Preparation method of high and easy strong dispersion water reducing agent

Abstract

The application provides a preparation method of a high-and-easy strong-dispersion water-reducing agent, which comprises the following steps: dissolving and uniformly stirring unsaturated polyether monomer A, prepolymer B and an oxidizing agent in deionized water to obtain a base material; dissolving and uniformly stirring a reducing agent and a chain transfer agent in deionized water to obtain solution 1; dissolving and uniformly stirring unsaturated acid monomer C, unsaturated amide monomer D and unsaturated silane monomer E in deionized water to obtain solution 2; adding solution 1 and 2 into the base material drop by drop, and keeping warm after the dropping is completed; cooling to room temperature, adding an alkaline compound to adjust the pH, and adding water to adjust the solid content, so as to obtain the high-and-easy strong-dispersion water-reducing agent. The water-reducing agent solves the problem of low conversion rate caused by low reactivity of maleic acid (anhydride) or fumaric acid, thereby solving the problem of storage stability of the water-reducing agent, and the obtained water-reducing agent has high and easy properties and strong dispersibility.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of concrete admixtures, and relates to a water reducing agent, in particular to a preparation method of a high-dispersion water reducing agent suitable for solid waste-based concrete. BACKGROUND

[0002] With the development of modern engineering technology, the long-distance transportation of concrete has become the norm in engineering construction. The long-distance transportation of concrete in the pump pipe puts forward higher and higher requirements for the rheological properties of the mixture. With the gradual depletion of natural sand, manufactured sand is widely used in the production of concrete. Due to the limitations of equipment and process, the manufactured sand often has a "two-thick, middle-thin" gradation. The lack of intermediate aggregate particles, which play a crucial role in the workability performance indicators of concrete such as wrapping and cohesion, makes the concrete prone to bleeding, running, and even segregation, increasing the risk of pump blockage during pumping and affecting the engineering quality.

[0003] On the other hand, with the rapid development of industry, a large amount of solid waste such as fly ash, carbide slag, desulfurization gypsum, steel slag, slag, and limestone powder is generated. These solid wastes have had adverse effects on the natural environment, land resources, and people's living environment. In the past decade, industrial solid waste has been extensively researched and applied in cementitious materials. To improve the activity of cementitious materials made from industrial solid waste in concrete, a combination of physical activation (grinding) and chemical activation (activator) is generally used. However, the fineness of the solid waste particles is greatly improved after grinding, and the use of chemical activators often results in high water demand, poor workability, and other issues in concrete. For example, fly ash with "ball bearing effect" composed of spherical particles can improve the fluidity and workability of concrete, but after grinding, the spherical particles are destroyed, leading to a decrease in fluidity and poor workability. For another example, the addition of desulfurization gypsum increases the competition for adsorption with polycarboxylate superplasticizer, reducing the dispersion effect of the superplasticizer. At the same time, due to the generally low early activity of solid waste-based concrete, it is easy to cause low early strength of concrete, affecting the progress of the project.

[0004] Therefore, in the face of the complex and diverse construction environment of modern engineering, as well as the application status of low-quality aggregates and multi-component cementitious materials in concrete, it is necessary to develop a polycarboxylate superplasticizer that can solve the problems of high water demand, poor workability, competition for adsorption, and early strength. Literature research shows that maleic acid (anhydride) and fumaric acid can effectively adjust the workability of concrete in the molecule of the superplasticizer. However, due to the low reactivity of maleic acid (anhydride) and fumaric acid, the conversion rate is low, making it difficult to achieve good dispersion effect. At the same time, maleic acid (anhydride) and fumaric acid that do not participate in the reaction are prone to precipitation, and the storage stability of the prepared superplasticizer is also poor. SUMMARY

[0005] The present application aims at the above-mentioned deficiencies in the prior art, and provides a high workability and strong dispersibility dispersing water-reducing agent, which solves the problem of low conversion rate caused by low reactivity of maleic acid (anhydride) or fumaric acid, thereby solving the problem of storage stability of the water-reducing agent, and making the obtained water-reducing agent have high workability and strong dispersibility.

[0006] The technical scheme adopted to achieve the above-mentioned objects of the present application is as follows:

[0007] A preparation method of a high workability and strong dispersibility dispersing water-reducing agent, comprising the following steps: (1) preparation of a base material: adding unsaturated polyether monomer A, prepolymer B and oxidizing agent into a reactor, dissolving and stirring uniformly with deionized water;

[0008] (2) preparation of solution ①: weighing a reducing agent and a chain transfer agent, dissolving and stirring uniformly with deionized water;

[0009] (3) preparation of solution ②: weighing unsaturated acid monomer C, unsaturated amide monomer D and unsaturated silane monomer E, dissolving and stirring uniformly with deionized water;

[0010] (4) synthesis reaction: simultaneously starting to drop solution ① and ② into the reactor with the base material, the dropping time is 0.5-4 hours, the reaction temperature is controlled to be 15-45℃, the total mass concentration of the reaction substances is controlled to be 40-60%, after the dropping of solution ① and ② is completed, the temperature is kept for 0.5-2 hours; cooling to room temperature, adding an alkaline compound to adjust the pH to 6.5-7.5, adding water to adjust the solid content to 40-50%, and the high workability and strong dispersibility dispersing water-reducing agent is obtained.

[0011] The mass ratio of monomer A to prepolymer B is 1:(0.1-2); the molar ratio of monomers A, C, D and E is 1:(2-5):(1-4):(0.5-2), the oxidizing agent accounts for 1-5% of the total number of moles of all reaction monomers, the reducing agent accounts for 0.1-3% of the total number of moles of all reaction monomers, and the chain transfer agent accounts for 0.5-3% of the total number of moles of all reaction monomers.

[0012] The preparation method of the prepolymer B is as follows: adding unsaturated polyether monomer F, unsaturated acid monomer G, oxidizing agent and deionized water into a reactor, stirring uniformly and heating to 30-60℃; dropping an aqueous solution of a reducing agent, the dropping time is 2-5 hours, after the dropping is completed, the temperature is kept for 1-2 hours, and then the temperature is cooled to room temperature, and water is added to adjust the solid content to 40-50%, and the prepolymer B is obtained: the molar ratio of the unsaturated acid monomer G to the unsaturated polyether monomer F is (1-3):1, the oxidizing agent accounts for 1-4% of the total number of moles of monomers F and G, and the reducing agent accounts for 0.1-4% of the total number of moles of monomers F and G.

[0013] The unsaturated polyether monomer F is iso-pentenyl alcohol polyoxyethylene ether, and the molecular weight is 2000-6000; the unsaturated acid monomer G is at least one of maleic acid (anhydride) or fumaric acid.

[0014] The oxidizing agent is at least one of peroxoacetic acid, hydrogen peroxide, benzoyl peroxide, potassium persulfate, ammonium persulfate, sodium persulfate; the reducing agent is at least one of sodium sulfite, sodium bisulfite, sodium metabisulfite, ferrous sulfate, ferrous pyrophosphate, sodium hypophosphite, L-ascorbic acid.

[0015] The unsaturated polyether monomer A is one or a mixture of two or more of methyl allyl polyoxyethylene ether, iso-pentenyl alcohol polyoxyethylene ether, ethylene glycol mono-vinyl polyoxyethylene ether.

[0016] The unsaturated acid C is at least one of acrylic acid, methacrylic acid.

[0017] The unsaturated amide monomer D is one or a mixture of two or more of acrylamide, N-vinyl caprolactam, N,N-dimethyl acrylamide, N,N-diethyl acrylamide, N-isopropyl acrylamide, N-vinyl pyrrolidone, N-vinyl acetamide, N-vinyl formamide or N-methyl-N-vinyl acetamide.

[0018] The unsaturated silane monomer E is one or a mixture of two or more of γ-methacryloyloxypropyl trimethoxysilane, methyl vinyl dimethoxysilane, methyl vinyl diethoxysilane, methyldiethoxysilane, vinyltrichlorosilane, vinylphenyldiethoxysilane, vinyl dimethoxymethyl silane, vinyl trimethoxysilane, vinyl triethoxysilane, allyl trimethoxysilane, allyl triethoxysilane or allyl trichlorosilane, vinyl tris(2-methoxyethoxy)silane.

[0019] The chain transfer agent is at least one of mercaptoacetic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, mercaptoethanol, mercaptopropanol, sodium methacrylate, dodecyl mercaptan, undecyl mercaptan, hexadecyl mercaptan, octadecyl mercaptan, sodium hypophosphite, isopropyl alcohol, trisodium phosphate, sodium formate, sodium acetate.

[0020] The basic compound is at least one of ammonia, alkali hydroxide.

[0021] Compared with the prior art, the high workability and strong dispersion type water reducing agent provided by the application has the following advantages: 1. The application starts from the molecular structure design theory, uses maleic acid (anhydride) or fumaric acid and the reactant of unsaturated polyether as a prepolymer to participate in the secondary polymerization reaction of a high reactivity system, so that the maleic acid (anhydride) and the fumaric acid are ensured to fully participate in the reaction, the problem of low conversion rate caused by low reactivity is solved, the problem of storage stability of the water reducing agent is solved, and the water reducing agent is successfully introduced into the polycarboxylic acid water reducing agent system to play a workability adjusting role.

[0022] 2. In the application, the unsaturated monomer with a silane group and an amide group is reacted with unsaturated acid and unsaturated polyether, the silane group can be hydrolyzed to occur condensation with the hydroxyl group on the surface of the cementitious material particles to produce chemical adsorption, the adsorption competitiveness of the polycarboxylic acid water reducing agent in a complex cementitious material system is enhanced, and the dispersion effect is ensured; the amide group can provide good workability and early strength function. DETAILED DESCRIPTION

[0023] The following implementation cases more specifically describe the preparation process of the high workability and strong dispersion type water reducing agent of the application, and the implementation cases are given in an illustrative manner, so that those skilled in the art of the project can understand the content of the application and implement it, but the implementation cases do not limit the protection scope of the application at all. Any equivalent changes or modifications made according to the spirit and essence of the application should be covered within the protection scope of the application.

[0024] Example 1

[0025] The high workability and strong dispersion type water reducing agent provided in the embodiment is prepared by the following method:

[0026] (1) Preparation of the prepolymer: in a four-necked flask equipped with a stirrer, a thermometer, a constant flow pump and a condenser reflux tube, 300 g (0.125 mol) of isoamyl alcohol polyoxyethylene ether with a molecular weight of 2400, 24.5 g (0.25 mol) of maleic anhydride, 300 g of deionized water and 1.39 g (0.01125 mol) of 27.5% concentration hydrogen peroxide are added, stirred uniformly and heated to 60℃. A solution composed of 0.33 g (0.001875 mol) of L-ascorbic acid and 30 g of deionized water is added dropwise, the dropwise adding time is 3 h, after the dropwise adding is completed, the solution is preserved for 1 h, 65 g of deionized water is added to adjust the solid content to 45%, and then the solution is cooled to room temperature to obtain the prepolymer.

[0027] (2) Base material preparation: In a four-necked flask equipped with a stirrer, a thermometer, and a constant flow pump, 300 g (0.1 mol) of ethylene glycol monovinyl polyoxyethylene ether with a molecular weight of 3000, 100 g of the prepolymer, 1.61 g (0.00706 mol) of ammonium persulfate, and 244 g of deionized water were added, stirred uniformly, and controlled at a temperature of 15°C.

[0028] (3) Solution ① preparation: 0.2714 g (0.0023 mol) of sodium alginate and 1.166 g (0.011 mol) of 3-mercaptopropionic acid were weighed, dissolved in 20 g of deionized water, and stirred uniformly.

[0029] (4) Solution ② preparation: 14.4 g (0.2 mol) of acrylic acid, 7.1 g (0.1 mol) of acrylamide, 12.4 g (0.05 mol) of γ-methacryloyloxypropyltrimethoxysilane, and 20 g of deionized water were weighed, dissolved, and stirred uniformly.

[0030] (5) Synthesis reaction: Solution ① and ② were simultaneously started to be added dropwise to the four-necked flask with the base material. The dropwise addition time of solution ① was 70 min, and that of solution ② was 60 min. After the dropwise addition was completed, the solution was incubated for 1 h, cooled to room temperature, adjusted to a pH of 7.0 by adding NaOH, and adjusted to a solid content of 50% by adding 50 g of deionized water, thereby obtaining the high-and-workability strong dispersing type water reducing agent PCE-1.

[0031] Example 2

[0032] The high-and-workability strong dispersing type water reducing agent provided in this example was prepared by the following method:

[0033] (1) Preparation of the prepolymer: In a four-necked flask equipped with a stirrer, a thermometer, a constant flow pump, and a condenser reflux tube, 280 g (0.1 mol) of isoamylene polyoxyethylene ether with a molecular weight of 2800, 34.8 g (0.3 mol) of fumaric acid, 245 g of deionized water, and 2.7 g (0.01 mol) of potassium persulfate were added, stirred uniformly, and heated to 45°C. A solution composed of 0.416 g (0.004 mol) of sodium bisulfite and 30 g of deionized water was added dropwise, the dropwise addition time was 3.5 h, and after the dropwise addition was completed, the solution was incubated for 1 h, 37 g of deionized water was added, the solid content was adjusted to 50%, and the solution was cooled to room temperature, thereby obtaining the prepolymer.

[0034] (2) Base material preparation: In a four-necked flask equipped with a stirrer, a thermometer, and a constant flow pump, 300 g (0.125 mol) of methyl allyl polyoxyethylene ether with a molecular weight of 2400, 120 g of the prepolymer, 3.50 g (0.046 mol) of peroxyacetic acid, and 234 g of deionized water were added, stirred uniformly, and controlled at a temperature of 25°C.

[0035] (3) Solution ① preparation: weigh ferrous sulfate 1.368 g (0.009 mol) and mercaptoacetic acid 1.932 g (0.021 mol), add 20 g of deionized water to dissolve and stir uniformly.

[0036] (4) Solution ② preparation: weigh methacrylic acid 37.625 g (0.4375 mol), N, N-dimethyl acrylamide 24.75 g (0.25 mol), methyl vinyl dimethoxy silane 13.2 g (0.1 mol) and deionized water 46 g, dissolve and stir uniformly.

[0037] (5) Synthesis reaction: start dropping solution ① and ② into the four-necked flask with the bottom material at the same time. The dropping time of solution ① is 140 min, and the dropping time of solution ② is 120 min. After the dropping is completed, keep warm for 1.5 h, cool to room temperature, add ammonia water to adjust the pH to 7.0, add 75 g of deionized water, and adjust the solid content of the solution to 50%, to obtain the high and easy strong dispersible water reducer PCE-2.

[0038] Example 3

[0039] The high and easy strong dispersible water reducer provided in this example is prepared by the following method:

[0040] (1) Preparation of prepolymer: in a four-necked flask equipped with a stirrer, a thermometer, a constant flow pump and a condenser reflux tube, add isopentenyl alcohol polyoxyethylene ether with a molecular weight of 4000 320 g (0.08 mol), maleic acid 18.56 g (0.16 mol), deionized water 280 g, sodium persulfate 1.666 g (0.007 mol), stir uniformly and heat to 55°C. Add a solution composed of sodium hypophosphite 0.4224 g (0.0048 mol) and deionized water 30 g, the dropping time is 4 h, keep warm for 1 h after the dropping is completed, add 24 g of deionized water, and adjust the solid content to 50%, and cool to room temperature to obtain the prepolymer.

[0041] (2) Preparation of bottom material: in a four-necked flask equipped with a stirrer, a thermometer and a constant flow pump, add isopentenyl alcohol polyoxyethylene ether with a molecular weight of 4000 280 g (0.07 mol), prepolymer 240 g, benzoyl peroxide 6.788 g (0.028 mol), deionized water 230 g, stir uniformly, and control the temperature to be 45°C.

[0042] (3) Solution ① preparation: weigh ferrous pyrophosphate 1.596 g (0.0056 mol) and sodium methacrylsulfonate 2.0382 g (0.0129 mol), add 35 g of deionized water to dissolve and stir uniformly.

[0043] (4) Solution ② preparation: weigh methacrylic acid 21.07 g (0.245 mol), N-vinyl acetamide 11.9 g (0.14 mol), vinyl trimethoxysilane 8.288 g (0.056 mol) and deionized water 50 g, dissolve and stir uniformly.

[0044] (5) Synthesis reaction: simultaneously start dropping solution ① and ② into the four-necked flask with the bottom material. The dropping time of solution ① is 210 min, and the dropping time of solution ② is 180 min. After the dropping is completed, keep warm for 1 h, cool to room temperature, add potassium hydroxide to adjust the pH to 7.0, add deionized water 35 g, and adjust the solid content of the solution to 45% to obtain a high and easy strong dispersible water reducer PCE-3.

[0045] Example 4

[0046] The high and easy strong dispersible water reducer provided in this example is prepared by the following method:

[0047] (1) Preparation of the prepolymer: in a four-necked flask equipped with a stirrer, a thermometer, a constant flow pump and a condenser reflux tube, isopentenyl alcohol polyoxyethylene ether with a molecular weight of 2400 300 g (0.125 mol), fumaric acid 14.5 g (0.125 mol), deionized water 258 g, benzoyl peroxide 1.21 g (0.005 mol) are added, stirred uniformly and heated to 60°C. A solution composed of ferrous sulfate 0.57 g (0.00375 mol) and deionized water 30 g is dropped, the dropping time is 2.5 h, after the dropping is completed, keep warm for 2 h, add deionized water 22 g, adjust the solid content to 50%, and cool to room temperature to obtain the prepolymer.

[0048] (2) Preparation of the bottom material: in a four-necked flask equipped with a stirrer, a thermometer and a constant flow pump, ethylene glycol monovinyl polyoxyethylene ether with a molecular weight of 4300 172 g (0.04 mol), the prepolymer 320 g, ammonium persulfate 0.912 g (0.004 mol), deionized water 190 g are added, stirred uniformly, and the temperature is controlled at 20°C.

[0049] (3) Preparation of solution ①: weigh L-ascorbic acid 0.352 (0.002 mol) and dodecyl mercaptan 1.616 g (0.008 mol), add deionized water 35 g to dissolve and stir uniformly.

[0050] (4) Preparation of solution ②: weigh acrylic acid 6.336 g (0.088 mol), N-isopropyl acrylamide 5.424 g (0.048 mol), allyl trimethoxysilane 6.48 g (0.04 mol) and deionized water 50 g, dissolve and stir uniformly.

[0051] (5) Synthesis reaction: simultaneously start dropping solution ① and ② into the four-necked flask with the bottom material. The dropping time of solution ① is 60 min, and that of solution ② is 50 min. After the dropping is completed, keep warm for 30 min, cool to room temperature, add NaOH to adjust the pH to 7.0, add 88 g of deionized water, and adjust the solid content of the solution to 40% to obtain the high and easy dispersion type water reducing agent PCE-4.

[0052] Comparative Example 1

[0053] The substances used in this comparative example are all the same as in Example 1. In this comparative example, no pre-polymerization is performed, but a direct polymerization method is used to synthesize the water reducing agent. The specific preparation method is as follows:

[0054] (1) Preparation of the bottom material: in a reaction kettle equipped with a stirrer, a thermometer, and a constant flow pump, add isopentenyl alcohol polyoxyethylene ether with a molecular weight of 3000 300 g (0.1 mol), maleic anhydride 3.78 g (0.0385 mol) which is equivalent to the amount used in the pre-polymer in Example 1, ammonium persulfate 1.61 g (0.00706 mol), and deionized water 244 g, stir uniformly, and control the temperature at 15°C.

[0055] (2) Preparation of solution ①: weigh thymol 0.277 g (0.0023 mol) and 3-mercaptopropionic acid 1.166 g (0.011 mol), dissolve in 20 g of deionized water and stir uniformly.

[0056] (3) Preparation of solution ②: weigh acrylic acid 14.4 g (0.2 mol), acrylamide 7.1 g (0.1 mol), γ-methacryloyloxypropyltrimethoxysilane 12.4 g (0.05 mol), and deionized water 20 g, dissolve and stir uniformly.

[0057] (5) Synthesis reaction: simultaneously start dropping solution ① and ② into the four-necked flask with the bottom material. The dropping time of solution ① is 60 min, and that of solution ② is 50 min. After the dropping is completed, keep warm for 30 min, cool to room temperature, add NaOH to adjust the pH to 7.0, add 88 g of deionized water, and adjust the solid content of the solution to 40% to obtain the high and easy dispersion type water reducing agent PCE-4.

[0058] Comparative Example 2

[0059] The preparation method of the water reducing agent in this comparative example is basically the same as in Comparative Example 1, except that the amount of maleic anhydride is increased in this comparative example. The specific preparation method is as follows:

[0060] (1) Base material preparation: In a reaction kettle equipped with a stirrer, a thermometer and a constant flow pump, 300 g (0.1 mol) of isopentenyl alcohol polyoxyethylene ether with a molecular weight of 3000, 9.8 g (0.1 mol) of maleic anhydride, 1.61 g (0.00706 mol) of ammonium persulfate and 244 g of deionized water were added, stirred uniformly, and the temperature was controlled at 15°C.

[0061] (2) Preparation of solution ①: 0.277 g (0.0023 mol) of sodium sulfite and 1.166 g (0.011 mol) of 3-mercaptopropionic acid were weighed, dissolved in 20 g of deionized water and stirred uniformly.

[0062] (3) Preparation of solution ②: 14.4 g (0.2 mol) of acrylic acid, 7.1 g (0.1 mol) of acrylamide, 12.4 g (0.05 mol) of γ-methacryloyloxypropyltrimethoxysilane and 20 g of deionized water were weighed, dissolved and stirred uniformly.

[0063] (5) Synthesis reaction: Solution ① and ② were simultaneously started to be added dropwise into the four-necked flask with the base material. The dropwise addition time of solution ① was 70 min, and the dropwise addition time of solution ② was 60 min. After the dropwise addition was completed, the solution was incubated for 1 h, cooled to room temperature, NaOH was added to adjust the pH to 7.0, 50 g of deionized water was added, and the solid content of the solution was adjusted to 50%, to obtain the water reducing agent PCE-B.

[0064] The water reducing agents prepared in Examples 1-4 and Comparative Examples 1-2 were subjected to molecular weight testing. The number average molecular weight of the water reducing agent in the present application was tested by a Viscotek TDA305max multi-detector gel permeation chromatograph produced by Malvern, UK, the mobile phase was 0.1 mol / L sodium nitrate solution, the flow rate was 0.7 mL / min, and the chromatographic column was A-Guard+1 x A6000M. The test results are shown in the following table.

[0065]

[0066] As can be seen from the above table, compared with PCE-A and PCE-B which are not subjected to secondary polymerization with a high-activity reaction system, the conversion rate of the water reducing agent prepared in the present application is significantly improved. Moreover, the water reducing agents prepared in Examples 1-4 have excellent storage performance and can be stored for a long time at room temperature.

[0067] Application example

[0068] The water reducing agent was applied to C30 and C60 solid waste-based concrete. The components of the C30 and C60 solid waste-based concrete were as follows:

[0069]

[0070] The cement in the formula is YADONG P·O42.5, the main components of the solid waste-based cementitious material are fly ash, slag, stone powder and gypsum, the specific surface area is 693 m 2 / kg, the fineness modulus of the machine-made sand is 3.3, the fineness modulus of the river sand is 2.6, the broken stone is 5-25 mm continuous gradation broken stone, and the water is tap water.

[0071] The water reducing agents prepared in the above examples 1-4 and comparative examples 1-2 are applied to the C30 and C60 solid waste-based concrete in the above table, and the performance of the concrete is tested, the performance test of the concrete in the application is carried out according to GB8076-2008 "Concrete Admixture", and the dosage of the water reducing agent is the dosage when the water reducing agent is diluted to 10% concentration. The test results are shown in the following table.

[0072]

[0073] As can be seen from the data in the above table, when the water reducing agents prepared in examples 1-4 are applied to the concrete, they have better initial dispersing performance.

Claims

1. A method for preparing a highly workable and strongly dispersible water-reducing agent, characterized in that... Includes the following steps: (1) Preparation of base material: Add unsaturated polyether monomer A, prepolymer B and oxidant to the reactor, add deionized water to dissolve and stir evenly; The preparation method of the prepolymer B is as follows: unsaturated polyether monomer F, unsaturated acid monomer G, oxidant and deionized water are added to a reactor, stirred evenly and heated to 30~60℃; an aqueous solution of reducing agent is added dropwise over 2~5 hours, and after the addition is completed, the temperature is maintained for 1~2 hours, cooled to room temperature, and water is added to adjust the solid content to 40~50%, thus obtaining prepolymer B: the molar ratio of unsaturated acid monomer G to unsaturated polyether monomer F is (1~3):1, the oxidant accounts for 1~4% of the total molar amount of monomers F and G, and the reducing agent accounts for 0.1~4% of the total molar amount of monomers F and G; the unsaturated acid monomer G is at least one of maleic acid (anhydride) or fumaric acid; (2) Solution ① Preparation: Weigh the reducing agent and chain transfer agent, add deionized water to dissolve and stir evenly; (3) Solution ② preparation: Weigh unsaturated acid monomer C, unsaturated amide monomer D and unsaturated silane monomer E, add deionized water to dissolve and stir evenly; (4) Synthesis reaction: Simultaneously, solutions ① and ② are added dropwise to the reactor containing the substrate. The dropwise addition time is 0.5 to 4 hours. The reaction temperature is controlled at 15 to 45°C. The total mass concentration of each reactant is controlled at 40 to 60%. After the addition of solutions ① and ② is completed, the temperature is maintained for 0.5 to 2 hours. After cooling to room temperature, an alkaline compound is added to adjust the pH to 6.5 to 7.

5. Water is added to adjust the solid content to 40 to 50%, thus obtaining a highly workable and dispersible water-reducing agent.

2. The preparation method of the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The mass ratio of monomer A to prepolymer B is 1:(0.1~2); the molar ratio of monomers A, C, D, and E is 1:(2~5):(1~4):(0.5~2); the oxidant accounts for 1~5% of the total molar amount of all reactive monomers; the reducing agent accounts for 0.1~3% of the total molar amount of all reactive monomers; and the chain transfer agent accounts for 0.5~3% of the total molar amount of all reactive monomers.

3. The preparation method of the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The unsaturated polyether monomer F is isopentenyl alcohol polyoxyethylene ether with a molecular weight of 2000~6000.

4. The preparation method of the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The oxidizing agent is at least one of peracetic acid, hydrogen peroxide, benzoyl peroxide, potassium persulfate, ammonium persulfate, and sodium persulfate; the reducing agent is at least one of sodium formaldehyde sulfoxylate, sodium bisulfite, sodium metabisulfite, ferrous sulfate, ferrous pyrophosphate, sodium hypophosphite, and L-ascorbic acid.

5. The preparation method of the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The unsaturated polyether monomer A is one or a mixture of two or more of methyl allyl polyoxyethylene ether, isopentenyl polyoxyethylene ether, and ethylene glycol monovinyl polyoxyethylene ether.

6. The preparation method of the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The unsaturated acid C is at least one of acrylic acid and methacrylic acid.

7. The preparation method of the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The unsaturated amide monomer D is one or a mixture of two or more of acrylamide, N-vinylcaprolactam, N,N-dimethylacrylamide, N,N-diethylacrylamide, N-isopropylacrylamide, N-vinylpyrrolidone, N-vinylacetamide, N-vinylformamide or N-methyl-N-vinylacetamide.

8. The preparation method of the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The unsaturated silane monomer E is one or a mixture of two or more of γ-methacryloyloxypropyltrimethoxysilane, methyl vinyldimethoxysilane, methyl vinyldiethoxysilane, vinyltrichlorosilane, vinylphenyldiethoxysilane, vinyldimethoxymethylsilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, or allyltrichlorosilane and vinyltri(2-methoxyethoxy)silane.

9. The method for preparing the highly workable and strongly dispersible water-reducing agent according to claim 1, characterized in that: The chain transfer agent is at least one of mercaptoacetic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, mercaptoethanol, mercaptopropanol, sodium methacrylate sulfonate, dodecyl mercaptan, undecyl mercaptan, hexadecyl mercaptan, octadecyl mercaptan, sodium hypophosphite, isopropanol, trisodium phosphate, sodium formate, and sodium acetate; the alkaline compound is at least one of ammonia and alkali metal hydroxide.

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