Shielding paint for floating nuclear power platform, and preparation method and application thereof

Abstract

The application relates to a shielding paint for a floating nuclear power platform and a preparation method and application thereof. The raw materials for preparing the shielding paint in mass parts include the following components: 200-250 parts of bisphenol monomers, 80-120 parts of epoxy monomers, 40-50 parts of inorganic alkali, 80-120 parts of neutron shielding agents, 250-500 parts of gamma ray shielding agents and 350-450 parts of water, and the mass ratio of the bisphenol monomers to the epoxy monomers is (2.0-2.5):1. The preparation method comprises the following steps: mixing the components of the raw materials to obtain a mixture, and heating the mixture to make the bisphenol monomers and the epoxy monomers carry out a polymerization reaction.

Description

Technical Field

[0001] This application relates to the field of nuclear power technology, and in particular to a shielding coating for floating nuclear power platforms, its preparation method, and its application. Background Technology

[0002] Floating nuclear power platforms are a new type of small-scale nuclear power facility that mounts a nuclear reactor on a ship. They offer advantages such as high mobility, portability, and flexible heating and power supply, providing a good solution for the development of marine resources and island energy. However, the nuclear reactor and related piping systems of a floating nuclear power platform are housed within a hull constructed from a base plate. Since the base plate cannot be too heavy, the radiation-shielding concrete slabs used in land-based nuclear power plants cannot be used to construct the floating nuclear power platform. Furthermore, the compact structure of a floating nuclear power platform, coupled with the close proximity of the nuclear reactor to personnel compartments, necessitates shielding not only against neutron radiation but also against secondary gamma rays generated during the neutron shielding process, thus providing comprehensive radiation protection for personnel.

[0003] Floating nuclear power platforms use substrates made of materials such as polyethylene, boron-containing polyethylene, boron steel, and lead-boron polyethylene. These substrates are laid around the reactor compartment or other areas requiring shielding using a staggered splicing method, achieving a certain level of radiation shielding. However, gaps can appear in the substrates during installation, and these gaps gradually widen as the platform floats. The radiation dose leaking from these gaps can be substantial, posing serious radiation hazards to personnel, equipment, and the environment.

[0004] Therefore, how to provide a shielding coating to reduce leakage radiation in the substrate gap area of ​​floating nuclear power platforms and enhance the overall radiation protection effect of the compartment has become an urgent technical problem to be solved. Summary of the Invention

[0005] Therefore, it is necessary to provide a shielding coating, its preparation method, and its application that can reduce leakage radiation in the gap area of ​​the substrate of a floating nuclear power platform and enhance the overall radiation protection effect of the compartment.

[0006] A first aspect of this application provides a method for preparing a shielding coating for a floating nuclear power platform, wherein the raw materials for preparing the shielding coating, by weight, comprise the following components:

[0007]

[0008] The mass ratio of the bisphenol monomer to the epoxy monomer is (2.0-2.5):1;

[0009] The preparation method includes the following steps:

[0010] The components of the raw materials are mixed to obtain a mixture, and the mixture is heated to cause the bisphenol monomer and the epoxy monomer to undergo a polymerization reaction.

[0011] The above-mentioned method for preparing the shielding coating uses specific mass proportions of bisphenol monomer, epoxy monomer, inorganic alkali, neutron shielding agent, gamma-ray shielding agent, and water as raw materials. The bisphenol monomer and epoxy monomer undergo a polymerization reaction under the action of the inorganic alkali to form epoxy resin. By controlling the mass ratio of bisphenol monomer to epoxy monomer, the flowability of the epoxy resin can be improved, allowing it to be dispersed more uniformly in water. Simultaneously, the neutron shielding agent and gamma-ray shielding agent can also be dispersed in water, thus obtaining a shielding coating with good dispersibility and flowability. Furthermore, the neutron shielding agent can reduce neutron radiation, and the gamma-ray shielding agent can reduce secondary gamma rays generated by shielding neutron radiation. By controlling the mass proportions of the neutron shielding agent and gamma-ray shielding agent, the two shielding agents work synergistically to more effectively shield neutron and gamma rays. Therefore, the aforementioned shielding coating can be used to fill the gaps in the shielding substrate of a floating nuclear power platform. When in use, it can flow relatively evenly into the gaps, improving the dispersion of epoxy resin, neutron shielding agent and gamma-ray shielding agent, effectively reducing leakage radiation in the gaps, thereby enhancing the overall radiation protection effect of the floating nuclear power platform compartment.

[0012] Furthermore, after the aforementioned shielding coating has cured, it still retains a certain degree of flexibility during use, thus it can still provide effective radiation shielding when the floating nuclear power platform floats.

[0013] Furthermore, the above preparation method is simple, easy to implement, and can be applied on a large scale.

[0014] In some embodiments, the raw materials for preparing the shielding coating, by weight, include the following components:

[0015]

[0016] In some embodiments, the raw materials used in the preparation satisfy at least one of the following (1) to (5):

[0017] (1) The bisphenol monomer includes at least one of bisphenol A, bisphenol F and bisphenol S;

[0018] (2) The epoxy monomer includes at least one of epichlorohydrin, methyl epichlorohydrin and epichlorohydrin;

[0019] (3) The inorganic base includes sodium hydroxide;

[0020] (4) The neutron shielding agent includes at least one of boric acid and gadolinium methacrylate;

[0021] (5) The gamma-ray shielding agent includes at least one of lead tungstate, lead methacrylate and lead acetate.

[0022] In some embodiments, the mass ratio of the bisphenol monomer to the epoxy monomer is (2.2-2.4):1.

[0023] In some embodiments, the mass ratio of the neutron shielding agent to the gamma-ray shielding agent is (0.2–0.4):1.

[0024] In some embodiments, the neutron shielding agent comprises gadolinium methacrylate, and the gamma-ray shielding agent comprises lead acetate, wherein the mass ratio of gadolinium methacrylate to lead acetate is (0.2–0.3):1.

[0025] In some embodiments, the step of mixing the components of the raw materials to obtain a mixture includes:

[0026] The bisphenol monomer, the neutron shielding agent, the gamma-ray shielding agent, the inorganic base, and the water are first mixed to prepare a premix.

[0027] The epoxy monomer is added to the premix for a second mixing to obtain the mixture.

[0028] In some embodiments, the preparation method satisfies at least one of the following (6) to (8):

[0029] (6) The temperature of the first mixture is 70℃~75℃;

[0030] (7) The temperature of the second mixture is 80℃~90℃;

[0031] (8) The epoxy monomer is added after the temperature of the premix is ​​reduced to 45℃~50℃.

[0032] A second aspect of this application provides a shielding coating prepared according to the preparation method of the first aspect.

[0033] A third aspect of this application provides a method for using a shielding coating, comprising the following steps:

[0034] The shielding coating described in the second aspect is mixed with a curing agent to prepare a coating;

[0035] The coating is applied to the area of ​​the substrate to be filled.

[0036] In some embodiments, the method of use satisfies at least one of the following (9) to (11):

[0037] (9) The volume ratio of the shielding coating to the curing agent is (2.0~4.0):1;

[0038] (10) The curing agent includes at least one of polyetheramine and aromatic amine;

[0039] (11) The substrate includes at least one of tungsten boron polyethylene board, lead boron polyethylene board and boron steel board.

[0040] A fourth aspect of this application provides a shielding article, comprising a substrate and a shielding coating disposed on the substrate, wherein the raw materials for preparing the shielding coating include the shielding coating described in the second aspect. Detailed Implementation

[0041] To facilitate understanding of this application, a more complete description will be provided below. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0043] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0044] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the weights mentioned in the embodiments of this application can be well-known units of mass in the chemical industry, such as μg, mg, g, and kg.

[0045] A method for preparing a shielding coating for floating nuclear power platforms, wherein the raw materials for preparing the shielding coating, by mass parts, include the following components:

[0046]

[0047]

[0048] The mass ratio of bisphenol monomer to epoxy monomer is (2.0–2.5):1;

[0049] The above preparation method includes the following step S10:

[0050] S10. Mix the components of the raw materials to obtain a mixture, and heat the mixture to cause the bisphenol monomer and epoxy monomer to undergo a polymerization reaction.

[0051] It should be noted that the shielding coating of this embodiment can be used directly, or it can be diluted with an appropriate amount of solvent before use, or it can be used after removing an appropriate amount of water and concentrating it. This embodiment does not limit this.

[0052] Optionally, the mass fractions of bisphenol monomer can be 200, 205, 210, 215, 220, 225, 230, 235, 240, 245 or 250 parts, and other suitable selections can be made within the range of 200 to 250 parts.

[0053] Optionally, the mass fraction of the epoxy monomer can be 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 105 parts, 110 parts, 115 parts or 120 parts, and other suitable selections can be made within the range of 80 parts to 120 parts.

[0054] Optionally, the mass fraction of the inorganic base can be 40, 42, 44, 46, 48 or 50 parts, and other suitable selections can be made within the range of 40 to 50 parts.

[0055] Optionally, the mass fraction of the neutron shielding agent can be 80, 85, 90, 95, 100, 105, 110, 115 or 120 parts, and other suitable selections can be made within the range of 80 to 120 parts.

[0056] Optionally, the mass fraction of the gamma-ray shielding agent can be 250 parts, 300 parts, 350 parts, 400 parts, 450 parts or 500 parts, and other suitable selections can be made within the range of 250 parts to 500 parts.

[0057] Optionally, the mass fraction of water can be 350, 400, or 450 parts, and other suitable choices can be made within the range of 350 to 450 parts.

[0058] Optionally, the mass ratio of bisphenol monomer to epoxy monomer can be 2.0:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, or 2.5:1, and other suitable selections can be made within the range of (2.0 to 2.5):1. Understandably, bisphenol monomer and epoxy monomer can undergo a polymerization reaction under the action of an inorganic alkali to form an epoxy resin, and the resulting epoxy resin can be dispersed in water within the system, thereby giving the shielding coating good flowability. Further, when the mass ratio of bisphenol monomer to epoxy monomer is (2.0 to 2.5):1, an epoxy resin with good flowability and easy curing can be formed. When the mass ratio is less than 2.0, the formed epoxy resin contains more epoxy groups, resulting in a higher degree of crosslinking and higher viscosity, affecting the flowability of the epoxy resin; when the mass ratio is greater than 2.5, the formed epoxy resin contains fewer epoxy groups, leading to a slower curing rate and affecting the efficiency during subsequent use.

[0059] Furthermore, this application first mixes the components, then heats them to react the bisphenol monomer and epoxy monomer in the raw materials, allowing the neutron shielding agent and gamma-ray shielding agent to be more uniformly dispersed in the shielding coating. This ensures thorough mixing of the components in the resulting shielding coating, and the coating exhibits good fluidity and component dispersibility, thereby enhancing the radiation shielding effect.

[0060] The shielding coating preparation method in this embodiment uses specific mass proportions of bisphenol monomer, epoxy monomer, inorganic alkali, neutron shielding agent, gamma-ray shielding agent, and water as raw materials. The bisphenol monomer and epoxy monomer undergo a polymerization reaction under the action of the inorganic alkali to form epoxy resin. By controlling the mass ratio of bisphenol monomer to epoxy monomer, the flowability of the epoxy resin can be improved, allowing it to be more uniformly dispersed in water. Simultaneously, the neutron shielding agent and gamma-ray shielding agent can also be dispersed in water, thus obtaining a shielding coating with good dispersibility and flowability. Furthermore, the neutron shielding agent can reduce neutron radiation, and the gamma-ray shielding agent can reduce secondary gamma rays generated by shielding neutron radiation. By controlling the mass proportions of the neutron shielding agent and gamma-ray shielding agent, the two shielding agents work synergistically to more effectively shield neutron and gamma rays. Therefore, the aforementioned shielding coating can be used to fill the gaps in the shielding substrate of a floating nuclear power platform. When in use, it can flow relatively evenly into the gaps, improving the dispersion of epoxy resin, neutron shielding agent and gamma-ray shielding agent, effectively reducing leakage radiation in the gaps, thereby enhancing the overall radiation protection effect of the floating nuclear power platform compartment.

[0061] Furthermore, after the aforementioned shielding coating has cured, it still retains a certain degree of flexibility during use, thus it can still provide effective radiation shielding when the floating nuclear power platform floats.

[0062] Furthermore, the above preparation method is simple, easy to implement, and can be applied on a large scale.

[0063] In some embodiments, the raw materials for preparing the shielding coating consist of the following components:

[0064]

[0065] The mass ratio of bisphenol monomer to epoxy monomer is (2.0~2.5):1.

[0066] In some embodiments, the raw materials for preparing the shielding coating, by weight, include the following components:

[0067]

[0068] When using the above-mentioned proportions of bisphenol monomer, epoxy monomer, inorganic base, neutron shielding agent, gamma-ray shielding agent, and water as raw materials, the synergistic effect between the raw material components can be more fully utilized, resulting in a shielding coating with better fluidity and more uniform component dispersion. This further enhances the radiation shielding effect of the above-mentioned shielding materials. When applied to floating nuclear power platforms, it can more effectively enhance the radiation protection effect.

[0069] In some embodiments, the raw materials for preparing the shielding coating consist of the following components:

[0070]

[0071] In some embodiments, the bisphenol monomer includes at least one of bisphenol A, bisphenol F, and bisphenol S.

[0072] In some of these embodiments, the epoxy monomer includes at least one of epichlorohydrin, methyl epichlorohydrin, and epichlorohydrin.

[0073] In some embodiments, the inorganic base includes sodium hydroxide.

[0074] In some embodiments, the neutron shielding agent includes at least one of boric acid and gadolinium methacrylate.

[0075] In some embodiments, the gamma-ray shielding agent includes at least one of lead tungstate, lead methacrylate, and lead acetate.

[0076] In some embodiments, the mass ratio of bisphenol monomer to epoxy monomer is (2.2–2.4):1. When the mass ratio of the two monomers is within the above range, the flowability of the resulting epoxy resin can be further improved.

[0077] In some embodiments, the mass ratio of neutron shielding agent to gamma-ray shielding agent is (0.2–0.4):1. Optionally, the mass ratio of neutron shielding agent to gamma-ray shielding agent can be 0.2:1, 0.25:1, 0.3:1, 0.35:1, or 0.4:1, and other suitable selections can be made within the range of (0.2–0.4):1. When the mass ratio of the two shielding agents is within the above range, the synergistic effect between the two can be better utilized, which can not only more effectively reduce neutron radiation, but also reduce gamma rays generated due to neutron radiation shielding.

[0078] In some embodiments, the neutron shielding agent includes gadolinium methacrylate, and the gamma-ray shielding agent includes lead acetate, wherein the mass ratio of gadolinium methacrylate to lead acetate is (0.2-0.3):1.

[0079] Understandably, gadolinium methacrylate exhibits better compatibility with epoxy resins compared to metal powder, gadolinium salts, or inorganic acid-based neutron shielding agents. Similarly, lead methacrylate and lead acetate show better compatibility with epoxy resins compared to lead powder or lead salts. Therefore, using gadolinium methacrylate and lead acetate as shielding agents can improve the dispersibility of neutron and gamma-ray shielding agents in shielding coatings, thereby enhancing the shielding effect against neutrons and gamma rays. Furthermore, when the mass ratio of gadolinium methacrylate to lead acetate is (0.2–0.3):1, the synergistic effect of gadolinium methacrylate and lead acetate can be more fully utilized, optimizing the shielding effect.

[0080] In some embodiments, step S10, which involves mixing the components of the raw materials to obtain a mixture, includes:

[0081] S101. Bisphenol monomer, neutron shielding agent, γ-ray shielding agent, inorganic base and water are mixed in the first step to prepare a premix.

[0082] S102. Add epoxy monomers to the premix and perform a second mixing to obtain a mixture.

[0083] Understandably, the above preparation method involves mixing the raw materials in two steps, which allows the neutron shielding agent and gamma-ray shielding agent to be uniformly dispersed in the coating, reducing the impact of the generated epoxy resin on the dispersibility of the two shielding agents.

[0084] In some embodiments, the temperature of the first mixing is 70°C to 75°C. Optionally, the temperature of the first mixing can be 70°C, 71°C, 72°C, 73°C, 74°C, or 75°C.

[0085] In some embodiments, the temperature of the second mixing is 80°C to 90°C. Optionally, the temperature of the second mixing can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, or 90°C.

[0086] In some embodiments, the epoxy monomer is added after the temperature of the premix is ​​lowered to 45°C to 50°C. Optionally, the epoxy monomer is added after the temperature is lowered to 45°C, 46°C, 47°C, 48°C, 49°C, or 50°C.

[0087] Furthermore, this application also provides a shielding coating for floating nuclear power platforms prepared according to the above preparation method.

[0088] Furthermore, this application provides a method for using the aforementioned shielding coating for floating nuclear power platforms, including the following steps S20 to S30.

[0089] S20. Mix the shielding coating with the curing agent to prepare the coating;

[0090] S30. Apply the coating to the area to be filled on the substrate.

[0091] Understandably, the shielding coating can flow to the area to be filled on the substrate, and the epoxy resin in the shielding coating can effectively fill the area to be filled after curing, thereby reducing the radiation of the area to be filled.

[0092] In some embodiments, the volume ratio of the shielding coating to the curing agent is (2.0–4.0):1. Optionally, the volume ratio of the shielding coating to the curing agent can be 2.0:1, 2.5:1, 3:1, 3.5:1, or 4.0:1, and other suitable selections can be made within the range of (2.0–4.0):1. By adjusting the above volume ratio, the epoxy resin in the shielding coating can have a suitable degree of curing, thereby ensuring the strength and flexibility of the cured shielding material.

[0093] In some embodiments, the curing agent includes at least one of polyetheramines and aromatic amines. Exemplarily, aromatic amines include, but are not limited to, m-phenylenediamine and m-phenylenediamine.

[0094] In some embodiments, the substrate includes at least one selected from tungsten boron polyethylene board, lead boron polyethylene board, and boron steel board. Exemplarily, the above-described substrate can be used in compartments within a floating nuclear power plant where radiation is present. Specifically, the substrate can be disposed at locations such as the bottom of the compartment and the walls of the compartment, or at other locations within the compartment. Further, multiple substrates can be arranged in the compartment by splicing them together.

[0095] In some embodiments, the thickness of the substrate is 20 mm to 200 mm.

[0096] In some embodiments, the area to be filled includes a gap between adjacent substrates.

[0097] In some embodiments, the following steps are included after step S20 and before step S30:

[0098] The area to be filled on the substrate is dried.

[0099] In some embodiments, an iodine-tungsten lamp is used for drying. Optionally, the iodine-tungsten lamp has a power of 150W to 1500W and a baking temperature of 60°C to 80°C.

[0100] In some embodiments, step S30 is followed by the following steps:

[0101] In an environment of 25℃~30℃ and relative humidity <80%, allow the coating to cure and dry for 3~14 days.

[0102] In addition, this application also provides a shielding article for a floating nuclear power platform, including a substrate and a shielding coating disposed on the substrate, wherein the raw materials for preparing the shielding coating include the shielding paint mentioned above.

[0103] The following are specific examples.

[0104] Example 1

[0105] (1) Preparation of shielding coating

[0106] The raw materials for preparing the shielding coating, by mass parts, include the following components:

[0107]

[0108] The specific preparation method is as follows:

[0109] Sodium hydroxide was mixed with water, followed by the addition of bisphenol A, gadolinium methacrylate, and lead acetate. The mixture was heated to 70°C and stirred for 30 minutes to obtain a premix. The premix was then cooled to 47°C, and epichlorohydrin was added to obtain a mixture. The mixture was then heated to 85°C and stirred for 1 hour to obtain a shielding coating.

[0110] Gadolinium methacrylate was prepared by the following method: Equimolar amounts of gadolinium oxide (Gd₂O₃) and methyl methacrylate (MAA) were added to water and stirred in a water bath at 70°C for 2 hours. A first filtration was then performed, and the filtrate was subjected to vacuum distillation. A second filtration was then performed, and the filtrate was collected. An appropriate amount of ethanol was added to the filtrate from the second filtration for precipitation. After solid precipitate was observed, a third filtration was performed, and the filter residue was collected. The residue was then washed and dried to obtain gadolinium methacrylate (i.e., Gd(MAA)₃).

[0111] (2) Use of shielding coating

[0112] The shielding coating from step (1) was mixed with the polyetheramine curing agent at a volume ratio of 3:1, and then applied to the surface of the substrate. After coating, the ambient temperature was maintained at 25℃~30℃ and the relative humidity was <80% for 14 days, and the uncured shielding coating was removed to form a shielding coating with a thickness of about 2mm on the substrate.

[0113] The substrate is a tungsten boron polyethylene board. Before applying the shielding coating, the substrate is baked with an iodine tungsten lamp to keep the surface of the substrate dry. The iodine tungsten lamp has a power of 1000W and a baking temperature of 70℃.

[0114] Example 2

[0115] The preparation method of Example 2 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0116]

[0117]

[0118] Example 3

[0119] The preparation method of Example 3 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0120]

[0121] Example 4

[0122] The preparation method of Example 4 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0123]

[0124] Example 5

[0125] The preparation method of Example 5 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0126]

[0127] Example 6

[0128] The preparation method of Example 6 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0129]

[0130] Example 7

[0131] The preparation method of Example 7 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0132]

[0133]

[0134] Example 8

[0135] The preparation method of Example 8 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0136]

[0137] Example 9

[0138] The preparation method of Example 9 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0139]

[0140] Example 10

[0141] The preparation method of Example 10 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0142]

[0143]

[0144] Comparative Example 1

[0145] The preparation method of Comparative Example 1 is basically the same as that of Example 1, except that the raw materials for preparing the neutron and gamma-ray shielding material include the following components:

[0146]

[0147] Comparative Example 2

[0148] The preparation method of Comparative Example 2 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0149]

[0150] Comparative Example 3

[0151] The preparation method of Comparative Example 3 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0152]

[0153] Comparative Example 4

[0154] The preparation method of Comparative Example 4 is basically the same as that of Example 1, except that the raw materials for preparing the shielding coating include the following components:

[0155]

[0156] Comparative Example 5

[0157] The raw materials for Comparative Example 5 included epoxy resin, gadolinium methacrylate, methacrylic acid, and water. The specific preparation method is as follows:

[0158] (1) Preparation of epoxy resin

[0159] 50 parts by weight of sodium hydroxide and 450 parts by weight of water were mixed, followed by the addition of 230 parts by weight of bisphenol A. The mixture was heated to 70°C and stirred for 30 minutes, then cooled to 47°C. Next, 100 parts by weight of epichlorohydrin were added, and the mixture was heated to 85°C and stirred for 1 hour to obtain epoxy resin.

[0160] (2) Preparation of shielding coating

[0161] 100 parts by weight of gadolinium methacrylate and 400 parts by weight of lead acetate were added to the above epoxy resin, and the mixture was stirred at 70°C for 30 minutes to prepare a shielding coating.

[0162] (3) Use of shielding coating

[0163] The shielding coating from step (2) was mixed with the polyetheramine curing agent at a volume ratio of 3:1, and then applied to the surface of the substrate. After coating, the ambient temperature was maintained at 25℃~30℃ and the relative humidity was <80% for 14 days, and the uncured shielding coating was removed, thereby forming a shielding coating with a thickness of about 2mm on the substrate.

[0164] The substrate is a tungsten boron polyethylene board. Before applying the shielding coating, the substrate is baked with an iodine tungsten lamp to keep the surface of the substrate dry. The iodine tungsten lamp has a power of 1000W and a baking temperature of 70℃.

[0165] The raw materials for preparing the shielding coatings of Examples 1-10 and Comparative Examples 1-5 are shown in Table 1 below. In Table 1, the unit of each component is parts by mass, A / B represents the mass ratio of bisphenol A to epichlorohydrin, and C / D represents the mass ratio of neutron shielding agent to gamma-ray shielding agent.

[0166] Table 1

[0167]

[0168]

[0169] The shielding coatings (all with a thickness of 2 mm) of Examples 1-10 and Comparative Examples 1-5 were subjected to thermal neutron shielding performance tests and gamma-ray shielding performance tests. The specific test methods are as follows, and the test results are shown in Table 2 below.

[0170] 1. Test method for thermal neutron shielding performance

[0171] Tests were conducted using a neutron dose equivalent rate standard device, measuring the count rate of the thermal neutron detector with and without the sample being tested for shielding. The position and orientation of the thermal neutron detector remained constant throughout the measurement process, and the plane of the sample was parallel to the thermal neutron emission plane of the moderator. The thermal neutron shielding performance of the sample was determined by comparing the count rate results under the two conditions.

[0172] To prevent neutrons from other directions from affecting the test results, the thermal neutron detector was placed in a cubic cadmium shielded box made of cadmium sheets with a thickness of 2 mm. The side of the cadmium shield facing the moderator's thermal neutron emission plane had no shielding plate, ensuring that the thermal neutron detector only received thermal neutrons from the moderator's direction. The specific experimental steps are as follows:

[0173] (1) Place the cadmium shielding box and detector in the center of the test area and measure the detector count rate when there is no sample.

[0174] (2) Keep the positions of the cadmium shielding box and the detector unchanged, place the sample to be tested on the surface of the cadmium shielding box facing the thermal neutron emission plane of the moderator, and measure the count rate of the detector when there is a sample.

[0175] (3) The thermal neutron shielding performance of the sample is calculated using the following formula.

[0176]

[0177] Where η represents the shielding performance, and C s C represents the count rate after adding shielding material. b This represents the count rate when the cadmium box has no sample.

[0178] 2. Gamma-ray shielding performance test

[0179] The tested sample in Co-60 (i.e. 60 Measurements were performed using a collimated radiation beam (Co). The specific test methods and conditions are as follows:

[0180] (1) The sample being tested is in 60 Measurements were performed using a Co-collimated radiation beam.

[0181] (2) The measuring instruments are calibrated to national standards;

[0182] (3) The instrument is fully preheated, and the geometric center of the source is on the same axis as the sample and the detector.

[0183] Table 2

[0184] Group Thermal neutron shielding performance gamma-ray shielding performance Example 1 83％ 32％ Example 2 72％ 32％ Example 3 81％ 31％ Example 4 82％ 27％ Example 5 83％ 28％ Example 6 80％ 30％ Example 7 78％ 29％ Example 8 71％ 26％ Example 9 72％ 32％ Example 10 80％ 25％ Comparative Example 1 75％ 25％ Comparative Example 2 80％ 24％ Comparative Example 3 71％ 22％ Comparative Example 4 72％ 23％ Comparative Example 5 68％ 20％

[0185] As shown in Table 2 above, the shielding coatings of Examples 1 to 10 have good thermal neutron shielding performance and gamma-ray shielding performance after curing. Among them, the thermal neutron shielding performance of Example 1 can reach 83%, and the gamma-ray shielding performance can reach 32%.

[0186] Compared to Example 1, Comparative Example 1 had a higher content of neutron shielding agent, resulting in reduced thermal neutron shielding performance and a decrease in gamma-ray shielding performance; Comparative Example 2 had a higher content of gamma-ray shielding agent, but its gamma-ray shielding performance actually decreased. The test results of Comparative Examples 1 and 2 show that this application achieves a synergistic effect by controlling the content of neutron and gamma-ray shielding agents in the raw materials, thereby simultaneously improving the neutron and gamma-ray shielding performance of the shielding coating.

[0187] Compared to Example 1, the bisphenol A to epichlorohydrin ratio in Comparative Example 3 was lower, resulting in decreased shielding performance. This is because the epoxy resin in the shielding coating of Comparative Example 3 had more epoxy groups, leading to poor coating fluidity and hindering the dispersion of the neutron and gamma-ray shielding agents. This meant that the two shielding agents would agglomerate, affecting the shielding performance of the coating. In Comparative Example 4, the bisphenol A to epichlorohydrin ratio was higher, but its shielding performance also decreased. This is because the epoxy resin in the shielding coating of Comparative Example 4 had fewer epoxy groups, resulting in a slower curing rate. Under the same curing time, its degree of curing was lower, and the shielding agent content in the resulting coating was relatively lower, thus deteriorating its shielding performance. As can be seen from Comparative Examples 3 and 4, this application, by controlling the mass ratio of epoxy monomers to bisphenol monomers, achieves better flowability and curing properties in the formed epoxy resin, effectively improving the shielding performance of the coating.

[0188] Compared to Example 1, Comparative Example 5 first prepared an epoxy resin and then dispersed the shielding agent in the prepared epoxy resin. The shielding performance of Comparative Example 5 was significantly reduced, indicating that this application improved the shielding performance by optimizing the preparation method of the shielding coating, so that the two shielding agents were better dispersed in the coating.

[0189] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0190] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for preparing a shielding coating for a floating nuclear power platform, characterized in that, The raw materials for preparing the shielding coating, by weight, include the following components: 200-250 parts of bisphenol monomer 80-120 parts of epoxy monomer 40-50 parts of inorganic base 80-120 parts of neutron shielding agent 250-500 parts of gamma-ray shielding agent, and 350-450 parts water; The mass ratio of the bisphenol monomer to the epoxy monomer is (2.0~2.5):1; The neutron shielding agent includes gadolinium methacrylate; The gamma-ray shielding agent includes lead acetate; The mass ratio of the neutron shielding agent to the gamma-ray shielding agent is (0.2~0.3):1; The preparation method includes the following steps: The components of the raw materials are mixed to obtain a mixture, and the mixture is heated to cause the bisphenol monomer and the epoxy monomer to undergo a polymerization reaction.

2. The method for preparing the shielding coating as described in claim 1, characterized in that, The raw materials for preparing the shielding coating, by weight, include the following components: 220-240 parts of bisphenol monomer 90-115 parts epoxy monomer 40-50 parts of inorganic base 88-115 parts of neutron shielding agent 300-450 parts of gamma-ray shielding agent, and 350 to 450 parts water.

3. The method for preparing the shielding coating as described in claim 1, characterized in that, The raw materials used in the preparation satisfy at least one of the following (1) to (3): (1) The bisphenol monomer includes at least one of bisphenol A, bisphenol F and bisphenol S; (2) The epoxy monomer includes at least one of epichlorohydrin, methyl epichlorohydrin and epichlorohydrin; (3) The inorganic base includes sodium hydroxide.

4. The method for preparing the shielding coating according to any one of claims 1 to 3, characterized in that, The mass ratio of the bisphenol monomer to the epoxy monomer is (2.2~2.4):

1.

5. The method for preparing the shielding coating according to any one of claims 1 to 3, characterized in that, The step of mixing the components of the raw material to obtain a mixture includes: The bisphenol monomer, the neutron shielding agent, the gamma-ray shielding agent, the inorganic base, and the water are first mixed to prepare a premix. The epoxy monomer is added to the premix for a second mixing to obtain the mixture.

6. The method for preparing the shielding coating as described in claim 5, characterized in that, The preparation method satisfies at least one of the following (4) to (6): (4) The temperature of the first mixture is 70 ℃~75 ℃; (5) The temperature of the second mixture is 80 ℃~90 ℃; (6) The epoxy monomer is added after the temperature of the premix is ​​reduced to 45 ℃~50 ℃.

7. A shielding coating for floating nuclear power platforms, characterized in that, Prepared by the preparation method according to any one of claims 1 to 6.

8. A method for applying a shielding coating for a floating nuclear power platform, characterized in that, Includes the following steps: The shielding coating described in claim 7 is mixed with a curing agent to prepare a coating. The coating is applied to the area of ​​the substrate to be filled.

9. The method of using the shielding coating as described in claim 8, characterized in that, The method of use satisfies at least one of the following (7) to (9): (7) The volume ratio of the shielding coating to the curing agent is (2.0~4.0):1; (8) The curing agent includes at least one of polyetheramine and aromatic amine; (9) The substrate includes at least one of tungsten boron polyethylene board, lead boron polyethylene board and boron steel board.

10. A shielding product for a floating nuclear power platform, characterized in that, It includes a substrate and a shielding coating disposed on the substrate, wherein the raw materials for preparing the shielding coating include the shielding coating of claim 7.

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