A mud-inhibiting polycarboxylate superplasticizer and its preparation method

Abstract

This invention relates to a mud-inhibiting polycarboxylate superplasticizer and its preparation method. The raw materials for preparing the mud-inhibiting polycarboxylate superplasticizer, by weight, include: 90-260 parts of allyl-terminated polyether monomer; 20-32 parts of unsaturated acid monomer; 8-15 parts of unsaturated ester monomer; 4-8 parts of quaternary ammonium salt compound; 1.5-3.0 parts of oxidant; 0.2-0.4 parts of reducing agent; 0.8-1.5 parts of chain transfer agent; and water. The allyl-terminated polyether monomer comprises unsaturated alcohol, allyl compound, and alkaline catalyst. The polycarboxylate superplasticizer prepared by the method of this invention has advantages such as low dosage, high water reduction, good workability, low dosage sensitivity, and excellent mud inhibition, significantly improving the dispersion and adsorption performance of concrete and having a wide adaptability range for the mud content of sand and gravel.

Description

Technical Field

[0001] This invention relates to the field of concrete admixtures, specifically to a mud-inhibiting polycarboxylate superplasticizer and its preparation method. Background Technology

[0002] Concrete admixtures are currently the most widely researched and applied type of concrete additives. They can effectively reduce cement usage, water consumption, and increase concrete strength while maintaining the workability of concrete. Among them, polycarboxylate superplasticizers are widely used in various construction projects due to their advantages such as low dosage, good slump retention, highly controllable molecular structure, and green and environmentally friendly production process.

[0003] However, with the rapid development of the construction industry, the consumption of cement and sand in engineering construction has been continuously increasing, leading to a growing shortage of sand and gravel resources. The scarcity of natural sand and gravel resources is gradually becoming apparent nationwide. This resource shortage directly results in significant fluctuations in the quality of sand and gravel materials, particularly the frequent occurrence of high and unstable mud content. Due to differences in raw materials and the influence of environmental conditions, the problem of insufficient fluidity or excessively rapid loss of fluidity in freshly mixed concrete often occurs, potentially causing segregation and bleeding, thus increasing the difficulty of controlling concrete production. The root cause of these problems lies in the insufficient compatibility between admixtures and concrete raw materials.

[0004] In concrete with high clay or slurry content, the dispersibility of admixtures decreases significantly, leading to reduced concrete fluidity and strength. Furthermore, existing water-reducing agents exhibit poor performance stability under varying temperature and humidity conditions, and their adaptability to different brands and types of cement, fine aggregates, and coarse aggregates is limited.

[0005] To address these issues, common methods include compounding mud inhibitors, water-retaining agents, or other performance-improving additives. While these methods alleviate the problem of large slump loss in concrete to some extent, they also bring challenges such as increased costs, prolonged setting time, and reduced strength. Another approach is to use mud-inhibiting water-reducing agents. These agents, through optimized molecular structure and formulation design, exhibit good dispersibility in concrete with high clay or mud content, while also possessing excellent environmental adaptability and broad compatibility with various raw materials.

[0006] Therefore, developing a low-sensitivity mud-inhibiting polycarboxylate superplasticizer and its preparation method to meet the demand for high-performance admixtures in modern concrete engineering is of great practical significance and technical value. Summary of the Invention

[0007] Therefore, it is necessary to provide a mud-inhibiting polycarboxylate superplasticizer to effectively solve the problem that the dispersion performance of admixtures will significantly decrease in concrete with high clay or mud content.

[0008] To achieve the above objectives, the present invention provides a technical solution:

[0009] A mud-inhibiting polycarboxylate superplasticizer, wherein the raw materials for preparing the mud-inhibiting polycarboxylate superplasticizer, by weight, include:

[0010]

[0011] The raw materials for preparing the allyl-terminated polyether monomer include unsaturated alcohols, allyl compounds, and alkaline catalysts.

[0012] Specifically, the reducing agent includes at least one of ascorbic acid, sodium formaldehyde sulfoxylate, sodium sulfite, sodium formaldehyde sulfoxylate, sodium bisulfite, and sodium hypophosphite, wherein sodium hypophosphite can also act as a chain transfer agent;

[0013] Oxidizing agents include at least one of hydrogen peroxide, sodium peroxide, potassium peroxide, magnesium peroxide, sodium persulfate, ammonium persulfate, sodium dichromate, potassium dichromate, and potassium permanganate;

[0014] Chain transfer agents include at least one of thioglycolic acid, sodium hypophosphite, trisodium phosphate, mercaptopropionic acid, mercaptoethanol, and mercaptoacetic acid;

[0015] Unsaturated acid monomers include at least one of acrylic acid, methacrylic acid, fumaric acid, maleic anhydride, and itaconic acid;

[0016] The unsaturated ester monomers include at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and acetic acid.

[0017] Furthermore, the allyl-terminated polyether monomer has the following structural formula:

[0018]

[0019] Wherein, R1 is CH3-, CH3CH2-, or (CH3)2CH-;

[0020] R2 is CH3-, CH3CH2-, or (CH3)2CH-;

[0021] R3 is CH3-, CH3CH2-, or (CH3)2CH-.

[0022] Furthermore, the allyl compound includes at least one of allyl chloride and allyl bromide.

[0023] Furthermore, the alkaline catalyst includes at least one of potassium hydroxide, sodium hydroxide, and triethanolamine.

[0024] Furthermore, the raw materials for preparing the allyl-terminated polyether monomer also include phosphoric acid, and the weight ratio of unsaturated alcohol, allyl chloride compound, alkaline catalyst and phosphoric acid is (18-20):(4-8):(8-12):(0.3-0.6).

[0025] Furthermore, the structural formula of the quaternary ammonium salt compound is as follows:

[0026]

[0027]

[0028] One of them.

[0029] Furthermore, the raw materials for preparing the mud-inhibiting polycarboxylate superplasticizer, in parts by weight, include:

[0030] Ferrous sulfate 0.01-0.02 parts.

[0031] This invention also provides a method for preparing a mud-inhibiting polycarboxylate superplasticizer, comprising the following steps:

[0032] S100. Stir the allyl-terminated polyether monomer, oxidant and water until they are completely dissolved to obtain the base liquid;

[0033] S200. Add solution A and solution B dropwise to the base liquid. After the addition is complete, continue to keep the reaction at the temperature for 1 to 2 hours to obtain the mud-blocking polycarboxylate superplasticizer.

[0034] Wherein, solution A is an aqueous solution of unsaturated acid monomers, unsaturated ester monomers and quaternary ammonium salt compounds;

[0035] Solution B is an aqueous solution of a reducing agent and a chain transfer agent.

[0036] In some embodiments, ferrous sulfate is added during the preparation of the mud-inhibiting polycarboxylate superplasticizer, and the specific steps are as follows:

[0037] S100. Stir allyl-terminated polyether monomer, oxidant, ferrous sulfate and water until completely dissolved to obtain the base solution;

[0038] S200. Add solution A and solution B dropwise to the base liquid. After the addition is complete, continue to keep the reaction at the temperature for 1 to 2 hours to obtain the mud-blocking polycarboxylate superplasticizer.

[0039] Wherein, solution A is an aqueous solution of unsaturated acid monomers, unsaturated ester monomers and quaternary ammonium salt compounds;

[0040] Furthermore, the preparation method of the allyl-terminated polyether monomer includes the following steps:

[0041] A basic catalyst was added to the unsaturated alcohol to obtain the first mixture;

[0042] The allyl compound was added dropwise to the first mixture while maintaining the temperature in a water bath at 55℃~65℃. The mixture was stirred at a constant temperature for 4h~6h. After the addition was complete, the reaction was continued at the temperature for 1h~2h to obtain the allyl-terminated polyether monomer.

[0043] Furthermore, the method for preparing the quaternary ammonium salt compound monomer includes the following steps:

[0044] Dopamine is dissolved in an acidic solution to obtain a dopamine solution;

[0045] Aldehydes are dissolved in alcohol solutions to obtain aldehyde compound solutions;

[0046] An aldehyde compound solution was added to the dopamine solution, and the mixture was stirred for 18-24 hours. The pH was then adjusted to neutral to obtain compound A.

[0047] Compound A is dissolved in an alcohol solution in a water bath at 55°C–65°C. An alkali is added, and the reaction is allowed to proceed for 3–5 hours. Then, a 3-chloro-2-hydroxypropyltrimethylammonium chloride solution is added dropwise, and the reaction continues for another 4–5 hours to obtain the quaternary ammonium salt compound. More specifically, the quaternary ammonium salt compound can be washed with a washing solvent, including at least one of acetone, ethanol, and water; the alcohol solution includes at least one of methanol, ethanol, isopropanol, n-butanol, and ethylene glycol.

[0048] The weight ratio of dopamine, aldehydes, and acidic solution is 1:(0.75-1.25):(50-62.5); specifically, the aldehydes include at least one of salicylaldehyde, o-vanillin, benzaldehyde, 4-bromo-2-hydroxybenzaldehyde, and 2-hydroxy-1-naphthaldehyde.

[0049] Acidic solutions include at least one of acetic acid, propionic acid, formic acid, and dilute hydrochloric acid.

[0050] The beneficial effects of this invention are:

[0051] The present invention has the following advantages:

[0052] 1. This invention introduces allyl-terminated polyether monomers into the mud-blocking polycarboxylate superplasticizer, thereby introducing some short side chain structures into the molecular structure of the mud-blocking polycarboxylate superplasticizer. This enhances its steric hindrance effect while reducing the branch density, resulting in a polymer with a more uniform distribution of side chains. This gives the mud-blocking polycarboxylate superplasticizer better water-reducing performance and excellent low-sensitivity properties.

[0053] In addition, allyl-terminated polyether monomers can improve the water-reducing agent's resistance to slurry, and maintain good dispersion performance even in concrete containing high clay or slurry content, thereby improving the fluidity and strength of the concrete.

[0054] Enhanced stability: Allyl-terminated polyether monomers can improve the stability of water-reducing agents under different environmental conditions and reduce the impact of external factors on the performance of water-reducing agents.

[0055] 2. This invention introduces quaternary ammonium salt compounds into the mud-inhibiting polycarboxylate superplasticizer, which increases the steric hindrance effect of the molecules, more effectively disperses cement particles, and improves the fluidity and workability of concrete. It also enhances the adsorption capacity of the superplasticizer on the surface of cement particles, forming a more stable adsorption layer. This is beneficial for its wetting and adsorption of cement, improving the dispersibility and fluidity of concrete.

[0056] 3. In the preparation method of the present invention, unsaturated ester monomers, unsaturated carboxylic acid monomers, reducing agents and water are copolymerized to introduce carboxylate groups and ester groups into the polymer molecular structure.

[0057] The block polyether macromonomers in the side chains of the water-reducing agent are connected to the main chain of the water-reducing agent through oxygen, which reduces the spatial resistance of the side chain swing and increases the degree of freedom of movement of the polyether macromonomers in the side chains. This improves the encapsulation and entanglement of the polyether macromonomers in the side chains of the water-reducing agent, thus giving it a strong adsorption capacity. At the same time, the ester groups are continuously hydrolyzed during the cement hydration process and continue to react with the cement hydration products, inhibiting the growth of Ca(OH)2 and AFt crystal nuclei, slowing down the hydration rate, and prolonging the cement hydration induction period, thereby improving the dispersion retention.

[0058] 4. The mud-inhibiting polycarboxylate superplasticizer prepared by the method of the present invention has the advantages of low dosage, high water reduction, good workability, low dosage sensitivity and excellent mud inhibition, can significantly improve the dispersion and adsorption performance of concrete, and has a wide range of adaptability to mud content in sand and gravel. Detailed Implementation

[0059] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0060] In the embodiments, unless otherwise specified, the experimental methods used are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0061] I. Preparation of allyl-terminated polyether monomer A

[0062] 1. Allyl-terminated polyether monomer A1:

[0063] 200 parts of 3,7-dimethyl-6-octen-1-ol were added to a four-necked flask, along with 60 parts of potassium hydroxide. The mixture was kept at 55°C in a water bath under a nitrogen atmosphere. Then, 100 parts of allyl chloride compound were slowly added dropwise, and the mixture was stirred at this temperature for 4 hours. After the addition was complete, the mixture was kept at the same temperature for another 2 hours. Finally, 5 parts of phosphoric acid were added for neutralization, followed by purification to obtain the allyl-terminated polyether monomer A1.

[0064] 2. Allyl-terminated polyether monomer A2:

[0065] 200 parts of hydroxycitronellol were added to a four-necked flask, along with 60 parts of potassium hydroxide. The mixture was then kept at 55°C in a water bath under a nitrogen atmosphere. Subsequently, 100 parts of allyl chloride compound were slowly added dropwise, and the mixture was stirred at this temperature for 4 hours. After the addition was complete, the mixture was kept at the same temperature for another 2 hours. Finally, 5 parts of phosphoric acid were added for neutralization, followed by purification to obtain the allyl-terminated polyether monomer A2.

[0066] II. Preparation of Quaternary Ammonium Compound B

[0067] 1. Preparation of quaternary ammonium salt compound B1:

[0068] 1.6 g of dopamine was dissolved in 80 mL of acetic acid, and then 1.2 g of salicylaldehyde was dissolved in 100 mL of anhydrous methanol and added to the dopamine solution. The mixture was stirred for 18 hours. The pH was adjusted to 7 using sodium hydroxide solution, followed by washing with a suitable cleaning solvent and vacuum drying to obtain compound A.

[0069] 1.6 g of compound A was dissolved in 100 mL of isopropanol, and 10 mL of 40% sodium hydroxide was added. The mixture was reacted in a water bath at 55 °C for 4 h. Subsequently, under the same water bath conditions, 30 mL of an aqueous solution of 3-chloro-2-hydroxypropyltrimethylammonium chloride (40 wt.%) was slowly added dropwise, and the temperature was controlled at 60 °C, and the reaction was continued for 4-5 h. Finally, the obtained product was washed with an alcohol solution and dried under vacuum to obtain the quaternary ammonium salt compound B1.

[0070] 2. Preparation of quaternary ammonium salt compound B2:

[0071] 1.6 g of dopamine was dissolved in 80 mL of acetic acid. Then, 2.0 g of 4-bromo-2-hydroxybenzaldehyde was dissolved in 100 mL of anhydrous methanol and added to the dopamine solution. The mixture was stirred for 24 hours. The pH was adjusted to neutral using sodium hydroxide solution, followed by washing with a suitable cleaning solvent and vacuum drying to obtain compound A.

[0072] 1.6 g of compound A was dissolved in 100 mL of isopropanol, and 10 mL of 40% sodium hydroxide was added. The mixture was reacted in a water bath at 55 °C for 4 h. Subsequently, under the same water bath conditions, 30 mL of an aqueous solution of 3-chloro-2-hydroxypropyltrimethylammonium chloride (40 wt.%) was slowly added dropwise, and the temperature was controlled at 60 °C for another 4 h. Finally, the product was washed with an alcohol solution and dried under vacuum to obtain the quaternary ammonium salt compound B2.

[0073] 3. Preparation of quaternary ammonium salt compound B3:

[0074] 1.6 g of dopamine was dissolved in 80 mL of acetic acid. Then, 1.5 g of o-vanillin was dissolved in 100 mL of anhydrous methanol and added to the dopamine solution. The mixture was stirred for 20 hours. The pH was adjusted to neutral using sodium hydroxide solution, followed by washing with a suitable cleaning solvent and vacuum drying to obtain compound A.

[0075] Next, 1.6 g of compound A was dissolved in 100 mL of isopropanol, and 10 mL of 40% sodium hydroxide was added. The mixture was reacted in a water bath at 55 °C for 4 h. Subsequently, under the same water bath conditions, 30 mL of an aqueous solution of 3-chloro-2-hydroxypropyltrimethylammonium chloride (40 wt.%) was slowly added dropwise, and the temperature was controlled at 60 °C, and the reaction was continued for 5 h. Finally, the obtained product was washed with an alcohol solution and dried under vacuum to obtain the quaternary ammonium salt compound B3.

[0076] III. Preparation of Sludge-Inhibiting Polycarboxylate Superplasticizer

[0077] Example 1

[0078] Place 180g of allyl-terminated polyether monomer A1 and 300g of water in a four-necked flask, stir to dissolve, then add 0.01g of ferrous sulfate and 1.5g of hydrogen peroxide to obtain the bottom solution;

[0079] Adjust the reaction temperature to 20℃, and simultaneously add solution A and solution B to the bottom liquid in the four-necked flask. After the addition is complete, keep the temperature for 1 hour, and then add liquid alkali to neutralize, thus preparing the mud-inhibiting polycarboxylate superplasticizer.

[0080] Solution A is a solution prepared from 22g acrylic acid, 8g hydroxyethyl acrylate, 4g quaternary ammonium salt compound B1 and 10g water. The dropping time of solution A is 60min.

[0081] Solution B is a solution prepared from 0.2g ascorbic acid, 0.22g mercaptoethanol and 42g water. The dropping time of solution B is 60min.

[0082] Example 2

[0083] Place 180g of allyl-terminated polyether monomer A2 and 300g of water in a four-necked flask, stir to dissolve, then add 0.01g of ferrous sulfate and 1.5g of hydrogen peroxide to obtain the bottom solution;

[0084] Adjust the reaction temperature to 35℃, and simultaneously add solution A and solution B to the bottom liquid in the four-necked flask. After the addition is complete, keep the temperature for 1-2 hours, and then add liquid alkali to neutralize and prepare the mud-blocking polycarboxylate superplasticizer.

[0085] Solution A is a solution prepared from 22g methacrylic acid, 8g hydroxypropyl acrylate, 4g quaternary ammonium salt compound B2 and 10g water. The dropping time of solution A is 50min.

[0086] Solution B is a solution prepared from 0.2g of sodium formaldehyde sulfoxylate, 1.5g of sodium hypophosphite and 42g of water. The dropping time of solution B is ~80min.

[0087] Example 3

[0088] Place 180g of allyl-terminated polyether monomer A1 and 300g of water in a four-necked flask, stir to dissolve, then add 0.01g of ferrous sulfate and 1.5g of hydrogen peroxide to obtain the bottom solution;

[0089] Adjust the reaction temperature to 30℃, and simultaneously add solution A and solution B to the bottom liquid in the four-necked flask. After the addition is complete, keep the temperature for 2 hours, and then add liquid alkali to neutralize and prepare the mud-blocking polycarboxylate superplasticizer.

[0090] Solution A is a solution prepared from 22g acrylic acid, 8g hydroxyethyl acrylate, 4g quaternary ammonium salt compound B3 and 10g water. The dropping time of solution A is 60min.

[0091] Solution B is a solution prepared from 0.2g sodium formaldehyde sulfoxylate, 0.22g thioglycolic acid and 42g water, with a dropping time of 80min.

[0092] Example 4

[0093] Place 90g of allyl-terminated polyether monomer A1, 90g of ethylene glycol monovinyl polyethylene glycol ether and 300g of water in a four-necked flask, stir to dissolve, then add 0.01g of ferrous sulfate and 1.5g of hydrogen peroxide to obtain the bottom solution.

[0094] Adjust the reaction temperature to 20–35°C. Add solutions A and B dropwise to a four-necked flask simultaneously. After the addition is complete, keep the temperature constant for 1.5 hours. Then, add liquid alkali to neutralize and prepare the mud-inhibiting polycarboxylate superplasticizer.

[0095] Solution A is a solution prepared from 22g acrylic acid, 8g hydroxyethyl acrylate, 4g quaternary ammonium salt compound B3 and 10g water. The dropping time of solution A is 70min.

[0096] Solution B is composed of 0.2g sodium formaldehyde sulfoxylate, 0.22g thioglycolic acid and 42g water, and is added dropwise over a period of 60-80 minutes.

[0097] Comparative Example 1

[0098] The difference from Example 1 is that the allyl-terminated polyether monomer A1 is replaced with an equal amount of 4-hydroxybutylvinyl polyoxyethylene ether.

[0099] Comparative Example 2

[0100] The difference from Example 1 is that no quaternary ammonium salt compound is added, and the amount of water is adjusted so that the solid content of the prepared mud-blocking polycarboxylate superplasticizer is the same as that in Example 1.

[0101] Comparative Example 3

[0102] Commercially available water-reducing agent KZJ-Point 400S.

[0103] The polycarboxylate superplasticizer samples synthesized in Examples 1-4 and Comparative Examples 1-2 were compared with the commercially available polycarboxylate superplasticizer in Comparative Example 3. The initial slump and spread of the concrete, as well as the slump and spread over time, were tested according to GB 8076-2008 "Concrete Admixtures" and GB / T 8077-2023 "Test Method for Homogeneity of Concrete Admixtures". The concrete mix proportion was: cement (Chunchi P·O 42.5R) 360 kg / m³. 3 860kg / m³ of manufactured sand 3 Gravel (5-20mm) 1000kg / m 3 172 kg / m³ of water 3 The results obtained by replacing cement with montmorillonite (according to the actual replacement ratio) are shown in Table 1.

[0104] Table 1. Concrete performance test results

[0105]

[0106] As can be seen from the results in Table 1, the initial spread of Comparative Example 3 changes significantly with the increase of dosage. When the dosage is small, the basic fluidity is poor, and when the dosage is increased, bleeding is likely to occur. The sensitivity range to dosage is small. In contrast, the polycarboxylate superplasticizer synthesized through Examples 1 and 2 shows that the spread changes less with the increase of dosage and the sensitivity range to dosage is large, meaning it is less sensitive to dosage.

[0107] At the same dosage, the addition of montmorillonite showed that the polycarboxylate superplasticizers synthesized in the examples and comparative examples had little impact on initial spread and spread over time, while Comparative Example 3 showed a significant loss. This indicates that the polycarboxylate superplasticizer synthesized in this invention has better mud-blocking properties and superior dispersion performance. The polycarboxylate superplasticizer prepared by this invention has low sensitivity to the dosage of superplasticizer, good mud-blocking properties, can improve the workability of concrete, has no adverse effects, wide applicability, and is quick and efficient to prepare.

[0108] It should be noted that the specific parameters or reagents in the above embodiments are specific or preferred embodiments under the concept of the present invention, and not limitations thereof; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.

Claims

1. A kind of anti-mud type polycarboxylate water reducer, it is characterized by, The preparation raw materials of the anti-mud type polycarboxylate superplasticizer include, in terms of weight parts: The allyl-terminated polyether monomer is allyl-terminated polyether monomer A1 or allyl-terminated polyether monomer A2; The preparation steps of the allyl-terminated polyether monomer A1 are as follows: 200 parts of 3,7-dimethyl-6-octene-1-ol is added into a four-necked flask, and 60 parts of potassium hydroxide is added, and the temperature is maintained in a water bath at 55°C under a nitrogen atmosphere; then, 100 parts of allyl chloride compound is slowly added dropwise, and constant temperature stirring is carried out at this temperature for 4 hours; after the dropwise addition is completed, constant temperature stirring is continued at the same temperature for 2 hours; finally, 5 parts of phosphoric acid is added for neutralization treatment, and then refined treatment is carried out, so that the allyl-terminated polyether monomer A1 is obtained; The preparation steps of the allyl-terminated polyether monomer A2 are as follows: 200 parts of 3,7-dimethyl-6-octene-1-ol is added into a four-necked flask, and 60 parts of potassium hydroxide is added, and the temperature is maintained in a water bath at 55°C under a nitrogen atmosphere; then, 100 parts of allyl chloride compound is slowly added dropwise, and constant temperature stirring is carried out at this temperature for 4 hours; after the dropwise addition is completed, constant temperature stirring is continued at the same temperature for 2 hours; finally, 5 parts of phosphoric acid is added for neutralization treatment, and then refined treatment is carried out, so that the allyl-terminated polyether monomer A1 is obtained; The quaternary ammonium salt compound is quaternary ammonium salt compound B1, quaternary ammonium salt compound B2 or quaternary ammonium salt compound B3; The preparation of the quaternary ammonium salt compound B1 is as follows: 1.6 g of dopamine is dissolved in 80 mL of acetic acid, and then 1.2 g of salicylaldehyde is dissolved in 100 mL of anhydrous methanol and added into the dopamine solution, and stirring is carried out for 18 hours; sodium hydroxide solution is used to adjust the pH value to 7, and then washing is carried out with a proper washing solvent, and vacuum drying is carried out, so that compound A is obtained; 1.6 g of compound A is dissolved in 100 mL of isopropyl alcohol, 10 mL of 40% sodium hydroxide is added, and reaction is carried out in a water bath at 55°C for 4 hours; then, 30 mL of 40 wt.% 3-chloro-2-hydroxypropyl trimethylammonium chloride aqueous solution is slowly added dropwise under the same water bath condition, the temperature is controlled at 60°C, and reaction is continued for 4-5 hours; finally, the obtained product is washed with an alcohol solution, and drying is carried out under vacuum, so that the quaternary ammonium salt compound B1 is obtained; The preparation steps of the quaternary ammonium salt compound B2 are as follows: 1.6 g of dopamine is dissolved in 80 mL of acetic acid, and then 2.0 g of 4-bromo-2-hydroxybenzaldehyde is dissolved in 100 mL of anhydrous methanol and added into the dopamine solution, and stirring is carried out for 24 hours; sodium hydroxide solution is used to adjust the pH value to neutral, and then washing is carried out with a proper washing solvent, and vacuum drying is carried out, so that compound A is obtained; 1.6 g of compound A is dissolved in 100 mL of isopropyl alcohol, 10 mL of 40% sodium hydroxide is added, and reaction is carried out in a water bath at 55°C for 4 hours; then, 30 mL of 40 wt.% 3-chloro-2-hydroxypropyl trimethylammonium chloride aqueous solution is slowly added dropwise under the same water bath condition, the temperature is controlled at 60°C, and reaction is continued for 4 hours; finally, the obtained product is washed with an alcohol solution, and drying is carried out under vacuum, so that the quaternary ammonium salt compound B2 is obtained; The preparation steps of the preparation of the quaternary ammonium salt compound B3 are as follows: Dissolve 1.6 g of dopamine in 80 mL of acetic acid, then dissolve 1.5 g of o-vanillin in 100 mL of anhydrous methanol and add the above dopamine solution, stir for 20 hours; adjust the pH value to neutral with sodium hydroxide solution, then wash with appropriate washing solvent and vacuum dry to obtain compound A; Then, dissolve 1.6 g of compound A in 100 mL of isopropyl alcohol, add 10 mL of 40% sodium hydroxide, and react in a water bath at 55°C for 4 h; then, slowly drop 30 mL of 40 wt.% 3-chloro-2-hydroxypropyl trimethyl ammonium chloride aqueous solution under the same water bath condition, control the temperature at 60°C, and continue to react for 5 hours; finally, wash the obtained product with alcohol solution and dry under vacuum condition to obtain the quaternary ammonium salt compound B3. 2.The anti-mud polycarboxylate water reducer according to claim 1, characterized in that, The raw materials for preparing the anti-mud polycarboxylic acid water reducing agent include, by weight fraction: Ferrous sulfate 0.01-0.02 parts.

3. A method for preparing the anti-mud polycarboxylate water reducer according to any one of claims 1 to 2, characterized by, The steps include: Stir the allyl-terminated polyether monomer, oxidizing agent and water uniformly to completely dissolve them to obtain a bottom solution; Drop A liquid and B liquid into the bottom solution, and continue to react for 1-2 h after the dropping is completed to obtain the anti-mud polycarboxylic acid water reducing agent; The A liquid is an aqueous solution of unsaturated acid monomer, unsaturated ester monomer and quaternary ammonium salt compound; The B liquid is an aqueous solution of reducing agent and chain transfer agent.

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