent cashew nut shell oil modified phenolic amide (LITE-3100) is 150; the hydrogen equivalent of the curing agent phenolic amine (Xingdongcheng Chemical, T-31) is 60.

[0053] In the following embodiments, the paint film is applied using a two-coat spraying process, with a 2-hour interval between the two sprays, and the paint film thickness is 250 μm.

[0054] Example 1 (1) Take 1.5 parts of graphene powder with a median particle size of 18 μm, wherein the carbon content of the graphene is 99.5 wt%, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 13 parts of mica powder, 3.5 parts of BYK-163 dispersant, and 15 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 25 parts of epoxy resin (AG-80, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane) with an epoxy value of 0.8, mechanically stir and transfer it to a sand mill, grind at 700 rpm for 30 min, grind until the fineness is ≤25 μm. Add 5 parts bentonite, 15 parts barium sulfate, 6 parts zinc oxide, and 9 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:2:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0055] (2) Take 45 parts of cashew phenol modified phenolic amide (LITE-3100) and 55 parts of solvent (a mixture of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:1), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0056] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 5:1.

[0057] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0058] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 12 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the coating's moisture resistance meets the application requirements of the C5 corrosive environment; after 1536 hours, no blistering, cracking, or peeling occurred. After a 3000-hour neutral salt spray test, corrosion marks were only found at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0059] Example 2 (1) Take 0.5 parts of graphene powder with a median particle size of 18 μm, wherein the carbon content in the graphene is 99.5 wt%, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 20 parts of mica powder, 3.5 parts of BYK-2164 dispersant, and 10 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:1.5:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 15 parts of epoxy resin (AG-80) with an epoxy value of 0.8, mechanically stir and transfer to a sand mill, grind at 700 rpm for 30 min, grind until the fineness is ≤25 μm. Add 3 parts bentonite, 15 parts barium sulfate, 10 parts zinc oxide, and 6 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:1.5:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0060] (2) Take 20 parts of cashew phenol modified phenolic amide (LITE-3100) and 80 parts of solvent (a mixed solvent of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:0.8), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0061] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 8:1.

[0062] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0063] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 8 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the coating's moisture resistance meets the application requirements of the C5 corrosive environment; after 1440 hours, no blistering, cracking, or peeling occurred. After a 2600-hour neutral salt spray test, corrosion marks were only found at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0064] Example 3 (1) Take 3 parts of graphene powder with a median particle size of 18 μm, wherein the carbon content of the graphene is 99.5 wt%, 2 parts of titanium dioxide, 1 part of aluminum tripolyphosphate, 7 parts of mica powder, 10 parts of BYK-2163 dispersant, and 25 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 30 parts of N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenyl ether with an epoxy value of 0.9, mechanically stir and transfer to a sand mill, grind at 700 rpm for 30 min, grind until the fineness is ≤25 μm. Add 3 parts bentonite, 7 parts barium sulfate, 10 parts zinc oxide, and 15 parts solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1) to the above mixture. Then add them to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 min to obtain component A.

[0065] (2) Take 60 parts of cashew phenol modified phenolic amide (LITE-3100) and 40 parts of solvent (a mixed solvent of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:1), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0066] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 3:1.

[0067] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0068] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 12 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the coating's moisture resistance meets the application requirements of the C5 corrosive environment; after 1680 hours, no blistering, cracking, or peeling occurred. After a 2950-hour neutral salt spray test, corrosion marks were only found at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0069] Example 4 (1) Take 10 parts of graphene powder with a median particle size of 18 μm, wherein the carbon content of the graphene is 99.5 wt%, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 13 parts of mica powder, 3.5 parts of BYK-163 dispersant, and 10 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 25 parts of epoxy resin (AG-80) with an epoxy value of 0.8, mechanically stir and transfer to a sand mill, grind at 700 rpm for 30 min, grind until the fineness is ≤25 μm. Add 5 parts bentonite, 15 parts barium sulfate, 6 parts zinc oxide, and 5.5 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:2:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0070] (2) Take 45 parts of cashew phenol modified phenolic amide (LITE-3100) and 55 parts of solvent (a mixture of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:1), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0071] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 5:1.

[0072] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0073] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 9 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the coating's moisture resistance meets the application requirements of the C5 corrosive environment; after 1000 hours, no blistering, cracking, or peeling occurred. After a 2200-hour neutral salt spray test, corrosion marks were only found at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0074] Example 5 (1) Take 1.5 parts of graphene powder with a median particle size of 18 μm, wherein the carbon content of the graphene is 99.5 wt%, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 13 parts of mica powder, 3.5 parts of BYK-163 dispersant, and 15 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 25 parts of epoxy resin (AG-80) with an epoxy value of 0.8, mechanically stir and transfer to a sand mill, grind at 700 rpm for 30 min, grind until the fineness is ≤25 μm. Add 5 parts bentonite, 15 parts barium sulfate, 6 parts zinc oxide, and 9 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:2:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0075] (2) Take 45 parts of cashew phenol modified phenolic amide (LITE-3100) and 55 parts of solvent (a mixture of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:1), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0076] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 12:1.

[0077] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0078] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 8 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the moisture resistance of the coating can meet the application requirements of the C5 corrosive environment; after 800 hours, no blistering, cracking, or peeling occurred. After 1850 hours of neutral salt spray testing, the coating only showed corrosion marks at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0079] Example 6 (1) Take 1.5 parts of graphene powder with a median particle size of 18 μm, wherein the carbon content of the graphene is 99.5 wt%, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 13 parts of mica powder, 3.5 parts of BYK-163 dispersant, and 15 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 25 parts of epoxy resin (AG-80) with an epoxy value of 0.8, mechanically stir and transfer to a sand mill, grind at 700 rpm for 30 min, grind until the fineness is ≤25 μm. Add 5 parts bentonite, 15 parts barium sulfate, 6 parts zinc oxide, and 9 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:2:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0080] (2) Take 45 parts of phenolic amine (Xingdongcheng Chemical, T-31) and 55 parts of solvent (a mixed solvent of toluene, xylene and n-butyl acetate, in a volume ratio of 1:1:1), mix them, and shear them at 1000 rpm for 15 min to obtain component B.

[0081] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 5:1.

[0082] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0083] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 8 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the coating's moisture resistance meets the application requirements of the C5 corrosive environment. After 720 hours, no blistering, cracking, or peeling occurred. After an 1820-hour neutral salt spray test, corrosion marks were only found at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0084] Example 7 (1) Take 1.5 parts of graphene powder with a median particle size of 18 μm, wherein the carbon content of the graphene is 99.5 wt%, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 13 parts of mica powder, 3.5 parts of BYK-163 dispersant, and 15 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 25 parts of epoxy resin (AG-80) with an epoxy value of 0.8, mechanically stir and transfer to a sand mill, grind at 400 rpm for 20 min, grind until the fineness is ≤40 μm. Add 5 parts bentonite, 15 parts barium sulfate, 6 parts zinc oxide, and 9 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:2:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0085] (2) Take 45 parts of cashew phenol modified phenolic amide (LITE-3100) and 55 parts of solvent (a mixture of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:1), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0086] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 5:1.

[0087] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0088] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 8 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the coating's moisture resistance meets the application requirements of the C5 corrosive environment. After 720 hours, no blistering, cracking, or peeling occurred. After an 1800-hour neutral salt spray test, corrosion marks were only found at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0089] Example 8 The implementation method is the same as in Example 1, except that N,N,N',N'-tetraglycidyl-3,3'-diethyl-4,4'-diaminodiphenylmethane is replaced with an equal number of N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and the other conditions are the same as in Example 1.

[0090] Example 9 The implementation method is the same as in Example 1, except that N,N,N',N'-tetraglycidyl-3,3'-dimethyl-4,4'-diaminodiphenylmethane is replaced with an equal number of N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and the other conditions are the same as in Example 1.

[0091] Comparative Example 1 The implementation method is the same as in Example 1, except that an equal number of bifunctional epoxy resins, bisphenol A type epoxy resin (E-51) are used to replace epoxy resin (AG-80), and the other conditions are the same as in Example 1.

[0092] The adhesion of the obtained coating was 8 MPa. After 400 hours of continuous condensation testing, no blistering, cracking, or peeling occurred in the coating obtained by spraying. After 1800 hours of neutral salt spray testing, corrosion marks were only found at the scribing lines, and the corrosion did not spread to the sides.

[0093] Comparative Example 2 (1) Take 1.5 parts of carbon black with a median particle size of 18 μm, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 13 parts of mica powder, 3.5 parts of BYK-163, and 15 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 25 parts of epoxy resin (AG-80) with an epoxy value of 0.8, mechanically stir and then transfer to a sand mill, grind at 700 rpm for 30 min, until the fineness is ≤25 μm. Add 5 parts bentonite, 15 parts barium sulfate, 6 parts zinc oxide, and 9 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:2:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0094] (2) Take 45 parts of cashew shell oil modified phenolic amide (LITE-3100) and 55 parts of solvent (a mixture of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:1), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0095] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 5:1.

[0096] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0097] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 10 MPa; the coating obtained by spraying the coating passed a 720-hour continuous condensation test, indicating that the coating's moisture resistance meets the application requirements of the C5 corrosive environment; after 600 hours, no blistering, cracking, or peeling occurred. After a 400-hour neutral salt spray test, corrosion marks were only found at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0098] Comparative Example 3 (1) Take 1.5 parts of graphene powder with a median particle size of 18 μm, 5 parts of titanium dioxide, 2 parts of aluminum tripolyphosphate, 13 parts of mica powder, 3.5 parts of BYK-163, and 15 parts of solvent (toluene, xylene, and n-butyl acetate mixed solvent, volume ratio 1:2:1), add them to a high-speed shear mixer, adjust the speed to 1200 rpm, shear and disperse for 60 min, control the shear temperature to 40℃, until all solids are evenly dispersed and no stratification occurs. Add 25 parts of bifunctional epoxy resin with an epoxy value of 0.8 and bisphenol A type epoxy resin (NPEL-128, Nanya Resin), mechanically stir and transfer to a sand mill, grind at 700 rpm for 30 min, grind until the fineness is ≤25 μm. Add 5 parts bentonite, 15 parts barium sulfate, 6 parts zinc oxide, and 9 parts solvent (a mixture of toluene, xylene, and n-butyl acetate in a volume ratio of 1:2:1) to the above mixture. Then add these components sequentially to a high-speed shear mixer and shear and disperse them at 1000 rpm for 30 minutes to obtain component A.

[0099] (2) Take 45 parts of cashew shell oil modified phenolic amide (LITE-3100) and 55 parts of solvent (a mixture of toluene, xylene and n-butyl acetate in a volume ratio of 1:1:1), mix them and shear at 1000 rpm for 15 min to obtain component B.

[0100] (3) Mix component A obtained in step (1) with component B obtained in step (2) at a mass ratio of 5:1.

[0101] The prepared anti-condensation and anti-corrosion coating was sprayed onto a pre-treated carbon steel substrate using a spraying method (spraying pressure 0.6 MPa).

[0102] The aforementioned testing standards were used for testing: the adhesion of the obtained coating was 11 MPa; after 500 hours of continuous condensation testing, no blistering, cracking, or peeling occurred in the coating obtained by spraying the coating. After 1800 hours of neutral salt spray testing, the coating only showed corrosion marks at the scribing lines, and the corrosion did not spread to both sides, meeting the requirements for neutral salt spray resistance.

[0103] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A condensation-resistant anti-corrosion coating, characterized in that, The coating consists of component A and component B. By weight, component A includes: 0.3-10 parts graphene, 5-30 parts tetrafunctional epoxy resin, 30-65 parts filler, 2-20 parts dispersant, and 10-50 parts solvent. By weight, component B comprises: 20-60 parts curing agent and 20-80 parts solvent; The mass ratio of component A to component B is 2-15:

1.

2. The anti-condensation and anti-corrosion coating according to claim 1, wherein, Component A comprises, by weight: 0.5-3 parts graphene; and / or 10-30 parts of tetrafunctional epoxy resin; and / or 30-55 parts of filler; and / or 3-10 parts of dispersant; and / or Solvent 15-40 parts; and / or The mass ratio of component A to component B is 3-10:

1.

3. The anti-condensation and anti-corrosion coating according to claim 1 or 2, wherein, In component A, the epoxy value of the tetrafunctional epoxy resin is 0.65-0.95; and / or The tetrafunctional epoxy resin is selected from tetraglycidylamine type epoxy resins. Preferably, the tetrafunctional epoxy resin has the structural formula shown in formula (1). Equation (1), In formula (1), R1 is selected from NH, O, C1-C5 alkylene groups; and / or R2, R3, R4, and R5 are each independently selected from H and C1-C6 alkyl groups, preferably H, methyl, or ethyl; More preferably, the tetrafunctional epoxy resin is selected from one or more of N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenyl ether, N,N,N',N'-tetraglycidyl-3,3'-diethyl-4,4'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-3,3'-dimethyl-4,4'-diaminodiphenylmethane, and N,N,N',N'-tetraglycidyl-3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane.

4. The anti-condensation and anti-corrosion coating according to any one of claims 1-3, wherein, The graphene contains 90wt%-99.5wt% carbon by mass; and / or The median particle size of the graphene is 5 μm-20 μm; and / or The curing agent is selected from cashew nut phenol modified curing agents, and more preferably the cashew nut phenol modified curing agent has a hydrogen equivalent of 160-300; Preferably, the cashew phenol-modified curing agent is selected from cashew phenol-modified phenolic amine and / or cashew phenol-modified phenolic amide; and / or The coating does not contain fluorine.

5. The anti-condensation and anti-corrosion coating according to any one of claims 1-4, wherein, The filler is selected from one or more of the following: aluminum tripolyphosphate, bentonite, talc, titanium dioxide, zinc oxide, barium sulfate, carbon black, mica powder, and calcium carbonate; The preferred packing material is selected from packing material 1 and packing material 2, wherein, Filler 1 is selected from one or more of aluminum tripolyphosphate, titanium dioxide, mica powder, and calcium carbonate; Filler 2 is selected from one or more of bentonite, talc, zinc oxide, barium sulfate, and carbon black; Preferably, packing 1 accounts for 30-65 wt% of the total weight of the packing, and packing 2 accounts for 35-70 wt% of the total weight of the packing; and / or The dispersant is selected from one or more of BYK-163, BYK-2163, BYK-2164 and MOK-5032.

6. The anti-condensation and anti-corrosion coating according to any one of claims 1-5, wherein, In components A and B, the solvents are each independently selected from one or more of toluene, xylene, n-butyl acetate, propylene glycol methyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol methyl ether, diethylene glycol ethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol butyl ether acetate, and ethyl acetate. Preferably, in components A and B, the solvent is a mixed solution of toluene, xylene, and n-butyl acetate. More preferably, the volume ratio of toluene, xylene, and n-butyl acetate is 1:1-2.3:0.8-1.

7. The method for preparing the anti-condensation and anti-corrosion coating according to any one of claims 1-6, characterized in that, The method includes: mixing the components of the coating; Preferably, the preparation method includes: (1) After mixing graphene, filler 1, dispersant and solvent, epoxy resin is added after the first shearing, ground and mixed with filler 2, and then sheared again to obtain component A; (2) After mixing the curing agent and solvent, the third shear is performed to obtain component B; (3) Mix component A and component B.

8. The preparation method according to claim 7, wherein, The first shearing conditions include: a rotation speed of 800 rpm to 1500 rpm; a time of 10 to 60 minutes; and / or Grinding conditions include: grinding to a fineness ≤45μm, preferably ≤25μm; rotation speed of 500-850 rpm; time of 20-40 min; and / or The second shearing conditions include: a rotation speed of 600 rpm to 1000 rpm; a time of 30 min to 60 min; and / or The third shearing conditions include: a rotation speed of 800 rpm to 1000 rpm and a time of 10 min to 30 min.

9. A condensation-resistant and corrosion-resistant coating, characterized in that, The anti-condensation and anti-corrosion coating is obtained by spraying, rolling or dipping after mixing components A and B of the anti-condensation and anti-corrosion coating according to any one of claims 1-6. Preferably, the thickness of the anti-condensation and anti-corrosion coating is 80μm-300μm; and / or The adhesion of the coating is ≥8MPa, preferably 10-12MPa.

10. The application of the anti-condensation anti-corrosion coating according to any one of claims 1-6 or the anti-condensation anti-corrosion coating according to claim 9 in anti-condensation corrosion protection of metal and concrete substrates, preferably in the application of chemical cold insulation pipelines, pressure reducing valves of long-distance natural gas pipelines, transportation pipelines of offshore drilling platforms, and anti-condensation corrosion protection of concrete substrates.

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