A polycarboxylic acid slump retention mother liquor and its preparation method

Abstract

The present invention belongs to the technical field of concrete admixtures, and provides a polycarboxylic acid slump retention mother liquor and a preparation method thereof. The mother liquor is prepared from a variety of components, including a bottom material and a liquid A. Among them, the bottom material includes a polyether macromonomer and a first pH regulator. The polyether macromonomer is vinyl ethylene glycol polyoxyethylene ether, and the first pH regulator is selected from acidic compounds; the liquid A includes acrylic acid, a polyether small monomer and a carboxylic acid ester monomer. The polyether small monomer is an aqueous solution of polyoxyethylene methacrylate, and the average molecular weight is 570-630. The polycarboxylic acid slump retention mother liquor of the present invention has a wider adaptability and better slump retention effect; different side chains are introduced into the side chain of the slump retention mother liquor, and effective groups carboxyl groups of the water reducer are generated by hydrolysis in the alkaline environment of the concrete, ensuring the continuous release ability of the product.

Description

Technical Field

[0001] The present application relates to the technical field of concrete admixtures, and in particular to a polycarboxylic acid collapse-preserving mother solution and a preparation method thereof. Background Art

[0002] Slump loss is a major issue in modern concrete construction. To address this issue, researchers have developed a number of admixtures that effectively suppress slump loss. Among these, slump-preventing agents primarily function to maintain the fluidity of the concrete mix for an extended period, meeting the demands of modern concrete construction.

[0003] At present, in order to ensure that concrete can have good fluidity for a long time, existing technologies have improved the collapse-preventing agents. For example, the amount of retarding materials is increased during the preparation process to solve problems such as collapse over time. However, this method has a slightly low cost-effectiveness and has hidden dangers such as excessively long setting time.

[0004] For example, methyl allyl polyoxyethylene ether (HPEG-2400) or isopentanol polyoxyethylene ether (TPEG2400) is polymerized with acrylic acid, hydroxyethyl acrylate, etc. to prepare a slow-release polycarboxylic acid mother liquor, but problems such as water exudation after 1 to 1.5 hours and rapid loss after 2 hours are prone to occur.

[0005] Based on this, research and development are underway on high-flowability slump-reducing agents. For example, patent publication number CN105399363B discloses a high-flowability concrete admixture and its preparation method. The admixture is prepared by mixing a high-water-reducing polycarboxylate superplasticizer mother liquor, a slow-release polycarboxylate superplasticizer mother liquor, a thickener, a retarder, and water. The raw materials for the high-water-reducing polycarboxylate superplasticizer mother liquor include HPEG or TPEG; the raw materials for the slow-release polycarboxylate superplasticizer mother liquor include polyoxyethylene methacrylate. This method overcomes the problems of existing admixtures, such as segregation and bleeding, and rapid loss of performance when mixing high-flowability concrete.

[0006] However, the above method requires the preparation of two separate reaction systems: a high-water-reducing polycarboxylate superplasticizer mother liquor and a slow-release polycarboxylate superplasticizer mother liquor. Furthermore, the mixing ratio of the two reaction systems must be controlled. Furthermore, the mixing ratio of the two components in the slow-release polycarboxylate superplasticizer mother liquor must be controlled. This method results in a complex preparation process and a long reaction cycle for the reaction system. Summary of the Invention

[0007] In view of the shortcomings of the existing technology, the present invention provides a polycarboxylic acid collapse-preventing mother solution and a preparation method thereof to solve the problems of the existing collapse-preventing agent having a long setting time, single hydroxyethyl acrylate bleeding over time, and rapid loss of working performance in the later stage.

[0008] To achieve the above-mentioned and related purposes, the present invention adopts the following technical solutions:

[0009] In the first aspect of the present invention, a polycarboxylic acid slump retention mother liquor is provided, which is prepared from a variety of components. The variety of components include a base material and liquid A, where:

[0010] The base material includes a polyether macromonomer and a first pH regulator. The polyether macromonomer is vinyl ethylene glycol polyoxyethylene ether, and the first pH regulator is selected from acidic compounds;

[0011] Liquid A includes acrylic acid, a polyether small monomer, and a carboxylic acid ester monomer. The polyether small monomer is an aqueous solution of polyoxyethylene methacrylate, and the average molecular weight is 570 - 630.

[0012] Furthermore, the variety of components further include liquid B and a first chain transfer agent. Liquid B includes a second chain transfer agent. When formulating, the first chain transfer agent is first added to the base material, and then liquid B is added.

[0013] Furthermore, the mass ratio of the first pH regulator to the polyether macromonomer is (0.3 - 0.8):100.

[0014] Furthermore, the first chain transfer agent is sodium hypophosphite, and the second chain transfer agent is a mercapto chain transfer agent.

[0015] Furthermore, the molar ratio of the polyether macromonomer, acrylic acid, the polyether small monomer, and the carboxylic acid ester monomer is 1:(1 - 2.5):(0.2 - 1):(2 - 5).

[0016] Furthermore, the carboxylic acid ester monomer is selected from one or more of methyl acrylate, hydroxyethyl acrylate, and hydroxypropyl acrylate.

[0017] Furthermore, liquid B further includes a reducing agent and a second pH regulator. The second pH regulator is selected from basic compounds.

[0018] Furthermore, the variety of components further include an aqueous solution of ferrous sulfate and an oxidizing agent.

[0019] In the second aspect of the present invention, a preparation method of a polycarboxylic acid slump retention mother liquor is provided, including the following steps:

[0020] (1) Prepare the base material: Mix water, the polyether macromonomer, and the first pH regulator to obtain the base material, where the polyether macromonomer is vinyl ethylene glycol polyoxyethylene ether, and the first pH regulator is an acidic compound;

[0021] (2) Prepare liquid A: Mix water, acrylic acid, the polyether small monomer, and the carboxylic acid ester monomer to obtain liquid A, where the polyether small monomer is an aqueous solution of polyoxyethylene methacrylate, and the average molecular weight is 570 - 630;

[0022] (3) Prepare liquid B: Mix water, the second pH regulator, the reducing agent, and the second chain transfer agent to obtain liquid B;

[0023] (4) Add a first chain transfer agent, an aqueous solution of ferrous sulfate, and an oxidizing agent to the base material in sequence, stir, dropwise add Liquid B and Liquid A for reaction, keep warm, and add water for dilution to obtain a polycarboxylic acid slump retaining mother liquor.

[0024] Furthermore, in step (4), the reaction temperature is 10°C to 30°C.

[0025] The beneficial technical effects of the present invention are as follows:

[0026] The present invention uses a polyether macromonomer, acrylic acid, a polyether small monomer, and a carboxylic acid ester monomer to form a new redox system, and its free radical polymerization effect is better; uses a polyether small monomer (aqueous solution of polyoxyethylene ether methacrylate) for side chain graft modification, introducing a polyether small monomer into the side chain to improve the alkaline hydrolysis rate of esters, so as to solve the deficiencies such as bleeding over time and rapid loss of working performance in the later stage of a single hydroxyethyl acrylate.

[0027] The present invention selects an acidic compound as the first pH regulator to adjust the reaction pH, so as to increase the monomer dissolution rate, thereby shortening the reaction cycle, reducing the initial reaction rate, and increasing the proportion of effective polymers.

[0028] In the preparation process of the polycarboxylic acid slump retaining mother liquor of the present invention, the chain transfer agent adopts a combined mode of adding sodium hypophosphite to the base material at one time and dropwise adding a mercapto-based chain transfer agent, so as to better control the molecular weight of the polymer, thereby improving the water retention performance and slump retention ability of the slump retaining mother liquor.

[0029] The polycarboxylic acid slump retaining mother liquor of the present invention has a wider adaptability and better slump retaining effect; different branched chains are introduced into the side chain of the slump retaining mother liquor, and effective groups carboxyl groups of water reducing agents are hydrolyzed in the alkaline environment of concrete to ensure the continuous release ability of the product.

[0030] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this application. Detailed embodiments

[0031] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It should be understood that certain features of the present invention, which are described in the context of separate embodiments for clarity, may also be provided in combination in a single embodiment. Conversely, the multiple features of the present invention, which are described in the context of a single embodiment for brevity, may also be provided separately or in any suitable combination or, when appropriate, in any other described embodiment of the present invention. Certain features described in the context of various embodiments will not be considered essential features of those embodiments unless the embodiment is inoperable without those elements. The present invention is further illustrated below by specific specific examples, but it should be noted that the specific process conditions and results described in the embodiments of the present invention are only used to illustrate the present invention and cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

[0032] The present invention provides a polycarboxylate slump-retention mother liquor, which is prepared from a variety of components. The variety of components include a base material and liquid A, wherein:

[0033] The base material includes a polyether macromonomer and a first pH regulator. The polyether macromonomer is vinyl ethylene glycol polyoxyethylene ether, and the first pH regulator is selected from acidic compounds;

[0034] Liquid A includes acrylic acid, a polyether small monomer, and a carboxylic acid ester monomer. The polyether small monomer is an aqueous solution of polyoxyethylene ether methacrylate, and the average molecular weight is 570 - 630.

[0035] In some embodiments, the polyether macromonomer of the present application is preferably polyoxyethylene ether GPEG3000 produced by Jiangsu Sierbang. As a part of the side chain, polyoxyethylene ether GPEG3000 participates in the synthesis of the polycarboxylate slump-retention mother liquor. This side chain structure endows the polycarboxylate slump-retention mother liquor with characteristics such as low dosage, high water reduction rate, high dispersibility, high slump retention, and a designable molecular structure.

[0036] In some embodiments, the added polyether small monomer of the present application is an 80% aqueous solution of polyoxyethylene ether methacrylate, which is PC-106. The functions of the small monomer polyoxyethylene ether methacrylate in the slump-retention mother liquor include: improving the slump retention performance of concrete, extending the workable time of concrete, and preventing concrete from shrinking and cracking. There is almost no use of low-molecular-weight polyoxyethylene ether methacrylate in the existing slump-retention mother liquor. The present application selects low-molecular-weight polyoxyethylene ether methacrylate as the polyether small monomer. As a side chain branch, it improves the alkaline hydrolysis rate of esters, helps maintain the dispersibility of cement, solves the problems of bleeding over time and late loss of a single hydroxyethyl acrylate, and further enhances the slump retention performance of the slump-retention mother liquor.

[0037] In some embodiments, the carboxylic acid ester monomer is selected from one or more of methyl acrylate, 2-hydroxyethyl acrylate, and 2-hydroxypropyl acrylate.

[0038] In some embodiments, the molar ratio of the polyether macromonomer, acrylic acid, polyether small monomer, and carboxylic acid ester monomer is 1:(1 - 2.5):(0.2 - 1):(2 - 5). In this application, by controlling the molar ratio of each monomer component in the base material and liquid A, the acid-ether ratio in the slump retention mother liquor is regulated, so that the prepared slump retention mother liquor can provide better initial working performance and smaller time-dependent loss, and improve the dispersion performance and water retention performance of the slump retention mother liquor.

[0039] In some embodiments, the first pH regulator of this application is preferably acetic acid. The reaction pH value is adjusted with acetic acid to increase the monomer dissolution rate, thereby shortening the reaction cycle and reducing the initial reaction rate, and increasing the proportion of effective polymer.

[0040] In some embodiments, the mass ratio of the first pH regulator to the polyether macromonomer is (0.3 - 0.8):100.

[0041] In some embodiments, the multiple components further include liquid B and a first chain transfer agent. Liquid B includes a second chain transfer agent. When formulating, the first chain transfer agent is first added to the base material, and then liquid B is added.

[0042] In some embodiments, the first chain transfer agent is sodium hypophosphite, and the second chain transfer agent is a mercapto chain transfer agent. The mercapto chain transfer agent of this application is selected from mercaptopropionic acid and / or mercaptoethanol.

[0043] In some embodiments, this application uses the polyether macromonomer, acrylic acid, polyether small monomer, and carboxylic acid ester monomer as the reaction units of the free radical polymerization reaction. The mass ratio of sodium hypophosphite to the reaction unit is (0.5 - 2):100.

[0044] In some embodiments, the mass ratio of the mercapto chain transfer agent to the reaction unit is (0.2 - 0.8):100.

[0045] In some embodiments, liquid B further includes a reducing agent and a second pH regulator. The second pH regulator is selected from basic compounds. The second pH regulator of this application is preferably sodium hydroxide. The reducing agent of this application is selected from one or several of L-ascorbic acid, sodium formaldehyde sulfoxylate, and imported E51.

[0046] In some embodiments, the multiple components further include an oxidizing agent. The oxidizing agent of this application is selected from hydrogen peroxide and / or sodium persulfate.

[0047] In some embodiments, the mass ratio of the reducing agent to the reaction unit is (0.1 - 0.4):100.

[0048] In some embodiments, the mass ratio of the oxidant to the polyether macromonomer is (0.5 - 1):100.

[0049] The present invention also provides a method for preparing a polycarboxylic acid slump retaining mother liquor, comprising the following steps:

[0050] (1) Prepare the base material: Mix water, a polyether macromonomer, and a first pH regulator to obtain the base material, wherein the polyether macromonomer is vinyl ethylene glycol ether polyoxyethylene ether, and the first pH regulator is an acidic compound;

[0051] (2) Prepare solution A: Mix water, acrylic acid, a polyether small monomer, and a carboxylic acid ester monomer to obtain solution A, wherein the polyether small monomer is an aqueous solution of polyoxyethylene methacrylate, and the average molecular weight is 570 - 630;

[0052] (3) Prepare solution B: Mix water, a second pH regulator, a reducing agent, and a second chain transfer agent to obtain solution B;

[0053] (4) Add a first chain transfer agent, an aqueous solution of ferrous sulfate, and an oxidant to the base material in sequence, stir for 5 min, and uniformly dropwise add solution B and solution A for reaction, keep warm for 30 min - 60 min, and add water to dilute to a concentration of 40% to obtain the polycarboxylic acid slump retaining mother liquor.

[0054] In some embodiments, the chain transfer agent of the present application adopts a combined mode of adding sodium hypophosphite to the base material at one time and dropwise adding a mercapto-based chain transfer agent to better control the molecular weight of the polymer, thereby improving the water retention performance and slump retention ability of the slump retaining mother liquor.

[0055] In some embodiments, the water of the present application is preferably deionized water.

[0056] In some embodiments, the mass concentration of the aqueous solution of ferrous sulfate is 1%.

[0057] In some embodiments, the mass ratio of the 1% aqueous solution of ferrous sulfate to the polyether macromonomer is (0.05 - 0.5):100.

[0058] In some embodiments, the dropping time of solution B is 60 min - 80 min.

[0059] In some embodiments, the dropping time of solution A is 50 min - 60 min.

[0060] In some embodiments, the temperature of the reaction system before dropping is maintained at 10°C - 20°C, and the reaction temperature after dropping is 10°C - 30°C to control the reaction rate of the chemical reaction, avoid unnecessary side reactions, avoid affecting the molecular structure and molecular weight distribution of the slump retaining mother liquor, and improve the performance and stability of the slump retaining mother liquor.

[0061] The present invention will be described in detail below through specific exemplary embodiments. It should be understood that the following embodiments are only used to specifically illustrate the present invention and should not be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention all fall within the protection scope of the present invention. The specific process parameters and the like in the following examples are also only an example within a suitable range, that is, those skilled in the art can make selections within a suitable range through the description herein, rather than being limited to the specific values in the following examples.

[0062] Example 1

[0063] (1) Prepare the base material: Add 3100 parts of deionized water to a reaction kettle equipped with a thermometer, a stirrer, a double dropping pipe, and a reflux condenser. Start stirring, add 3100 parts of polyoxyethylene ether GPEG3000 produced by Jiangsu Silbon, and add 15 parts of acetic acid, and mix and dissolve to obtain the base material;

[0064] (2) Prepare Solution A: Mix 459 parts of deionized water, 108 parts of acrylic acid, 360 parts of polyether monomer PC-106, 50 parts of methyl acrylate, and 406 parts of 2-hydroxyethyl acrylate to obtain Solution A;

[0065] (3) Prepare Solution B: Mix 1000 parts of deionized water, 3 parts of solid sodium hydroxide, 8 parts of mercaptopropionic acid, 8 parts of mercaptoethanol, and 11 parts of Rongalite to obtain Solution B;

[0066] (4) After the solids in the base material are dissolved and the temperature in the reaction kettle is 10°C to 15°C, add 20 parts of sodium hypophosphite, 5 parts of 1% aqueous solution of ferrous sulfate, and 25 parts of 27.5% hydrogen peroxide in sequence. After stirring for 5 minutes, start to uniformly drop Solution B for 60 minutes to 75 minutes and Solution A for 55 minutes to 60 minutes. After dropping, keep warm for 45 minutes to 60 minutes, and add 1290 parts of deionized water and mix evenly to obtain a polycarboxylic acid slump retaining mother liquor.

[0067] It should be noted that if the temperature exceeds 25°C during the reaction, cooling water needs to be turned on to cool down to ensure that the reaction temperature is below 30°C.

[0068] Example 2

[0069] The difference between this example and Example 1 is as follows:

[0070] (1) Prepare the base material: Add 3100 parts of deionized water to a reaction kettle equipped with a thermometer, a stirrer, a double dropping pipe, and a reflux condenser. Start stirring, add 3100 parts of polyoxyethylene ether GPEG3000 produced by Jiangsu Silbon, and add 22 parts of acetic acid, and mix and dissolve to obtain the base material.

[0071] Example 3

[0072] The difference between this embodiment and Embodiment 1 is as follows:

[0073] (3) Prepare Solution B: Mix 1100 parts of deionized water, 3 parts of solid sodium hydroxide, 15 parts of mercaptopropionic acid, 15 parts of mercaptoethanol, and 11 parts of Rongalite to obtain Solution B.

[0074] Embodiment 4

[0075] The difference between this embodiment and Embodiment 1 is as follows:

[0076] (4) After the solids in the bottom material are dissolved and the temperature in the reaction kettle is 10°C to 15°C, add 70 parts of sodium hypophosphite, 5 parts of 1% ferrous sulfate aqueous solution, and 25 parts of 27.5% hydrogen peroxide in sequence. After stirring for 5 minutes, start to uniformly add Solution B dropwise for 60 minutes to 75 minutes and Solution A dropwise for 55 minutes to 60 minutes. After dropping, keep warm for 45 minutes to 60 minutes, and add 1320 parts of deionized water and mix evenly to obtain the polycarboxylic acid slump retention mother liquor.

[0077] Comparative Example 1

[0078] The difference between this comparative example and Embodiment 1 is as follows:

[0079] (1) Prepare the bottom material: Add 3100 parts of deionized water to a reaction kettle equipped with a thermometer, a stirrer, a double dropping pipe, and a reflux condenser. Start stirring, add 3100 parts of polyoxyethylene ether GPEG3000, and add 15 parts of acetic acid, and mix and dissolve to obtain the bottom material;

[0080] (2) Prepare Solution A: Mix 459 parts of deionized water, 108 parts of acrylic acid, 50 parts of hydroxypropyl acrylate, and 406 parts of hydroxyethyl acrylate to obtain Solution A.

[0081] Comparative Example 2

[0082] The difference between this comparative example and Embodiment 1 is as follows:

[0083] (1) Prepare the bottom material: Add 3100 parts of deionized water to a reaction kettle equipped with a thermometer, a stirrer, a double dropping pipe, and a reflux condenser. Start stirring, add 3100 parts of TPEG2400, and add 15 parts of acetic acid, and mix and dissolve to obtain the bottom material;

[0084] (2) Prepare Solution A: Mix 459 parts of deionized water, 108 parts of acrylic acid, and 406 parts of hydroxyethyl acrylate to obtain Solution A.

[0085] Comparative Example 3

[0086] The difference between this comparative example and Embodiment 1 is as follows:

[0087] The average molecular weight of the polyether monomer polyoxyethylene methacrylate is 1924.

[0088] Comparative Example 4

[0089] The difference between this comparative example and Example 1 is that:

[0090] The base material does not contain acetic acid.

[0091] Comparative Example 5

[0092] The difference between this comparative example and Example 1 is that:

[0093] Sodium hypophosphite is not added in step (4).

[0094] Performance detection

[0095] Performance of the slump retaining mother liquor: Detect the performance of the slump retaining mother liquor in Example 1 and Comparative Examples 1-5, and the test results are shown in Table 1.

[0096] The test method is as follows: The fluidity of cement paste is tested with reference to the national standard GB / T8077-2012 "Test Methods for the Homogeneity of Concrete Admixtures". In each test sample, the dosage of the polycarboxylate slump retaining mother liquor in Example 1 and Comparative Examples 1-5 is 0.15% of the total mass of the binder, and W / C is 0.29. The test results are shown in Table 1.

[0097] The concrete test is carried out with reference to the national standard GB 8076-2008 "Concrete Admixtures". Among them, the cement is Conch P·O 42.5, the sand is a mixture of fine sand with a fineness modulus of 1.8, manufactured sand with a fineness modulus of 3.2 and medium sand with a fineness modulus of 2.3, and the average fineness modulus is 2.7. The gravel is continuously graded from 5mm to 31.5mm. The admixture is prepared by mixing Example 1 and Comparative Examples 1-5 with 6 50% solid contents and ordinary water-reducing polycarboxylate in a mass ratio of 5:5, and the dosage is 0.18% (in terms of solid) of the total mass of the cementitious material. The test is carried out according to the following mass ratio: cement: fly ash: sand: gravel: water: admixture = 280:50:800:1080:150:0.594 (in terms of solid) (unit: kg / m 3 ), and the test results are shown in Table 1.

[0098] The experimental data and analysis are as follows:

[0099] Table 1 Performance of the slump retaining mother liquor in Example 1 and Comparative Examples 1-5

[0100]

[0101]

[0102] As can be seen from Table 1, the fluidity of the cement paste of the polycarboxylate slump-retention mother liquor prepared in Example 1 of the present application first increases and then remains stable within the 3-hour period. The slump-retention effect is obvious, with a good slow-release effect, which can reduce the time-dependent loss of concrete.

[0103] The polycarboxylate slump-retention mother liquor prepared in Example 1 of the present application can maintain the slump and spread of concrete for a long time. It can reduce bleeding and segregation and reduce slump loss.

[0104] In Comparative Example 1 and Comparative Example 2, the polyether small monomer PC-106 of the present application is not contained, and the fluidity retention effect of the cement paste is poor, which has a negative impact on the workability of concrete, resulting in insufficient fluidity during the construction process, large slump loss of concrete, and slightly bleeding phenomenon.

[0105] In Comparative Example 3, the molecular weight of the polyether small monomer is too high, and the side chain in the slump-retention mother liquor is too large, which affects the alkaline hydrolysis rate of esters and reduces the fluidity of the cement paste and the slump loss of concrete is large.

[0106] In Comparative Example 4, acetic acid is not contained in the base material, and the proportion of the effective polymer is low, which affects the effective dispersion and stabilization of the polymer on the cement particles, resulting in a decrease in the fluidity of the cement paste, an accelerated slump loss of concrete, and bleeding phenomenon.

[0107] In Comparative Example 5, the combination mode of adding sodium hypophosphite to the base material at one time and dropping mercapto chain transfer agent is not used as the chain transfer agent, resulting in too large molecular weight of the polymer, which affects the slump retention ability of concrete and accelerates the slump loss. Although the initial fluidity of the cement paste in Comparative Example 5 is good, after a period of time, the fluidity retention ability of the cement paste decreases significantly, and the effect of the slump-retention mother liquor is poor.

[0108] The above embodiments merely illustrate the principles and effects of the present invention, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A polycarboxylic acid slump retention mother liquor is prepared from multiple components. The multiple components include a base material and Liquid A. It is characterized in that: The base material includes a polyether macromonomer and a first pH regulator. The polyether macromonomer is ethylene glycol vinyl ether polyoxyethylene ether, and the first pH regulator is selected from acetic acid; Liquid A includes acrylic acid, a polyether small monomer, and a carboxylic acid ester monomer. The polyether small monomer is an aqueous solution of methacrylic acid polyoxyethylene ether, and the average molecular weight is 570 - 630. The carboxylic acid ester monomer is selected from one or more of methyl acrylate, hydroxyethyl acrylate, and hydroxypropyl acrylate; The multiple components further include Liquid B and a first chain transfer agent. Liquid B includes a second chain transfer agent. When preparing, the first chain transfer agent is first added to the base material, and then Liquid B is added; the first chain transfer agent is sodium hypophosphite, and the second chain transfer agent is a mercapto - type chain transfer agent.

2. The polycarboxylate slump retaining mother liquor according to claim 1, characterized in that, The mass ratio of the first pH regulator to the polyether macromonomer is (0.3 - 0.8):

100.

3. The polycarboxylic acid slump retaining mother liquor according to claim 1, characterized in that, The molar ratio of the polyether macromonomer, acrylic acid, the polyether small monomer, and the carboxylic acid ester monomer is 1:(1 - 2.5):(0.2 - 1):(2 - 5).

4. The polycarboxylic acid slump retention mother liquor according to claim 1, wherein Liquid B further includes a reducing agent and a second pH regulator. The second pH regulator is selected from basic compounds.

5. The polycarboxylic acid slump retaining mother liquor according to claim 1, wherein The multiple components further include an aqueous solution of ferrous sulfate and an oxidizing agent.

6. A preparation method of a polycarboxylic acid slump retaining mother liquor, characterized in that, It includes the following steps: (1) Prepare the base material: Mix water, the polyether macromonomer, and the first pH regulator to obtain the base material, where the polyether macromonomer is ethylene glycol vinyl ether polyoxyethylene ether, and the first pH regulator is acetic acid; (2) Prepare Liquid A: Mix water, acrylic acid, the polyether small monomer, and the carboxylic acid ester monomer to obtain Liquid A, where the polyether small monomer is an aqueous solution of methacrylic acid polyoxyethylene ether, and the average molecular weight is 570 - 630. The carboxylic acid ester monomer is selected from one or more of methyl acrylate, hydroxyethyl acrylate, and hydroxypropyl acrylate; (3) Prepare Liquid B: Mix water, the second pH regulator, the reducing agent, and the second chain transfer agent to obtain Liquid B; the second chain transfer agent is a mercapto - type chain transfer agent; (4) Add the first chain transfer agent, the aqueous solution of ferrous sulfate, and the oxidizing agent to the base material in sequence, stir, dropwise add Liquid B and Liquid A for reaction, keep warm, and add water for dilution to obtain the polycarboxylic acid slump retention mother liquor; the first chain transfer agent is sodium hypophosphite.

7. The preparation method according to claim 6, characterized in that, The reaction temperature in step (4) is 10°C - 30°C.

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