Dispersant for crystal nucleus type early strength agent, crystal nucleus type early strength agent and preparation method

Abstract

The present invention relates to the technical field of building materials, and specifically to a dispersant for a crystal nucleus type early strength agent, a crystal nucleus type early strength agent and a preparation method. The dispersant for the crystal nucleus type early strength agent comprises the following raw materials in parts by weight: 1000-1600 parts of a polyether macromonomer, 30-60 parts of an unsaturated organic acid, 1000-1500 parts of water, 4-6 parts of a molecular weight regulator, 1-2 parts of a reducing agent, 5-15 parts of an oxidant, 5-27 parts of a cationic monomer, 20-55 parts of a complexing monomer, and 5-17 parts of an unsaturated phosphate ester. The dispersant of the present invention can improve the early strength performance of the crystal nucleus type early strength agent from the two aspects of reducing particle size and synergistic enhancement. Moreover, improving the early strength performance of the crystal nucleus type early strength agent can reduce the amount of the crystal nucleus type early strength agent used, thereby reducing the influence of the crystal nucleus type early strength agent on the later strength of the component, or even having no influence on the later strength of the component, so that the later strength of the component is stable.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials, and in particular to a dispersant for a crystal nucleus type early strength agent, a crystal nucleus type early strength agent and a preparation method thereof, and further to a dispersant for a crystal nucleus type early strength agent and a preparation method thereof, a crystal nucleus type early strength agent and a preparation method thereof. Background Art

[0002] With the rapid development of the building materials industry, prefabricated buildings have gradually occupied the market, and the industry's demand for precast concrete components is also increasing. However, due to the low temperature in winter, the strength of precast concrete components develops slowly, resulting in low early strength. On the one hand, this will affect the mold turnover rate, reduce component production efficiency, and delay construction progress. On the other hand, it will make precast concrete components prone to defects when demolding and lifting, which will reduce the later durability of precast concrete components.

[0003] At present, the early strength of precast concrete components can be improved by adding early strength agents, which can include chloride early strength agents, alkali metal salt early strength agents, sulfate early strength agents or organic early strength agents. However, chloride early strength agents can cause steel corrosion and affect the durability of precast concrete components; alkali metal salt early strength agents can increase the risk of alkali-aggregate reaction; sulfate early strength agents can reduce the working performance of fresh slurry; organic early strength agents have a high cost of use and are difficult to control in dosage. Too high a dosage can cause slow setting of concrete.

[0004] CSH-PCE early strength agent is a new type of nanocrystalline early strength agent, which can meet the requirements of prefabricated components without steam curing, rapid demoulding and good durability in the later stage. However, in the process of realizing the present invention, the inventors found that the CSH-PCE early strength agent in the related art has the problems of large particle size, poor early strength performance and poor stability of late strength. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the CSH-PCE crystal nucleus type early strength agent in the prior art, such as large particle size, poor early strength performance and poor later strength stability, thereby providing a dispersant for a crystal nucleus type early strength agent, a crystal nucleus type early strength agent and a preparation method.

[0006] To this end, the present invention provides a dispersant for a crystal nucleus type early strength agent, comprising the following raw materials in parts by weight:

[0007] 1000-1600 parts of polyether macromonomer, 30-60 parts of unsaturated organic acid, 1000-1500 parts of water, 4-6 parts of molecular weight regulator, 1-2 parts of reducing agent, 5-15 parts of oxidizing agent, 5-27 parts of cationic monomer and 20-55 parts of complexing monomer.

[0008] Optionally, the dispersant includes the following raw materials in parts by weight:

[0009] 1200-1600 parts of polyether macromonomer, 35-50 parts of unsaturated organic acid, 1200-1500 parts of water, 4.5-6 parts of molecular weight regulator, 1-2 parts of reducing agent, 7-14 parts of oxidizing agent, 8-25 parts of cationic monomer and 25-50 parts of complexing monomer.

[0010] Optionally, the complexing monomer is an unsaturated monomer containing nitrogen atoms and / or oxygen atoms, and the complexing monomer can be complexed with calcium ions and silicon ions;

[0011] Optionally, the complexing monomer is selected from at least one of 3-[[2-(methacryloyloxy)ethyl]dimethylammonium]propionate, 2-(methacryloyloxy)ethyl-2-(trimethylamino)ethyl phosphate, N,N-dimethyl-N-2-propenyl-2-propen-1-ammonium chloride and N,N'-bis(vinylsulfonylacetyl)ethylenediamine.

[0012] Optionally, the polyether macromonomer is selected from at least one of 4-hydroxybutyl vinyl ether, ethylene glycol monovinyl polyethylene glycol ether, isopentanol polyoxyethylene ether and methyl allyl alcohol polyoxyethylene ether;

[0013] The unsaturated organic acid is selected from acrylic acid and / or methacrylic acid;

[0014] The molecular weight regulator is selected from at least one of mercaptopropionic acid, thioglycolic acid and mercaptoethanol;

[0015] The reducing agent is selected from at least one of vitamin C, ferrous sulfate and bleaching agent;

[0016] The oxidant is selected from at least one of hydrogen peroxide, ammonium persulfate and potassium persulfate;

[0017] The cationic monomer is selected from methacryloyloxyethyl trimethyl ammonium chloride and / or dimethylaminoethyl acrylate methyl chloride salt.

[0018] The present invention also provides a method for preparing the above-mentioned dispersant, comprising the following operations:

[0019] (1) taking a portion of an unsaturated organic acid, a cationic monomer and a complexing monomer, and mixing them uniformly to prepare a first solution;

[0020] (2) taking a portion of water and a molecular weight regulator, mixing them uniformly to prepare a second solution;

[0021] (3) taking a portion of water and a reducing agent, mixing them evenly to prepare a third solution;

[0022] (4) taking the remaining water, the polyether macromonomer, the oxidant and the remaining unsaturated organic acid and mixing them uniformly to prepare a fourth solution;

[0023] (5) Add the first solution, the second solution and the third solution dropwise into the fourth solution and keep the temperature to react.

[0024] Optionally, the weight of the part of the unsaturated organic acid in operation (1) accounts for 50% to 75% of the total weight of the unsaturated organic acid, and the weight of the remaining unsaturated organic acid in operation (4) accounts for 25% to 50% of the total weight of the unsaturated organic acid. By adding the unsaturated organic acid to the fourth solution and controlling the amount of the unsaturated organic acid, the fourth solution has a suitable pH value, providing suitable reaction conditions for the reaction in operation (5), improving the reaction efficiency and reaction degree, and thus improving the quality of the dispersant product.

[0025] Optionally, in operation (5), the first solution is added for 60 to 90 minutes; the second solution is added for 90 to 120 minutes; the third solution is added for 90 to 120 minutes; the first solution is added for less than the second solution, and the second solution is added for less than the third solution. By controlling the addition time of each solution, the molecular weight of the reaction product is controlled to prepare a dispersant product with a suitable molecular weight.

[0026] Optionally, in operation (5), the conditions for the heat preservation reaction include: the reaction temperature is 13 to 20° C., and the reaction time is 0.5 to 1.5 h.

[0027] The present invention also provides a crystal nucleus type early strength agent, the raw material of which includes the above-mentioned dispersant.

[0028] Optionally, the raw materials of the crystal nucleus type early strength agent include 3-10wt% of the dispersant, 10-15wt% of a soluble calcium salt, 5-9wt% of a soluble silicon salt and the balance of water;

[0029] Optionally, the particle size of the crystal nucleus type early strength agent does not exceed 250nm;

[0030] Optionally, in the crystal nucleus type early strength agent, the molar ratio of calcium element to silicon element is (1-2):1;

[0031] Optionally, the soluble calcium salt is selected from at least one of calcium nitrate, calcium nitrite and calcium formate;

[0032] Optionally, the soluble silicon salt is selected from at least one of sodium silicate, sodium metasilicate and sodium fluorosilicate.

[0033] Optionally, the crystal nucleus type early strength agent of the present invention is a nano crystal nucleus type early strength agent (CSH-PCE crystal nucleus type early strength agent).

[0034] The present invention also provides a method for preparing the above-mentioned crystal nucleus type early strength agent, comprising the following operations:

[0035] (a) taking a portion of the dispersant, diluting it with water and adjusting the pH to 12 to 14 to obtain a dispersant aqueous solution;

[0036] (b) taking the remaining dispersant and mixing it with the silicate aqueous solution to obtain a dispersant-siliconate mixed aqueous solution;

[0037] (c) under stirring conditions at 30 to 80° C., within 8 to 24 hours, the calcium salt aqueous solution and the dispersant-silicon salt mixed aqueous solution are simultaneously dripped into the dispersant aqueous solution, and cooled to room temperature.

[0038] Optionally, the weight of the part of the dispersant in operation (a) accounts for 70% to 95% of the total weight of the dispersant;

[0039] Optionally, in operation (a), an alkali solution is used to adjust the pH, wherein the alkali solution is a sodium hydroxide aqueous solution, and the mass fraction of the sodium hydroxide is 1 to 35%;

[0040] Optionally, the mass fraction of the dispersant in the dispersant aqueous solution is 1-10%, the mass fraction of the soluble silicon salt in the silicon salt aqueous solution is 20-40%, and the mass fraction of the soluble calcium salt in the calcium salt aqueous solution is 40-70%.

[0041] The technical solution of the present invention has the following advantages:

[0042] 1. The dispersant for the crystal nucleus type early strength agent provided by the present invention contains a complexing monomer in its raw material, which increases the adsorption mode and adsorption site of the dispersant, so that the dispersant has a strong complexing adsorption effect, thereby having a strong dispersing performance. Specifically, the dispersant can act on the surface of the crystal nucleus type early strength agent raw material, increase the steric hindrance between the crystal nucleus type early strength agent raw materials, reduce the reaction rate between the crystal nucleus type early strength agent raw materials, avoid the particle size of the crystal nucleus type early strength agent particles being too large due to the too fast reaction rate, thereby preparing a nano-scale crystal nucleus type early strength agent; at the same time, the dispersant can also act on the surface of the crystal nucleus type early strength agent particles, effectively reduce the contact probability between the crystal nucleus type early strength agent particles, thereby effectively reducing the agglomeration phenomenon between the crystal nucleus type early strength agent particles, so that the crystal nucleus type early strength agent particles can maintain a smaller particle size, thereby enhancing the stability of the crystal nucleus type early strength agent, and avoiding the crystal nucleus type early strength agent from precipitating. Therefore, the dispersant can significantly reduce the particle size of the crystal nucleus type early strength agent particles, thereby improving the early strength performance of the crystal nucleus type early strength agent.

[0043] In addition, the raw materials of the dispersant also contain cationic monomers, which makes the dispersant itself have certain early strength properties. Therefore, the dispersant can synergistically enhance the early strength properties of the crystal nucleus type early strength agent, significantly improve the early strength of precast concrete components, especially the ultra-early strength within 24 hours, and has no adverse effect on the later strength of the components.

[0044] Therefore, the dispersant of the present invention can improve the early strength performance of the crystal nucleus type early strength agent from the two aspects of reducing particle size and synergistic enhancement. Moreover, improving the early strength performance of the crystal nucleus type early strength agent can reduce the usage of the crystal nucleus type early strength agent, thereby reducing the influence of the crystal nucleus type early strength agent on the later strength of the component, or even having no influence on the later strength of the component, thereby stabilizing the later strength of the component.

[0045] 2. The dispersant for the crystal nucleus type early strength agent provided by the present invention, based on the raw material characteristics of the crystal nucleus type early strength agent, specifically introduces an unsaturated complexing monomer containing nitrogen atoms and oxygen atoms, thereby introducing the adsorption groups of the dispersant and the crystal nucleus type early strength agent raw materials (calcium salts, silicon salts) and the crystal nucleus type early strength agent, significantly improving the adsorption of the dispersant and the crystal nucleus type early strength agent raw materials and the crystal nucleus type early strength agent, and then enhancing the dispersant The dispersing effect of the dispersant on the crystal nucleus type early strength agent raw materials and the crystal nucleus type early strength agent. The complexing monomer is adsorbed on calcium and silicon ions in the crystal nucleus type early strength agent raw material based on the complexation of the N and O atoms therein, and the contact probability of calcium salts and silicon salts is reduced by the steric hindrance of the polyether side chain, thereby reducing the reaction rate, and achieving the purpose of a small and controllable particle size of the crystal nucleus type early strength agent; the crystal nucleus type early strength agent particles may also agglomerate when contacting and colliding. The same principle is used to reduce the agglomeration of the crystal nucleus type early strength agent particles by using the steric hindrance of the dispersant, so that the crystal nucleus type early strength agent product is uniform, stable in storage, and does not precipitate or stratify.

[0046] 3. The crystal nucleus type early strength agent provided by the present invention has small and uniform particle size and strong early strength performance. It can significantly improve the early strength of the component with a small dosage and has little effect on the later strength of the component, so that the later strength of the component is stable. DETAILED DESCRIPTION

[0047] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0048] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0049] Example 1

[0050] This embodiment provides a dispersant for a crystal nucleus type early strength agent, which is prepared by the following method:

[0051] (1) 30 g of an unsaturated organic acid (acrylic acid), 20 g of a cationic monomer (methacryloyloxyethyl trimethylammonium chloride) and 45 g of a complexing monomer (3-[[2-(methacryloyloxy)ethyl] dimethylammonium] propionate) were mixed uniformly to prepare a first solution;

[0052] (2) taking 50 g of water and 5 g of a molecular weight regulator (mercaptopropionic acid), and mixing them uniformly to prepare a second solution;

[0053] (3) taking 50 g of water and 1.5 g of a reducing agent (vitamin C), and mixing them evenly to prepare a third solution;

[0054] (4) 1300 g of water and 1400 g of a polyether macromonomer (4-hydroxybutyl vinyl ether) were mixed evenly until completely dissolved, and then 13 g of an oxidant (hydrogen peroxide) and 15 g of an unsaturated organic acid (acrylic acid) were added and mixed evenly to prepare a fourth solution;

[0055] (5) The first solution, the second solution and the third solution are sequentially added dropwise to the fourth solution. After the addition is completed, the mixture is kept warm at 15° C. for 1 hour to obtain a dispersant for a nucleus-type early strength agent. The addition time of the first solution is 75 minutes, the addition time of the second solution is 100 minutes, and the addition time of the third solution is 110 minutes.

[0056] The dispersant for the crystal nucleus type early strength agent prepared in this embodiment includes the following raw materials in parts by weight: 1400 parts of a polyether macromonomer (4-hydroxybutyl vinyl ether), 45 parts of an unsaturated organic acid (acrylic acid), 1400 parts of water, 5 parts of a molecular weight regulator (mercaptopropionic acid), 1.5 parts of a reducing agent (vitamin C), 13 parts of an oxidizing agent (hydrogen peroxide), 20 parts of a cationic monomer (methacryloyloxyethyltrimethylammonium chloride), and 45 parts of a complexing monomer (3-[[2-(methacryloyloxy)ethyl]dimethylammonium]propionate).

[0057] Example 2

[0058] A dispersant for a crystal nucleus type early strength agent is prepared according to the method of Example 1, except that the amount of raw materials is adjusted so that the dispersant for a crystal nucleus type early strength agent prepared in this example includes the following raw materials in parts by weight: 1200 parts of a polyether macromonomer (4-hydroxybutyl vinyl ether), 50 parts of an unsaturated organic acid (acrylic acid), 1200 parts of water, 6 parts of a molecular weight regulator (mercaptopropionic acid), 1 part of a reducing agent (vitamin C), 14 parts of an oxidizing agent (hydrogen peroxide), 8 parts of a cationic monomer (methacryloyloxyethyltrimethylammonium chloride), and 50 parts of a complexing monomer (3-[[2-(methacryloyloxy)ethyl]dimethylammonium] propionate).

[0059] Example 3

[0060] A dispersant for a crystal nucleus type early strength agent is prepared according to the method of Example 1, except that the amount of raw materials is adjusted so that the dispersant for a crystal nucleus type early strength agent prepared in this example includes the following raw materials in parts by weight: 1600 parts of a polyether macromonomer (4-hydroxybutyl vinyl ether), 35 parts of an unsaturated organic acid (acrylic acid), 1500 parts of water, 4.5 parts of a molecular weight regulator (mercaptopropionic acid), 2 parts of a reducing agent (vitamin C), 7 parts of an oxidizing agent (hydrogen peroxide), 25 parts of a cationic monomer (methacryloyloxyethyltrimethylammonium chloride), and 25 parts of a complexing monomer (3-[[2-(methacryloyloxy)ethyl]dimethylammonium] propionate).

[0061] Example 4

[0062] A dispersant for a crystal nucleus type early strength agent is prepared according to the method of Example 1, except that the amount of raw materials is adjusted so that the dispersant for a crystal nucleus type early strength agent prepared in this example includes the following raw materials in parts by weight: 1000 parts of a polyether macromonomer (4-hydroxybutyl vinyl ether), 60 parts of an unsaturated organic acid (acrylic acid), 1000 parts of water, 6 parts of a molecular weight regulator (mercaptopropionic acid), 1 part of a reducing agent (vitamin C), 15 parts of an oxidizing agent (hydrogen peroxide), 5 parts of a cationic monomer (methacryloyloxyethyltrimethylammonium chloride), and 55 parts of a complexing monomer (3-[[2-(methacryloyloxy)ethyl]dimethylammonium] propionate).

[0063] Example 5

[0064] A dispersant for a crystal nucleus type early strength agent is prepared according to the method of Example 1, except that the amount of raw materials is adjusted so that the dispersant for a crystal nucleus type early strength agent prepared in this example includes the following raw materials in parts by weight: 1600 parts of a polyether macromonomer (4-hydroxybutyl vinyl ether), 30 parts of an unsaturated organic acid (acrylic acid), 1500 parts of water, 4 parts of a molecular weight regulator (mercaptopropionic acid), 2 parts of a reducing agent (vitamin C), 5 parts of an oxidizing agent (hydrogen peroxide), 27 parts of a cationic monomer (methacryloyloxyethyltrimethylammonium chloride), and 20 parts of a complexing monomer (3-[[2-(methacryloyloxy)ethyl]dimethylammonium] propionate).

[0065] Example 6

[0066] A dispersant for a crystal nucleus type early strength agent was prepared according to the method of Example 1, except that the polyether macromonomer used in this example was ethylene glycol monovinyl polyethylene glycol ether, the unsaturated organic acid was methacrylic acid, the molecular weight regulator was thioglycolic acid, the reducing agent was ferrous sulfate, the oxidant was ammonium persulfate, the cationic monomer was dimethylaminoethyl acrylate methyl chloride, and the complexing monomer was 2-(methacryloyloxy)ethyl-2-(trimethylamino)ethyl phosphate.

[0067] Comparative Example 1

[0068] The dispersant for early strength agent was prepared according to the method of Example 1, except that no complexing monomer was added during the preparation of the dispersant in this comparative example.

[0069] Examples 7-12

[0070] The dispersants prepared in Examples 1-6 were used in sequence to prepare a crystal nucleus type early strength agent according to the following method:

[0071] (a) taking 54 g of the dispersant, adding 647 g of water to dilute, and adjusting the pH to 12-14 with a 10% by mass sodium hydroxide aqueous solution to obtain an 8% by mass dispersant aqueous solution;

[0072] (b) taking 6 g of the dispersant and mixing it with 150 g of a 40% by mass silicate (sodium metasilicate) aqueous solution to obtain a dispersant-silicon salt mixed aqueous solution;

[0073] (c) Under stirring at 50° C., within 10 hours, 143 g of a 70% by mass calcium salt (calcium nitrate) aqueous solution and the dispersant-silicon salt mixed aqueous solution obtained in operation (b) were simultaneously added dropwise to the dispersant aqueous solution obtained in operation (a). After the addition was completed, the mixture was cooled to room temperature to obtain a crystal nucleus type early strength agent.

[0074] Comparative Example 2

[0075] An early strength agent was prepared according to the method of Example 7, except that the dispersant used in this comparative example was the dispersant prepared in Comparative Example 1.

[0076] Experimental Example 1

[0077] The average particle size of each early strength agent particle prepared in Examples 7-12 and Comparative Example 2 was measured by a nanoparticle size analyzer. The measurement results are shown in Table 1.

[0078] Table 1 Average particle size of each early strength agent particle

[0079]

[0080]

[0081] It can be seen from Table 1 that the use of the dispersant of the present invention can prepare a nano-scale crystal nucleus-type early strength agent with uniform particle size.

[0082] Experimental Example 2

[0083] The early strength agents prepared in Examples 7-12 and Comparative Example 2 were respectively used to prepare concrete test blocks according to the method described in GB 8076-2008, and the compressive strength ratios of the test blocks at 12h, 7th day and 28th day were respectively tested according to the method described in GB 8076-2008. The test results are shown in Table 2.

[0084] Table 2 Compressive strength ratio test results of each test block

[0085] Corresponding early strength agent 12h，％ 7 days, % 28 days, % Example 7 300 150 120 Example 8 290 140 115 Example 9 285 145 112 Example 10 280 135 110 Embodiment 11 270 135 106 Example 12 255 130 103 Comparative Example 2 170 105 90

[0086] It can be seen from Table 2 that the crystal nucleus type early strength agent of the present invention can significantly improve the early strength of precast concrete components, especially the ultra-early strength within 24 hours, and has no adverse effect on the later strength of the components.

[0087] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A dispersant for a crystal nucleus type early strength agent, characterized in that: The invention comprises the following raw materials in parts by weight: 1000-1600 parts of polyether macromonomer, 30-60 parts of unsaturated organic acid, 1000-1500 parts of water, 4-6 parts of molecular weight regulator, 1-2 parts of reducing agent, 5-15 parts of oxidizing agent, 5-27 parts of cationic monomer, 20-55 parts of complexing monomer; wherein the complexing monomer is selected from at least one of 3-[[2-(methacryloyloxy)ethyl]dimethylammonium]propionate and 2-(methacryloyloxy)ethyl-2-(trimethylamino)ethyl phosphate.

2. The dispersant according to claim 1, characterized in that The dispersant comprises the following raw materials in parts by weight: 1200-1600 parts of polyether macromonomer, 35-50 parts of unsaturated organic acid, 1200-1500 parts of water, 4.5-6 parts of molecular weight regulator, 1-2 parts of reducing agent, 7-14 parts of oxidizing agent, 8-25 parts of cationic monomer and 25-50 parts of complexing monomer.

3. The dispersant according to claim 1, characterized in that The polyether macromonomer is selected from at least one of 4-hydroxybutyl vinyl ether, ethylene glycol monovinyl polyethylene glycol ether, isopentanol polyoxyethylene ether and methyl allyl alcohol polyoxyethylene ether; The unsaturated organic acid is selected from acrylic acid and / or methacrylic acid; The molecular weight regulator is selected from at least one of mercaptopropionic acid, thioglycolic acid and mercaptoethanol; The reducing agent is selected from at least one of vitamin C, ferrous sulfate and bleaching agent; The oxidant is selected from at least one of hydrogen peroxide, ammonium persulfate and potassium persulfate; The cationic monomer is selected from methacryloyloxyethyl trimethyl ammonium chloride and / or dimethylaminoethyl acrylate methyl chloride.

4. A method for preparing the dispersant according to any one of claims 1 to 3, characterized in that: The following operations are included: (1) taking a portion of an unsaturated organic acid, a cationic monomer and a complexing monomer, and mixing them uniformly to prepare a first solution; (2) taking a portion of water and a molecular weight regulator, mixing them uniformly to prepare a second solution; (3) taking a portion of water and a reducing agent, mixing them evenly to prepare a third solution; (4) taking the remaining water, the polyether macromonomer, the oxidant and the remaining unsaturated organic acid and mixing them uniformly to prepare a fourth solution; (5) Add the first solution, the second solution and the third solution dropwise into the fourth solution and keep the temperature to react.

5. The method according to claim 4, characterized in that The weight of the part of the unsaturated organic acid in operation (1) accounts for 50% to 75% of the total weight of the unsaturated organic acid, and the weight of the remaining unsaturated organic acid in operation (4) accounts for 25% to 50% of the total weight of the unsaturated organic acid; Optionally, in operation (5), the first solution is added for 60 to 90 minutes; the second solution is added for 90 to 120 minutes; the third solution is added for 90 to 120 minutes; the first solution is added for less than the second solution, and the second solution is added for less than the third solution; Optionally, in operation (5), the conditions for the heat preservation reaction include: the reaction temperature is 13 to 20° C., and the reaction time is 0.5 to 1.5 h.

6. A crystal nucleus type early strength agent, characterized in that: The raw material of the crystal nucleus type early strength agent includes the dispersant according to any one of claims 1 to 4.

7. The crystal nucleus type early strengthening agent according to claim 6, characterized in that: The raw materials of the crystal nucleus type early strength agent include 3-10wt% of the dispersant, 10-15wt% of soluble calcium salt, 5-9wt% of soluble silicon salt and the balance of water; Optionally, the particle size of the crystal nucleus type early strength agent does not exceed 250nm; Optionally, in the crystal nucleus type early strength agent, the molar ratio of calcium element to silicon element is (1-2):1; Optionally, the soluble calcium salt is selected from at least one of calcium nitrate, calcium nitrite and calcium formate; Optionally, the soluble silicon salt is selected from at least one of sodium silicate, sodium metasilicate and sodium fluorosilicate.

8. A method for preparing the crystal nucleus type early strengthening agent according to claim 6 or 7, characterized in that: The following operations are included: (a) taking a portion of the dispersant, diluting it with water and adjusting the pH to 12 to 14 to obtain a dispersant aqueous solution; (b) taking the remaining dispersant and mixing it with the silicate aqueous solution to obtain a dispersant-siliconate mixed aqueous solution; (c) under stirring conditions at 30 to 80° C., within 8 to 24 hours, the calcium salt aqueous solution and the dispersant-silicon salt mixed aqueous solution are simultaneously dripped into the dispersant aqueous solution, and cooled to room temperature.

9. The method according to claim 8, characterized in that The weight of the part of the dispersant in operation (a) accounts for 70% to 95% of the total weight of the dispersant; Optionally, in operation (a), an alkali solution is used to adjust the pH, wherein the alkali solution is a sodium hydroxide aqueous solution, and the mass fraction of the sodium hydroxide is 1 to 35%; Optionally, the mass fraction of the dispersant in the dispersant aqueous solution is 1-10%, the mass fraction of the soluble silicon salt in the silicon salt aqueous solution is 20-40%, and the mass fraction of the soluble calcium salt in the calcium salt aqueous solution is 40-70%.

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