Dispersant for concrete accelerating setting agent, preparation method thereof, and concrete accelerating setting agent

Abstract

The present application discloses a dispersant for concrete accelerator, a preparation method thereof and a concrete accelerator. The preparation method of the dispersant comprises the following steps: mixing a first monomer, a second monomer and a third monomer and reacting them to obtain the dispersant; wherein the first monomer is selected from styrene-maleic anhydride copolymer and / or styrene-acrylic acid copolymer, the second monomer is selected from ethylenediamine and / or triethylenetetramine, and the third monomer is selected from chitosan. The dispersant is applied to the concrete accelerator, can significantly improve the rheological properties of the accelerator system, improve the Al 3+ The dispersion and content in the accelerator ensure that the accelerator system has the optimal setting time, while ensuring that the concrete after solidification has sufficiently high strength and stability.

Description

Technical Field

[0001] The present application relates to a dispersant for a concrete accelerating agent, a preparation method thereof, and a concrete accelerating agent, and belongs to the technical field of concrete accelerating agents. Background Art

[0002] A concrete accelerator is a chemical admixture that causes cement or concrete to solidify quickly. It can also be used as a coagulant, shortening the time it takes for concrete slurry to coagulate and accelerating the setting and hardening rate of shotcrete. Concrete accelerators are primarily used in shotcrete construction in tunnels, urban construction, water conservancy and power culverts, diversion tunnels, industrial and mining construction, and other scenarios. They are also used in shotcrete support, leak prevention, and plugging for self-waterproofing structures, rapid ground concrete construction, and emergency concrete rescue projects. One of the keys to shotcrete technology is rapid early strength development. Shotcrete in the early stages of tunnel excavation plays a vital role in controlling surrounding rock deformation. Slow strength development not only affects construction progress but also exposes construction operators to the risk of insufficient support strength.

[0003] Ordinary quick-setting agents contain a large amount of alkaline substances. The introduction of alkaline substances will cause alkali aggregate damage to concrete. The high chlorine content will also accelerate the corrosion of steel bars, significantly reducing the later strength and durability of shotcrete. Although the current alkali-free quick-setting agents can improve the later strength and durability of shotcrete to a certain extent, in actual engineering applications, it is often difficult to achieve the high strength and durability required by the project, and the fluoride contained in them is extremely harmful to the human body and the environment. Currently, most of them are in the theoretical research stage and the market maturity is insufficient. In addition, since powdered quick-setting agents have serious dust during the construction process, which is not conducive to the health of people working in confined spaces, solid powders have begun to fade out of the market. The current alkali-free liquid quick-setting agents are mainly aluminum sulfate systems. However, due to the limited solubility and dispersibility of aluminum sulfate, the dosage of alkali-free liquid quick-setting agents is large during construction. Summary of the Invention

[0004] In order to solve the above problems, a dispersant for concrete accelerator and its preparation method and concrete accelerator are provided. The dispersant can enhance the organic complexation in the preparation process of the accelerator and optimize the rheological properties of the accelerator, and can improve the Al 3+ In addition, the present invention also prepares a low-viscosity, high-strength, chlorine-free, fluorine-free, and alkali-free accelerating setting agent system, which can improve the early strength of concrete and optimize the setting time.

[0005] According to one aspect of the present application, a dispersant for a concrete accelerating agent is provided, wherein the chemical structural formula of the dispersant is:

[0006]

[0007] wherein R1 is selected from an ethylenediamine group or a triethylenetetramine group, and R2 is selected from a maleic anhydride group or an acrylic acid group;

[0008] n is a positive integer between 1 and 10, m is a positive integer between 1 and 5, and p is a positive integer between 1 and 4.

[0009] Optionally, R1 is selected from ethylenediamine groups, and R2 is selected from maleic anhydride groups.

[0010] The dispersant is used in concrete accelerator, which can significantly improve the rheological properties of the accelerator system and enhance the Al 3+ The dispersion and content in the accelerator ensure that the accelerator system has the optimal setting time, while ensuring that the concrete after solidification has sufficiently high strength and stability.

[0011] According to another aspect of the present application, a method for preparing a dispersant for a concrete accelerating agent is provided, characterized in that it comprises the following steps:

[0012] The first monomer, the second monomer and the third monomer are mixed with an initiator and reacted to obtain the dispersant;

[0013] The first monomer is selected from styrene-maleic anhydride copolymer and / or styrene-acrylic acid copolymer, the second monomer is selected from ethylenediamine and / or triethylenetetramine, and the third monomer is selected from chitosan.

[0014] The styrene-maleic anhydride copolymer or styrene-acrylic acid copolymer in this application gives the dispersant good hydrophilicity through its polar groups (such as carboxyl groups and anhydride groups), which can stably disperse the aluminum salt precursor in an aqueous environment, prevent particle aggregation, and enhance the Al 3+ Dispersion effect in the aqueous phase. In addition, the styrene group provides a certain hydrophobicity, which makes the dispersant also have good dispersibility in oily media. The amino group of ethylenediamine or triethylenetetramine reacts chemically with the polar groups in the copolymer, enhancing the stability of the dispersant in the aqueous phase, improving the affinity with inorganic fillers, and providing the dispersant with the ability to bridge the aqueous phase and the oil phase, further enhancing its amphiphilic properties. Chitosan, as a natural polysaccharide, provides additional dispersibility and stability in aqueous environments due to its hydrophilicity and functional groups such as amino groups. At the same time, through its structure, it interacts with the components in the aqueous phase and the oil phase, thereby improving the stability and adaptability of the dispersant. In addition, chitosan can also play an antibacterial role. The synergistic effect of the three enables the dispersant to be effectively dispersed in both aqueous and oily systems, significantly improving the adaptability, stability and performance of the dispersant.

[0015] Optionally, the molar ratio of the first monomer, the second monomer and the third monomer is 0.05-0.2:0.05-0.2:1;

[0016] Preferably, the molar ratio of the first monomer, the second monomer and the third monomer is 0.1:0.1:1.

[0017] By controlling the molar ratio of these three monomers, the dispersant's hydrophilicity, lipophilicity, and stability can be precisely adjusted, thereby optimizing its performance. For example, increasing the proportion of styrene-maleic anhydride copolymer or styrene-acrylic acid copolymer improves the dispersant's hydrophilicity and dispersing ability; adjusting the proportion of ethylenediamine or triethylenetetramine helps enhance the dispersant's affinity for inorganic fillers and stability; and the proportion of chitosan determines the dispersant's thickening and aqueous stability. By precisely controlling the proportions of these monomers, the dispersant can be effectively dispersed in both aqueous and oily systems, improving its overall performance and adaptability in applications such as concrete accelerators.

[0018] Optionally, the first monomer is styrene-maleic anhydride copolymer, the second monomer is ethylenediamine, and the third monomer is chitosan.

[0019] Optionally, the reaction temperature is 120-170°C, preferably 140°C; the reaction time is not less than 2 hours, preferably 3 hours.

[0020] Optionally, the preparation step of the styrene-maleic anhydride copolymer includes: mixing styrene, maleic anhydride or acrylic acid, and benzoyl peroxide and reacting them to obtain a styrene-maleic anhydride copolymer or a styrene-acrylic acid copolymer, and then performing alkaline hydrolysis to obtain the styrene-maleic anhydride copolymer or the styrene-acrylic acid copolymer.

[0021] Optionally, the molar ratio of styrene to maleic anhydride is 1-2:1, preferably 1.5:1.

[0022] According to another aspect of the present application, a concrete accelerating agent is provided, comprising the following components in parts by weight: 0.5-2 parts of a dispersant, 0.5-2 parts of a graphene derivative, 50-60 parts of an aluminum salt, 5-8 parts of an organic regulator, 2-3 parts of an inorganic salt, 4-7 parts of a complexing stabilizer substance, and 30-35 parts of water, wherein the dispersant is selected from the above-mentioned dispersant or the dispersant prepared by the above-mentioned preparation method.

[0023] Wherein, the organic regulator is a mixture of glycine and acrylic acid, and the complex stabilizer is selected from at least one of diethanolamine, dimethylethanolamine and isopropanolamine.

[0024] In this application, the aluminum salt added to the accelerator can accelerate the hydration reaction of cement, thereby promoting the rapid setting of concrete and improving the early strength of concrete. The graphene derivative as a reinforcing agent can not only enhance the strength and durability of concrete, but also further improve the rapid setting effect of the accelerator, and enhance the internal binding force of cement particles through its unique structure. The dispersant can significantly improve the dispersibility of aluminum salts, by increasing the Al 3+ The solubility of the organic regulator in the accelerator ensures the uniform distribution of aluminum ions in the cement paste, avoids the aggregation and unstable reaction of aluminum salts, and thus enhances the effect of the accelerator system. The organic regulator can effectively adjust the setting time of concrete, prevent the accelerator from solidifying too quickly, and ensure the controllability of construction operations. The inorganic salt regulation can adjust the rate of cement hydration reaction and enhance stability. The complex stabilizer forms a stable complex with the metal aluminum ion, avoids the aluminum ion from undergoing unstable reaction, prevents the precipitation of aluminum salts, maintains the uniform dispersion of aluminum ions in the solution, optimizes its role in the cement hydration process, and thus improves the reaction efficiency and long-term stability of the accelerator system. Water, as a solvent, participates in the hydration reaction and adjusts the workability and strength of the concrete. Through the synergistic effect of these components, the accelerator can improve the setting speed, strength and overall performance of the concrete while ensuring stability, meeting the needs of different projects.

[0025] The dispersant can significantly improve the dispersibility of aluminum salts through the interaction between its molecular structure and aluminum salts, thereby increasing the 3+ Solubility in the accelerator. Specifically, the polar groups in the dispersant interact with the aluminum ions or other components in the aluminum salt, enhancing the solubility of the aluminum salt, reducing the electrostatic attraction between the aluminum salt molecules, thereby preventing the aggregation or precipitation of the aluminum salt and improving its dispersibility in the cement paste. In addition, the amphiphilic structure of the dispersant can interact with polar molecules and oily or hydrophobic molecules in the aqueous phase. This property helps to reduce the cohesive force between the aluminum salt particles, allowing them to be evenly dispersed in the aqueous environment and maintain a stable colloidal state. In addition, the negatively charged dispersant reduces the attraction between the aluminum salt particles through electrostatic repulsion, further enhancing its dispersibility. This ensures the uniform distribution of aluminum ions in the cement paste, prevents aluminum salt aggregation, and enhances the effectiveness of the accelerator.

[0026] Optionally, it includes the following components in parts by weight: 1 part of dispersant, 1 part of graphene derivative, 55 parts of aluminum salt, 6 parts of organic regulator, 2.5 parts of inorganic salt, 5.5 parts of complex stabilizer, and 30 parts of water.

[0027] Optionally, the aluminum salt is aluminum sulfate, the organic regulator is a mixture of glycine and acrylic acid in a mass ratio of 0.5-1:1, the complex stabilizer is a mixture of diethanolamine, dimethylethanolamine and isopropanolamine in a mass ratio of 1-2:10:2-3, and the inorganic salt is calcium sulfate and / or ferric sulfate.

[0028] Optionally, the graphene derivative can be graphene oxide or graphene, preferably graphene oxide, so as to further ensure the dispersibility of the graphene derivative in the accelerator system and ensure that it can be evenly dispersed. Since graphene oxide has a unique two-dimensional nanostructure and rich surface functional groups, it can fill 10-100nm-level capillaries and optimize the pore structure distribution. For example, the proportion of harmful pores (>50nm) can be reduced by 50%, forming a dense matrix. In addition, the oxygen-containing functional groups on the surface of graphene oxide can attract Ca 2 +, induces the directional growth of CSH gel to form high-density hydration products, thereby significantly improving the compressive and flexural strength of concrete. Graphene oxide can physically block Cl - 、SO4 2- Equi-corrosive ion migration pathways improve concrete durability.

[0029] The organic regulator of the present application can regulate the setting time and prevent excessive solidification. Glycine in the organic regulator is an amino acid that can react with calcium ions in cement particles through its amino group to inhibit the excessive hydration reaction of cement. Acrylic acid, on the other hand, has strong hydrophilicity and weak acidity and can form a stable complex by combining with calcium ions in cement, thereby regulating the rate of the hydration reaction. The mixture of glycine and acrylic acid works synergistically, effectively slowing down the initial stage of cement hydration, improving the construction operation time of concrete, avoiding strength loss and cracking problems caused by excessive solidification, and ensuring the stability and construction quality of concrete under different environmental conditions.

[0030] The complex stabilizer disclosed herein can prevent unstable reactions. The diethanolamine, dimethylethanolamine, and isopropanolamine in the complex stabilizer form stable complexes with aluminum ions via amino or hydroxyl groups, enhancing the dispersibility and stability of the aluminum ions, preventing adverse reactions, and improving the overall performance of the accelerator. Furthermore, these complex stabilizers regulate the activity of the aluminum ions, optimizing the cement hydration reaction rate and ensuring the long-term effectiveness and efficient setting of the accelerator.

[0031] The beneficial effects of this application include but are not limited to:

[0032] 1. The dispersant of the present application is used in concrete accelerators to significantly improve the rheological properties of the accelerator system and enhance the Al 3+The dispersion and content in the accelerator ensure that the accelerator system has the optimal setting time, while ensuring that the concrete after solidification has sufficiently high strength and stability.

[0033] 2. According to the dispersant of the present application, the synergistic effect of styrene-maleic anhydride copolymer, ethylenediamine and chitosan enables the dispersant to be effectively dispersed in both aqueous and oily systems, significantly improving the adaptability, stability and performance of the dispersant.

[0034] 3. According to the accelerator of the present application, the dispersant can be evenly dispersed therein, thereby improving the reaction efficiency and long-term stability of the accelerator system, while optimizing the setting time of concrete, improving the early strength of concrete, and ensuring the stability and overall performance of concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0036] Figure 1 This is a SEM image of a concrete sample after solidification when the quick-setting agent of Example 1 of the present application is used;

[0037] Figure 2 This is a SEM image of a concrete sample after solidification when the commercially available quick-setting agent of Comparative Example D9 of this application is used.

[0038] Figure 3 This is a state diagram of the quick-setting agent of some examples in this application after being placed for 1 week. DETAILED DESCRIPTION

[0039] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0040] Unless otherwise specified, the raw materials and catalysts in the examples of this application were purchased from commercial sources.

[0041] Example 1

[0042] The preparation steps of dispersant 1# are as follows:

[0043] (1) Styrene and maleic anhydride at a molar ratio of 1.5:1 were uniformly mixed, and the mixture was heated to 80°C for 1 hour under the initiation of benzoyl peroxide. After cooling, the product was filtered and vacuum-dried at 60°C to obtain a styrene-maleic anhydride copolymer;

[0044] (2) Styrene-maleic anhydride copolymer, ethylenediamine and chitosan in a molar ratio of 0.1:0.1:1 were mixed uniformly, heated to 140° C. and reacted for 3 hours to obtain dispersant 1#;

[0045] The chemical structure of dispersant 1# is:

[0046]

[0047] n is a positive integer between 1 and 10, m is a positive integer between 1 and 5, and p is a positive integer between 1 and 4;

[0048] The preparation steps of accelerator 1# are as follows:

[0049] Take 1 g of dispersant 1#, 1 g of graphene oxide, 55 g of aluminum sulfate, 2 g of glycine, 4 g of acrylic acid, 2.5 g of calcium sulfate, 0.8 g of diethanolamine, 4 g of dimethylethanolamine, 1.2 g of isopropanolamine and 30 g of water and stir continuously for 18 hours to obtain accelerating setting agent 1#.

[0050] Example 2#

[0051] The preparation steps of dispersant 2# are as follows:

[0052] (1) Styrene and acrylic acid at a molar ratio of 1.5:1 were uniformly mixed, and the mixture was heated to 80° C. for reaction for 1 h under the initiation of benzoyl peroxide. After cooling, the product was filtered and vacuum dried at 60° C. to obtain a styrene-acrylic acid copolymer;

[0053] (2) Styrene-acrylic acid copolymer, triethylenetetramine and chitosan in a molar ratio of 0.1:0.1:1 were mixed uniformly, heated to 140°C and reacted for 3 hours to obtain dispersant 2#.

[0054] The preparation steps of accelerating setting agent 2# differ from those of accelerating setting agent 1# in that dispersant 1# is replaced by dispersant 2#, and the remaining steps are the same as those of accelerating setting agent 1#, to obtain accelerating setting agent 2#.

[0055] Example 3

[0056] The preparation steps of dispersant 3# are as follows:

[0057] (1) Styrene and maleic anhydride in a molar ratio of 1:1 were uniformly mixed, and the mixture was heated to 80°C for reaction for 1 hour under the initiation of benzoyl peroxide. After cooling, the product was filtered and vacuum dried at 60°C to obtain a styrene-maleic anhydride copolymer;

[0058] (2) Styrene-maleic anhydride copolymer, triethylenetetramine and chitosan in a molar ratio of 0.05:0.05:1 were mixed uniformly, heated to 140°C and reacted for 3 hours to obtain dispersant 3#.

[0059] The preparation steps of accelerating setting agent 3# differ from those of accelerating setting agent 1# in that dispersant 1# is replaced by dispersant 3#, and the remaining steps are the same as those of accelerating setting agent 1#, to obtain accelerating setting agent 3#.

[0060] Example 4

[0061] The preparation steps of dispersant 4# are as follows:

[0062] (1) Styrene and maleic anhydride in a molar ratio of 3:1 were uniformly mixed, and the mixture was heated to 80°C for 1 hour under the initiation of benzoyl peroxide. After cooling, the product was filtered and vacuum dried at 60°C to obtain a styrene-maleic anhydride copolymer;

[0063] (2) Styrene-maleic anhydride copolymer, triethylenetetramine and chitosan in a molar ratio of 0.2:0.2:1 were mixed uniformly, heated to 160°C and reacted for 4 hours to obtain dispersant 4#.

[0064] The preparation steps of accelerating setting agent 4# differ from those of accelerating setting agent 1# in that dispersant 1# is replaced by dispersant 4#, and the remaining steps are the same as those of accelerating setting agent 1# to obtain accelerating setting agent 4#.

[0065] Example 5

[0066] The preparation steps of accelerator 5# are as follows:

[0067] Take 2 g of dispersant 1#, 2 g of graphene oxide, 50 g of aluminum sulfate, 2.5 g of glycine, 5 g of acrylic acid, 2 g of calcium sulfate, 0.6 g of diethanolamine, 3 g of dimethylethanolamine, 0.9 g of isopropanolamine and 30 g of water and stir continuously for 18 hours to obtain accelerator 5#.

[0068] Example 6

[0069] The preparation steps of accelerator 6# are as follows:

[0070] Take 2 g of dispersant 1#, 2 g of graphene oxide, 50 g of aluminum sulfate, 3 g of glycine, 3 g of acrylic acid, 2 g of calcium sulfate, 0.6 g of diethanolamine, 3 g of dimethylethanolamine, 0.9 g of isopropanolamine and 30 g of water and stir continuously for 18 hours to obtain accelerator 6#.

[0071] Comparative Example D1

[0072] The preparation steps of accelerator D1# differ from those of accelerator 1# in that: in step (2), styrene-maleic anhydride copolymer and ethylenediamine at a molar ratio of 0.1:0.1 are uniformly mixed, heated to 160°C, and reacted for 4 hours to obtain dispersant D1#.

[0073] The preparation steps of accelerator D1# differ from those of accelerator 1# in that dispersant 1# is replaced with dispersant D1#, and the remaining steps are the same as those of accelerator 1# to obtain accelerator D1#.

[0074] Comparative Example D2

[0075] The preparation steps of accelerator D2# differ from those of accelerator 1# in that: in step (2), styrene-maleic anhydride copolymer and chitosan at a molar ratio of 0.1:1 are uniformly mixed, heated to 160°C, and reacted for 4 hours to obtain dispersant D2#.

[0076] The preparation steps of accelerator D2# differ from those of accelerator 1# in that dispersant 1# is replaced with dispersant D2#, and the remaining steps are the same as those of accelerator 1# to obtain accelerator D2#.

[0077] Comparative Example D3

[0078] The preparation steps of accelerator D3# differ from those of accelerator 1# in that dispersant 1# is not added. The remaining steps are the same as those of accelerator 1#, and accelerator D3# is obtained.

[0079] Comparative Example D4

[0080] The preparation steps of accelerator D4# differ from those of accelerator 1# in that no organic regulator is added. The remaining steps are the same as those of accelerator 1#, and accelerator D4# is obtained.

[0081] Comparative Example D5

[0082] The preparation steps of accelerator D5# differ from those of accelerator 1# in that no complexing stabilizer is added. The remaining steps are the same as those of accelerator 1#, and accelerator D5# is obtained.

[0083] Comparative Example D6

[0084] The preparation steps of accelerator D6# differ from those of accelerator 1# in that graphene oxide is not added. The remaining steps are the same as those of accelerator 1#, and accelerator D6# is obtained.

[0085] Comparative Example D7

[0086] The preparation steps of accelerator D7# are as follows:

[0087] Take 3 g of dispersant 1#, 0.3 g of graphene oxide, 70 g of aluminum sulfate, 5 g of glycine, 5 g of acrylic acid, 2 g of calcium sulfate, 0.6 g of diethanolamine, 3 g of dimethylethanolamine, 0.9 g of isopropanolamine and 30 g of water and stir continuously for 18 hours to obtain accelerator D7#.

[0088] Comparative Example D8

[0089] The preparation steps of accelerator D8# differ from those of accelerator 1# in that no dispersant and graphene oxide are added. The remaining steps are the same as those of accelerator 1#, and accelerator D8# is obtained.

[0090] Comparative Example D9

[0091] The quick-setting agent D9# is a commercially available quick-setting agent.

[0092] Experimental example

[0093] The strength properties of shotcrete incorporating the present invention's accelerators 1#-6# and D1#-D9# were tested in accordance with JGJ / T372-2016, "Technical Specifications for the Application of Shotcrete." The test results are shown in Table 1. The cement used in the tests was Conch P.042.5 cement, and the water reducer was a high-performance polycarboxylate water reducer produced by a partner. The accelerator dosage in the present invention was 8% of the cement mass.

[0094] Table 1

[0095]

[0096]

[0097] As can be seen from Table 1, in Example 1, by optimizing the ratio of the various components and adding dispersant 1#, the concrete is ensured to have appropriate initial and final setting times, while avoiding loss of cement strength due to excessive solidification, thereby ensuring the strength stability and construction quality of the concrete under different environments.

[0098] also, Figure 1 This is a SEM image of a concrete sample after solidification when using the quick-setting agent 1# in Example 1 of this application. Figure 2 This is an SEM image of a concrete sample after solidification using the commercially available accelerating setting agent D9# of comparative example D9 of the present application. As can be seen from the figure, due to the presence of graphene oxide and dispersant in accelerating setting agent 1#, the crystal phase of the concrete after solidification using accelerating setting agent 1# is very dense and ordered, so the compressive and flexural strengths of the concrete are higher, while the crystal phase of the concrete after solidification using the ordinary commercially available accelerating setting agent D9# is relatively loose and disordered.

[0099] Figure 3This is a picture of the accelerator in the present application after one week of storage. From left to right, they are accelerator D8# (no graphene oxide, no dispersant), accelerator D3# (no dispersant), accelerator D6# (no graphene oxide), and accelerator 1. As can be seen from the figure, the accelerator without the dispersant exhibits severe stratification, indicating that the components of the accelerator are not evenly dispersed in the solvent, and graphene agglomerates, indicating that the accelerator system without the dispersant is relatively unstable. However, after one week of storage, the accelerator with the dispersant still exhibits uniform dispersion, with no aggregation, and graphene oxide is evenly dispersed in the system, indicating that the dispersant can significantly improve the dispersibility of graphene oxide and aluminum salt, enhancing the long-term stability of the accelerator system.

[0100] The foregoing is merely an embodiment of the present application, and the scope of protection of the present application is not limited by these specific embodiments, but is determined by the claims of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. made within the technical ideas and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A concrete accelerating agent, characterized in that: The invention comprises the following components in parts by weight: 0.5-2 parts of a dispersant, 0.5-2 parts of a graphene derivative, 50-60 parts of an aluminum salt, 5-8 parts of an organic regulator, 2-3 parts of an inorganic salt, 4-7 parts of a complexing stabilizer substance, and 30-35 parts of water; wherein the organic regulator is a mixture of glycine and acrylic acid, and the complex stabilizer is selected from at least one of diethanolamine, dimethylethanolamine and isopropanolamine; The preparation method of the dispersant comprises the following steps: mixing the first monomer, the second monomer, and the third monomer and reacting them to obtain the dispersant; Wherein, the first monomer is selected from styrene-maleic anhydride copolymer and / or styrene-acrylic acid copolymer, the second monomer is selected from ethylenediamine and / or triethylenetetramine, and the third monomer is selected from chitosan; The molar ratio of the first monomer, the second monomer and the third monomer is 0.05-0.2:0.05-0.2:1; The reaction temperature is 120-170°C; the reaction time is not less than 2 hours.

2. The concrete accelerating agent according to claim 1, characterized in that The molar ratio of the first monomer, the second monomer and the third monomer is 0.1:0.1:

1.

3. The concrete accelerating agent according to claim 1, characterized in that The first monomer is styrene-maleic anhydride copolymer, the second monomer is ethylenediamine, and the third monomer is chitosan.

4. The concrete accelerating agent according to claim 1, characterized in that The preparation steps of the styrene-maleic anhydride copolymer and the styrene-acrylic acid copolymer include: mixing styrene, maleic anhydride or acrylic acid, and benzoyl peroxide and reacting the mixture to obtain the styrene-maleic anhydride copolymer or the styrene-acrylic acid copolymer; The molar ratio of styrene to maleic anhydride is 1-2:

1.

5. The concrete accelerating agent according to claim 1, characterized in that The preparation comprises the following components in parts by weight: 1 part of a dispersant, 1 part of a graphene derivative, 55 parts of an aluminum salt, 6 parts of an organic regulator, 2.5 parts of an inorganic salt, 6 parts of a complex stabilizer, and 30 parts of water.

6. The concrete accelerating agent according to claim 1, characterized in that The aluminum salt is aluminum sulfate, the organic regulator is a mixture of glycine and acrylic acid in a mass ratio of 0.5-1:1, the complex stabilizer is a mixture of diethanolamine, dimethylethanolamine and isopropanolamine in a mass ratio of 1-2:10:2-3, and the inorganic salt is selected from calcium sulfate and / or ferric sulfate.

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