Modified solid waste recycled aggregate and preparation method thereof

Abstract

The application discloses a modified solid waste recycled aggregate and a preparation method thereof. The preparation method comprises the following steps: step 1: crushing waste concrete, then stirring at 60-70 DEG C for 30-40 min, washing with water, stirring at 60-70 DEG C for 30-40 min again, and washing with water to obtain pretreated recycled aggregate; and step 2: soaking the pretreated recycled aggregate in a modified solution for 8-10 h, and drying and solidifying to obtain the modified solid waste recycled aggregate. The application provides a modified solid waste recycled aggregate and a preparation method thereof. After waste concrete is crushed and pretreated, the modified solution containing modified montmorillonite, polysiloxane, polyvinyl alcohol, octyl triethoxysilane and other components is used for soaking and solidifying, so that the performance of the recycled aggregate is significantly improved.

Description

Technical Field

[0001] This invention belongs to the field of building materials technology, specifically relating to a modified solid waste recycled aggregate and its preparation method. Background Technology

[0002] In the field of building materials, recycled aggregates have received widespread attention in recent years as an important way to utilize waste concrete resources.

[0003] However, traditional recycled aggregates still have significant drawbacks in practical applications. Because waste concrete generates numerous microcracks and pores during the crushing process, recycled aggregates have high water absorption and poor interfacial bonding, severely impacting the mechanical properties and durability of concrete. Studies show that concrete made from untreated recycled aggregates typically has 15%-30% lower compressive strength than concrete made from natural aggregates, and its corrosion resistance in chloride-rich environments is significantly reduced. Currently used physical strengthening methods, such as mechanical grinding and heat treatment, can partially improve aggregate surface properties but cannot effectively seal internal pores. Conventional chemical modification techniques, often employing silane coupling agents or polymer impregnation, can enhance interfacial bonding but struggle to form a stable three-dimensional reinforcing network within the aggregate. Furthermore, existing modification processes often require complex equipment or are costly, hindering large-scale application. More importantly, most modification methods focus only on short-term strength improvement, neglecting long-term durability, leading to excessively rapid performance degradation of recycled aggregate concrete in humid or salt-corrosion environments.

[0004] Therefore, in order to solve the above problems, the present invention provides a modified solid waste recycled aggregate and its preparation method. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a modified solid waste recycled aggregate and its preparation method.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A method for preparing modified recycled solid waste aggregate includes the following steps:

[0008] Step 1: Crush the waste concrete, then stir it at 60-70℃ for 30-40 minutes, and rinse it with water; stir it again at 60-70℃ for 30-40 minutes, and rinse it with water to obtain pretreated recycled aggregate;

[0009] Step 2: Add the pretreated recycled aggregate to the modification solution and soak for 8-10 hours, then dry and solidify to obtain modified solid waste recycled aggregate.

[0010] More preferably, the modified solution comprises the following components: by weight, 8-10 parts modified montmorillonite, 5-6 parts polysiloxane, 40-50 parts polyvinyl alcohol, 70-80 parts deionized water, and 10-20 parts octyltriethoxysilane.

[0011] In a more optimized manner, the preparation process of the modified montmorillonite is as follows:

[0012] A1: Sodium-based montmorillonite was added to deionized water and pre-hydrated at room temperature for 24 hours. Then diallyl dimethyl ammonium chloride was added and ultrasonically dispersed at room temperature for 6-7 hours. After filtration, washing, drying and pulverizing, alkenylated montmorillonite was obtained.

[0013] A2: Under a protective atmosphere, alkenylated montmorillonite was added to deionized water and ultrasonically dispersed for 3-4 hours. Then, functional monomers, acrylic acid, and diallyl dimethyl ammonium chloride were added, and the pH was adjusted to 6-7. The mixture was stirred for 30 minutes, and then potassium persulfate solution was added. The mixture was reacted at 60-70°C for 6-7 hours. After the reaction was completed, the mixture was cooled to room temperature, washed, and dried to obtain modified montmorillonite.

[0014] In the process, sodium-based montmorillonite is prehydrated in deionized water and then undergoes ion exchange with diallyl dimethyl ammonium chloride (DA), allowing allyl quaternary ammonium salts to insert into the interlayer of montmorillonite, forming alkenylated montmorillonite. Subsequently, under a protective atmosphere, using potassium persulfate as an initiator, acrylic acid, functional monomers, and DA undergo a polymerization reaction in the interlayer to obtain modified montmorillonite.

[0015] In a more optimized manner, the raw materials for preparing the alkenyl montmorillonite include the following components: by weight, 5-10 parts sodium montmorillonite, 350-380 parts deionized water, and 24-25 parts diallyl dimethyl ammonium chloride.

[0016] In a more optimized manner, the raw materials for preparing the modified montmorillonite include the following components: by weight, 2-3 parts of alkenylated montmorillonite, 70-80 parts of deionized water, 12-15 parts of functional monomer, 8-10 parts of acrylic acid, 2-3 parts of diallyl dimethyl ammonium chloride, and 5-8 parts of potassium persulfate solution; wherein the mass fraction of potassium persulfate solution is 3 wt%.

[0017] In a more optimized manner, the preparation process of the functional monomer is as follows:

[0018] S1: Sodium bicarbonate, sodium azide, deionized water and tetrahydrofuran were mixed and added dropwise to glycidyl methacrylate. The mixture was stirred at room temperature for 72 h. The insoluble salt was removed by filtration. The solution was extracted with dichloromethane and the organic phase was dried with anhydrous sodium sulfate. The mixture was purified to obtain intermediate A.

[0019] S2: Under a protective atmosphere, intermediate A, 3-butynedic acid, deionized water and tetrahydrofuran were mixed and cooled to 0°C. Copper sulfate solution and sodium ascorbate solution were added dropwise and stirred at room temperature for 48 hours. After post-treatment, intermediate B was obtained.

[0020] S3: Under a protective atmosphere, intermediate B, sodium hydride, and 1,3-propanesulfonic acid lactone were mixed and stirred overnight at 50°C. The mixture was then filtered, washed, and dried to obtain the functional monomer.

[0021] In this scheme, sodium bicarbonate and sodium azide react in a tetrahydrofuran (THF) / water mixture to generate hydrogen azide, which then undergoes a nucleophilic ring-opening reaction with the epoxy group of glycidyl methacrylate (GMA) to form intermediate A containing an azide group and a hydroxyl group. The specific reaction process is shown below:

[0022]

[0023] In a more optimized manner, the raw materials for preparing intermediate A include the following components: by weight, 3-4 parts sodium bicarbonate, 3-4 parts sodium azide, 20-30 parts deionized water, 30-40 parts tetrahydrofuran, and 5-6 parts glycidyl methacrylate.

[0024] In the scheme, the azide group of intermediate A and the alkynyl group of 3-butynic acid are in Cu + Click chemistry occurs under catalysis (copper sulfate / sodium ascorbate reduction system) to generate a 1,2,3-triazole ring, yielding intermediate B. The specific reaction process is shown below:

[0025]

[0026] In a more optimized manner, the raw materials for preparing intermediate B include the following components: by weight, 1-2 parts intermediate A, 5-6 parts 3-butynedic acid, 50-60 parts deionized water, 80-90 parts tetrahydrofuran, 1-2 parts copper sulfate solution, and 3-4 parts sodium ascorbate solution; wherein the concentration of copper sulfate solution is 1 mol / L and the concentration of sodium ascorbate solution is 1 mol / L.

[0027] In this process, the hydroxyl group of intermediate B forms a sodium alkoxide under the action of sodium hydride, which then undergoes a nucleophilic substitution reaction with 1,3-propanesulfonic acid lactone to introduce a sulfonic acid group through ring opening, ultimately yielding a functional monomer containing methacrylate, a triazole ring, and a sulfonic acid group. The specific reaction process is shown below:

[0028]

[0029] In a more optimized manner, the raw materials for preparing the functional monomer include the following components: by weight, 2-3 parts intermediate B, 0.2-0.3 parts sodium hydride, and 1-2 parts 1,3-propanesulfonic acid lactone.

[0030] The beneficial effects of this invention are:

[0031] Firstly, the polymerization reaction occurring between the montmorillonite layers further introduces functional monomers containing methacrylate, triazole rings, sulfonic acid groups, and acrylic acid segments. The sulfonic acid groups of the functional monomers are highly polar, forming hydrogen or ionic bonds with the hydroxyl groups and calcium ions exposed on the pretreated surface of the recycled aggregate. The triazole ring, as a rigid heterocyclic structure, enhances intermolecular forces, while the carboxyl groups of the acrylic acid segments can undergo esterification with the hydroxyl groups on the aggregate surface to form covalent bonds. This effectively improves the strength loss problem caused by the porous surface and weak interface of traditional recycled aggregates. Simultaneously, the dense polymer network formed after intercalation polymerization acts as a physical barrier, effectively blocking the penetration paths of corrosive media such as moisture and chloride ions, thus improving the material's corrosion resistance.

[0032] Secondly, the interlayer polymer network of modified montmorillonite integrates multiple functional groups, forming a synergistic structure of "rigid skeleton-flexible segments." The 1,2,3-triazole ring in the functional monomer is generated by click chemistry, possessing extremely high chemical stability and rigidity, and can serve as a "micro-support" at the molecular level, enhancing the deformation resistance of the montmorillonite sheets. The long-chain structure formed by the copolymerization of acrylic acid and the methacrylate groups of the functional monomer has a certain degree of flexibility, and can disperse stress through chain segment creep under stress, reducing stress concentration. The montmorillonite sheets after intercalation polymerization can be exfoliated into nanoscale flakes in the modification solution, uniformly dispersed and attached to the surface and pores of recycled aggregate. Furthermore, polyvinyl alcohol and polysiloxane can penetrate into larger pores and the aggregate surface, ensuring the structural stability of the aggregate's large pores. This results in improved compressive and flexural strength of the aggregate. Detailed Implementation

[0033] 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.

[0034] Example 1: A method for preparing modified recycled solid waste aggregate, comprising the following steps:

[0035] Step 1: Crush the waste concrete, then stir it at 60°C for 30 minutes and rinse it with water; stir it again at 60°C for 30 minutes and rinse it with water to obtain pretreated recycled aggregate.

[0036] Step 2: Add the pretreated recycled aggregate to the modification solution and soak for 8 hours, then cure at 70°C for 12 hours to obtain modified solid waste recycled aggregate; the modification solution includes the following components: by weight, 8 parts modified montmorillonite, 5 parts polysiloxane, 40 parts polyvinyl alcohol, 70 parts deionized water, and 10 parts octyltriethoxysilane.

[0037] The preparation process of modified montmorillonite is as follows:

[0038] A1: Add 5 parts of sodium montmorillonite to 350 parts of deionized water and pre-hydrate at room temperature for 24 hours. Then add 24 parts of diallyl dimethyl ammonium chloride and ultrasonically disperse at room temperature for 6 hours. Filter, wash, dry and pulverize to obtain alkenylated montmorillonite.

[0039] A2: Under a protective atmosphere, 2 parts of alkenylated montmorillonite were added to 70 parts of deionized water and ultrasonically dispersed for 3 hours. Then, 12 parts of functional monomer, 8 parts of acrylic acid, and 2 parts of diallyl dimethyl ammonium chloride were added, the pH was adjusted to 6, and the mixture was stirred for 30 minutes. Then, 5 parts of potassium persulfate solution (mass fraction 3 wt%) were added, and the mixture was reacted at 60°C for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, washed, and dried to obtain modified montmorillonite.

[0040] The preparation process of the functional monomer is as follows:

[0041] S1: Mix 3 parts sodium bicarbonate, 3 parts sodium azide, 20 parts deionized water, and 30 parts tetrahydrofuran. Add 5 parts glycidyl methacrylate dropwise. Stir the mixture at room temperature for 72 hours. Filter to remove insoluble salts. Extract the solution with dichloromethane. Dry the organic phase with anhydrous sodium sulfate and purify to obtain intermediate A.

[0042] S2: Under a protective atmosphere, 1 part of intermediate A, 5 parts of 3-butynic acid, 50 parts of deionized water and 80 parts of tetrahydrofuran were mixed, cooled to 0°C, and 1 part of copper sulfate solution and 3 parts of sodium ascorbate solution were added dropwise. The mixture was stirred at room temperature for 48 hours and then post-processed to obtain intermediate B.

[0043] S3: Under a protective atmosphere, 2 parts of intermediate B, 0.2 parts of sodium hydride, and 1 part of 1,3-propanesulfonic acid lactone were mixed and stirred overnight at 50°C. The mixture was then filtered, washed, and dried to obtain the functional monomer.

[0044] Example 2: A method for preparing modified recycled solid waste aggregate, comprising the following steps:

[0045] Step 1: Crush the waste concrete, then stir it at 65°C for 35 minutes and rinse it with water; stir it again at 65°C for 35 minutes and rinse it with water to obtain pretreated recycled aggregate.

[0046] Step 2: Add the pretreated recycled aggregate to the modification solution and soak for 9 hours, then cure at 70°C for 12 hours to obtain modified solid waste recycled aggregate; the modification solution includes the following components: by weight, 9 parts modified montmorillonite, 5.5 parts polysiloxane, 45 parts polyvinyl alcohol, 75 parts deionized water, and 15 parts octyltriethoxysilane.

[0047] The preparation process of modified montmorillonite is as follows:

[0048] A1: 7.5 parts of sodium montmorillonite were added to 365 parts of deionized water and pre-hydrated at room temperature for 24 hours. Then, 24.5 parts of diallyl dimethyl ammonium chloride were added and ultrasonically dispersed at room temperature for 6.5 hours. The mixture was then filtered, washed, dried, and pulverized to obtain alkenylated montmorillonite.

[0049] A2: Under a protective atmosphere, 2.5 parts of alkenylated montmorillonite were added to 75 parts of deionized water and ultrasonically dispersed for 3.5 h. Then, 13.5 parts of functional monomer, 9 parts of acrylic acid, and 2.5 parts of diallyl dimethyl ammonium chloride were added, the pH was adjusted to 6.5, and the mixture was stirred for 30 min. Then, 6.5 parts of potassium persulfate solution (mass fraction 3 wt%) were added, and the mixture was reacted at 65 °C for 6.5 h. After the reaction was completed, the mixture was cooled to room temperature, washed, and dried to obtain modified montmorillonite.

[0050] The preparation process of the functional monomer is as follows:

[0051] S1: Mix 3.5 parts sodium bicarbonate, 3.5 parts sodium azide, 25 parts deionized water, and 35 parts tetrahydrofuran. Add 5.5 parts glycidyl methacrylate dropwise. Stir the mixture at room temperature for 72 hours. Filter to remove insoluble salts. Extract the solution with dichloromethane. Dry the organic phase with anhydrous sodium sulfate and purify to obtain intermediate A.

[0052] S2: Under a protective atmosphere, 1.5 parts of intermediate A, 5.5 parts of 3-butynedic acid, 55 parts of deionized water and 85 parts of tetrahydrofuran were mixed and cooled to 0°C. 1.5 parts of copper sulfate solution and 3.5 parts of sodium ascorbate solution were added dropwise and stirred at room temperature for 48 hours. After post-treatment, intermediate B was obtained.

[0053] S3: Under a protective atmosphere, 2.5 parts of intermediate B, 0.25 parts of sodium hydride, and 1.5 parts of 1,3-propanesulfonic acid lactone were mixed and stirred overnight at 50°C. The mixture was then filtered, washed, and dried to obtain the functional monomer.

[0054] Example 3: A method for preparing modified recycled solid waste aggregate, comprising the following steps:

[0055] Step 1: Crush the waste concrete, then stir it at 70°C for 40 minutes and rinse it with water; stir it again at 70°C for 40 minutes and rinse it with water to obtain pretreated recycled aggregate.

[0056] Step 2: Add the pretreated recycled aggregate to the modification solution and soak for 10 hours, then cure at 70°C for 12 hours to obtain modified solid waste recycled aggregate; the modification solution includes the following components: by weight, 10 parts modified montmorillonite, 6 parts polysiloxane, 50 parts polyvinyl alcohol, 80 parts deionized water, and 20 parts octyltriethoxysilane.

[0057] The preparation process of modified montmorillonite is as follows:

[0058] A1: Add 10 parts of sodium montmorillonite to 380 parts of deionized water and pre-hydrate at room temperature for 24 hours. Then add 25 parts of diallyl dimethyl ammonium chloride and ultrasonically disperse at room temperature for 7 hours. Filter, wash, dry and pulverize to obtain alkenylated montmorillonite.

[0059] A2: Under a protective atmosphere, 3 parts of alkenylated montmorillonite were added to 80 parts of deionized water and ultrasonically dispersed for 4 hours. Then, 15 parts of functional monomer, 10 parts of acrylic acid, and 3 parts of diallyl dimethyl ammonium chloride were added, the pH was adjusted to 7, and the mixture was stirred for 30 minutes. Then, 8 parts of potassium persulfate solution (mass fraction 3 wt%) were added, and the mixture was reacted at 70°C for 7 hours. After the reaction was completed, the mixture was cooled to room temperature, washed, and dried to obtain modified montmorillonite.

[0060] The preparation process of the functional monomer is as follows:

[0061] S1: Mix 4 parts sodium bicarbonate, 4 parts sodium azide, 30 parts deionized water, and 40 parts tetrahydrofuran. Add 6 parts glycidyl methacrylate dropwise. Stir the mixture at room temperature for 72 hours. Filter to remove insoluble salts. Extract the solution with dichloromethane. Dry the organic phase with anhydrous sodium sulfate and purify to obtain intermediate A.

[0062] S2: Under a protective atmosphere, 2 parts of intermediate A, 6 parts of 3-butynic acid, 60 parts of deionized water and 90 parts of tetrahydrofuran were mixed, cooled to 0°C, and 2 parts of copper sulfate solution and 4 parts of sodium ascorbate solution were added dropwise. The mixture was stirred at room temperature for 48 hours and then post-processed to obtain intermediate B.

[0063] S3: Under a protective atmosphere, 3 parts of intermediate B, 0.3 parts of sodium hydride, and 2 parts of 1,3-propanesulfonic acid lactone were mixed and stirred overnight at 50°C. The mixture was then filtered, washed, and dried to obtain the functional monomer.

[0064] Comparative Example 1: No functional monomers are introduced; everything else is the same as in Example 3, as detailed below:

[0065] Step 1: Crush the waste concrete, then stir it at 70°C for 40 minutes and rinse it with water; stir it again at 70°C for 40 minutes and rinse it with water to obtain pretreated recycled aggregate.

[0066] Step 2: Add the pretreated recycled aggregate to the modification solution and soak for 10 hours, then cure at 70°C for 12 hours to obtain modified solid waste recycled aggregate; the modification solution includes the following components: by weight, 10 parts modified montmorillonite, 6 parts polysiloxane, 50 parts polyvinyl alcohol, 80 parts deionized water, and 20 parts octyltriethoxysilane.

[0067] The preparation process of modified montmorillonite is as follows:

[0068] A1: Add 10 parts of sodium montmorillonite to 380 parts of deionized water and pre-hydrate at room temperature for 24 hours. Then add 25 parts of diallyl dimethyl ammonium chloride and ultrasonically disperse at room temperature for 7 hours. Filter, wash, dry and pulverize to obtain alkenylated montmorillonite.

[0069] A2: Under a protective atmosphere, 3 parts of alkenylated montmorillonite were added to 80 parts of deionized water and ultrasonically dispersed for 4 hours. Then, 10 parts of acrylic acid and 3 parts of diallyl dimethyl ammonium chloride were added, the pH was adjusted to 7, and the mixture was stirred for 30 minutes. Then, 6 parts of potassium persulfate solution (mass fraction 3 wt%) were added, and the mixture was reacted at 70°C for 7 hours. After the reaction was completed, the mixture was cooled to room temperature, washed, and dried to obtain modified montmorillonite.

[0070] Comparative Example 2: Commercially available coarse aggregate was used.

[0071] Testing and experimentation:

[0072] 20 parts of aggregate obtained from the examples and comparative examples, 100 parts of cement, 20 parts of fine aggregate, 12 parts of fly ash, 15 parts of water-reducing agent, and 75 parts of deionized water were mixed to prepare concrete blocks. These blocks were then cured in clean water and brine (30% sodium chloride aqueous solution) to the specified age. The flexural strength of the concrete was tested using a concrete pressure testing machine. The flexural strength and corrosion resistance coefficient were used to characterize its resistance to chloride ion attack. The data obtained are shown in the table below.

[0073] Conclusion: This invention provides a modified solid waste recycled aggregate and its preparation method. By crushing and pretreating waste concrete, and then soaking and curing it in a modified solution containing modified montmorillonite, polysiloxane, polyvinyl alcohol, octyltriethoxysilane, etc., the performance of the recycled aggregate is significantly improved.

[0074] Experimental data show that the modified recycled aggregates prepared in Examples 1 to 3 achieved compressive strengths of 36.8 MPa, 36.5 MPa, and 37.1 MPa, respectively, and flexural strengths of 7.91 MPa, 7.89 MPa, and 7.98 MPa in a clean water environment, and 6.72 MPa, 6.79 MPa, and 6.94 MPa in a saline environment. Compared with Comparative Example 1 (without the introduction of functional monomers), the modified recycled aggregates showed an increase in compressive strength of 10.8% (from 33.4 MPa to 37.1 MPa), and increases in flexural strength of 30.6% (from 6.11 MPa to 7.98 MPa) and 16.4% (from 5.96 MPa to 6.94 MPa) in clean water and saline environments, respectively. Although the compressive strength (39.8 MPa) and flexural strength (7.84 MPa in clean water, 7.54 MPa in brine) of Comparative Example 2 (commercially available coarse aggregate) are slightly higher than those of the modified recycled aggregate, the recycled aggregate of this invention achieves resource conservation and environmental protection goals through the recycling of waste concrete, while maintaining performance close to that of natural aggregate. Furthermore, the introduction of functional monomers significantly improves the interfacial bonding strength and corrosion resistance of the aggregate, demonstrating their crucial role in the modification process.

[0075] In summary, this invention not only solves the problems of low strength and poor durability of recycled aggregates, but also provides a feasible technical solution for the efficient utilization of construction waste, with significant environmental and economic benefits.

[0076] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0077] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A method for preparing modified recycled solid waste aggregate, characterized in that, Includes the following steps: Step 1: Crush the waste concrete, then stir it at 60-70℃ for 30-40 minutes, and rinse it with water; Stir at 60-70℃ for 30-40 minutes, then rinse with water to obtain pretreated recycled aggregate; Step 2: Add the pretreated recycled aggregate to the modification solution and soak for 8-10 hours, then dry and solidify to obtain modified solid waste recycled aggregate; The modified solution comprises the following components by weight: 8-10 parts modified montmorillonite, 5-6 parts polysiloxane, 40-50 parts polyvinyl alcohol, 70-80 parts deionized water, and 10-20 parts octyltriethoxysilane. The preparation process of the modified montmorillonite is as follows: A1: Sodium-based montmorillonite was added to deionized water and pre-hydrated at room temperature for 24 hours. Then diallyl dimethyl ammonium chloride was added and ultrasonically dispersed at room temperature for 6-7 hours. After filtration, washing, drying and pulverizing, alkenylated montmorillonite was obtained. A2: Under a protective atmosphere, alkenylated montmorillonite was added to deionized water and ultrasonically dispersed for 3-4 hours. Then, functional monomers, acrylic acid, and diallyl dimethyl ammonium chloride were added, and the pH was adjusted to 6-7. The mixture was stirred for 30 minutes, and then potassium persulfate solution was added. The mixture was reacted at 60-70°C for 6-7 hours. After the reaction was completed, the mixture was cooled to room temperature, washed, and dried to obtain modified montmorillonite. The preparation process of the functional monomer is as follows: S1: Sodium bicarbonate, sodium azide, deionized water and tetrahydrofuran were mixed and added dropwise to glycidyl methacrylate. The mixture was stirred at room temperature for 72 h. The insoluble salt was removed by filtration. The solution was extracted with dichloromethane and the organic phase was dried with anhydrous sodium sulfate. The mixture was purified to obtain intermediate A. S2: Under a protective atmosphere, intermediate A, 3-butynedic acid, deionized water and tetrahydrofuran were mixed and cooled to 0°C. Copper sulfate solution and sodium ascorbate solution were added dropwise and stirred at room temperature for 48 hours. After post-treatment, intermediate B was obtained. S3: Under a protective atmosphere, intermediate B, sodium hydride, and 1,3-propanesulfonic acid lactone were mixed and stirred overnight at 50°C. The mixture was then filtered, washed, and dried to obtain the functional monomer.

2. The method for preparing modified solid waste recycled aggregate according to claim 1, characterized in that, The raw materials for preparing the alkenyl montmorillonite include the following components: by weight, 5-10 parts sodium montmorillonite, 350-380 parts deionized water, and 24-25 parts diallyl dimethyl ammonium chloride.

3. The method for preparing modified solid waste recycled aggregate according to claim 1, characterized in that, The raw materials for preparing the modified montmorillonite include the following components: by weight, 2-3 parts of alkenylated montmorillonite, 70-80 parts of deionized water, 12-15 parts of functional monomer, 8-10 parts of acrylic acid, 2-3 parts of diallyl dimethyl ammonium chloride, and 5-8 parts of potassium persulfate solution; wherein the mass fraction of potassium persulfate solution is 3 wt%.

4. The method for preparing modified solid waste recycled aggregate according to claim 1, characterized in that, The raw materials for preparing intermediate A include the following components: by weight, 3-4 parts sodium bicarbonate, 3-4 parts sodium azide, 20-30 parts deionized water, 30-40 parts tetrahydrofuran, and 5-6 parts glycidyl methacrylate.

5. The method for preparing modified solid waste recycled aggregate according to claim 1, characterized in that, The raw materials for preparing intermediate B include the following components: by weight, 1-2 parts intermediate A, 5-6 parts 3-butynedic acid, 50-60 parts deionized water, 80-90 parts tetrahydrofuran, 1-2 parts copper sulfate solution, and 3-4 parts sodium ascorbate solution; wherein the concentration of copper sulfate solution is 1 mol / L and the concentration of sodium ascorbate solution is 1 mol / L.

6. The method for preparing modified solid waste recycled aggregate according to claim 1, characterized in that, The raw materials for preparing the functional monomer include the following components: by weight, 2-3 parts intermediate B, 0.2-0.3 parts sodium hydride, and 1-2 parts 1,3-propanesulfonic acid lactone.

7. Modified recycled solid waste aggregate obtained by the preparation method of modified recycled solid waste aggregate according to any one of claims 1-6.

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