A kind of anticorrosion and fireproof sandwich structure coating for nuclear island and its preparation method and application

Abstract

The present invention relates to the technical field of fire-retardant coatings, and proposes an anti-corrosion and fire-retardant sandwich structure coating for a nuclear island, and a preparation method and application thereof. An anti-corrosion and fire-retardant sandwich structure coating for a nuclear island comprises, from bottom to top, an anti-corrosion primer, a fire-retardant coating, and a radiation-resistant topcoat. The anti-corrosion primer comprises the following component raw materials in parts by weight: 30 to 50 parts of epoxy resin, 40 to 60 parts of zinc powder, 10 to 20 parts of graphene, 3 to 5 parts of pigment, 0.5 to 1.5 parts of defoaming agent, 1 to 2 parts of leveling agent, 5 to 10 parts of curing agent, and 10 to 20 parts of water. The graphene comprises modified graphene oxide, and the modified graphene oxide is obtained by modifying graphene oxide with a modifier I, and the modifier I is an epoxy carbazole compound. Through the above technical scheme, the problem of low anti-corrosion and fire-retardant performance of the coating for the nuclear island in the related technology is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of fire retardant coatings, and in particular to an anticorrosion and fireproof sandwich structure coating for a nuclear island, and a preparation method and application thereof. Background Art

[0002] Nuclear power coatings are widely used in the steel structures, concrete, equipment pipelines and other parts of nuclear islands and conventional islands of nuclear power plants. Due to the special working environment and strict safety standards of nuclear power plants, higher requirements are placed on the radiation resistance, wear resistance, corrosion resistance, decontamination and fire resistance of nuclear power coatings. Therefore, it is necessary to develop a coating for nuclear islands with corrosion and fire resistance. Summary of the invention

[0003] The present invention provides an anti-corrosion and fireproof sandwich structure coating for a nuclear island and a preparation method and application thereof, which solves the problem of low anti-corrosion and fireproof performance of the coating for the nuclear island in the related art.

[0004] The technical scheme of the present invention is as follows: The present invention proposes an anti-corrosion and fireproof sandwich structure coating for a nuclear island, which includes an anti-corrosion primer, a fireproof coating, and a radiation-resistant topcoat from bottom to top. The anti-corrosion primer includes the following component raw materials in parts by weight: 30 to 50 parts of epoxy resin, 40 to 60 parts of zinc powder, 10 to 20 parts of graphene, 3 to 5 parts of pigment, 0.5 to 1.5 parts of defoaming agent, 1 to 2 parts of leveling agent, 5 to 10 parts of curing agent, and 10 to 20 parts of water. The graphene includes modified graphene oxide, and the modified graphene oxide is obtained by modifying graphene oxide with a modifier I, and the modifier I is an epoxy carbazole compound.

[0005] As a further technical solution, the epoxy resin is bisphenol A epoxy resin.

[0006] As a further technical solution, the fire retardant coating is an intumescent fire retardant coating.

[0007] As a further technical solution, the radiation-resistant topcoat is an acrylic polyurethane topcoat.

[0008] As a further technical solution, the raw material of the modified graphene oxide includes modifier I and graphene oxide in a mass ratio of 1 to 2:10.

[0009] As a further technical solution, the epoxycarbazole compound includes one or two of 4-epoxypropyleneoxycarbazole and 5-(oxiranylmethoxy)-2,3,4,9-tetrahydrocarbazole.

[0010] As a further technical solution, the preparation method of the modified graphene oxide comprises the following steps: dispersing the modifier I in a solution, adding graphene oxide, filtering and drying after modification to obtain the modified graphene oxide.

[0011] As a further technical solution, the solution is dimethyl sulfoxide.

[0012] As a further technical solution, the mass ratio of the solution to the graphene oxide is 10:1.

[0013] As a further technical solution, the modification time is 6 hours.

[0014] As a further technical solution, the graphene also includes nitrogen-doped graphene, and the mass ratio of the modified graphene oxide to the nitrogen-doped graphene is 5:3-4.

[0015] In the present invention, modified graphene oxide and nitrogen-doped graphene are added simultaneously to exert the synergistic effect of the two, construct a more complex and dense barrier network, and further enhance the anti-corrosion and fire-proof properties of the sandwich structure coating.

[0016] As a further technical solution, the nitrogen-doped graphene is modified nitrogen-doped graphene, and the modified nitrogen-doped graphene is obtained by modifying nitrogen-doped graphene with a modifier II, and the modifier II is a benzoheterocyclic formamidine compound.

[0017] As a further technical solution, the raw materials of the modified nitrogen-doped graphene include modifier II and nitrogen-doped graphene in a mass ratio of 2 to 3:20, and the benzoheterocyclic formamidine compound includes one or two of N-hydroxy-1,3-benzodioxolane-5-formamidine and 4-benzo[1,3]dioxolane-5-yl-piperazine-1-formamidine.

[0018] In the present invention, benzoheterocyclic formamidine compounds are used to modify nitrogen-doped graphene to enhance the bonding strength among nitrogen-doped graphene, bisphenol A epoxy resin and matrix material. The strong bonding force can prevent the coating from falling off, ensure that the anti-corrosion primer can continuously and effectively play the role of anti-corrosion and fire prevention, and further enhance the anti-corrosion and fire prevention performance of the sandwich structure coating.

[0019] As a further technical solution, the preparation method of the modified nitrogen-doped graphene includes the following steps: dispersing the modifier II in a solution, adding nitrogen-doped graphene, filtering and drying after modification to obtain the modified nitrogen-doped graphene.

[0020] As a further technical solution, the solution is N,N-dimethylformamide.

[0021] As a further technical solution, the mass ratio of the solution to the nitrogen-doped graphene is 10:1.

[0022] As a further technical solution, the modification time is 4 hours.

[0023] As a further technical solution, the pigment includes one or more of zinc chrome yellow, zinc phosphate, and zinc molybdate.

[0024] As a further technical solution, the defoaming agent is a silicone defoaming agent.

[0025] As a further technical solution, the leveling agent includes one or more of BYK-333, BYK-332, and BYK-3560.

[0026] As a further technical solution, the curing agent includes one or more of ethylenediamine, meta-phenylenediamine, and phthalic anhydride.

[0027] The present invention also provides a method for preparing a corrosion-resistant and fire-resistant sandwich structure coating for a nuclear island, comprising the following steps:

[0028] S1. Weigh graphene, pigment, defoamer and water, mix them evenly, add epoxy resin, grind, add leveling agent and curing agent, and sieve to obtain anticorrosive primer;

[0029] S2. Spray the anticorrosive primer, fire retardant coating and radiation resistant topcoat on the surface of the substrate from bottom to top in sequence to form an anticorrosive primer layer, a fire retardant coating layer and a radiation resistant topcoat layer, thereby obtaining an anticorrosive and fire retardant sandwich structure coating.

[0030] As a further technical solution, the grinding fineness is 40 μm, and the sieve mesh size is 250 meshes.

[0031] As a further technical solution, the thickness of the anticorrosive primer layer is 80 μm, the thickness of the fire retardant coating layer is 3 mm, and the thickness of the radiation resistant topcoat layer is 60 μm.

[0032] The present invention also proposes the use of the anti-corrosion and fire-proof sandwich structure coating obtained by the preparation method of the anti-corrosion and fire-proof sandwich structure coating for a nuclear island in the nuclear power radiation zone of a nuclear island.

[0033] The working principle and beneficial effects of the present invention are:

[0034] In the present invention, an anticorrosive primer, a fireproof coating, and a radiation-resistant topcoat are sequentially arranged from bottom to top to prepare an anticorrosive and fireproof sandwich structure coating, which forms a complete system of anticorrosion and fireproofing, and effectively improves the comprehensive performance of the coating. The present invention uses epoxy resin as a base material, adds modified graphene oxide to prepare an anticorrosive primer, avoids the agglomeration of graphene oxide, enhances the dispersibility of graphene oxide and the bonding strength with epoxy resin, forms a denser and firmer primer coating on the surface of the substrate, and enhances the anticorrosion and fireproofing properties of the sandwich structure coating. DETAILED DESCRIPTION

[0035] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the following examples and comparative examples:

[0037] Fire retardant coating: intumescent fire retardant coating, model number is jhk-0002;

[0038] Radiation-resistant topcoat: acrylic polyurethane topcoat, model QUIW-2410;

[0039] Graphene oxide: oxygen content 50wt%, average thickness 2nm, diameter 5μm;

[0040] Bisphenol A epoxy resin: model E-44;

[0041] Zinc powder: average particle size is 200 mesh;

[0042] Nitrogen-doped graphene: nitrogen content 7wt%, average thickness 5nm;

[0043] Silicone defoamer: model is BK-L099, manufacturer is Guangzhou Duomeiduo New Materials Co., Ltd.

[0044] Example 1

[0045] The preparation method of modified graphene oxide comprises the following steps: dispersing 2 parts of 4-epoxypropyleneoxycarbazole in 200 parts of dimethyl sulfoxide, adding 20 parts of graphene oxide, modifying for 6 hours, filtering and drying to obtain modified graphene oxide;

[0046] A method for preparing an anticorrosion and fireproof sandwich structure coating for a nuclear island comprises the following steps:

[0047] S1. Weigh 40 parts of zinc powder, 10 parts of modified graphene oxide, 3 parts of zinc chrome yellow, 0.5 parts of silicone defoamer, and 10 parts of water, mix them evenly, add 30 parts of bisphenol A epoxy resin, grind to a fineness of 40 μm, add 1 part of BYK-333 and 5 parts of ethylenediamine, and pass through a 250-mesh sieve to obtain an anticorrosive primer;

[0048] S2. Spray the anti-corrosion primer, fire retardant coating and radiation resistant topcoat on the surface of the substrate from bottom to top in sequence to form an anti-corrosion primer layer, a fire retardant coating layer and a radiation resistant topcoat layer with thicknesses of 80 μm, 3 mm and 60 μm respectively, to obtain an anti-corrosion and fire retardant sandwich structure coating.

[0049] Example 2

[0050] The preparation method of modified graphene oxide comprises the following steps: dispersing 2 parts of 4-epoxypropyleneoxycarbazole in 200 parts of dimethyl sulfoxide, adding 20 parts of graphene oxide, modifying for 6 hours, filtering and drying to obtain modified graphene oxide;

[0051] A method for preparing an anticorrosion and fireproof sandwich structure coating for a nuclear island comprises the following steps:

[0052] S1. Weigh 50 parts of zinc powder, 15 parts of modified graphene oxide, 4 parts of zinc phosphate, 1 part of silicone defoamer, and 15 parts of water, mix them evenly, add 40 parts of bisphenol A epoxy resin, grind to a fineness of 40 μm, add 1.5 parts of BYK-333 and 8 parts of m-phenylenediamine, and pass through a 250-mesh sieve to obtain an anticorrosive primer;

[0053] S2. Spray the anti-corrosion primer, fire retardant coating and radiation resistant topcoat on the surface of the substrate from bottom to top in sequence to form an anti-corrosion primer layer, a fire retardant coating layer and a radiation resistant topcoat layer with thicknesses of 80 μm, 3 mm and 60 μm respectively, to obtain an anti-corrosion and fire retardant sandwich structure coating.

[0054] Example 3

[0055] The preparation method of modified graphene oxide comprises the following steps: dispersing 2 parts of 4-epoxypropyleneoxycarbazole in 200 parts of dimethyl sulfoxide, adding 20 parts of graphene oxide, modifying for 6 hours, filtering and drying to obtain modified graphene oxide;

[0056] A method for preparing an anticorrosion and fireproof sandwich structure coating for a nuclear island comprises the following steps:

[0057] S1, weigh 60 parts of zinc powder, 20 parts of modified graphene oxide, 5 parts of zinc molybdate, 1.5 parts of silicone defoamer, and 20 parts of water, mix them evenly, add 50 parts of bisphenol A epoxy resin, grind to a fineness of 40 μm, add 2 parts of BYK-333 and 10 parts of phthalic anhydride, and pass through a 250-mesh sieve to obtain an anticorrosive primer;

[0058] S2. Spray the anti-corrosion primer, fire retardant coating and radiation resistant topcoat on the surface of the substrate from bottom to top in sequence to form an anti-corrosion primer layer, a fire retardant coating layer and a radiation resistant topcoat layer with thicknesses of 80 μm, 3 mm and 60 μm respectively, to obtain an anti-corrosion and fire retardant sandwich structure coating.

[0059] Example 4

[0060] Compared with Example 1, the difference of Example 4 is that the added amount of 4-epoxypropyleneoxycarbazole is 4 parts.

[0061] Example 5

[0062] Compared with Example 4, Example 5 is different in that 4-epoxypropyleneoxycarbazole is replaced with an equal amount of 5-(oxiranylmethoxy)-2,3,4,9-tetrahydrocarbazole.

[0063] Example 6

[0064] Compared with Example 5, the difference of Example 6 is that the modified graphene oxide is completely replaced by modified graphene oxide and nitrogen-doped graphene in a mass ratio of 5:2.

[0065] Example 7

[0066] Compared with Example 6, the difference of Example 7 is that the modified graphene oxide is completely replaced by modified graphene oxide and nitrogen-doped graphene in a mass ratio of 5:3.

[0067] Example 8

[0068] Compared with Example 7, the difference of Example 8 is that the modified graphene oxide is completely replaced by modified graphene oxide and nitrogen-doped graphene in a mass ratio of 5:4.

[0069] Example 9

[0070] The preparation method of modified nitrogen-doped graphene comprises the following steps: weighing 2 parts of N-hydroxy-1,3-benzodioxolane-5-carboxamidine and dispersing them in 200 parts of N,N-dimethylformamide, adding 20 parts of nitrogen-doped graphene and modifying them for 4 hours, filtering and drying to obtain modified nitrogen-doped graphene;

[0071] Compared with Example 8, the difference of Example 9 is that the nitrogen-doped graphene is replaced by an equal amount of modified nitrogen-doped graphene obtained by the above preparation method.

[0072] Example 10

[0073] Compared with Example 9, the difference in Example 10 is that the added amount of N-hydroxy-1,3-benzodioxolane-5-carboxamidine is 3 parts.

[0074] Embodiment 11

[0075] Compared with Example 10, Example 11 is different in that N-hydroxy-1,3-benzodioxolane-5-carboximidamide is replaced with an equal amount of 4-benzo[1,3]dioxol-5-yl-piperazine-1-carboximidamide.

[0076] Comparative Example 1

[0077] Compared with Example 1, the difference in Comparative Example 1 is that the modified graphene oxide is replaced by an equal amount of graphene oxide.

[0078] Comparative Example 2

[0079] Compared with Example 5, the difference in Comparative Example 2 is that the modified graphene oxide is replaced by an equal amount of nitrogen-doped graphene.

[0080] The anticorrosive primers prepared in Examples 1 to 11 and Comparative Examples 1 to 2 were sprayed on the surface of the steel plate with a paint film thickness of 80 μm. The salt spray resistance of the samples was tested according to the test method specified in GB / T 1771-2007 "Determination of neutral salt spray resistance of paints and varnishes", and the time when bubbles, rust, cracking, peeling, etc. appeared in the anticorrosive primers was recorded.

[0081] The anti-corrosion and fire-proofing sandwich structure coatings prepared in Examples 1 to 11 and Comparative Examples 1 to 2 were sprayed on the surface of the steel plate to form an anti-corrosion primer layer, a fire-proof coating layer, and a radiation-resistant topcoat layer with thicknesses of 80 μm, 3 mm, and 60 μm, respectively. The fire resistance limit of the obtained anti-corrosion and fire-proofing sandwich structure coatings was tested according to the test method specified in GB 14907-2018 "Fire Retardant Coatings for Steel Structures".

[0082] The test results are shown in the following table:

[0083] Table 1 Performance test results of samples prepared in Examples 1 to 11 and Comparative Examples 1 to 2

[0084]

[0085] Compared with Comparative Example 1, Example 1 adds modified graphene oxide. As a result, the salt spray resistance and fire resistance of Example 1 are better than those of Comparative Example 1, indicating that when modified graphene oxide is added, the corrosion resistance and fire resistance of the coating can be improved.

[0086] Compared with Example 5 and Comparative Example 2, Examples 6 to 8 simultaneously added modified graphene oxide and nitrogen-doped graphene. As a result, the salt spray resistance and fire resistance of Examples 6 to 8 were better than those of Example 5 and Comparative Example 2, indicating that modified graphene oxide and nitrogen-doped graphene play a synergistic role and can further improve the corrosion resistance and fire resistance of the coating.

[0087] Compared with Example 8, Examples 9 to 11 added modified nitrogen-doped graphene. As a result, the salt spray resistance and fire resistance of Examples 9 to 11 were better than those of Example 8, indicating that when modified nitrogen-doped graphene was added, the obtained coating had better anti-corrosion and fire resistance.

[0088] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A corrosion-resistant and fire-resistant sandwich coating for a nuclear island, characterized in that: The invention comprises, from bottom to top, an anticorrosive primer, a fireproof coating, and a radiation-resistant topcoat. The anticorrosive primer comprises the following raw materials by weight: 30 to 50 parts of epoxy resin, 40 to 60 parts of zinc powder, 10 to 20 parts of graphene, 3 to 5 parts of pigment, 0.5 to 1.5 parts of defoamer, 1 to 2 parts of leveling agent, 5 to 10 parts of curing agent, and 10 to 20 parts of water. The graphene comprises modified graphene oxide, and the modified graphene oxide is obtained by modifying graphene oxide with a modifier I, and the modifier I is an epoxy carbazole compound. The graphene further comprises nitrogen-doped graphene, and the mass ratio of the modified graphene oxide to the nitrogen-doped graphene is 5:3-4; The nitrogen-doped graphene is modified nitrogen-doped graphene, and the modified nitrogen-doped graphene is obtained by modifying nitrogen-doped graphene with a modifier II, and the modifier II is a benzoheterocyclic formamidine compound; The benzoheterocyclic carboxamidine compound includes one or two of N-hydroxy-1,3-benzodioxolane-5-carboxamidine and 4-benzo[1,3]dioxol-5-yl-piperazine-1-carboxamidine.

2. The anticorrosion and fireproof sandwich structure coating for a nuclear island according to claim 1, characterized in that: The raw materials of the modified graphene oxide include modifier I and graphene oxide in a mass ratio of 1 to 2:

10.

3. The anticorrosion and fireproof sandwich coating for a nuclear island according to claim 1, characterized in that: The epoxycarbazole compound includes one or two of 4-epoxypropyleneoxycarbazole and 5-(oxiranylmethoxy)-2,3,4,9-tetrahydrocarbazole.

4. The anticorrosion and fireproof sandwich coating for a nuclear island according to claim 1, characterized in that: The preparation method of the modified graphene oxide comprises the following steps: dispersing a modifier in a solution, adding graphene oxide, filtering and drying after modification, so as to obtain the modified graphene oxide.

5. The anticorrosion and fireproof sandwich structure coating for a nuclear island according to claim 1, characterized in that: The raw materials for modifying nitrogen-doped graphene include modifier II and nitrogen-doped graphene in a mass ratio of 2 to 3:

20.

6. The anticorrosion and fireproof sandwich structure coating for a nuclear island according to claim 1, characterized in that: It also includes at least one of the following technical features: The pigment includes one or more of zinc chrome yellow, zinc phosphate, and zinc molybdate; The defoamer is an organosilicon defoamer; The leveling agent includes one or more of BYK-333, BYK-332, and BYK-3560; The curing agent includes one or more of ethylenediamine, m-phenylenediamine and phthalic anhydride.

7. The method for preparing a corrosion-resistant and fire-resistant sandwich structure coating for a nuclear island according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Weigh graphene, zinc powder, pigment, defoamer and water, mix them evenly, add epoxy resin, grind, add leveling agent and curing agent, and sieve to obtain anticorrosive primer; S2. Spray the anticorrosive primer, fire retardant coating and radiation resistant topcoat on the surface of the substrate from bottom to top in sequence to form an anticorrosive primer layer, a fire retardant coating layer and a radiation resistant topcoat layer, thereby obtaining an anticorrosive and fire retardant sandwich structure coating.

8. Use of the anti-corrosion and fireproof sandwich structure coating for a nuclear island according to any one of claims 1 to 6 or the anti-corrosion and fireproof sandwich structure coating obtained by the preparation method according to claim 7 in the nuclear power radiation zone of a nuclear island.

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