WO2024125545A1 - Quaternary ammonium salt polyether ester monomer, epeg type polycarboxylate water reducing agent, and preparation method therefor - Google Patents

Abstract

The present invention relates to the technical field of concrete admixtures, and in particular relates to a quaternary ammonium salt polyether ester monomer, an EPEG type polycarboxylate water reducing agent, and a preparation method therefor. The EPEG type polycarboxylate water reducing agent is formed by copolymerizing ethylene glycol monovinyl polyethylene glycol ether, an unsaturated amide monomer, an unsaturated carboxylic acid monomer, an unsaturated sulfonate, a silane monomer, dimethyl allyl phosphate chloride and a quaternary ammonium salt polyether ester monomer. The EPEG type polycarboxylate water reducing agent can effectively reduce the viscosity of concrete and improve the workability and flow rate of concrete, and has a significant improvement effect on the mechanical properties of concrete; and same has the advantages of a low amount, a high water-reducing rate, good workability, being capable of significantly reducing the viscosity of a slurry, wide applicability, etc.

Description

A quaternary ammonium salt polyether ester monomer, EPEG type polycarboxylate water reducer and preparation method thereof

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of Chinese patent application No. 202211621645.8, filed with the Chinese Patent Office on December 16, 2022, and entitled "A quaternary ammonium salt polyether ester monomer, EPEG type polycarboxylic acid water reducer and preparation method thereof", the entire contents of which are incorporated by reference in this application.

Technical Field

The invention relates to the technical field of concrete admixtures, and in particular to a quaternary ammonium salt polyether ester monomer, an EPEG type polycarboxylate water reducer and a preparation method thereof.

Background technique

In recent years, with the rise of large-scale buildings, some landmark buildings, super-high-rise buildings, bridges, tunnels, etc. have developed rapidly, and the requirements for the strength and durability of concrete structures have become increasingly higher; high-strength concrete with high overall strength and light weight has been widely used.

Since high-grade concrete uses a low water-cement ratio and a large amount of cementitious materials, there are problems such as high viscosity and slow flow rate of freshly mixed concrete in actual applications, which will bring a series of constraints to the transportation, pumping and construction of concrete. Therefore, technical personnel in this field start from the two core issues of concrete technology research, material composition and mix design: by optimizing material composition and adjusting mix design to improve the problems of high viscosity and slow flow rate of high-strength concrete.

In most industrial applications, the viscosity reduction performance of high-grade concrete is achieved mainly through three ways: increasing the amount of water reducer, selecting high-quality ultrafine powder, and optimizing particle grading. Increasing the amount of water reducer will not only increase production costs, but may also cause excessive slow setting of concrete, resulting in problems such as water seepage and bottoming, increasing the difficulty of construction and easily causing engineering accidents; the selection of high-quality ultrafine powder is limited by the regionality and quality stability of the adhesive, and optimizing the particle grading can improve the viscosity and fluidity of the initial high-strength concrete to a certain extent, but it cannot fundamentally solve the problem.

As the third generation of high-performance water reducers, polycarboxylate water reducer (PCE) has the characteristics of low dosage, high water reduction rate, and green environmental protection. It can significantly improve the working performance, mechanical properties and durability of concrete. It has gradually become the fifth indispensable component in the mix design of commercial concrete in addition to water, sand, stone, admixtures and cement. The differences in the synthetic raw materials and preparation methods of PCE determine its molecular structure, which in turn affects the working, mechanical and durability properties of concrete in engineering applications. Among them, ethylene glycol monovinyl polyethylene glycol ether (EPEG) is a new type of 6C polyether macromonomer, which has the advantages of high reactivity, good adaptability, strong structural designability, and easy regulation.

Therefore, in order to solve the problems of high viscosity, slow flow rate and difficult pumping of high-grade concrete, an EPEG type polycarboxylate water-reducing agent that can effectively reduce the viscosity of concrete and improve the workability of concrete is developed from the perspective of the designable structure of the polycarboxylate water-reducing agent, which is of great significance to the development of the construction industry.

Summary of the invention

In order to solve the problem of high viscosity and difficult pumping of high-grade concrete mentioned in the above background technology, the present invention provides an EPEG type polycarboxylate water reducer, and its technical solution is as follows:

The copolymer is polymerized by comonomers, wherein the comonomers include ethylene glycol monovinyl polyethylene glycol ether, unsaturated amide monomers, unsaturated carboxylic acid monomers, unsaturated sulfonates, silane monomers, allyl dimethyl phosphate chloride and quaternary ammonium salt polyether ester monomers;

The weight ratio of the ethylene glycol monovinyl polyethylene glycol ether, the unsaturated amide monomer, the unsaturated carboxylic acid monomer, the unsaturated sulfonate, the silane monomer, the dimethyl chloride allyl phosphate and the quaternary ammonium salt polyether ester monomer is (200-300): (4-8): (20-30): (4-8): (2-4): (4-6): (4-6).

In one embodiment, it is prepared by copolymerizing ethylene glycol monovinyl polyethylene glycol ether, unsaturated amide monomer, unsaturated carboxylic acid monomer, unsaturated sulfonate, silane monomer, allyl dimethyl phosphate chloride and quaternary ammonium salt polyether ester monomer at 10°C to 15°C.

In one embodiment, the unsaturated amide monomer is one or more combinations of acrylamide, N-(2-dimethylaminoethyl)acrylamide, N,N-methylenebisacrylamide, cyclopropaneamide, and caprolactam; The monomer is one or more combinations of acrylic acid, methacrylic acid, fumaric acid, maleic anhydride, and itaconic acid; the unsaturated sulfonate is one or more combinations of sodium methyl propylene sulfonate, sodium styrene sulfonate, 2-acrylamide-2-methylpropane sulfonic acid, and sodium dodecylbenzene sulfonate; the silane monomer is one or more combinations of vinyl trimethoxy silane, vinyl triethoxy silane, γ-methacryloxypropyl trimethoxy silane, KH550, and KH570; the quaternary ammonium salt polyether ester monomer is a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate.

In one embodiment, the chloroallyl dimethyl phosphate is prepared by esterification of dimethyl allyl phosphate and thionyl chloride; the weight ratio of the dimethyl allyl phosphate to the thionyl chloride is 100:(100-150).

In one embodiment, the preparation method of allyl dimethyl phosphate chloride is as follows: allyl dimethyl phosphate and solvent A are mixed, and a first catalyst and an inhibitor are added, the reaction system is heated to 40°C to 60°C, and thionyl chloride is added to the reaction system, and an esterification reaction is carried out at 40°C to 60°C for 2 to 4 hours and the temperature is kept for 3 to 5 hours to obtain the allyl dimethyl phosphate chloride; wherein the preparation of the allyl dimethyl phosphate chloride is carried out under a nitrogen atmosphere or an inert atmosphere; the weight ratio of the allyl dimethyl phosphate, solvent A, thionyl chloride, the first catalyst and the inhibitor is 100:(350-400):(100-150):(5-10):(0.5-1.0).

In one embodiment, the solvent A is one or more combinations of dichloromethane, chloroform, acetonitrile, and toluene; the first catalyst is one or more combinations of N'N dimethylformamide, pyridine, 4-dimethylaminopyridine, concentrated sulfuric acid, and ethyl sulfonic acid; the inhibitor is one or more combinations of hydroquinone, p-hydroxyanisole, phenothiazine, cuprous chloride, and ferric chloride.

In one embodiment, the preparation method of the quaternary ammonium salt polyether ester monomer is as follows: diethylene glycol monoallyl ether, amino acid, and a second catalyst are added to a reaction kettle and mixed evenly, reacted at 60° C. to 120° C. for 2 to 8 hours, and then cooled to room temperature, and then chloroform is added to the reaction kettle, mixed evenly, and allowed to stand for 12 to 24 hours to obtain diethylene glycol monoallyl ether carboxylate;

The obtained diethylene glycol monoallyl ether carboxylate is added into unsaturated acid anhydride and solvent A to dissolve, and then pyridine is added to react to obtain carboxyl-terminated diethylene glycol monoallyl ether carboxylate;

The obtained terminal carboxyl diethylene glycol monoallyl ether carboxylate is dissolved in N'N-dimethylformamide, thionyl chloride is added under nitrogen atmosphere or inert atmosphere, and the reaction system is heated to 40°C to 60°C for 5h to 12h to obtain acyl Chlorinated diethylene glycol monoallyl ether carboxylate;

The obtained acyl chloride diethylene glycol monoallyl ether carboxylate is added to ethanolamine, N'N-dimethylformamide and a mixture of quaternary ammonium salt compounds, and the reaction is carried out at 65°C to 90°C for 5 to 24 hours to obtain a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate, that is, a quaternary ammonium salt polyether ester monomer is obtained.

In one embodiment, the amino acid is one or more combinations of glutamic acid and aspartic acid; the solvent A is one or more combinations of dichloromethane, chloroform, acetonitrile, and toluene; the second catalyst is one or more combinations of thionyl chloride, copper sulfate, and tetrabutyl titanate; the unsaturated acid anhydride is one or more combinations of maleic anhydride and succinic anhydride; the quaternary ammonium salt compound is one or more combinations of ammonium chloride, methacryloyloxyethyltrimethylammonium chloride, dimethylalkylammonium chloride, benzyltrimethylammonium chloride, and chlormequat.

The present invention also provides a method for preparing the EPEG type polycarboxylate water reducer as described above, which comprises the following steps:

Dissolving ethylene glycol monovinyl polyethylene glycol ether in water; adding unsaturated amide monomer, sulfate, silane monomer, dimethyl chloroallyl phosphate and oxidant to the aqueous solution of ethylene glycol monovinyl polyethylene glycol ether to prepare a base solution, and controlling the temperature of the reaction system to be 10° C. to 15° C.;

Unsaturated carboxylic acid monomer, quaternary ammonium salt polyether ester monomer, unsaturated sulfonate, chain transfer agent and reducing agent are added to the base liquid, and copolymerization reaction is carried out at 10° C. to 15° C. to prepare the EPEG type polycarboxylate water reducer.

The present invention also provides a quaternary ammonium salt polyether ester monomer, and the preparation method thereof is as follows:

Add diethylene glycol monoallyl ether, amino acid and the second catalyst into a reaction kettle and mix them evenly, react at 60°C to 120°C for 2 to 8 hours and then cool to room temperature, then add chloroform into the reaction kettle, mix evenly and let stand for 12 to 24 hours to obtain diethylene glycol monoallyl ether carboxylate;

The obtained diethylene glycol monoallyl ether carboxylate is added into unsaturated acid anhydride and solvent A to dissolve, and then pyridine is added to react to obtain carboxyl-terminated diethylene glycol monoallyl ether carboxylate;

The obtained terminal carboxyl diethylene glycol monoallyl ether carboxylate is dissolved in N'N-dimethylformamide, thionyl chloride is added under a nitrogen atmosphere or an inert atmosphere, and the reaction system is heated to 40°C to 60°C for 5h to 12h to obtain acyl chloride diethylene glycol monoallyl ether carboxylate;

The obtained diethylene glycol monoallyl ether carboxylate acylation is added to ethanolamine, N'N-dimethylformamide and a mixture of quaternary ammonium salt compounds, and the mixture is reacted at 65°C to 90°C for 5 to 24 hours to obtain a quaternary ammonium salt polyether ester monomer.

Based on the above, compared with the prior art, the EPEG type polycarboxylate water reducer provided by the present invention has the following beneficial effects:

The EPEG type polycarboxylate water-reducing agent provided by the present invention can effectively reduce the viscosity of concrete, improve the workability and flow rate of concrete, and improve the mechanical properties of concrete; it has the advantages of low dosage, high water reduction rate, good workability, and can significantly reduce the viscosity of slurry.

Other features and beneficial effects of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other beneficial effects of the present invention can be achieved and obtained by the structures specifically pointed out in the description and claims.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments; the technical features designed in the different implementation modes of the present invention described below can be combined with each other as long as they do not conflict with each other; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

In the description of the present invention, it should be noted that all terms used in the present invention (including technical terms and scientific terms) have the same meanings as those generally understood by ordinary technicians in the field to which the present invention belongs, and should not be understood as limitations on the present invention; it should be further understood that the terms used in the present invention should be understood to have the same meanings as these terms in the context of this specification and in the relevant fields, and should not be understood in an idealized or overly formal sense, unless explicitly defined in this invention.

The present invention provides a preferred embodiment of the preparation method of the EPEG type polycarboxylate water reducer, which specifically comprises the following steps:

Step a) dissolving ethylene glycol monovinyl polyethylene glycol ether (EPEG) in water, placing in a reactor, and stirring thoroughly. Mix well;

Step b) adding unsaturated amide monomer, sulfate, silane monomer, dimethyl chloroallyl phosphate and oxidant to the aqueous solution of ethylene glycol monovinyl polyglycol ether in step a to prepare a base solution, and controlling the temperature to be 10° C. to 15° C.;

Step c) unsaturated carboxylic acid monomer, quaternary ammonium salt polyether ester monomer and water are prepared into solution A, and the solution is added dropwise to the base liquid for 50 to 80 minutes; unsaturated sulfonate, chain transfer agent and water are prepared into solution C, and the solution is added dropwise to the base liquid for 50 to 80 minutes; reducing agent and water are prepared into solution B, and the solution is added dropwise to the base liquid for 60 to 80 minutes; during the dropping process, the reaction system is copolymerized at 10° C. to 15° C., and the temperature is kept for 1 to 2 hours after the dropping is completed, and finally liquid alkali is added for neutralization to obtain the EPEG type polycarboxylate water reducer.

By weight, the raw materials in the copolymerization reaction system include 200-300 parts of ethylene glycol monovinyl polyethylene glycol ether, 4-8 parts of unsaturated amide monomers, 20-30 parts of unsaturated carboxylic acid monomers, 4-8 parts of unsaturated sulfonates, 2-4 parts of silane monomers, 4-6 parts of dimethyl chloroallyl phosphate, 4-6 parts of quaternary ammonium salt polyether ester monomers, 2.5-4.5 parts of oxidants, 0.2-0.4 parts of reducing agents, 1-1.5 parts of chain transfer agents, 1-2 parts of sulfates, and 350-400 parts of water. The overall acid-ether ratio is 1.0-2.0.

(1) For chloroallyl dimethyl phosphate, the present invention also provides a preferred embodiment of its preparation method as follows:

The chlorinated allyl dimethyl phosphate is prepared by esterification reaction of allyl dimethyl phosphate and thionyl chloride; the specific process is:

Allyl dimethyl phosphate and solvent A are stirred at room temperature for 0.5 to 2 hours to mix; and a first catalyst and a polymerization inhibitor are added, the reaction system is heated to 40°C to 60°C, thionyl chloride is added dropwise at this temperature for esterification reaction for 2 to 4 hours and kept warm for 3 to 5 hours, and after the reaction is completed, the allyl dimethyl phosphate is filtered and subjected to rotary evaporation to obtain the allyl dimethyl phosphate; wherein the preparation of the allyl dimethyl phosphate is carried out under a nitrogen atmosphere or an inert atmosphere throughout the reaction;

The weight ratio of allyl dimethyl phosphate, solvent A, thionyl chloride, the first catalyst and the polymerization inhibitor is 100: (350-400): (100-150): (5-10): (0.5-1.0).

The solvent A may be preferably one or more of dichloromethane, chloroform, acetonitrile, and toluene; the first catalyst may be preferably N'N-dimethylformamide, pyridine, 4-dimethylaminopyridine, concentrated sulfuric acid, ethylsulfonic acid, One or more combinations of; the inhibitor may preferably be one or more combinations of hydroquinone, p-hydroxyanisole, phenothiazine, cuprous chloride, and ferric chloride.

(2) For the quaternary ammonium salt polyether ester monomer, the present invention also provides a preferred embodiment of the preparation method of the quaternary ammonium salt polyether ester monomer as follows:

At room temperature, diethylene glycol monoallyl ether, amino acid and a second catalyst are added to a reaction kettle and stirred to mix evenly, reacted at 60°C to 120°C for 2 to 8 hours and then cooled to room temperature, and then chloroform is added to the reaction kettle and mixed evenly and allowed to stand for 12 to 24 hours, filtered, and the filtrate is evaporated under reduced pressure at 50°C to 65°C to remove chloroform, thereby separating and obtaining diethylene glycol monoallyl ether carboxylate; wherein the weight ratio of diethylene glycol monoallyl ether to chloroform is 1:(1 to 3);

The obtained diethylene glycol monoallyl ether carboxylate is added into unsaturated acid anhydride and solvent A, stirred and dissolved, and then pyridine is added dropwise to react to obtain carboxyl-terminated diethylene glycol monoallyl ether carboxylate; wherein the reaction temperature is controlled at (40° C. to 60° C.);

The obtained terminal carboxyl diethylene glycol monoallyl ether carboxylate is dissolved in N'N-dimethylformamide, thionyl chloride is added under a nitrogen atmosphere or an inert atmosphere, the reaction system is heated to 40°C to 60°C for 5h to 12h, the thionyl chloride is removed by concentration under reduced pressure, and the product is washed with ether to obtain acyl chloride diethylene glycol monoallyl ether carboxylate;

The obtained acyl chloride diethylene glycol monoallyl ether carboxylate is added to ethanolamine, N'N-dimethylformamide and a mixture of quaternary ammonium salt compounds, and the reaction is carried out at 65°C to 90°C for 5 to 24 hours. After separation and purification of the reaction liquid, a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate is obtained, i.e., a quaternary ammonium salt polyether ester monomer is obtained.

The weight ratio of diethylene glycol monoallyl ether, amino acid, unsaturated acid anhydride, thionyl chloride and quaternary ammonium salt compound is (100-200): (65-130): (60-120): (200-400): (2-6);

Among them, the amino acid can be preferably one or more combinations of glutamic acid and aspartic acid; the solvent A can be preferably one or more combinations of dichloromethane, chloroform, acetonitrile and toluene; the second catalyst can be preferably one or more combinations of thionyl chloride, copper sulfate and tetrabutyl titanate; the unsaturated acid anhydride can be preferably one or more combinations of maleic anhydride and succinic anhydride; the quaternary ammonium salt compound can be preferably one or more combinations of ammonium chloride, methacryloyloxyethyl trimethylammonium chloride, dimethyl alkyl ammonium chloride, benzyl trimethyl ammonium chloride and chlormequat. More preferably, the amino acid Aspartic acid is selected; the solvent A is chloroform; the second catalyst is copper sulfate; the unsaturated acid anhydride is succinic anhydride; and the quaternary ammonium salt compound is dimethyl alkyl ammonium chloride.

(3) For other comonomers:

The unsaturated amide monomer may preferably be one or more combinations of acrylamide, N-(2-dimethylaminoethyl)acrylamide, N,N-methylenebisacrylamide, cyclopropaneamide, and caprolactam; the unsaturated carboxylic acid monomer may preferably be one or more combinations of acrylic acid, methacrylic acid, fumaric acid, maleic anhydride, and itaconic acid; the unsaturated sulfonate may preferably be one or more combinations of sodium methyl propylene sulfonate, sodium styrene sulfonate, 2-acrylamide-2-methylpropane sulfonic acid, and sodium dodecylbenzene sulfonate; the silane monomer may preferably be one or more combinations of vinyl trimethoxy silane, vinyl triethoxy silane, γ-methacryloxypropyl trimethoxy silane, KH550, and KH570.

(4) For other copolymerization raw materials:

In step a), the reducing agent is preferably one or more combinations of sodium sulfite, bleaching powder, sodium bisulfite, and sodium hypophosphite, wherein sodium hypophosphite can also be used as a chain transfer agent; the oxidizing agent may be preferably one or more combinations of hydrogen peroxide, sodium peroxide, potassium peroxide, magnesium peroxide, sodium persulfate, ammonium persulfate, sodium dichromate, potassium dichromate, and potassium permanganate; the chain transfer agent may be preferably one or more combinations of thioglycolic acid, sodium hypophosphite, trisodium phosphate, mercaptopropionic acid, mercaptoethanol, and thioglycolic acid. In step b), the sulfate is preferably ferrous sulfate. Further preferably, the silane monomer is KH550; the unsaturated carboxylic acid monomer is acrylic acid; and the oxidizing agent is hydrogen peroxide.

The present invention also provides the following embodiments and comparative examples:

Example 1

(1) Preparation of allyl dimethyl phosphate A:

100g of allyl dimethyl phosphate and 350g of dichloromethane solvent were put into a four-necked flask, stirred evenly, and then 5g of catalyst DMF and 0.5g of inhibitor phenothiazine were added. Then the temperature was raised to 45°C during stirring, and 125g of thionyl chloride was added dropwise at this temperature for about 3h, and kept warm for 4h in condensation reflux, and the whole process was reacted in a nitrogen atmosphere. After the reaction was completed, filtration and rotary evaporation were performed to obtain allyl dimethyl phosphate A.

(2) Preparation of blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate, i.e., quaternary ammonium salt polyether ester monomer:

Step a) 100g of diethylene glycol monoallyl ether with a molecular weight of 1200, 67g of L-aspartic acid and 0.85g of a catalyst (copper sulfate) are added to a reactor, stirred evenly, placed at 100°C for reaction for 6 hours and then cooled to room temperature, then 250ml of chloroform is added to the reactor, stirred evenly and allowed to stand for 12 hours and then filtered, and the filtrate is evaporated under reduced pressure at 60°C to remove chloroform, thereby obtaining diethylene glycol monoallyl ether aspartic acid ester;

Step b) adding 100g of diethylene glycol monoallyl ether carboxylate and 60g of succinic anhydride to 300ml of chloroform and stirring to dissolve, heating to 60°C, and adding 15g of pyridine dropwise at the same temperature for 3h, adding chloroform and saturated sodium bicarbonate solution for extraction after the reaction, drying the organic phase and washing with ether to obtain terminal carboxyl diethylene glycol monoallyl ether carboxylate, then dissolving it in N,N-dimethylformamide, adding 200mL of thionyl chloride dropwise in a nitrogen atmosphere, heating to 60°C for reaction for 8h, concentrating under reduced pressure to remove thionyl chloride, and washing the product with ether to obtain acyl chloride diethylene glycol monoallyl ether carboxylate;

Step c) 100g of diethylene glycol monoallyl ether carboxylate acyl chloride is added to a four-necked flask, and after adding 100ml of DMF solution and dissolving repeatedly, the temperature is raised to 80°C, 5.8g of ethanolamine is added, and the mixture is condensed and refluxed for 12h, and then 2.2g of dimethyl alkyl ammonium chloride and 20ml of DMF solution are added dropwise for 1h, and the mixture is condensed and refluxed for 12h, all of which are carried out under a nitrogen atmosphere. After the reaction is completed, the reaction product is filtered and rotary evaporated to prepare a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate.

(3) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water into a four-necked flask, stir to dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration is 1%), 2g of KH550, 1g of sodium hypophosphite, and 4g of dimethyl chloroallyl phosphate A, stir well, adjust the temperature to 10-15°C, and set aside.

20g acrylic acid, 4g quaternary ammonium salt polyether ester monomer and 30g water are prepared into liquid A; 4g AMPS, 0.8g mercaptopropionic acid monomer and 50g water are prepared into liquid B; 0.25g bleaching powder and 50g water are prepared into liquid C. Before adding, 2.5g hydrogen peroxide is added to a four-necked flask and stirred for 5 minutes before adding simultaneously, wherein liquids A and B are added for 50min, and liquid C is added for 60min; after the addition is completed, the temperature is kept for 1h, and the temperature does not exceed 25℃ throughout the process. After the insulation is completed, liquid is added to adjust the pH value of the solution to 5.0-6.5, and an EPEG type polycarboxylic acid water reducer is obtained.

Example 2

(1) Preparation of allyl dimethyl phosphate B:

100g of allyl dimethyl phosphate, 300g of dichloromethane and 50g of acetonitrile solvent were put into a four-necked flask device, stirred evenly, and then 4g of DMF, 1.5g of pyridine, 0.3g of phenothiazine and 0.25g of ferrous chloride were added as catalysts. Then, the temperature was raised to 45°C during stirring, and 125g of thionyl chloride was added dropwise at this temperature for about 3h, and the temperature was kept for 4h in condensation reflux, and the whole process was reacted in a nitrogen atmosphere. After the reaction was completed, filtration and rotary evaporation were performed to obtain allyl dimethyl phosphate B.

(2) Preparation of blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate, i.e., quaternary ammonium salt polyether ester monomer:

Step a) 100g of diethylene glycol monoallyl ether with a molecular weight of 1200, 67g of L-aspartic acid and 0.85g of a catalyst (copper sulfate) are added to a reactor, stirred evenly, placed at 100°C for reaction for 6 hours and then cooled to room temperature, then 250ml of chloroform is added to the reactor, stirred evenly and allowed to stand for 12 hours and then filtered, and the filtrate is evaporated under reduced pressure at 60°C to remove chloroform, thereby obtaining diethylene glycol monoallyl ether aspartic acid ester;

Step b) adding 100g of diethylene glycol monoallyl ether carboxylate and 60g of succinic anhydride to 300ml of chloroform and stirring to dissolve, heating to 60°C, and adding 15g of pyridine dropwise at the same temperature for 3h, adding chloroform and saturated sodium bicarbonate solution for extraction after the reaction, drying the organic phase and washing with ether to obtain terminal carboxyl diethylene glycol monoallyl ether carboxylate, then dissolving it in N,N-dimethylformamide, adding 200mL of thionyl chloride dropwise in a nitrogen atmosphere, heating to 60°C for reaction for 8h, concentrating under reduced pressure to remove thionyl chloride, and washing the product with ether to obtain acyl chloride diethylene glycol monoallyl ether carboxylate;

Step c) 100g of diethylene glycol monoallyl ether carboxylate acyl chloride is added to a four-necked flask, and after adding 100ml of DMF solution and dissolving repeatedly, the temperature is raised to 80°C, 5.8g of ethanolamine is added, and the mixture is condensed and refluxed for 12h, and then 2.2g of dimethyl alkyl ammonium chloride and 20ml of DMF solution are added dropwise for 1h, and the mixture is condensed and refluxed for 12h, all of which are carried out under a nitrogen atmosphere. After the reaction is completed, the reaction product is filtered and rotary evaporated to prepare a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate.

(3) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water to a four-necked flask, stir and dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration of 1%), 2g of KH550, 1g of sodium hypophosphite, and 4g of dimethyl chloroallyl phosphate B, stir well, adjust the temperature to 10-15°C, and set aside. Prepare liquid A by mixing 20g of acrylic acid, 4g of quaternary ammonium salt polyether ester monomer, and 30g of water; prepare liquid B by mixing 4g of AMPS, 0.8g of mercaptopropionic acid monomer, and 50g of water; prepare liquid C by mixing 0.25g of bleaching powder and 50g of water. Before adding, add 2.5g of hydrogen peroxide to a four-necked flask, stir for 5 minutes, and then start adding simultaneously, with liquids A and B added for 50min, and liquid C added for 60min; keep warm for 1h after the addition is completed, and the temperature does not exceed 25°C throughout the process. After the heat preservation is completed, liquid is added to adjust the pH value of the solution to be controlled at 5.0-6.5 to obtain an EPEG type polycarboxylate water reducer.

Example 3

(1) Preparation of allyl dimethyl phosphate B:

100g of allyl dimethyl phosphate, 300g of dichloromethane and 50g of acetonitrile solvent were put into a four-necked flask device, stirred evenly, and then 4g of DMF, 1.5g of pyridine, 0.3g of phenothiazine and 0.25g of ferrous chloride were added as catalysts. Then, the temperature was raised to 45°C during stirring, and 125g of thionyl chloride was added dropwise at this temperature for about 3h, and the temperature was kept for 4h in condensation reflux, and the whole process was reacted in a nitrogen atmosphere. After the reaction was completed, filtration and rotary evaporation were performed to obtain allyl dimethyl phosphate B.

(2) Preparation of blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate, i.e., quaternary ammonium salt polyether ester monomer:

Step a) 100g of diethylene glycol monoallyl ether with a molecular weight of 1200, 67g of L-aspartic acid and 0.85g of a catalyst (copper sulfate) are added to a reactor, stirred evenly, placed at 100°C for reaction for 6 hours and then cooled to room temperature, then 250ml of chloroform is added to the reactor, stirred evenly and allowed to stand for 12 hours and then filtered, and the filtrate is evaporated under reduced pressure at 60°C to remove chloroform, thereby obtaining diethylene glycol monoallyl ether aspartic acid ester;

Step b) 100g of diethylene glycol monoallyl ether carboxylate and 60g of succinic anhydride were added to 300ml of chloroform and stirred to dissolve, and then the temperature was raised to 60°C, and 15g of pyridine was added dropwise at this temperature for 3h. After the reaction, chloroform and saturated sodium bicarbonate solution were added for extraction, and the organic phase was dried and washed with ether to obtain terminal carboxyl diethylene glycol monoallyl ether carboxylate, which was then dissolved in N,N-dimethylformamide, and 200mL of chlorinated amine was added dropwise in a nitrogen atmosphere. sulfone, heating to 60°C for 8h, concentrating under reduced pressure to remove thionyl chloride, washing the product with ether to obtain diethylene glycol monoallyl ether carboxylate;

Step c) 100g of diethylene glycol monoallyl ether carboxylate acyl chloride is added to a four-necked flask, and after adding 100ml of DMF solution and dissolving repeatedly, the temperature is raised to 80°C, 5.8g of ethanolamine is added, and the mixture is condensed and refluxed for 12h, and then 2.2g of dimethyl alkyl ammonium chloride and 20ml of DMF solution are added dropwise for 1h, and the mixture is condensed and refluxed for 12h, all of which are carried out under a nitrogen atmosphere. After the reaction is completed, the reaction product is filtered and rotary evaporated to prepare a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate.

(3) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water to a four-necked flask, stir and dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration of 1%), 1g of sodium hypophosphite, and 4g of dimethyl chloroallyl phosphate B, stir well, adjust the temperature to 10-15℃, and set aside. Prepare 20g of acrylic acid, 4g of quaternary ammonium salt polyether ester monomer and 30g of water to make liquid A; prepare 4g of AMPS, 0.8g of mercaptopropionic acid monomer and 50g of water to make liquid B; prepare 0.25g of bleaching powder and 50g of water to make liquid C. Before adding, add 2.5g of hydrogen peroxide to a four-necked flask, stir for 5 minutes, and then start to add simultaneously, wherein liquids A and B are added for 50min, and liquid C is added for 60min; after the addition is completed, keep warm for 1h, and the temperature does not exceed 25℃ throughout the process. After the insulation is completed, add liquid to adjust the pH value of the solution to 5.0-6.5 to obtain EPEG type polycarboxylic acid water reducer.

Example 4

(1) Preparation of allyl dimethyl phosphate B:

100g of allyl dimethyl phosphate, 300g of dichloromethane and 50g of acetonitrile solvent were put into a four-necked flask device, stirred evenly, and then 4g of DMF, 1.5g of pyridine, 0.3g of phenothiazine and 0.25g of ferrous chloride were added as catalysts. Then, the temperature was raised to 45°C during stirring, and 125g of thionyl chloride was added dropwise at this temperature for about 3h, and the temperature was kept for 4h in condensation reflux, and the whole process was reacted in a nitrogen atmosphere. After the reaction was completed, filtration and rotary evaporation were performed to obtain allyl dimethyl phosphate B.

(2) Preparation of blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate, i.e., quaternary ammonium salt polyether ester monomer:

Step a) 100g of diethylene glycol monoallyl ether with a molecular weight of 1200, 67g of L-aspartic acid and 0.85g of a catalyst (copper sulfate) are added to a reactor, stirred evenly, placed at 100°C for reaction for 6 hours and then cooled to room temperature, then 250ml of chloroform is added to the reactor, stirred evenly and allowed to stand for 12 hours and then filtered, and the filtrate is evaporated under reduced pressure at 60°C to remove chloroform, thereby obtaining diethylene glycol monoallyl ether aspartic acid ester;

Step b) adding 100g of diethylene glycol monoallyl ether carboxylate and 60g of succinic anhydride to 300ml of chloroform and stirring to dissolve, heating to 60°C, and adding 15g of pyridine dropwise at the same temperature for 3h, adding chloroform and saturated sodium bicarbonate solution for extraction after the reaction, drying the organic phase and washing with ether to obtain terminal carboxyl diethylene glycol monoallyl ether carboxylate, then dissolving it in N,N-dimethylformamide, adding 200mL of thionyl chloride dropwise in a nitrogen atmosphere, heating to 60°C for reaction for 8h, concentrating under reduced pressure to remove thionyl chloride, and washing the product with ether to obtain acyl chloride diethylene glycol monoallyl ether carboxylate;

Step c) 100g of diethylene glycol monoallyl ether carboxylate acyl chloride is added to a four-necked flask, and after adding 100ml of DMF solution and dissolving repeatedly, the temperature is raised to 80°C, 5.8g of ethanolamine is added, and the mixture is condensed and refluxed for 12h, and then 2.2g of dimethyl alkyl ammonium chloride and 20ml of DMF solution are added dropwise for 1h, and the mixture is condensed and refluxed for 12h, all of which are carried out under a nitrogen atmosphere. After the reaction is completed, the reaction product is filtered and rotary evaporated to prepare a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate.

(3) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water to a four-necked flask, stir and dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration is 1%), 2g of KH550, and 4g of dimethyl chloroallyl phosphate B, stir well, and adjust the temperature to 10-15°C for use. 20g of acrylic acid, 4g of quaternary ammonium salt polyether ester monomer and 30g of water are prepared into liquid A; 4g of AMPS, 1.2g of mercaptopropionic acid monomer and 50g of water are prepared into liquid B; 0.25g of bleaching powder and 50g of water are prepared into liquid C. Before adding, add 2.5g of hydrogen peroxide to a four-necked flask, stir for 5 minutes, and then start to add simultaneously, wherein liquids A and B are added for 50min, and liquid C is added for 60min; after the addition is completed, keep warm for 1h, and the temperature does not exceed 25°C throughout the process. After the insulation is completed, add liquid to adjust the pH value of the solution to 5.0-6.5 to obtain an EPEG type polycarboxylic acid water reducer.

Example 5

(1) Preparation of allyl dimethyl phosphate B:

100g of allyl dimethyl phosphate, 300g of dichloromethane and 50g of acetonitrile solvent were put into a four-necked flask device, stirred evenly, and then 4g of DMF, 1.5g of pyridine, 0.3g of phenothiazine and 0.25g of ferrous chloride were added as catalysts. Then, the temperature was raised to 45°C during stirring, and 125g of thionyl chloride was added dropwise at this temperature for about 3h, and the temperature was kept for 4h in condensation reflux, and the whole process was reacted in a nitrogen atmosphere. After the reaction was completed, filtration and rotary evaporation were performed to obtain allyl dimethyl phosphate B.

(2) Preparation of blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate, i.e., quaternary ammonium salt polyether ester monomer:

Step a) 100g of diethylene glycol monoallyl ether with a molecular weight of 1200, 67g of L-aspartic acid and 0.85g of a catalyst (copper sulfate) are added to a reactor, stirred evenly, placed at 100°C for reaction for 6 hours and then cooled to room temperature, then 250ml of chloroform is added to the reactor, stirred evenly and allowed to stand for 12 hours and then filtered, and the filtrate is evaporated under reduced pressure at 60°C to remove chloroform, thereby obtaining diethylene glycol monoallyl ether aspartic acid ester;

Step b) adding 100g of diethylene glycol monoallyl ether carboxylate and 60g of succinic anhydride to 300ml of chloroform and stirring to dissolve, heating to 60°C, and adding 15g of pyridine dropwise at the temperature for 3h, adding chloroform and saturated sodium bicarbonate solution for extraction after the reaction, drying the organic phase and washing with ether to obtain terminal carboxyl diethylene glycol monoallyl ether carboxylate, then dissolving it in N,N-dimethylformamide, adding 200mL of thionyl chloride dropwise in a nitrogen atmosphere, heating to 60°C for reaction for 8h, concentrating under reduced pressure to remove thionyl chloride, and washing the product with ether to obtain acyl chloride diethylene glycol monoallyl ether carboxylate;

Step c) 100g of diethylene glycol monoallyl ether carboxylate acyl chloride is added to a four-necked flask, and after adding 100ml of DMF solution and dissolving repeatedly, the temperature is raised to 80°C, 5.8g of ethanolamine is added, and the mixture is condensed and refluxed for 12h, and then 2.2g of dimethyl alkyl ammonium chloride and 20ml of DMF solution are added dropwise for 1h, and the mixture is condensed and refluxed for 12h, all of which are carried out under a nitrogen atmosphere. After the reaction is completed, the reaction product is filtered and rotary evaporated to prepare a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate.

(3) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water to a four-necked flask, stir and dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration is 1%), 2g of KH550, and 4g of dimethyl chloroallyl phosphate B, stir well, adjust the temperature to 10-15°C, and set aside. Prepare liquid A with 20g of acrylic acid, 4g of quaternary ammonium salt polyether ester monomer, and 30g of water; prepare liquid B with 4g of sodium methyl propylene sulfonate, 1.2g of mercaptopropionic acid monomer, and 50g of water; prepare liquid C with 0.25g of bleaching powder and 50g of water. Before adding, add 2.5g of hydrogen peroxide to a four-necked flask, stir for 5 minutes, and then start to add simultaneously, wherein liquid A and liquid B are added for 50min, and liquid C is added for 60min; after the addition is completed, keep warm for 1h, and the temperature does not exceed 25°C throughout the process. After the heat preservation is completed, liquid is added to adjust the pH value of the solution to be controlled at 5.0-6.5 to obtain an EPEG type polycarboxylate water reducer.

Comparative Example 1

Commercially available polycarboxylic acid water reducer. Specifically, the Point-R brand produced by KZJ New Materials Group.

Comparative Example 2

(1) Preparation of blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate, i.e., quaternary ammonium salt polyether ester monomer:

Step a) 100g of diethylene glycol monoallyl ether with a molecular weight of 1200, 67g of L-aspartic acid and 0.85g of a catalyst (copper sulfate) are added to a reactor, stirred evenly, placed at 100°C for reaction for 6 hours and then cooled to room temperature, then 250ml of chloroform is added to the reactor, stirred evenly and allowed to stand for 12 hours and then filtered, and the filtrate is evaporated under reduced pressure at 60°C to remove chloroform, thereby obtaining diethylene glycol monoallyl ether aspartic acid ester;

Step b) adding 100g of diethylene glycol monoallyl ether carboxylate and 60g of succinic anhydride to 300ml of chloroform and stirring to dissolve, heating to 60°C, and adding 15g of pyridine dropwise at the same temperature for 3h, adding chloroform and saturated sodium bicarbonate solution for extraction after the reaction, drying the organic phase and washing with ether to obtain terminal carboxyl diethylene glycol monoallyl ether carboxylate, then dissolving it in N,N-dimethylformamide, adding 200mL of thionyl chloride dropwise in a nitrogen atmosphere, heating to 60°C for reaction for 8h, concentrating under reduced pressure to remove thionyl chloride, and washing the product with ether to obtain acyl chloride diethylene glycol monoallyl ether carboxylate;

Step c) 100 g of diethylene glycol monoallyl ether carboxylate was added to a four-necked flask, and after repeated dissolution with 100 ml of DMF solution, the temperature was raised to 80° C., 5.8 g of ethanolamine was added, and the mixture was condensed and refluxed for 12 h, and then 2.2 g of After dimethyl alkyl ammonium chloride and 20 ml of DMF solution were added dropwise for 1 hour, the mixture was condensed and refluxed for 12 hours, all under a nitrogen atmosphere. After the reaction was completed, the reaction product was filtered and rotary evaporated to prepare a blocked quaternary ammonium salt of diethylene glycol monoallyl ether carboxylate.

(2) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water into a four-necked flask, stir to dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration is 1%), 2g of KH550, and 1g of sodium hypophosphite, stir well and adjust the temperature to 10-15°C for use.

20g acrylic acid, 4g quaternary ammonium salt polyether ester monomer and 30g water are prepared into liquid A; 4g AMPS, 0.8g mercaptopropionic acid monomer and 50g water are prepared into liquid B; 0.25g bleaching powder and 50g water are prepared into liquid C. Before adding, add 2.5g hydrogen peroxide into a four-necked flask and stir for 5 minutes before adding simultaneously, wherein liquid A and liquid B are added for 50min, and liquid C is added for 60min; after the addition is completed, keep warm for 1h, and the temperature does not exceed 25℃ throughout the process. After the insulation is completed, add liquid to adjust the pH value of the solution to 5.0-6.5, and obtain EPEG type polycarboxylic acid water reducer.

Comparative Example 3

(1) Preparation of allyl dimethyl phosphate B:

100g of allyl dimethyl phosphate, 300g of dichloromethane and 50g of acetonitrile solvent were put into a four-necked flask device, stirred evenly, and then 4g of DMF, 1.5g of pyridine, 0.3g of phenothiazine and 0.25g of ferrous chloride were added as catalysts. Then, the temperature was raised to 45°C during stirring, and 125g of thionyl chloride was added dropwise at this temperature for about 3h, and the temperature was kept for 4h in condensation reflux, and the whole process was reacted in a nitrogen atmosphere. After the reaction was completed, filtration and rotary evaporation were performed to obtain allyl dimethyl phosphate B.

(2) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water into a four-necked flask, stir to dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration is 1%), 2g of KH550, 1g of sodium hypophosphite, and 4g of dimethyl chloroallyl phosphate B, stir well, adjust the temperature to 10-15°C, and set aside.

20g acrylic acid and 30g water were mixed into liquid A; 4g AMPS, 0.8g mercaptopropionic acid monomer and 50g water were mixed into liquid B Liquid; 0.25g of bleaching powder and 50g of water are prepared into liquid C. Before adding, 2.5g of hydrogen peroxide is added to a four-necked flask and stirred for 5 minutes before adding simultaneously, wherein liquids A and B are added for 50min, and liquid C is added for 60min; after the addition is completed, the temperature is kept for 1h, and the temperature does not exceed 25°C throughout the process. After the insulation is completed, liquid is added to adjust the pH value of the solution to 5.0-6.5, and an EPEG type polycarboxylate water reducer is obtained.

Comparative Example 4

(1) Preparation of EPEG type polycarboxylate water reducer:

Add 200g of ethylene glycol monovinyl polyglycol ether and 200g of deionized water into a four-necked flask, stir to dissolve, then add 4g of acrylamide, 1g of ferrous sulfate (concentration is 1%), 2g of KH550, and 1g of sodium hypophosphite, stir well and adjust the temperature to 10-15°C for use.

20g acrylic acid and 30g water were prepared into liquid A; 4g AMPS, 0.8g mercaptopropionic acid monomer and 50g water were prepared into liquid B; 0.25g bleaching powder and 50g water were prepared into liquid C. Before adding, 2.5g hydrogen peroxide was added to a four-necked flask and stirred for 5 minutes before adding simultaneously, with liquids A and B added for 50min and liquid C added for 60min; after adding, the temperature was kept warm for 1h, and the temperature did not exceed 25℃. After the insulation, liquid was added to adjust the pH value of the solution to 5.0-6.5, and an EPEG type polycarboxylic acid water reducer was obtained.

Runfeng cement (PO 42.5), machine-made sand and crushed stone were used as raw materials. The concrete mix ratio was: cement 360kg/m ³ , fly ash (grade II) 80kg/m ³ , mineral powder 60kg/m ³ , sand 750kg/m ³ , gravel 980kg/m ³ , and the expansion was controlled at 650±20mm. The polycarboxylate water-reducing agent samples of the embodiment and the comparative example were respectively tested for initial slump and expansion of the concrete, slump and expansion over time, emptying time of the inverted slump bucket, and emptying time of the inverted slump bucket over time according to GB8076-2008 "Concrete Admixtures", GB 8077-2012 "Test Method for Homogeneity of Concrete Admixtures" and GJ281-2012 "Technical Specification for Application of High-Strength Concrete". The test results are shown in Table 1:

Table 1 Performance comparison

From Table 1 we can see that:

The experimental results of Examples 1-5 and Comparative Examples 1-4 show that in the concrete experiment, when the initial expansion degree is controlled within a certain range, the polycarboxylate water-reducing agent prepared by the embodiment of the present invention has a much lower dosage than the reference sample (Comparative Example 1) during the doping process, and the emptying time of the embodiment is significantly lower than that of the comparative example, which can indicate that the application performance (emptying time) of the concrete of the embodiment of the present invention is much better than that of the reference sample and the comparative example.

The only difference between Comparative Example 2 and Example 4 is that no dimethyl chloroallyl phosphate is added in the copolymerization reaction. Compared with Example 4, the emptying time of Comparative Example 2 is significantly increased, indicating that the viscosity of the concrete in Comparative Example 2 is large. This is because the phosphate introduced in the scheme of the present invention has a strong adsorption capacity for cement, which is beneficial to its wetting and adsorption of cement, improves the dispersibility and fluidity of concrete, and reduces the viscosity of concrete.

The only difference between Comparative Example 3 and Example 4 is that no quaternary ammonium salt polyether ester monomer is added in the copolymerization reaction. Compared with Example 4, the emptying time of Comparative Example 3 is significantly increased, indicating that the concrete viscosity of Comparative Example 3 is large. This is because the quaternary ammonium salt group introduced in the scheme of the present invention can be electrostatically adsorbed on the surface of cement particles, thereby showing good dispersibility and fluidity, and effectively reducing the viscosity of the concrete.

The only difference between Comparative Example 4 and Example 4 is that no dimethyl chlorinated allyl phosphate and quaternary ammonium salt polyether ester monomer are added in the copolymerization reaction. Compared with Example 4, the emptying time of Comparative Example 4 is significantly increased, indicating that the concrete of Comparative Example 4 The high viscosity indicates that the phosphate and quaternary ammonium salt groups introduced in the solution of the present invention can be effectively adsorbed on the surface of cement particles through electrostatic adsorption and steric hindrance, indicating that it has good fluidity and dispersibility.

The EPEG type polycarboxylate water-reducing agent provided in Examples 1-5 of the present invention has a short emptying time, which can effectively reduce the viscosity of concrete, and the reduced viscosity of concrete can improve the flow rate of concrete, so its construction performance becomes better and the workability of concrete is improved; under the condition of achieving the same expansion degree, the dosage and emptying time in the embodiment are lower than those in the comparative example; at the same time, the mechanical properties of the concrete in Examples 1-5 of the present invention remain good; in summary, the EPEG type polycarboxylate water-reducing agent prepared in the embodiment of the present invention has good viscosity reduction performance, can improve the workability and flow rate of concrete, and at the same time, it has a significant improvement on the mechanical properties of concrete without other adverse effects; the EPEG type polycarboxylate water-reducing agent has the advantages of wide applicability, simple and fast preparation process and high efficiency.

The EPEG type polycarboxylate water reducer and its preparation method provided by the present invention at least include the following design concepts, action mechanisms and beneficial effects:

1. The present invention is based on the designable structure of the polycarboxylate water-reducing agent, and the EPEG type polycarboxylate water-reducing agent is developed by molecular design. The EPEG type polycarboxylate water-reducing agent is prepared by copolymerizing ethylene glycol monovinyl polyethylene glycol ether (EPEG), unsaturated amide monomers, unsaturated carboxylic acid monomers, unsaturated sulfonates, silane monomers, dimethyl chloroallyl phosphate and quaternary ammonium salt polyether ester monomers, and phosphate, carboxylate, amide, sulfonic acid, quaternary ammonium salt and silane groups are introduced into the polymer molecular structure.

Among them, phosphate has a strong adsorption capacity for cement, and works synergistically with carboxylate, which is beneficial to its wetting and adsorption of cement, and improves the dispersibility and fluidity of concrete; amide group protects carboxyl group to a certain extent, reduces the initial adsorption rate of carboxyl group in water reducer to cement particles, and gradually hydrolyzes in alkaline environment, and then releases carboxyl group, which will continue to slowly adsorb cement particles, thus showing good dispersibility and fluidity. Silane group can introduce double-bonded alkoxysilane into the main chain of PCEs through free radical polymerization, and can chemically bond with cementitious materials after hydrolysis, and its binding ability is stronger than electrostatic adsorption, so the solid-liquid interface energy between cementitious material particles and liquid phase is low, the bound water on the surface of cementitious material particles is less, the water film thickness is small, and there is more free water in the system, thus showing good dispersibility and fluidity. Quaternary ammonium salt group can be electrostatically adsorbed on the surface of cement particles, thereby showing good dispersibility.

By combining the above-mentioned phosphate group, carboxylate group, amide group, sulfonic acid group, quaternary ammonium salt group and silane group, the EPEG type polycarboxylate water reducer has the advantages of low dosage, good workability and the ability to significantly reduce the slurry viscosity.

2. The EPEG type polycarboxylate water reducer provided by the present invention has the advantages of low dosage, high water reduction rate, good workability, and can significantly reduce the viscosity of the slurry and has a wide adaptability to the mud content of sand and gravel.

3. The EPEG type polycarboxylate water reducer provided by the present invention has common and easily available raw materials required for its preparation process, low cost, and the preparation process is simple, fast, green and environmentally friendly.

In summary, the present invention develops the above-mentioned EPEG type polycarboxylate water-reducing agent from the perspective of the designable structure of the polycarboxylate water-reducing agent, and the EPEG type polycarboxylate water-reducing agent can effectively reduce the viscosity of concrete and improve the workability of concrete; it has the advantages of high water reduction, good concrete performance, good adaptability, simple process, etc. And its preparation method process has the advantages of cheap and easy availability of the required raw materials, environmental friendliness, easy control of reaction conditions, simple production process, low production cost, short synthesis time, high efficiency, low energy consumption, etc.

It should be noted:

"Ethylene glycol monovinyl polyethylene glycol ether" is referred to as EPEG; "2-acrylamide-2-methylpropane sulfonic acid" is referred to as AMPS, which can be used as an unsaturated sulfonate and also as a chain transfer agent;

The specific parameters or some commonly used reagents or raw materials in the above embodiments are specific embodiments or preferred embodiments of the present invention, but are not intended to limit the present invention. Those skilled in the art may make adaptive adjustments within the scope of the present invention.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims (10)

An EPEG type polycarboxylic acid water reducer, characterized in that: it is polymerized from comonomers, wherein the comonomers include ethylene glycol monovinyl polyethylene glycol ether, unsaturated amide monomers, unsaturated carboxylic acid monomers, unsaturated sulfonates, silane monomers, chloroallyl dimethyl phosphate and quaternary ammonium salt polyether ester monomers; The weight ratio of the ethylene glycol monovinyl polyethylene glycol ether, the unsaturated amide monomer, the unsaturated carboxylic acid monomer, the unsaturated sulfonate, the silane monomer, the dimethyl chloride allyl phosphate and the quaternary ammonium salt polyether ester monomer is (200-300): (4-8): (20-30): (4-8): (2-4): (4-6): (4-6). The EPEG type polycarboxylic acid water reducer according to claim 1 is characterized in that it is prepared by copolymerizing ethylene glycol monovinyl polyethylene glycol ether, unsaturated amide monomer, unsaturated carboxylic acid monomer, unsaturated sulfonate, silane monomer, dimethyl chloride allyl phosphate and quaternary ammonium salt polyether ester monomer at 10°C to 15°C. The EPEG type polycarboxylic acid water reducer according to claim 1, characterized in that: the unsaturated amide monomer is one or more combinations of acrylamide, N-(2-dimethylaminoethyl)acrylamide, N,N-methylenebisacrylamide, cyclopropaneamide, and caprolactam; The unsaturated carboxylic acid monomer is one or more combinations of acrylic acid, methacrylic acid, fumaric acid, maleic anhydride, and itaconic acid; The unsaturated sulfonate is one or more combinations of sodium methyl propylene sulfonate, sodium styrene sulfonate, 2-acrylamide-2-methylpropane sulfonic acid, and sodium dodecylbenzene sulfonate; The silane monomer is one or more combinations of vinyl trimethoxy silane, vinyl triethoxy silane, γ-methacryloxypropyl trimethoxy silane, KH550, and KH570; The quaternary ammonium salt polyether ester monomer is a blocked quaternary ammonium salt diethylene glycol monoallyl ether carboxylate. The EPEG type polycarboxylate water reducer according to claim 1, characterized in that: the chlorinated allyl dimethyl phosphate is prepared by esterification reaction of allyl dimethyl phosphate and thionyl chloride; The weight ratio of the allyl dimethyl phosphate to the thionyl chloride is 100:(100-150). The EPEG type polycarboxylate water reducer according to claim 4 is characterized in that: the preparation method of the chloroallyl dimethyl phosphate is: Allyl dimethyl phosphate and solvent A are mixed, and a first catalyst and a polymerization inhibitor are added, the reaction system is heated to 40° C. to 60° C., and thionyl chloride is added to the reaction system, and an esterification reaction is carried out at 40° C. to 60° C. for 2 to 4 hours and the temperature is kept for 3 to 5 hours to obtain the chloroallyl dimethyl phosphate; wherein the preparation of the chloroallyl dimethyl phosphate is carried out under a nitrogen atmosphere or an inert atmosphere throughout the reaction; The weight ratio of allyl dimethyl phosphate, solvent A, thionyl chloride, the first catalyst and the polymerization inhibitor is 100: (350-400): (100-150): (5-10): (0.5-1.0). The EPEG type polycarboxylate water reducer according to claim 5, characterized in that: the solvent A is one or more combinations of dichloromethane, chloroform, acetonitrile, and toluene; The first catalyst is one or more combinations of N'N dimethylformamide, pyridine, 4-dimethylaminopyridine, concentrated sulfuric acid, and ethylsulfonic acid; The polymerization inhibitor is one or more combinations of hydroquinone, p-hydroxyanisole, phenothiazine, cuprous chloride and ferric chloride. The EPEG type polycarboxylate water reducer according to claim 1, characterized in that: the preparation method of the quaternary ammonium salt polyether ester monomer is: Add diethylene glycol monoallyl ether, amino acid and the second catalyst into a reaction kettle and mix them evenly, react at 60°C to 120°C for 2 to 8 hours and then cool to room temperature, then add chloroform into the reaction kettle, mix evenly and let stand for 12 to 24 hours to obtain diethylene glycol monoallyl ether carboxylate; The obtained diethylene glycol monoallyl ether carboxylate is added into unsaturated acid anhydride and solvent A to dissolve, and then pyridine is added to react to obtain carboxyl-terminated diethylene glycol monoallyl ether carboxylate; The obtained terminal carboxyl diethylene glycol monoallyl ether carboxylate is dissolved in N'N-dimethylformamide, thionyl chloride is added under a nitrogen atmosphere or an inert atmosphere, and the reaction system is heated to 40°C to 60°C for 5h to 12h to obtain acyl chloride diethylene glycol monoallyl ether carboxylate; The obtained acyl chloride diethylene glycol monoallyl ether carboxylate is added to ethanolamine, N'N-dimethylformamide and a mixture of quaternary ammonium salt compounds, and the mixture is reacted at 65° C. to 90° C. for 5 to 24 hours to obtain a quaternary ammonium salt polyether ester monomer. The EPEG type polycarboxylate water reducer according to claim 7, characterized in that: the amino acid is one or more combinations of glutamic acid and aspartic acid; The solvent A is one or more of dichloromethane, chloroform, acetonitrile and toluene; The second catalyst is one or more combinations of thionyl chloride, copper sulfate, and tetrabutyl titanate; The unsaturated anhydride is one or more combinations of maleic anhydride and succinic anhydride; The quaternary ammonium salt compound is one or more combinations of ammonium chloride, methacryloyloxyethyl trimethyl ammonium chloride, dimethyl alkyl ammonium chloride, benzyl trimethyl ammonium chloride and chlormequat chloride. A method for preparing the EPEG type polycarboxylate water reducer according to any one of claims 1 to 8, characterized in that it comprises the following steps: Dissolving ethylene glycol monovinyl polyethylene glycol ether in water; adding unsaturated amide monomer, sulfate, silane monomer, dimethyl chloroallyl phosphate and oxidant to the aqueous solution of ethylene glycol monovinyl polyethylene glycol ether to prepare a base solution, and controlling the temperature of the reaction system to be 10° C. to 15° C.; Unsaturated carboxylic acid monomer, quaternary ammonium salt polyether ester monomer, unsaturated sulfonate, chain transfer agent and reducing agent are added to the base liquid, and copolymerization reaction is carried out at 10° C. to 15° C. to prepare the EPEG type polycarboxylate water reducer. A quaternary ammonium salt polyether ester monomer, characterized in that its preparation method is as follows: Add diethylene glycol monoallyl ether, amino acid and the second catalyst into a reaction kettle and mix them evenly, react at 60°C to 120°C for 2 to 8 hours and then cool to room temperature, then add chloroform into the reaction kettle, mix evenly and let stand for 12 to 24 hours to obtain diethylene glycol monoallyl ether carboxylate; The obtained diethylene glycol monoallyl ether carboxylate is added into unsaturated acid anhydride and solvent A to dissolve, and then pyridine is added to react to obtain carboxyl-terminated diethylene glycol monoallyl ether carboxylate; The obtained terminal carboxyl diethylene glycol monoallyl ether carboxylate is dissolved in N'N-dimethylformamide, thionyl chloride is added under a nitrogen atmosphere or an inert atmosphere, and the reaction system is heated to 40°C to 60°C for 5h to 12h to obtain acyl chloride diethylene glycol monoallyl ether carboxylate; Add the obtained diethylene glycol chloride to the mixture of ethanolamine, N'N-dimethylformamide and quaternary ammonium salt compound. Alcohol monoallyl ether carboxylate is reacted at 65°C to 90°C for 5 to 24 hours to obtain a quaternary ammonium salt polyether ester monomer.