Electromagnetic shielding concrete and method for producing the same
By using a combination of ferrocene-based MOF-coated graphite and fluorosilicone-modified straw fiber in concrete, the problem of uneven electromagnetic shielding function in electromagnetic shielding concrete is solved, achieving concrete with high electromagnetic shielding and high water permeability, suitable for places such as computer rooms and military facilities.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHAOXING SHANGJIAN SHUNXING CONCRETE CO LTD
- Filing Date
- 2023-06-26
- Publication Date
- 2026-05-29
AI Technical Summary
The electromagnetic shielding functional components in existing electromagnetic shielding concrete are difficult to disperse evenly, resulting in uneven electromagnetic shielding performance and difficulty in achieving both high permeability and mechanical properties.
Electromagnetic shielding concrete with a three-dimensional network structure was prepared by using ferrocene-based MOF-coated graphite organic-inorganic hybrid material as a functional additive and modifying straw fibers with fluorosilicone. This method avoids the use of rigid stainless steel fibers and achieves high electromagnetic shielding performance and high water permeability of the concrete.
It achieves a balance between high electromagnetic shielding performance and water permeability of concrete, meeting the long-term use requirements of special locations.
Smart Images
Figure BDA0004303269230000071 
Figure BDA0004303269230000081
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of concrete, and more particularly to an electromagnetic shielding concrete and its preparation method. Background Technology
[0002] With the development of electronic technology, the protection against electromagnetic interference and the suppression of electromagnetic radiation have become urgent problems to be solved. However, existing electromagnetic shielding materials, such as conductive rubber and electromagnetic shielding coatings, are costly and have limited application ranges. Concrete is the most widely used and cost-effective building material. New types of concrete with electromagnetic shielding properties can increase the application value of concrete, prevent the leakage of electronic information inside buildings, reduce environmental pollution from external electromagnetic radiation sources, and ensure the security of electronic information and the health of personnel. Current technologies mainly use materials such as coke, graphite, carbon fiber, and stainless steel fiber to give concrete electromagnetic shielding properties, as disclosed in CN109336515A and CN112110700B. However, stainless steel fiber is difficult to process due to its rigidity, and when added to concrete, it is difficult to mix evenly with other concrete components, resulting in poor workability. On the other hand, due to the poor compatibility between graphite and other components in concrete, the distribution of graphite in electromagnetic shielding concrete is uneven, making the concrete prone to localized deficiencies in electromagnetic shielding function after construction. This has led to problems such as the difficulty in achieving electromagnetic shielding performance, high permeability, and mechanical properties in existing electromagnetic shielding concrete. Summary of the Invention
[0003] In view of the shortcomings of the prior art, the present invention provides an electromagnetic shielding concrete to solve the problem that the electromagnetic shielding functional components in the raw materials of existing electromagnetic shielding concrete are difficult to disperse evenly, resulting in the electromagnetic shielding concrete being unable to take into account the overall electromagnetic shielding performance, high permeability and mechanical properties.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0005] An electromagnetic shielding concrete, the concrete being composed of the following raw materials in significant proportions: 55-65 parts cement, 100 parts crushed stone, 50-55 parts sand, 12-15 parts fly ash, 16-20 parts water, 0.5-2.5 parts fluorosilicone modified straw fiber, and 1.5-5.5 parts functional additives.
[0006] Preferably, the functional additive is an organic-inorganic hybrid material of ferrocene-based MOF-coated graphite.
[0007] Preferably, the ferrocene-based MOF is obtained by using ferrocene dicarboxylic acid as an organic ligand and reacting with metal ions in a hydrothermal reactor to form a network structure.
[0008] Preferably, the ferrocene dicarboxylic acid is 1,1'-ferrocene diboronic acid and / or 1,1'-ferrocene dicarboxylic acid. The ferrocene dicarboxylic acid of the present invention has a ferrocene main structure with good electrical conductivity, which can improve the electromagnetic shielding performance of concrete; simultaneously, the two carboxyl active sites on the ferrocene dicarboxylic acid can combine with metal ions to form a network structure through molecular self-assembly.
[0009] Preferably, the metal ion is at least one selected from iron ions, nickel ions, and copper ions. The present invention uses iron ions, nickel ions, and copper ions as metal ions to bind with organic ligands, which can further enhance the electromagnetic shielding performance of concrete.
[0010] Preferably, the reaction conditions for the molecular self-assembly reaction are: reflux reaction at 90–120°C for 12–24 hours.
[0011] The functional additive of this invention combines graphite with a conductive ferrocene-based MOF coated on its outer surface. The two work synergistically to give concrete excellent electromagnetic shielding performance. At the same time, the three-dimensional network structure of the ferrocene-based MOF allows concrete to achieve high electromagnetic shielding performance without the need for rigid stainless steel fibers.
[0012] Preferably, the modification method of the fluorosilicone modified straw fiber is as follows: first, the straw fiber is soaked in a mixed solution of hydrogen peroxide and sulfuric acid for a period of time to activate it, thereby obtaining hydroxyl straw fiber; then, an intermediate product obtained by the addition reaction of vinyl fluorosilane and acrolein is added, and in a high-pressure reactor, the hydroxyl straw fiber and the intermediate product undergo a hydroxyl aldehyde reaction to obtain fluorosilicone modified straw fiber.
[0013] Preferably, the vinyl fluorosilane is at least one of vinyl dimethyl fluorosilane, dimethyl (trifluoromethyl) vinyl silane, and vinyl (3,3,3-trifluoropropyl) dimethyl silane.
[0014] Preferably, the molar ratio of vinyl fluorosilane to acrolein is 1:1 to 1.3; and the mass ratio of hydroxyl straw fiber to intermediate product is 10:1 to 3.
[0015] Another aspect of the present invention is to provide a method for preparing electromagnetic shielding concrete as described above. The method comprises: weighing the following concrete raw materials by weight: 55-65 parts cement, 100 parts crushed stone, 50-55 parts sand, 12-15 parts fly ash, 16-20 parts water, 0.5-2.5 parts fluorosilicone modified straw fiber and 1.5-5.5 parts functional additives, and mixing them evenly at a speed of 200-500 rpm to obtain the electromagnetic shielding concrete.
[0016] The beneficial effects of this invention are:
[0017] The electromagnetic shielding concrete of this invention possesses excellent mechanical properties. By using a ferrocene-based MOF-coated graphite organic-inorganic hybrid material as a functional additive, not only is the graphite uniformly dispersed in the concrete, but the ferrocene-based MOF with its three-dimensional network structure on the graphite surface also allows the concrete to achieve high electromagnetic shielding performance without the need for rigid stainless steel fibers. Furthermore, the addition of fluorosilicone-modified straw fibers to this electromagnetic shielding concrete not only improves its compressive strength but also its permeability. This concrete can meet the long-term use requirements of special locations such as computer rooms and military facilities that require electromagnetic shielding. Detailed Implementation
[0018] The following description is intended to disclose the invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.
[0019] Example 1
[0020] The electromagnetic shielding concrete of this embodiment is composed of the following key proportions of raw materials: 55 parts cement, 100 parts...
[0021] Crushed stone, 50 parts sand, 12 parts fly ash, 16 parts water, 0.5 parts fluorosilicone modified straw fiber, and 1.5 parts functional additives.
[0022] The functional additive is an organic-inorganic hybrid material of graphite coated with ferrocene-based MOF. Its preparation method is as follows: 200g of graphite oxide powder is uniformly dispersed in 1L of a 50% (w / w) ethanol aqueous solution by ultrasonication to obtain a graphite oxide mixture, which is then added to a hydrothermal reactor. 1,1'-ferrocene diboronic acid, as the MOF organic ligand, is dissolved in DMF solvent to prepare a 20% (w / w) solution A. Ferric nitrate is dissolved in deionized water to prepare a 0.2 mol / L ferric ion molar concentration B. Solutions A and B are added to the hydrothermal reactor at a certain feed rate, with a 1:3 molar ratio of 1,1'-ferrocene diboronic acid to ferric nitrate. The reactor is refluxed at 105°C for 18 hours, allowing for molecular self-assembly on the graphite powder surface. After aging for 12 hours, a ferrocene-based MOF-coated graphite product with a network structure is obtained, which is the functional additive of this embodiment.
[0023] The modification method for the fluorosilicone-modified straw fiber is as follows: First, 150g of straw fiber is activated by soaking it in 500mL of a mixed solution of hydrogen peroxide and sulfuric acid (volume ratio 3:2) for 1 hour to obtain hydroxyl-modified straw fiber. Then, an intermediate product obtained by the addition reaction of vinyldimethylfluorosilane and acrolein is added, and the two are reacted at 60℃ under the action of ammonium persulfate as an initiator. An 80% volume concentration ethanol solution is added to a high-pressure reactor, followed by the addition of hydroxyl-modified straw fiber and the intermediate product at a mass ratio of 10:1. The hydroxyl-modified straw fiber and the intermediate product undergo an aldol reaction to obtain fluorosilicone-modified straw fiber. The reaction pressure of the high-pressure reactor is set to 0.15MPa, and the reaction temperature is set to 80℃. The molar ratio of vinyldimethylfluorosilane to acrolein is 1:1.1.
[0024] The method for preparing electromagnetic shielding concrete in this embodiment is simple to operate. The following concrete raw materials are weighed according to their weight: 55 parts cement, 100 parts crushed stone, 50 parts sand, 12 parts fly ash, 16 parts water, 0.5 parts fluorosilicone modified straw fiber and 1.5 parts functional additives. The mixture is stirred and mixed evenly at a speed of 300 rpm to obtain the electromagnetic shielding concrete.
[0025] Example 2
[0026] The electromagnetic shielding concrete of this embodiment is composed of the following key proportions of raw materials: 60 parts cement, 100 parts...
[0027] Crushed stone, 52 parts sand, 14 parts fly ash, 18 parts water, 1.5 parts fluorosilicone modified straw fiber, and 3.5 parts functional additives.
[0028] The functional additive is an organic-inorganic hybrid material of graphite coated with ferrocene-based MOF. Its preparation method is as follows: 250g of graphite oxide powder is uniformly dispersed in 1L of a 50% (w / w) ethanol aqueous solution by ultrasonication to obtain a graphite oxide mixture, which is then added to a hydrothermal reactor. 1,1'-ferrocene diboronic acid, as the MOF organic ligand, is dissolved in DMF solvent to prepare a 20% (w / w) solution A. Nickel nitrate is dissolved in deionized water to prepare a nickel ion molar concentration B of 0.4 mol / L. Solutions A and B are added to the hydrothermal reactor at a certain feed rate, with a 1:2 molar ratio of 1,1'-ferrocene diboronic acid to nickel nitrate. The reactor is refluxed at 90°C for 12 hours, allowing for molecular self-assembly on the graphite powder surface. After aging for 8 hours, a ferrocene-based MOF-coated graphite product with a network structure is obtained, which is the functional additive of this embodiment.
[0029] The modification method for the fluorosilicone-modified straw fiber is as follows: First, 180g of straw fiber is activated by soaking it in 500mL of a mixed solution of hydrogen peroxide and sulfuric acid (volume ratio 2:1) for 2 hours to obtain hydroxyl-modified straw fiber. Then, an intermediate product obtained by the addition reaction of dimethyl(trifluoromethyl)vinylsilane and acrolein is added, and the two are reacted at 60℃ under the action of ammonium persulfate as an initiator. An 80% volume concentration ethanol solution is added to a high-pressure reactor, followed by hydroxyl-modified straw fiber and the intermediate product (mass ratio 10:2). The hydroxyl-modified straw fiber and the intermediate product undergo an aldol reaction to obtain fluorosilicone-modified straw fiber. The reaction pressure of the high-pressure reactor is set to 0.2MPa, and the reaction temperature is set to 70℃. The molar ratio of dimethyl(trifluoromethyl)vinylsilane to acrolein is 1:1.2.
[0030] The method for preparing electromagnetic shielding concrete in this embodiment is simple to operate. The following concrete raw materials are weighed according to their weight: 60 parts cement, 100 parts crushed stone, 52 parts sand, 14 parts fly ash, 18 parts water, 1.5 parts fluorosilicone modified straw fiber and 3.5 parts functional additives. The mixture is stirred and mixed evenly at a speed of 300 rpm to obtain the electromagnetic shielding concrete.
[0031] Example 3
[0032] The electromagnetic shielding concrete of this embodiment is composed of the following key proportions of raw materials: 65 parts cement, 100 parts...
[0033] Crushed stone, 55 parts sand, 15 parts fly ash, 20 parts water, 2.5 parts fluorosilicone modified straw fiber, and 5.5 parts functional additives.
[0034] The functional additive is an organic-inorganic hybrid material of graphite coated with ferrocene-based MOF. Its preparation method is as follows: 300g of graphite oxide powder is uniformly dispersed in 1L of a 50% (w / w) ethanol aqueous solution by ultrasonication to obtain a graphite oxide mixture, which is then added to a hydrothermal reactor. 1,1'-ferrocene diboronic acid, as the MOF organic ligand, is dissolved in DMF solvent to prepare a 20% (w / w) solution A. Copper nitrate is dissolved in deionized water to prepare a copper ion molar concentration B of 0.6 mol / L. Solutions A and B are added to the hydrothermal reactor at a certain feed rate, with a 1:3 molar ratio of 1,1'-ferrocene diboronic acid to copper nitrate. The reactor is refluxed at 120°C for 12 hours, allowing for molecular self-assembly on the graphite powder surface. After aging for 6 hours, a ferrocene-based MOF-coated graphite product with a network structure is obtained, which is the functional additive of this embodiment.
[0035] The modification method for the fluorosilicone-modified straw fiber is as follows: First, 210g of straw fiber is activated by soaking it in 500mL of a 1:1 mixture of hydrogen peroxide and sulfuric acid for 3 hours to obtain hydroxyl-modified straw fiber. Then, an intermediate product obtained by the addition reaction of vinyl(3,3,3-trifluoropropyl)dimethylsilane and acrolein is added, and the two are reacted at 60℃ under the action of ammonium persulfate as an initiator. An 80% volume concentration ethanol solution is added to a high-pressure reactor, followed by hydroxyl-modified straw fiber and the intermediate product at a mass ratio of 10:3. The hydroxyl-modified straw fiber and the intermediate product undergo an aldol reaction to obtain fluorosilicone-modified straw fiber. The reaction pressure of the high-pressure reactor is set to 0.25MPa, and the reaction temperature is set to 85℃. The molar ratio of vinyl(3,3,3-trifluoropropyl)dimethylsilane to acrolein is 1:1.3.
[0036] The method for preparing electromagnetic shielding concrete in this embodiment is simple to operate. The following concrete raw materials are weighed according to their weight: 65 parts cement, 100 parts crushed stone, 55 parts sand, 15 parts fly ash, 20 parts water, 2.5 parts fluorosilicone modified straw fiber and 5.5 parts functional additives. The mixture is stirred and mixed evenly at a speed of 500 rpm to obtain the electromagnetic shielding concrete.
[0037] Example 4
[0038] The electromagnetic shielding concrete of this embodiment is composed of the following key proportions of raw materials: 57 parts cement, 100 parts...
[0039] Crushed stone, 52 parts sand, 13 parts fly ash, 17 parts water, 1 part fluorosilicone modified straw fiber, and 2.5 parts functional additives.
[0040] The functional additive is an organic-inorganic hybrid material of graphite coated with ferrocene-based MOF. Its preparation method is as follows: 200g of graphite oxide powder is uniformly dispersed in 1L of a 50% (w / w) ethanol aqueous solution by ultrasonication to obtain a graphite oxide mixture, which is then added to a hydrothermal reactor. 1,1'-ferrocene dicarboxylic acid, as the MOF organic ligand, is dissolved in DMF solvent to prepare a 20% (w / w) solution A. Ferric nitrate is dissolved in deionized water to prepare a 0.2 mol / L ferric ion molar concentration (W / w) solution B. Solutions A and B are added to the hydrothermal reactor at a certain feed rate, with a 1:3 molar ratio of 1,1'-ferrocene dicarboxylic acid to ferric nitrate. The reactor is refluxed at 90°C for 24 hours, allowing for molecular self-assembly on the graphite powder surface. After aging for 12 hours, a ferrocene-based MOF-coated graphite product with a network structure is obtained, which is the functional additive of this embodiment.
[0041] The modification method for the fluorosilicone-modified straw fiber is as follows: First, 150g of straw fiber is activated by soaking it in 500mL of a mixed solution of hydrogen peroxide and sulfuric acid (volume ratio 3:2) for 1 hour to obtain hydroxyl-modified straw fiber. Then, an intermediate product obtained by the addition reaction of vinyldimethylfluorosilane and acrolein is added, and the two are reacted at 60℃ under the action of ammonium persulfate as an initiator. An 80% volume concentration ethanol solution is added to a high-pressure reactor, followed by the addition of hydroxyl-modified straw fiber and the intermediate product at a mass ratio of 10:1. The hydroxyl-modified straw fiber and the intermediate product undergo an aldol reaction to obtain fluorosilicone-modified straw fiber. The reaction pressure of the high-pressure reactor is set to 0.15MPa, and the reaction temperature is set to 80℃. The molar ratio of vinyldimethylfluorosilane to acrolein is 1:1.1.
[0042] The method for preparing electromagnetic shielding concrete in this embodiment is simple to operate. The following concrete raw materials are weighed according to their weight: 57 parts cement, 100 parts crushed stone, 52 parts sand, 13 parts fly ash, 17 parts water, 1 part fluorosilicone modified straw fiber and 2.5 parts functional additives. The mixture is stirred and mixed evenly at a speed of 200 rpm to obtain the electromagnetic shielding concrete.
[0043] Example 5
[0044] The electromagnetic shielding concrete of this embodiment is composed of the following key proportions of raw materials: 60 parts cement, 100 parts...
[0045] Crushed stone, 53 parts sand, 14 parts fly ash, 19 parts water, 2 parts fluorosilicone modified straw fiber, and 3 parts functional additives.
[0046] The functional additive is an organic-inorganic hybrid material of graphite coated with ferrocene-based MOF. Its preparation method is as follows: 250g of graphite oxide powder is uniformly dispersed in 1L of a 50% (w / w) ethanol aqueous solution by ultrasonication to obtain a graphite oxide mixture, which is then added to a hydrothermal reactor. 1,1'-ferrocene dicarboxylic acid, as the MOF organic ligand, is dissolved in DMF solvent to prepare a 20% (w / w) solution A. Nickel nitrate is dissolved in deionized water to prepare a nickel ion molar concentration B of 0.4 mol / L. Solutions A and B are added to the hydrothermal reactor at a certain feed rate, with a 1:2 molar ratio of 1,1'-ferrocene dicarboxylic acid to nickel nitrate. The reactor is refluxed at 110°C for 24 hours, allowing for molecular self-assembly on the graphite powder surface. After aging for 8 hours, a ferrocene-based MOF-coated graphite product with a network structure is obtained, which is the functional additive of this embodiment.
[0047] The modification method for the fluorosilicone-modified straw fiber is as follows: First, 180g of straw fiber is soaked in 500mL of a mixed solution of hydrogen peroxide and sulfuric acid (volume ratio 2:1) for 2 hours to activate it, obtaining hydroxyl-modified straw fiber. Then, an intermediate product obtained by the addition reaction of dimethyl(trifluoromethyl)vinylsilane and acrolein is added, and the two are reacted at 60℃ under the action of ammonium persulfate as an initiator. An 80% volume concentration ethanol solution is added to a high-pressure reactor, followed by hydroxyl-modified straw fiber and the intermediate product at a mass ratio of 10:2. The hydroxyl-modified straw fiber and the intermediate product undergo an aldol reaction to obtain fluorosilicone-modified straw fiber. The reaction pressure of the high-pressure reactor is set to 0.2MPa, and the reaction temperature is set to 75℃. The molar ratio of dimethyl(trifluoromethyl)vinylsilane to acrolein is 1:1.2.
[0048] The method for preparing electromagnetic shielding concrete in this embodiment is simple to operate. The following concrete raw materials are weighed according to their weight: 60 parts cement, 100 parts crushed stone, 53 parts sand, 14 parts fly ash, 19 parts water, 2 parts fluorosilicone modified straw fiber and 3 parts functional additives. The mixture is stirred and mixed evenly at a speed of 300 rpm to obtain the electromagnetic shielding concrete.
[0049] Example 6
[0050] The electromagnetic shielding concrete of this embodiment is composed of the following key proportions of raw materials: 64 parts cement, 100 parts...
[0051] Crushed stone, 54 parts sand, 13 parts fly ash, 17 parts water, 2 parts fluorosilicone modified straw fiber, and 4.5 parts functional additives.
[0052] The functional additive is an organic-inorganic hybrid material of graphite coated with ferrocene-based MOF. Its preparation method is as follows: 300g of graphite oxide powder is uniformly dispersed in 1L of a 50% (w / w) ethanol aqueous solution by ultrasonication to obtain a graphite oxide mixture, which is then added to a hydrothermal reactor. 1,1'-ferrocene dicarboxylic acid, as the MOF organic ligand, is dissolved in DMF solvent to prepare a 20% (w / w) solution A. Copper nitrate is dissolved in deionized water to prepare a copper ion molar concentration B of 0.6 mol / L. Solutions A and B are added to the hydrothermal reactor at a certain feed rate, with a 1:3 molar ratio of 1,1'-ferrocene dicarboxylic acid to copper nitrate. The reactor is refluxed at 105°C for 24 hours, allowing for molecular self-assembly on the graphite powder surface. After aging for 6 hours, a ferrocene-based MOF-coated graphite product with a network structure is obtained, which is the functional additive of this embodiment.
[0053] The modification method for the fluorosilicone-modified straw fiber is as follows: First, 210g of straw fiber is soaked in 500mL of a mixed solution of hydrogen peroxide and sulfuric acid (volume ratio 1:1) for 3 hours to activate it, thereby obtaining hydroxyl-modified straw fiber. Then, an intermediate product obtained by the addition reaction of vinyl(3,3,3-trifluoropropyl)dimethylsilane and acrolein is added, and the two react at 60℃ under the action of ammonium persulfate as an initiator. An 80% volume concentration ethanol solution is added to a high-pressure reactor, followed by the addition of hydroxyl-modified straw fiber and the intermediate product at a mass ratio of 10:3. The hydroxyl-modified straw fiber and the intermediate product undergo an aldol reaction to obtain fluorosilicone-modified straw fiber. The reaction pressure of the high-pressure reactor is set to 0.15MPa, and the reaction temperature is set to 80℃. The molar ratio of vinyl(3,3,3-trifluoropropyl)dimethylsilane to acrolein is 1:1.3.
[0054] The method for preparing electromagnetic shielding concrete in this embodiment is simple to operate. The following concrete raw materials are weighed according to their weight: 64 parts cement, 100 parts crushed stone, 54 parts sand, 13 parts fly ash, 17 parts water, 2 parts fluorosilicone modified straw fiber and 4.5 parts functional additives. The mixture is stirred and mixed evenly at a speed of 500 rpm to obtain the electromagnetic shielding concrete.
[0055] In the concrete raw materials of Examples 1 to 6 of this invention, the cement used is 42.5 grade ordinary Portland cement; the particle size of crushed stone is 5 to 20 mm, the particle size of sand is 1 to 3 mm, the particle size of fly ash is less than 50 μm, the particle size of graphite is 15 to 20 μm, and the length of straw fiber is 10 to 30 mm.
[0056] The concrete samples from Examples 1 to 6 were subjected to performance tests, and the results are shown in Table 1.
[0057] Compressive strength test: Referring to GB / T50081 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete", concrete samples were made into several standard test blocks with a side length of 100mm. After curing at room temperature for 28 days, the compressive strength was tested.
[0058] Permeability test: The permeability coefficient test of concrete samples was conducted in accordance with CJJ / T135-2009 "Technical Specification for Permeable Cement Concrete Pavement".
[0059] Electromagnetic shielding effectiveness test: The electromagnetic shielding concrete sample was prepared into a 3.6 mm specimen. The electromagnetic shielding transmission coefficient curve of the sample in the range of 600 MHz to 1 GHz was scanned using an impedance analyzer to measure the electromagnetic shielding effectiveness at 600 MHz and 1 GHz.
[0060] Table 1
[0061]
[0062]
[0063] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.
Claims
1. An electromagnetic shielding concrete, characterized in that, The concrete is composed of the following raw materials in parts by weight: 55-65 parts cement, 100 parts crushed stone, 50-55 parts sand, 12-15 parts fly ash, 16-20 parts water, 0.5-2.5 parts fluorosilicone modified straw fiber, and 1.5-5.5 parts functional additives; the functional additives are ferrocene-based MOF-coated graphite organic-inorganic hybrid materials; the ferrocene-based MOF uses ferrocene dicarboxylic acid as an organic ligand to form a network through molecular self-assembly reaction with metal ions in a hydrothermal reactor. The structure was obtained; the reaction conditions for the molecular self-assembly reaction were: reflux reaction at 90-120℃ for 12-24 hours; the modification method of the fluorosilicone modified straw fiber was as follows: the straw fiber was first activated by soaking it in a mixed solution of hydrogen peroxide and sulfuric acid for a period of time to obtain hydroxyl straw fiber; then an intermediate product obtained by the addition reaction of vinyl fluorosilane and acrolein was added, and the hydroxyl straw fiber and the intermediate product were reacted in a high-pressure reactor to obtain fluorosilicone modified straw fiber.
2. The electromagnetic shielding concrete as described in claim 1, characterized in that, The ferrocene dicarboxylic acid is 1,1'-ferrocene diboronic acid and / or 1,1'-ferrocene dicarboxylic acid.
3. The electromagnetic shielding concrete as described in claim 1, characterized in that, The metal ion is at least one of iron ion, nickel ion, and copper ion.
4. The electromagnetic shielding concrete as described in claim 1, characterized in that, The vinyl fluorosilane is at least one of vinyl dimethyl fluorosilane, dimethyl (trifluoromethyl) vinyl silane, and vinyl (3,3,3-trifluoropropyl) dimethyl silane.
5. The electromagnetic shielding concrete as described in claim 1, characterized in that, The molar ratio of vinyl fluorosilane to acrolein is 1:1 to 1.3; the mass ratio of hydroxyl straw fiber to intermediate product is 10:1 to 3.
6. A method for preparing electromagnetic shielding concrete as described in any one of claims 1 to 5, characterized in that, The preparation method is as follows: Weigh the following concrete raw materials by weight: 55-65 parts cement, 100 parts crushed stone, 50-55 parts sand, 12-15 parts fly ash, 16-20 parts water, 0.5-2.5 parts fluorosilicone modified straw fiber and 1.5-5.5 parts functional additives, and mix them evenly at a speed of 200-500 rpm to obtain the electromagnetic shielding concrete.