A high-strength concrete material and a method for producing the same

Abstract

The application discloses a kind of high-strength concrete materials and preparation method thereof, it is related to concrete technical field.The high-strength concrete material prepared by the application, include Portland cement, coarse aggregate, fine aggregate, pure water, water reducing agent, modified polyacrylate emulsion, modified floating bead;The modified polyacrylate emulsion is obtained by the reaction of polyacrylate and 4-(dithiolane-3-yl) but-2-ketone;The modified floating bead is obtained by the reaction of floating bead containing octanoic acid after aminization by silane coupling agent and cage monomer;The cage monomer is obtained by the reaction of 2,4,6-tris(benzimidazole) trimethylbenzene and 2,4,6-tribromomethyl trimethylbenzene, and then by bromination reaction.The high-strength concrete material prepared by the application has high strength, anti-aging performance and antibacterial performance.

Description

Technical Field

[0001] This invention relates to the field of concrete technology, specifically to a high-strength concrete material and its preparation method. Background Technology

[0002] In modern construction engineering, high-strength concrete has achieved large-scale application across multiple fields as a core building material. This composite material system, formed by scientifically proportioning cementitious materials, high-quality aggregates, and functional additives, demonstrates irreplaceable advantages in major projects such as super high-rise buildings, cross-sea bridges, and deep-buried tunnels due to its superior mechanical properties and durability. Compared to traditional concrete, high-strength concrete can not only bear greater structural loads, but its dense microstructure can also effectively resist performance degradation in complex environments, significantly extending the building's lifespan while reducing total life-cycle maintenance costs.

[0003] Concrete exposed to complex environments for extended periods faces the risk of performance degradation, necessitating enhanced anti-aging properties. Under temperature fluctuations, traditional concrete is prone to microcracks; ultraviolet radiation accelerates the decomposition of organic components; and acid rain erosion leads to surface peeling. Microbial adhesion in humid environments triggers biocorrosion, requiring concrete to possess excellent antibacterial properties. Chloride ion penetration causes steel reinforcement corrosion, necessitating the development of chloride ion-resistant concrete. In marine engineering and coastal infrastructure construction, chloride ion corrosion has become a major threat to the safety of concrete structures. Chloride ions enter the concrete interior through capillary water absorption and diffusion; when the concentration reaches a critical value, it triggers the rupture of the steel reinforcement passivation film, leading to electrochemical corrosion. Therefore, endowing concrete with excellent anti-aging and antibacterial properties can extend its service life, making it better suited for various application scenarios. Summary of the Invention

[0004] The purpose of this invention is to provide a high-strength concrete material and its preparation method to solve the problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A method for preparing high-strength concrete material includes the following preparation steps:

[0007] (1) Polymerize acrylate monomers to obtain polyacrylate;

[0008] (2) A modified polyacrylate was obtained by reacting polyacrylate with 4-(dithiopentane-3-yl)but-2-one; the modified polyacrylate was then emulsified to obtain a modified acrylate emulsion.

[0009] (3) Reaction of benzimidazole and 2,4,6-tribromomethyltrimethylbenzene yields 2,4,6-tris(benzimidazole)trimethylbenzene; reaction of 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene yields a cage-like monomer precursor; bromination of the cage-like monomer precursor yields a cage-like monomer.

[0010] (4) Porous cenospheres were screened from fly ash cenospheres by water separation, and octanoic acid was added to the porous cenospheres by vacuuming to obtain pretreated cenospheres.

[0011] (5) Reaction of γ-aminopropyltriethoxysilane with pretreated cenospheres yields aminated cenospheres; reaction of aminated cenospheres with cage-like monomers yields modified cenospheres;

[0012] (6) Mix the following raw materials: silicate cement, coarse aggregate, fine aggregate, modified cenospheres, modified polyacrylate emulsion, and triphenylphosphine evenly, add pure water and stir to obtain a slurry; pour the slurry into a mold and vibrate to compact it to obtain high-strength concrete material.

[0013] As an optimization, the preparation method of polyacrylate in step (1) is as follows: weigh acrylate monomers, isopropanol, and azobisisobutyronitrile in a mass ratio of 1:(20-30):(0.01-0.02); mix 40%-50% of acrylate monomers, 20%-30% of azobisisobutyronitrile, and 60%-70% of isopropanol and heat to 70-80℃ and reflux and stir for 1-2 hours, then add the remaining acrylate monomers, isopropanol, and azobisisobutyronitrile, and continue stirring at 70-80℃ for 4-5 hours, cool to 50-60℃, add triethylamine to adjust the pH to 6-7, and continue the reaction for 30-40 minutes to obtain polyacrylate; the acrylate monomers are obtained by mixing acrylic acid, methyl methacrylate, and acrolein in a mass ratio of 1:(0.5-0.7):(0.2-0.3).

[0014] As an optimization, the preparation method of the modified acrylate emulsion in step (2) is as follows: at 0°C, polyacrylate, 4-(dithiopentane-3-yl)but-2-one, tetrahydrofuran, and 0.5M acetic anhydride solution are mixed in a mass ratio of 1:(0.4-0.6):(20-30):(4-5), heated to room temperature and stirred for 30-40 min, then heated to 60-70°C and refluxed for 6-8 h. After cooling to room temperature, the pH is adjusted to 3-4 with 1M hydrochloric acid, and the mixture is precipitated with cold methanol at 0-4°C, filtered, washed, and dried to obtain the modified polyacrylate. The modified polyacrylate, emulsifier, and pure water are mixed in a mass ratio of 1:(0.1-0.2):(20-30) at 50-60°C and emulsified by high-speed shearing at 5000 rpm for 20-30 min.

[0015] As an optimization, the preparation method of the cage-like monomer in step (3) is as follows: Weigh 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene in a molar ratio of 1:1; mix 2,4,6-tris(benzimidazole)trimethylbenzene and acetonitrile in a mass ratio of 1:(20-30) to obtain an imidazole solution; mix 2,4,6-tribromomethyltrimethylbenzene and acetonitrile in a mass ratio of 1:(20-30) to obtain a tribromomethyltrimethylbenzene solution; simultaneously add the imidazole solution and the tribromomethyltrimethylbenzene solution to acetonitrile at a dropping rate of 0.2 mL / min, with the volume of acetonitrile being 2-3 times the volume of the imidazole solution; after the dropping is completed, stir at room temperature for 10-12 h; after the reaction is completed, remove the solvent under reduced pressure, wash with acetone and pure water and dry to obtain the cage-like monomer precursor;

[0016] The cage-like monomer precursor was dissolved in water, and a saturated aqueous solution of ammonium hexafluorophosphate was added to precipitate the solid. The solid was then dissolved in acetonitrile at 15-20 times its mass. N-bromosuccinimide at 0.2-0.3 times its mass (by weight of the cage-like monomer precursor) was added in three portions, 10 minutes apart. The mixture was irradiated under a 100W UV lamp for 1-2 hours. The solution was then concentrated under reduced pressure to one-fifth of its original volume, and finally analyzed using a chloroform / methanol solution (V...). 氯仿 :V 甲醇 The precipitate was obtained from a 2:1 ratio of chloroform to methanol solution, followed by filtration and a chloroform / methanol solution (V... 氯仿 :V 甲醇 =2:1) ​​Wash and dry to obtain cage-like monomers.

[0017] As an optimization, the preparation method of 2,4,6-tris(benzimidazole)trimethylbenzene is as follows: benzimidazole and tetrahydrofuran are mixed at a mass ratio of 1:(20-30) to obtain an ethylene solution, potassium hydroxide of 0.4-0.6 times the mass of benzimidazole is added, and the mixture is stirred at room temperature for 4-5 hours. 2,4,6-tribromomethyltrimethylbenzene and tetrahydrofuran are mixed at a mass ratio of 1:(20-30) and added to the ethylene solution. The mixture is stirred at room temperature for 12 hours to obtain 2,4,6-tris(benzimidazole)trimethylbenzene; the molar ratio of benzimidazole to 2,4,6-tribromomethyltrimethylbenzene is 3:1.

[0018] As an optimization, the preparation method of the pretreated cenospheres in step (4) is as follows: the porous cenospheres are screened by water selection. The specific operation is as follows: the fly ash cenospheres are poured into water and stirred. The broken cenospheres will sink to the bottom under the action of gravity. After standing for 5 minutes, the suspended part is collected and transferred to a vacuum kettle. The vacuum is drawn to -0.095MPa and maintained for 10 minutes. Pure water is injected and the pressure is released to normal pressure. The suspended part is removed and the bottom cenospheres are collected as porous cenospheres. The porous cenospheres are vacuum dried at 80℃. The cenospheres and octanoic acid are weighed at a mass ratio of 1:(1.2-1.5). The cenospheres are placed in a vacuum kettle and the vacuum is drawn to -0.095MPa and maintained for 30-40 minutes. Under the condition of maintaining vacuum, octanoic acid at 50-60℃ is injected and the pressure is released to normal pressure. The octanoic acid is pressed into the pores. The vacuum-depressurization operation is repeated 3 times to obtain the pretreated cenospheres.

[0019] As an optimization, the preparation method of the modified cenospheres in step (5) is as follows: γ-aminopropyltriethoxysilane and 90wt% ethanol aqueous solution are mixed at a mass ratio of 1:(100-150), the pH is adjusted to 4 with acetic acid, and the mixture is stirred at room temperature for 1-2 hours. Cenospheres with a mass of 1-1.5 times that of γ-aminopropyltriethoxysilane are added, and the mixture is ultrasonically dispersed and stirred at 50-60℃ for 5-6 hours to obtain aminated cenospheres. Aminated cenospheres, cage-like monomers, N,N-dimethylformamide and triethylamine are ultrasonically mixed at a mass ratio of 1:(0.7-0.9):(100-150):(1-1.2), and the mixture is heated to 50-60℃ and reacted for 10-12 hours to obtain modified cenospheres.

[0020] As an optimization, the preparation method of the high-strength concrete in step (6) is as follows: weigh the following raw materials: silicate cement, coarse aggregate, fine aggregate, modified cenospheres, modified polyacrylate emulsion, and triphenylphosphine. Mix the above raw materials evenly, add water, and stir in a mixer to obtain a slurry. Pour the slurry into a mold and vibrate to compact it to obtain high-strength concrete material.

[0021] As an optimization, the raw materials are as follows: by mass parts, 100-200 parts silicate cement, 250-300 parts coarse aggregate, 100-150 parts fine aggregate, 30-50 parts modified cenospheres, 10-15 parts modified polyacrylate emulsion, 0.5-1.0 parts triphenylphosphine, and 60-80 parts water.

[0022] The present invention also provides a high-strength concrete material prepared by the above-described method for preparing high-strength concrete material.

[0023] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0024] The high-strength concrete material prepared by this invention comprises silicate cement, coarse aggregate, fine aggregate, pure water, modified polyacrylate emulsion, and modified cenospheres; the modified polyacrylate emulsion is obtained by reacting polyacrylate with 4-(dithiopentane-3-yl)but-2-one; the modified cenospheres are obtained by reacting octanoic acid-containing cenospheres with a silane coupling agent and a cage-like monomer; the cage-like monomer is obtained by reacting 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene, followed by a bromination reaction.

[0025] This technical solution significantly improves the overall performance of concrete through multiple chemical modifications and the synergistic effect of functional components. First, a polyacrylate with active aldehyde groups in its side chains is prepared by copolymerizing acrylic acid, methyl methacrylate, and acrolein. Then, a chalcone structure and a dithiopentane ring with antioxidant capabilities are introduced through ketone condensation with 4-(dithiopentane-3-yl)but-2-one. The resulting emulsion is then incorporated into concrete. During the construction phase (in the presence of triphenylphosphine), the dithiopentane ring undergoes ring-opening polymerization, forming an organic cross-linked network inside and on the surface of the concrete. This network, through its strong polar groups and tight binding with hydration products, significantly improves the material's fracture toughness and tensile / flexural strength, while its antioxidant properties effectively delay aging.

[0026] Secondly, the cage-like antibacterial monomer synthesized by quaternization of 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene imparts broad-spectrum antibacterial properties to the material. Its unique cavity can efficiently capture free chloride ions, enhancing its resistance to chloride salt corrosion. After bromination with N-bromosuccinimide, this monomer is covalently grafted with bromomethyl and surface-amino-treated cenospheres (water-selected porous cenospheres, vacuum-coated octanoic acid, and modified with silane coupling agents). The functionalized cenospheres have three functions: ① as a carrier of the cage-like antibacterial monomer, holding... ① It continuously inhibits microorganisms and fixes chloride ions; ② As an octanoic acid slow-release capsule, it effectively blocks water transport by controllably releasing hydrophobic components (octanoic acid carboxyl groups are adsorbed on the pore walls, and the hydrophobic long chains are oriented outward to form a hydrophobic layer), thereby significantly improving the impermeability and durability of concrete. The slow-release design also avoids the interference of direct addition of hydrophobic agents on hydration and mechanical properties; ③ The octanoic acid release process simultaneously promotes the improvement of cement hydration and pore structure refinement, optimizing matrix density; the physical filling effect of the cenospheres themselves also synergistically enhances the stability of the concrete structure. In summary, this technology achieves multi-functional integration of anti-aging, toughening and strengthening, antibacterial, chloride ion erosion resistance, and long-term hydrophobic impermeability, fundamentally improving the durability and mechanical properties of concrete. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] The silicate cement described in the following examples and comparative examples is P.O42.5; the fine aggregate is natural river sand with a fineness modulus of 3.0-2.4 and an average particle size of 0.35-0.50 mm; the coarse aggregate is machine-made limestone crushed stone with a particle size of 10-20 mm; and the fly ash cenospheres are from Gongyi Borun Refractory Materials Co., Ltd.

[0029] Example 1: A method for preparing a high-strength concrete material, the method comprising the following preparation steps:

[0030] (1) Weigh acrylate monomers, isopropanol, and azobisisobutyronitrile in a mass ratio of 1:20:0.01; mix 40% of acrylate monomers, 20% of azobisisobutyronitrile, and 60% of isopropanol and heat to 80°C and reflux for 2 hours. Then add the remaining acrylate monomers, isopropanol, and azobisisobutyronitrile and continue stirring at 80°C for 5 hours. Cool down to 60°C, add triethylamine to adjust the pH to 7, and continue the reaction for 40 minutes. After precipitation with ethanol, filter, wash, and dry, polyacrylate is obtained. The acrylate monomers are obtained by mixing acrylic acid, methyl methacrylate, and acrolein in a mass ratio of 1:0.5:0.2.

[0031] (2) At 0℃, polyacrylate, 4-(dithiopentane-3-yl)but-2-one, tetrahydrofuran, and 0.5M acetic anhydride solution were mixed at a mass ratio of 1:0.4:20:4. The mixture was heated to room temperature and stirred for 40 min. The mixture was then heated to 70℃ and refluxed for 8 h. After cooling to room temperature, the pH was adjusted to 4 with 1M hydrochloric acid. The mixture was then precipitated with methanol at 4℃, filtered, washed, and dried to obtain modified polyacrylate. Modified polyacrylate, emulsifier OP-10, and pure water were mixed at a mass ratio of 1:0.1:20 at 60℃ and emulsified by high-speed shearing at 5000 rpm for 30 min.

[0032] (3) Mix benzimidazole and tetrahydrofuran at a mass ratio of 1:20 to obtain an ethylene solution. Add potassium hydroxide at a mass ratio of 0.4 times that of benzimidazole and stir at room temperature for 4 h. Mix 2,4,6-tribromomethyltrimethylbenzene and tetrahydrofuran at a mass ratio of 1:20 and add it dropwise to the ethylene solution at a dropping rate of 0.4 mL / min. After the addition is completed, continue stirring at room temperature for 12 h. After the reaction is completed, remove the solvent under reduced pressure, wash with acetone and pure water and dry under vacuum to obtain 2,4,6-tris(benzimidazole)trimethylbenzene; the molar ratio of benzimidazole and 2,4,6-tribromomethyltrimethylbenzene is 3:1.

[0033] Weigh 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene in a molar ratio of 1:1; mix 2,4,6-tris(benzimidazole)trimethylbenzene and acetonitrile in a mass ratio of 1:20 to obtain an imidazole solution; mix 2,4,6-tribromomethyltrimethylbenzene and acetonitrile in a mass ratio of 1:20 to obtain a tribromomethyltrimethylbenzene solution; simultaneously add the imidazole solution and the tribromomethyltrimethylbenzene solution dropwise to acetonitrile at a dropping rate of 0.2 mL / min, with the volume of acetonitrile being twice the volume of the imidazole solution. After the addition is complete, stir at room temperature for 12 h. After the reaction is complete, remove the solvent under reduced pressure, wash with acetone and pure water, and dry to obtain a cage-like monomer precursor.

[0034] The cage-like monomer precursor was dissolved in water, and a saturated aqueous solution of ammonium hexafluorophosphate was added to precipitate the solid. The solid was then dissolved in acetonitrile at 15 times its mass. N-bromosuccinimide at 0.2 times its mass was added in three portions, 10 minutes apart. The mixture was irradiated under a 100W UV lamp for 2 hours. The solution was then concentrated under reduced pressure to one-fifth of its original volume and subjected to a chloroform / methanol solution (V... 氯仿 :V 甲醇 The precipitate was obtained from a 2:1 ratio of chloroform to methanol solution, followed by filtration and a chloroform / methanol solution (V... 氯仿 :V 甲醇 =2:1) ​​Washing and drying yields cage-like monomers;

[0035] (4) Screening porous cenospheres by water separation method. The specific operation is as follows: Pour fly ash cenospheres into water and stir. The broken cenospheres will sink to the bottom under the action of gravity. After standing for 5 minutes, collect the suspended part, transfer it to a vacuum kettle, evacuate to -0.095MPa, maintain for 10 minutes, inject pure water, depressurize to normal pressure, remove the suspended part, and collect the bottom cenospheres, which are porous cenospheres.

[0036] The porous cenospheres were vacuum dried at 80℃; cenospheres and octanoic acid were weighed at a mass ratio of 1:1.2, the cenospheres were placed in a vacuum autoclave, and the vacuum was drawn to -0.095MPa and maintained for 40min; under the vacuum condition, octanoic acid at 60℃ was injected, and the pressure was released to atmospheric pressure to force the octanoic acid into the pores; the vacuum-depressurization operation was repeated 3 times to obtain the pretreated cenospheres;

[0037] (5) Mix γ-aminopropyltriethoxysilane and 90wt% ethanol aqueous solution at a mass ratio of 1:100, adjust the pH to 4 with acetic acid, stir at room temperature for 2h, add γ-aminopropyltriethoxysilane with 1 times the mass of cenospheres, disperse by ultrasonication, stir at 50℃ for 6h, filter, wash and dry to obtain aminated cenospheres; mix aminated cenospheres, cage-like monomers, N,N-dimethylformamide and triethylamine at a mass ratio of 1:0.7:100:1 by ultrasonication, heat to 60℃ and react for 12h, cool to room temperature, add n-propylamine and stir for 20min, filter, wash and dry to obtain modified cenospheres;

[0038] (6) Weigh the following raw materials by mass: 100 parts silicate cement, 250 parts coarse aggregate, 100 parts fine aggregate, 30 parts modified cenospheres, 10 parts modified polyacrylate emulsion, and 0.5 parts triphenylphosphine. Mix the above raw materials evenly, add 60 parts water, and stir in a mixer for 10 minutes to obtain a slurry. Pour the slurry into a mold and vibrate to compact it to obtain high-strength concrete material.

[0039] Example 2: A method for preparing a high-strength concrete material, the method comprising the following preparation steps:

[0040] (1) Weigh acrylate monomers, isopropanol, and azobisisobutyronitrile in a mass ratio of 1:25:0.01; mix 45% acrylate monomers, 25% azobisisobutyronitrile, and 65% isopropanol and heat to 75°C and reflux for 1.5 h, then add the remaining acrylate monomers, isopropanol, and azobisisobutyronitrile, and continue stirring at 75°C for 4.5 h, cool to 22°C, add triethylamine to adjust the pH to 6.5, and continue reacting for 35 min. After precipitation with ethanol, filter, wash and dry to obtain polyacrylate; the acrylate monomers are obtained by mixing acrylic acid, methyl methacrylate, and acrolein in a mass ratio of 1:0.6:0.25.

[0041] (2) At 0℃, polyacrylate, 4-(dithiopentane-3-yl)but-2-one, tetrahydrofuran, and 0.5M acetic anhydride solution were mixed at a mass ratio of 1:0.5:25:4.5. The mixture was heated to room temperature and stirred for 35 min. The mixture was then heated to 65℃ and refluxed for 7 h. After cooling to room temperature, the pH was adjusted to 3.5 with 1M hydrochloric acid. The mixture was then precipitated with cold methanol at 3℃, filtered, washed, and dried to obtain modified polyacrylate. Modified polyacrylate, emulsifier OP-10, and pure water were mixed at a mass ratio of 1:0.15:25 at 55℃ and emulsified by high-speed shearing at 5000 rpm for 25 min.

[0042] (3) Mix benzimidazole and tetrahydrofuran at a mass ratio of 1:25 to obtain an ethylene solution. Add potassium hydroxide at a mass ratio of 0.5 times that of benzimidazole and stir at room temperature for 4.5 h. Mix 2,4,6-tribromomethyltrimethylbenzene and tetrahydrofuran at a mass ratio of 1:25 and add them dropwise to the ethylene solution at a dropping rate of 0.4 mL / min. After the addition is completed, continue stirring at room temperature for 12 h. After the reaction is completed, remove the solvent under reduced pressure, wash with acetone and pure water and dry under vacuum to obtain 2,4,6-tris(benzimidazole)trimethylbenzene; the molar ratio of benzimidazole and 2,4,6-tribromomethyltrimethylbenzene is 3:1.

[0043] Weigh 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene in a molar ratio of 1:1; mix 2,4,6-tris(benzimidazole)trimethylbenzene and acetonitrile in a mass ratio of 1:25 to obtain an imidazole solution; mix 2,4,6-tribromomethyltrimethylbenzene and acetonitrile in a mass ratio of 1:25 to obtain a tribromomethyltrimethylbenzene solution; simultaneously add the imidazole solution and the tribromomethyltrimethylbenzene solution dropwise to acetonitrile at a dropping rate of 0.2 mL / min, with the volume of acetonitrile being 2.5 times the volume of the imidazole solution. After the addition is complete, stir at room temperature for 11 h. After the reaction is complete, remove the solvent under reduced pressure, wash with acetone and pure water, and dry to obtain a cage-like monomer precursor.

[0044] The cage-like monomer precursor was dissolved in water, and a saturated aqueous solution of ammonium hexafluorophosphate was added to precipitate the solid. The solid was then dissolved in acetonitrile at 17 times its mass. N-bromosuccinimide at 0.25 times its mass was added in three portions at 10-minute intervals. After irradiation under a 100W UV lamp for 1.5 hours, the mixture was concentrated under reduced pressure to one-fifth of its original volume. The precipitate was then obtained by precipitating with chloroform / methanol solution (V chloroform:V methanol = 2:1), followed by filtration, washing with chloroform / methanol solution (V chloroform:V methanol = 2:1), and drying to obtain the cage-like monomer.

[0045] (4) Screening porous cenospheres by water separation method. The specific operation is as follows: Pour fly ash cenospheres into water and stir. The broken cenospheres will sink to the bottom under the action of gravity. After standing for 5 minutes, collect the suspended part, transfer it to a vacuum kettle, evacuate to -0.095MPa, maintain for 10 minutes, inject pure water, depressurize to normal pressure, remove the suspended part, and collect the bottom cenospheres, which are porous cenospheres.

[0046] The porous cenospheres were vacuum dried at 80℃; cenospheres and octanoic acid were weighed at a mass ratio of 1:1.3, the cenospheres were placed in a vacuum autoclave, and the vacuum was drawn to -0.095MPa and maintained for 35min; under the vacuum condition, octanoic acid at 55℃ was injected, and the pressure was released to atmospheric pressure to force the octanoic acid into the pores; the vacuum-depressurization operation was repeated 3 times to obtain the pretreated cenospheres;

[0047] (5) Mix γ-aminopropyltriethoxysilane and 90wt% ethanol aqueous solution at a mass ratio of 1:125, adjust the pH to 4 with acetic acid, stir at room temperature for 1.5h, add 1.3 times the mass of γ-aminopropyltriethoxysilane cenospheres, disperse by ultrasonication, stir at 55℃ for 5.5h, filter, wash and dry to obtain aminated cenospheres; mix aminated cenospheres, cage-like monomers, N,N-dimethylformamide and triethylamine at a mass ratio of 1:0.8:120:1.1 by ultrasonication, heat to 55℃ and react for 11h, cool to room temperature, add n-propylamine and stir for 20min, filter, wash and dry to obtain modified cenospheres;

[0048] (6) Weigh the following raw materials by mass: 150 parts silicate cement, 270 parts coarse aggregate, 120 parts fine aggregate, 40 parts modified cenospheres, 12 parts modified polyacrylate emulsion, and 0.7 parts triphenylphosphine. Mix the above raw materials evenly, add 70 parts water, and stir in a mixer for 20 minutes to obtain a slurry. Pour the slurry into a mold and vibrate to compact it to obtain high-strength concrete material.

[0049] Example 3: A method for preparing a high-strength concrete material, the method comprising the following preparation steps:

[0050] (1) Weigh acrylate monomers, isopropanol, and azobisisobutyronitrile in a mass ratio of 1:30:0.02; mix 50% of acrylate monomers, 30% of azobisisobutyronitrile, and 70% of isopropanol and heat to 70°C and reflux for 1 hour. Then add the remaining acrylate monomers, isopropanol, and azobisisobutyronitrile and continue stirring at 70°C for 4 hours. Cool down to 50°C, add triethylamine to adjust the pH to 6, and continue the reaction for 30 minutes. After precipitation with ethanol, filter, wash, and dry, polyacrylate is obtained. The acrylate monomers are obtained by mixing acrylic acid, methyl methacrylate, and acrolein in a mass ratio of 1:0.7:0.3.

[0051] (2) At 0℃, polyacrylate, 4-(dithiopentane-3-yl)but-2-one, tetrahydrofuran, and 0.5M acetic anhydride solution were mixed at a mass ratio of 1:0.6:30:5. The mixture was heated to room temperature and stirred for 30 min. The mixture was then heated to 60℃ and refluxed for 6 h. After cooling to room temperature, the pH was adjusted to 3 with 1M hydrochloric acid. The mixture was then precipitated with cold methanol at 0℃, filtered, washed, and dried to obtain modified polyacrylate. Modified polyacrylate, emulsifier OP-10, and pure water were mixed at a mass ratio of 1:0.2:30 at 50℃ and emulsified by high-speed shearing at 5000 rpm for 20 min.

[0052] (3) Mix benzimidazole and tetrahydrofuran at a mass ratio of 1:30 to obtain an ethylene solution. Add potassium hydroxide at a mass ratio of 0.6 times that of benzimidazole and stir at room temperature for 5 h. Mix 2,4,6-tribromomethyltrimethylbenzene and tetrahydrofuran at a mass ratio of 1:30 and add them dropwise to the ethylene solution at a dropping rate of 0.4 mL / min. After the addition is complete, continue stirring at room temperature for 12 h. After the reaction is complete, remove the solvent under reduced pressure, wash with acetone and pure water and dry under vacuum to obtain 2,4,6-tris(benzimidazole)trimethylbenzene; the molar ratio of benzimidazole and 2,4,6-tribromomethyltrimethylbenzene is 3:1.

[0053] Weigh 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene in a molar ratio of 1:1; mix 2,4,6-tris(benzimidazole)trimethylbenzene and acetonitrile in a mass ratio of 1:30 to obtain an imidazole solution; mix 2,4,6-tribromomethyltrimethylbenzene and acetonitrile in a mass ratio of 1:30 to obtain a tribromomethyltrimethylbenzene solution; simultaneously add the imidazole solution and the tribromomethyltrimethylbenzene solution dropwise to acetonitrile at a dropping rate of 0.2 mL / min, with the volume of acetonitrile being 3 times the volume of the imidazole solution. After the addition is complete, stir at room temperature for 10 h. After the reaction is complete, remove the solvent under reduced pressure, wash with acetone and pure water, and dry to obtain a cage-like monomer precursor.

[0054] The cage-like monomer precursor was dissolved in water, and a saturated aqueous solution of ammonium hexafluorophosphate was added to precipitate the solid. The solid was then dissolved in acetonitrile at 20 times its mass. N-bromosuccinimide at 0.3 times its mass was added in three portions, 10 minutes apart. The mixture was irradiated under a 100W UV lamp for 2 hours. The solution was then concentrated under reduced pressure to one-fifth of its original volume and subjected to a chloroform / methanol solution (V... 氯仿 :V 甲醇 The precipitate was obtained from a 2:1 ratio of chloroform to methanol solution, followed by filtration and a chloroform / methanol solution (V... 氯仿 :V 甲醇 =2:1) ​​Washing and drying yields cage-like monomers;

[0055] (4) Screening porous cenospheres by water separation method. The specific operation is as follows: Pour fly ash cenospheres into water and stir. The broken cenospheres will sink to the bottom under the action of gravity. After standing for 5 minutes, collect the suspended part, transfer it to a vacuum kettle, evacuate to -0.095MPa, maintain for 10 minutes, inject pure water, depressurize to normal pressure, remove the suspended part, and collect the bottom cenospheres, which are porous cenospheres.

[0056] The porous cenospheres were vacuum dried at 80℃; cenospheres and octanoic acid were weighed at a mass ratio of 1:1.5, the cenospheres were placed in a vacuum autoclave, and the vacuum was drawn to -0.095MPa and maintained for 30min; under the vacuum condition, octanoic acid at 50℃ was injected, and the pressure was released to atmospheric pressure to force the octanoic acid into the pores; the vacuum-depressurization operation was repeated 3 times to obtain the pretreated cenospheres;

[0057] (5) Mix γ-aminopropyltriethoxysilane and 90wt% ethanol aqueous solution at a mass ratio of 1:150, adjust the pH to 4 with acetic acid, stir at room temperature for 1 h, add 1.5 times the mass of γ-aminopropyltriethoxysilane cenospheres, disperse by ultrasonication, stir at 50℃ for 5 h, filter, wash and dry to obtain aminated cenospheres; mix aminated cenospheres, cage-like monomers, N,N-dimethylformamide and triethylamine at a mass ratio of 1:0.9:150:1.2 by ultrasonication, heat to 50℃ and react for 10 h, cool to room temperature, add n-propylamine and stir for 20 min, filter, wash and dry to obtain modified cenospheres;

[0058] (6) Weigh the following raw materials by mass: 200 parts silicate cement, 300 parts coarse aggregate, 150 parts fine aggregate, 50 parts modified cenospheres, 15 parts modified polyacrylate emulsion, and 1.0 part triphenylphosphine. Mix the above raw materials evenly, add 80 parts water, and stir in a mixer for 10 minutes to obtain a slurry. Pour the slurry into a mold and vibrate to compact it to obtain high-strength concrete material.

[0059] Comparative Example 1:

[0060] The difference between the preparation method of the high-strength concrete material in Comparative Example 1 and Example 2 is that the polyacrylate is not modified. Specifically, step (2) is modified as follows: the polyacrylate, emulsifier OP-10 and pure water are mixed at a mass ratio of 1:0.15:25 at 55°C and the modified acrylic emulsion is obtained by high-speed shear emulsification at a speed of 5000 rpm and an emulsification time of 25 min.

[0061] Comparative Example 2:

[0062] The difference between the preparation method of the high-strength concrete material in Comparative Example 2 and Example 2 is that the fly ash cenospheres are not modified. Specifically, steps (3)-(5) are omitted. Step (5) is modified as follows: Weigh the following raw materials by mass: 150 parts of silicate cement, 270 parts of coarse aggregate, 120 parts of fine aggregate, 40 parts of modified cenospheres, 12 parts of modified polyacrylate emulsion, and 0.7 parts of triphenylphosphine. Mix the above raw materials evenly, add 70 parts of water, and stir in a mixer for 20 minutes to obtain a slurry. Pour the slurry into a mold and vibrate to compact it to obtain the high-strength concrete material.

[0063] Comparative Example 3:

[0064] The difference between the preparation method of the high-strength concrete material in Comparative Example 3 and Example 2 is that the cage-like monomer is not prepared. Specifically, steps (3) and (5) are not included. Step (6) is modified as follows: Weigh the following raw materials by mass: 150 parts of silicate cement, 270 parts of coarse aggregate, 120 parts of fine aggregate, 40 parts of pretreated cenospheres, 12 parts of modified polyacrylate emulsion, and 0.7 parts of triphenylphosphine. Mix the above raw materials evenly, add 70 parts of water, and stir in a mixer for 20 minutes to obtain a slurry. Pour the slurry into a mold and vibrate to compact it to obtain the high-strength concrete material.

[0065] After curing, the concrete materials prepared in the above examples and comparative examples were tested. The curing conditions were as follows: the test blocks were placed in a standard curing room and cured in accordance with the standard GB / T50081-2019 "Standard for Physical and Mechanical Test Methods of Concrete" for 28 days.

[0066] Test Example 1:

[0067] Mechanical property testing: All concrete materials prepared in the comparative examples and embodiments were made into 100mm×100mm×100mm specimens; compressive strength was tested according to standard GB / T50081-2019. The results are shown in Table 1.

[0068] Anti-aging performance testing: All concrete materials prepared in the comparative examples and embodiments were made into 100mm×100mm×100mm specimens. The specimens were placed in an ultraviolet aging chamber for strong ultraviolet radiation according to standard JC / T 60005-2020. The conditions for strong ultraviolet radiation were: light intensity of 1160W / m², temperature of 80℃, and irradiation time of 300h. After irradiation, the compressive strength was tested according to the mechanical property testing methods, and the compressive strength retention rate was calculated. The results are shown in Table 1.

[0069] Chlorine resistance test: All concrete materials prepared in the comparative examples and embodiments were made into 100mm×100mm×100mm specimens. All surfaces of the concrete specimens, except for the exposed surfaces, were sealed with a 1mm thick layer of epoxy resin. After the epoxy resin had fully cured, the specimens were completely immersed in a 3% NaCl solution for 120 days. After immersion, the specimens were removed and dried in a 45℃ drying oven. The compressive strength was tested according to the mechanical property test methods, and the compressive strength retention rate was calculated. The results are shown in Table 1.

[0070] Table 1:

[0071] ;

[0072] A comparison of the experimental data of Examples 1-3 and Comparative Examples 1-3 in Table 1 reveals that the high-strength concrete material prepared by the present invention has good mechanical properties, anti-aging properties, and chlorine resistance.

[0073] By comparison, the compressive strength of Examples 1-3 is greater than that of Comparative Examples 1-3, and the compressive strength retention rate of Examples 1-3 is greater than that of Comparative Examples 1 and 3. This indicates that a polyacrylate with active aldehyde groups in the side chain is prepared by copolymerizing acrylic acid, methyl methacrylate, and acrolein. Then, a chalcone structure with antioxidant capabilities and dynamic disulfide bonds are introduced through ketone condensation with 4-(dithiopentane-3-yl)but-2-one. The emulsion formed after emulsification of this polyacrylate is incorporated into concrete. During the construction stage (in the presence of triphenylphosphine), the dithiopentane ring-opening polymerization forms an organic cross-linked network inside and on the surface of the concrete. This network, through the tight binding of strongly polar groups with hydration products, significantly improves the fracture toughness and tensile / flexural strength of the material, while its antioxidant properties effectively delay aging.

[0074] Secondly, the cage-like monomer synthesized from 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene has a unique cavity that can efficiently capture free chloride ions, improving its resistance to chloride salt corrosion. After bromination with N-bromosuccinimide, the monomer is covalently grafted with bromomethyl and surface-aminated cenospheres (water-selected porous cenospheres, vacuum-coated octanoic acid, and modified with silane coupling agents). The functionalized cenospheres function as octanoic acid slow-release capsules, effectively blocking moisture transport by controlling the release of hydrophobic components, thereby significantly improving the impermeability and durability of concrete.

[0075] Test Example 2:

[0076] Antibacterial performance testing:

[0077] Test method: The concrete materials prepared in the examples and comparative examples were crushed and filtered through a 0.08 mm standard sieve to obtain powder with a particle size of less than 0.08 mm. 2 g of powder was placed on a 1 cm diameter filter paper, which was then placed in a solid culture medium coated with bacterial solution and incubated at 37°C for 12 h. The bacterial strain was Staphylococcus aureus, and the size of the inhibition zone was measured. The results are shown in Table 2.

[0078] Table 2:

[0079] ;

[0080] A comparison of the experimental data from Examples 1-3 and Comparative Examples 1-3 in Table 2 reveals that the high-strength concrete material prepared by this invention has good antibacterial properties.

[0081] By comparison, the antibacterial rates of Examples 1-3 were greater than those of Comparative Example 2, indicating that the cage-like antibacterial monomer synthesized by quaternization of 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene imparts antibacterial properties to the material.

[0082] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a high-strength concrete material, characterized in that, The preparation steps include the following: (1) Polymerize acrylate monomers to obtain polyacrylate; (2) A modified polyacrylate was obtained by reacting polyacrylate with 4-(dithiopentane-3-yl)but-2-one; the modified polyacrylate was emulsified to obtain a modified polyacrylate emulsion. (3) Reaction of benzimidazole and 2,4,6-tribromomethyltrimethylbenzene yields 2,4,6-tris(benzimidazole)trimethylbenzene; reaction of 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene yields a cage-like monomer precursor; bromination of the cage-like monomer precursor yields a cage-like monomer. (4) Porous cenospheres were screened from fly ash cenospheres by water separation, and octanoic acid was added to the porous cenospheres by vacuuming to obtain pretreated cenospheres. (5) Reaction of γ-aminopropyltriethoxysilane with pretreated cenospheres yields aminated cenospheres; reaction of aminated cenospheres with cage-like monomers yields modified cenospheres; (6) Weigh the following raw materials: Silicate cement, coarse aggregate, fine aggregate, modified cenospheres, modified polyacrylate emulsion, and triphenylphosphine are mixed evenly, and pure water is added and stirred to obtain a slurry. The slurry is poured into a mold and vibrated to compact it, thus obtaining high-strength concrete material.

2. The method for preparing high-strength concrete material according to claim 1, characterized in that, The preparation method of polyacrylate in step (1) is as follows: weigh acrylate monomers, isopropanol, and azobisisobutyronitrile in a mass ratio of 1:(20-30):(0.01-0.02); mix 40%-50% of acrylate monomers, 20%-30% of azobisisobutyronitrile, and 60%-70% of isopropanol and heat to 70-80℃ and reflux and stir for 1-2 hours, then add the remaining acrylate monomers, isopropanol, and azobisisobutyronitrile, and continue stirring at 70-80℃ for 4-5 hours, cool to 50-60℃, add triethylamine to adjust the pH to 6-7, and continue the reaction for 30-40 minutes to obtain polyacrylate; the acrylate monomers are obtained by mixing acrylic acid, methyl methacrylate, and acrolein in a mass ratio of 1:(0.5-0.7):(0.2-0.3).

3. The method for preparing high-strength concrete material according to claim 1, characterized in that, The modified polyacrylate emulsion in step (2) is prepared as follows: at 0°C, polyacrylate, 4-(dithiopentane-3-yl)but-2-one, tetrahydrofuran, and 0.5M acetic anhydride solution are mixed in a mass ratio of 1:(0.4-0.6):(20-30):(4-5), heated to room temperature and stirred for 30-40 min, and then heated to 60-70°C and refluxed for 6-8 h to obtain modified polyacrylate; the modified polyacrylate, emulsifier, and pure water are mixed and sheared in a mass ratio of 1:(0.1-0.2):(20-30) at 50-60°C to obtain modified polyacrylate emulsion.

4. The method for preparing high-strength concrete material according to claim 1, characterized in that, The preparation method of the cage-like monomer in step (3) is as follows: Weigh 2,4,6-tris(benzimidazole)trimethylbenzene and 2,4,6-tribromomethyltrimethylbenzene at a molar ratio of 1:1; mix 2,4,6-tris(benzimidazole)trimethylbenzene and acetonitrile at a mass ratio of 1:(20-30) to obtain an imidazole solution; mix 2,4,6-tribromomethyltrimethylbenzene and acetonitrile at a mass ratio of 1:(20-30) to obtain a tribromomethyltrimethylbenzene solution; simultaneously add the imidazole solution and the tribromomethyltrimethylbenzene solution to acetonitrile, with the volume of acetonitrile being 2-3 times the volume of the imidazole solution; after the addition is completed, stir at room temperature for 10-12 hours; after the reaction is completed, remove the solvent under reduced pressure, wash with acetone and pure water, and dry to obtain the cage-like monomer precursor; The cage-like monomer precursor was dissolved in water, and a saturated aqueous solution of ammonium hexafluorophosphate was added to precipitate the solid. The solid was then dissolved in acetonitrile at 15-20 times its mass, and N-bromosuccinimide at 0.2-0.3 times its mass was added. After irradiation under a UV lamp for 1-2 hours, the cage-like monomer was obtained.

5. The method for preparing high-strength concrete material according to claim 4, characterized in that, The preparation method of the 2,4,6-tris(benzimidazole)trimethylbenzene is as follows: benzimidazole and tetrahydrofuran are mixed at a mass ratio of 1:(20-30) to obtain an ethylene solution, potassium hydroxide of 0.4-0.6 times the mass of benzimidazole is added, and the mixture is stirred at room temperature for 4-5 hours. 2,4,6-tribromomethyltrimethylbenzene and tetrahydrofuran are mixed at a mass ratio of 1:(20-30) and added to the ethylene solution. The mixture is stirred at room temperature for 12 hours to obtain 2,4,6-tris(benzimidazole)trimethylbenzene; the molar ratio of benzimidazole to 2,4,6-tribromomethyltrimethylbenzene is 3:

1.

6. The method for preparing high-strength concrete material according to claim 1, characterized in that, The preparation method of the pretreated cenospheres in step (4) is as follows: After screening the cenospheres with holes by water selection, weigh the cenospheres and octanoic acid at a mass ratio of 1:(1.2-1.5). Place the cenospheres in a vacuum vessel, evacuate to -0.095MPa, and maintain for 30-40 minutes. Under the condition of maintaining vacuum, inject octanoic acid at 50-60℃, depressurize to normal pressure, and press the octanoic acid into the holes to obtain the pretreated cenospheres.

7. The method for preparing high-strength concrete material according to claim 1, characterized in that, The modified cenospheres in step (5) are prepared as follows: γ-aminopropyltriethoxysilane and 90wt% ethanol aqueous solution are mixed at a mass ratio of 1:(100-150), the pH is adjusted to 4 with acetic acid, and the mixture is stirred at room temperature for 1-2 hours. Cenospheres with a mass of 1-1.5 times that of γ-aminopropyltriethoxysilane are added, and the mixture is ultrasonically dispersed and stirred at 50-60℃ for 5-6 hours to obtain aminated cenospheres. Aminated cenospheres, cage-like monomers, N,N-dimethylformamide, and triethylamine are ultrasonically mixed at a mass ratio of 1:(0.7-0.9):(100-150):(1-1.2), and the mixture is heated to 50-60℃ and reacted for 10-12 hours to obtain modified cenospheres.

8. The method for preparing high-strength concrete material according to claim 1, characterized in that, The preparation method of the high-strength concrete material in step (6) is as follows: weigh the following raw materials: silicate cement, coarse aggregate, fine aggregate, modified cenospheres, modified polyacrylate emulsion, and triphenylphosphine. Mix the above raw materials evenly, add water, and stir in a mixer to obtain a slurry. Pour the slurry into a mold and vibrate to compact it to obtain the high-strength concrete material.

9. The method for preparing high-strength concrete material according to claim 8, characterized in that, The raw materials are as follows, by mass: 100-200 parts silicate cement, 250-300 parts coarse aggregate, 100-150 parts fine aggregate, 30-50 parts modified cenospheres, 10-15 parts modified polyacrylate emulsion, 0.5-1.0 parts triphenylphosphine, and 60-80 parts water.

10. A high-strength concrete material prepared by the preparation method according to any one of claims 1-9.