Mud-resistant early-strength polycarboxylate superplasticizer and preparation method thereof

Abstract

The invention relates to a mud-resistant early-strength polycarboxylic acid water reducing agent and a preparation method thereof, and the mud-resistant early-strength polycarboxylic acid water reducing agent is prepared from the following raw materials in parts by mass: 180 parts of ethylene glycol monovinyl polyoxyethylene ether; 10 to 15 parts of an unsaturated acid monomer; 3-5 parts of a temperature-sensitive monomer; 5 to 10 parts of unsaturated ester functional monomer; and 1-5 parts of an unsaturated phosphate monomer. Starting from molecular structure design, through the synergistic effect of multiple functional monomers, the improvement of multiple properties such as early strength, mud resistance and temperature-sensitive response of concrete is realized.

Description

Technical Field

[0001] This invention relates to the field of concrete admixture technology, specifically to an anti-mud early-strength polycarboxylate superplasticizer and its preparation method. Background Technology

[0002] With the development of modern construction engineering towards high-rise buildings, prefabrication, and rapid construction, the early strength development rate of concrete has become a key factor affecting project progress and energy efficiency. In applications such as low-temperature construction, rapid formwork removal, and prestressing, traditional polycarboxylate superplasticizers (PCEs), due to their adsorption-dispersion behavior on cement particles primarily characterized by delayed hydration, cannot meet the demand for rapid strength development within 1–3 days. Studies have shown that shortening the curing time of precast components by 24 hours can significantly reduce energy consumption by more than 15% (Zhang et al., 2021). However, the design philosophy of traditional PCE materials focuses on high water reduction rates and workability, creating an inherent contradiction between their hydration-inhibiting nature and the requirement for early strength.

[0003] Furthermore, the presence of clay powder (mainly highly adsorbent clay minerals) in manufactured sand further exacerbates the deterioration of concrete performance. Clay minerals possess a large specific surface area and cation exchange capacity (CEC). Their layered structure carries a positive charge at its edges, strongly adsorbing the negatively charged PCE molecular backbone, resulting in the "ineffective" consumption of a large amount of water-reducing agent. This phenomenon leads to the following problems: poor concrete adaptability, reduced initial water reduction rate, and accelerated slump loss. To restore workability, on-site construction often involves adding water to increase fluidity, leading to an increased water-cement ratio and a significant decrease in concrete density and strength.

[0004] In recent years, researchers have attempted to enhance the adsorption capacity of PCE (polycarbonate) by introducing functional monomers such as sulfonic acid groups and amino groups to improve early strength. However, these strategies have significant limitations: the increase in early strength is generally less than 10%, and it is often accompanied by a decline in later strength or durability. Existing technologies such as electrostatic repulsion-enhanced, nucleation-induced, and calcium-chelated early-strength PCE, while promoting early hydration to some extent, have failed to systematically resolve the contradiction between insufficient early hydration activity and microstructure deterioration, especially lacking the ability to directionally control the surface reaction process of the main cement mineral phase C3S. Summary of the Invention

[0005] Therefore, it is necessary to provide an anti-mud early-strength polycarboxylate superplasticizer and its preparation method, in order to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides a technical solution:

[0007] A type of anti-mud early-strength polycarboxylate superplasticizer, wherein the raw materials for preparing the anti-mud early-strength polycarboxylate superplasticizer, by weight, include:

[0008]

[0009] Preferably, the temperature-sensitive monomer is poly(N-isopropylacrylamide).

[0010] Preferably, the unsaturated ester functional monomer is obtained by esterification of acrylic acid and polyethylene glycol under the action of p-toluenesulfonic acid catalyst and hydroquinone polymerization inhibitor.

[0011] Preferably, the polyethylene glycol is one of PEG-3000, PEG-4000 or PEG-5000.

[0012] Preferably, the molecular weight of the ethylene glycol monovinyl polyoxyethylene ether is 2000, 2400 or 3000.

[0013] Preferably, the unsaturated phosphate monomer comprises methacryloyloxyethyl phosphate.

[0014] Preferably, the unsaturated acid monomer includes at least one of acrylic acid, methacrylic acid, and itaconic acid.

[0015] Preferably, the raw materials for preparing the anti-mud early-strength polycarboxylate superplasticizer further include, by weight parts:

[0016] 2-4 parts oxidant;

[0017] 0.1-2 parts reducing agent;

[0018] Molecular weight regulator 1-5 parts.

[0019] Preferably, the redox initiation system includes an oxidant and a reducing agent;

[0020] The oxidant includes one of hydrogen peroxide and ammonium persulfate;

[0021] The reducing agent includes at least one of sodium hypophosphite and L-ascorbic acid;

[0022] The molecular weight regulator includes at least one of mercaptoethanol, mercaptopropionic acid, and sulfonated mercaptopropionic acid.

[0023] This invention also provides a method for preparing an anti-mud early-strength polycarboxylate superplasticizer, comprising the following steps:

[0024] (1) Solution preparation: Weigh the unsaturated acid according to the proportion, add caustic soda to neutralize it, adjust the pH value to 6-7, and then add unsaturated ester functional monomer, thermosensitive monomer, unsaturated phosphate ester monomer and water to prepare solution A.

[0025] Weigh the reducing agent, molecular weight regulator and water according to the proportions, and prepare solution B;

[0026] (2) Add ethylene glycol monovinyl polyoxyethylene ether and deionized water to a four-necked flask, stir well, then add oxidant and accelerator, and stir for 10 min.

[0027] (3) Add solution A and solution B slowly dropwise into a four-necked flask. The dropwise addition time for solution A is 60 min and the dropwise addition time for solution B is 70 min. After the addition is complete, keep the temperature constant for 30 min. After the reaction is complete, add triethanolamine and adjust the pH to 5-6 to obtain the anti-mud early strength polycarboxylate superplasticizer.

[0028] The beneficial effects of this invention are:

[0029] This invention introduces a temperature-sensitive monomer into an anti-mud, early-strength polycarboxylate superplasticizer through molecular structure innovation, endowing it with temperature-responsive characteristics and achieving a synergistic improvement in the early strength, anti-mud properties, and temperature-sensitive response of concrete.

[0030] By changing the conformation of temperature-sensitive monomers, the surface reaction of cement particles (especially the C3S phase) is activated in a low-temperature construction environment, breaking through the bottleneck of traditional PCE in inhibiting early hydration, significantly improving the 1-3 day strength, and meeting the requirements of rapid demolding and prestressing tensioning.

[0031] Unsaturated ester functional monomers effectively block the ineffective adsorption of PCE backbone by clay minerals, reduce the consumption of water-reducing agent by mud powder, ensure the workability stability of concrete under manufactured sand conditions, and avoid strength loss due to water addition.

[0032] This invention, through the synergistic regulation of multiple functional monomers, promotes early hydration while maintaining the compactness of the microstructure in the later stages, overcoming the defects of late-stage strength reduction and durability decline in existing early-strength technologies.

[0033] The optimization of early strength performance directly shortens the curing time and reduces the energy consumption of precast component production, which aligns with the technological trends of green building and rapid construction. Detailed Implementation

[0034] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0035] In the embodiments, unless otherwise specified, the experimental methods used are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0036] A type of anti-mud early-strength polycarboxylate superplasticizer, wherein the raw materials for preparing the anti-mud early-strength polycarboxylate superplasticizer, by weight, include:

[0037]

[0038] 1. This invention imparts temperature-responsive properties to the material by introducing the thermosensitive monomer poly(N-isopropylacrylamide) (PNIPAM) into the molecular chain of the polycarboxylate superplasticizer. The PNIPAM chain segments extend after dissolving in water, and their amide groups (-CONH-) can form hydrogen bonds with water molecules, effectively promoting the cement hydration process and significantly improving the early strength of concrete.

[0039] 2. Ethylene glycol monovinyl polyoxyethylene ether (molecular weight 2000-3000) is selected as the main polyether macromonomer. While maintaining the side chain density required for anti-mud properties, the side chain length of PEO is appropriately shortened to reduce its shielding and retarding effects on cement hydration and further promote early strength development.

[0040] 3. By introducing methacryloyloxyethyl phosphate as a functional monomer, which has both anti-mud and strong adsorption capabilities, it can significantly accelerate the early hydration process and shorten the setting time.

[0041] 4. Simultaneously, acrylic acid and high molecular weight polyethylene glycol were esterified under the catalysis of p-toluenesulfonic acid to synthesize esterified macromonomers with both early strength and low sensitivity.

[0042] In summary, this invention, starting from molecular structure design, achieves improvements in multiple properties of concrete, such as early strength, mud resistance, and temperature-sensitive response, through the synergistic effect of multiple functional monomers.

[0043] In some embodiments, the thermosensitive monomer is poly(N-isopropylacrylamide).

[0044] In some embodiments, the esterified functional monomer is an esterified monomer obtained by esterification of acrylic acid and polyethylene glycol.

[0045] In some embodiments, the polyethylene glycol is one of PEG-3000, PEG-4000 or PEG-5000.

[0046] In some embodiments, the ethylene glycol monovinyl polyoxyethylene ether has a molecular weight of 2000, 2400, or 3000.

[0047] In some embodiments, the unsaturated phosphate monomer comprises methacryloyloxyethyl phosphate.

[0048] In some embodiments, the unsaturated acid monomer includes at least one of acrylic acid, methacrylic acid, and itaconic acid.

[0049] In some embodiments, the raw materials for preparing the anti-mud early-strength polycarboxylate superplasticizer, by weight, further include:

[0050] 2-4 parts oxidant;

[0051] 0.1-2 parts reducing agent;

[0052] Molecular weight regulator 1-5 parts.

[0053] In some embodiments, the redox initiation system includes an oxidant and a reducing agent;

[0054] The oxidant includes one of hydrogen peroxide and ammonium persulfate;

[0055] The reducing agent includes at least one of sodium hypophosphite and L-ascorbic acid;

[0056] The molecular weight regulator includes at least one of mercaptoethanol, mercaptopropionic acid, and sulfonated mercaptopropionic acid.

[0057] This invention also provides a method for preparing an anti-mud early-strength polycarboxylate superplasticizer, comprising the following steps:

[0058] Ethylene glycol monovinyl polyoxyethylene ether, unsaturated acid monomers, thermosensitive monomers, unsaturated ester functional monomers, and unsaturated phosphate ester monomers are mixed and reacted to obtain the anti-mud early strength polycarboxylate superplasticizer after the reaction is completed.

[0059] Example 1

[0060] S100. Preparation of unsaturated ester functional monomers.

[0061] Acrylic acid and PEG-3000 were mixed at a molar ratio of 2:1, and 3 wt% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was then subjected to an esterification reaction at 110°C for 5 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-1.

[0062] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0063] By weight, 10 parts of acrylic acid are neutralized with 5 parts of caustic soda flakes, and then 10 parts of TM-1, 5 parts of poly(N-isopropylacrylamide), 1 part of methacryloyloxyethyl phosphate and water are added to prepare solution A.

[0064] Prepare solution B by mixing 1.5 parts sodium hypophosphite, 3 parts mercaptoethanol, and water.

[0065] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (3000) and 150 parts of deionized water to a four-necked flask, stir well, then add 2 parts of hydrogen peroxide and 0.2 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0066] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-1.

[0067] Example 2

[0068] S100. Preparation of unsaturated ester functional monomers.

[0069] Acrylic acid and PEG-4000 were mixed at a molar ratio of 2:1, and 3 wt.% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was then subjected to an esterification reaction at 120°C for 4 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-2.

[0070] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0071] By weight, 15 parts of itaconic acid are neutralized with 4.5 parts of caustic soda, then 13 parts of TM-2, 4 parts of poly(N-isopropylacrylamide), 3 parts of methacryloyloxyethyl phosphate and water are added to prepare solution A; 1 part of L-ascorbic acid, 3 parts of mercaptopropionic acid and water are added to prepare solution B.

[0072] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (2400) and 150 parts of deionized water to a four-necked flask, stir well, then add 3 parts of hydrogen peroxide and 0.1 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0073] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-2.

[0074] Example 3

[0075] S100. Preparation of unsaturated ester functional monomers.

[0076] Acrylic acid and PEG-5000 were mixed at a molar ratio of 2:1, and 3 wt.% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was then subjected to an esterification reaction at 120°C for 5 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-3.

[0077] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0078] By weight, 12 parts of methacrylic acid are neutralized with 5.7 parts of caustic soda flakes, then 15 parts of TM-3, 5 parts of poly(N-isopropylacrylamide), 1 part of methacryloyloxyethyl phosphate and water are added to prepare solution A; 1.5 parts of sodium hypophosphite, 4 parts of sulfonated mercaptopropionic acid and water are added to prepare solution B.

[0079] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (2000) and 150 parts of deionized water to a four-necked flask, stir well, then add 4 parts of ammonium persulfate and 0.1 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0080] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-3.

[0081] Example 4

[0082] S100. Preparation of unsaturated ester functional monomers.

[0083] Acrylic acid and PEG-4000 were mixed at a molar ratio of 2:1, and 3 wt.% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was then subjected to an esterification reaction at 100°C for 4 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-4.

[0084] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0085] By weight, 12 parts of acrylic acid are neutralized with 6.6 parts of caustic soda, then 11 parts of TM-4, 3 parts of poly(N-isopropylacrylamide), 2 parts of methacryloyloxyethyl phosphate and water are added to prepare solution A; 0.2 parts of L-ascorbic acid, 2 parts of mercaptoethanol and water are added to prepare solution B.

[0086] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (3000) and 150 parts of deionized water to a four-necked flask, stir well, then add 4 parts of ammonium persulfate and 0.15 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0087] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-4.

[0088] Comparative Example 1

[0089] S100. Preparation of unsaturated ester functional monomers. Acrylic acid and PEG-3000 were mixed at a molar ratio of 2:1, and 3 wt.% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was subjected to esterification at 110°C for 5 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-1.

[0090] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0091] By weight, 10 parts of acrylic acid are neutralized with 5 parts of caustic soda flakes, then 10 parts of TM-1, 5 parts of poly(N-isopropylacrylamide) and water are added to prepare solution A; 1.5 parts of sodium hypophosphite, 3 parts of mercaptoethanol and water are added to prepare solution B.

[0092] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (3000) and 150 parts of deionized water to a four-necked flask, stir well, then add 2 parts of hydrogen peroxide and 0.2 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0093] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-5.

[0094] Comparative Example 2

[0095] S100. Preparation of unsaturated ester functional monomers. Acrylic acid and PEG-3000 were mixed at a molar ratio of 2:1, and 3 wt.% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was subjected to esterification at 110°C for 5 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-1.

[0096] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0097] By weight, 10 parts of acrylic acid are neutralized with 5 parts of caustic soda, then 10 parts of TM-1, 1 part of methacryloyloxyethyl phosphate and water are added to prepare solution A; 1.5 parts of sodium hypophosphite, 3 parts of mercaptoethanol and water are added to prepare solution B.

[0098] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (3000) and 150 parts of deionized water to a four-necked flask, stir well, then add 2 parts of hydrogen peroxide and 0.2 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0099] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-6.

[0100] Comparative Example 3

[0101] S100. Preparation of unsaturated ester functional monomers. Acrylic acid and PEG-3000 were mixed at a molar ratio of 2:1, and 3 wt.% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was subjected to esterification at 110°C for 5 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-1.

[0102] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0103] By weight, 10 parts of acrylic acid are neutralized with 5 parts of caustic soda flakes, then 10 parts of TM-1, 5 parts of poly(N-isopropylacrylamide), 1 part of methacryloyloxyethyl phosphate and water are added to prepare solution A; 1.5 parts of sodium hypophosphite, 3 parts of mercaptoethanol and water are added to prepare solution B.

[0104] Add 180 parts of isopentenyl polyoxyethylene ether (3000) and 150 parts of deionized water to a four-necked flask, stir well, then add 2 parts of hydrogen peroxide and 0.2 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0105] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-7.

[0106] Comparative Example 4

[0107] S100. Preparation of unsaturated ester functional monomers. Acrylic acid and PEG-1000 were mixed at a molar ratio of 2:1, and 3 wt.% p-toluenesulfonic acid and 2 wt.% hydroquinone were added. The mixture was subjected to esterification at 110°C for 5 h under nitrogen protection to obtain the unsaturated ester functional monomer TM-5.

[0108] S200. Preparation of anti-mud early strength polycarboxylate superplasticizer.

[0109] By weight, 10 parts of acrylic acid are neutralized with 5 parts of caustic soda flakes, then 10 parts of TM-5, 5 parts of poly(N-isopropylacrylamide), 1 part of methacryloyloxyethyl phosphate and water are added to prepare solution A; 1.5 parts of sodium hypophosphite, 3 parts of mercaptoethanol and water are added to prepare solution B.

[0110] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (3000) and 150 parts of deionized water to a four-necked flask, stir well, then add 2 parts of hydrogen peroxide and 0.2 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0111] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-8.

[0112] Comparative Example 5

[0113] Preparation of polycarboxylate superplasticizer:

[0114] By weight, 10 parts of acrylic acid are neutralized with 5 parts of caustic soda flakes, then 5 parts of poly(N-isopropylacrylamide), 1 part of methacryloyloxyethyl phosphate and water are added to prepare solution A.

[0115] Prepare solution B by mixing 1.5 parts sodium hypophosphite, 3 parts mercaptoethanol, and water.

[0116] Add 180 parts of ethylene glycol monovinyl polyoxyethylene ether (3000) and 150 parts of deionized water to a four-necked flask, stir well, then add 2 parts of hydrogen peroxide and 0.2 parts of ferrous ammonium sulfate, and stir for 10 minutes.

[0117] Solution A and solution B were added dropwise to a four-necked flask in sequence. Solution A was added over a period of 60 minutes, and solution B was added over a period of 70 minutes. After the addition was complete, the mixture was kept at a constant temperature for 30 minutes. After the reaction was completed, triethanolamine was added to adjust the pH to 5-6, thus obtaining the anti-mud early strength polycarboxylate superplasticizer KZ-9.

[0118] The anti-mud early-strength polycarboxylate superplasticizers prepared in Examples 1-4 and Comparative Examples 1-5 were tested using Jidong Cement according to GB 8076-2008 "Concrete Admixtures". The initial and extended spread of the concrete, compressive strength (1d, 3d, and 28d), and workability were measured. The initial spread was controlled at 500±10mm. The results are shown in Table 1.

[0119] The concrete mix proportions are shown in Table 1, and the test data are shown in Table 2.

[0120] Table 1 Concrete mix proportions (kg / m³) 3

[0121] cement fly ash Mineral powder sand Pebbles (5-10 mm) Pebbles (10-20 mm) water 280 40 40 870 300 680 165

[0122] Table 2 Concrete Test Data

[0123]

[0124] As shown in Table 2, the anti-mud, early-strength polycarboxylate superplasticizer provided by this invention has advantages such as low dosage, minimal slump loss over time, and high early strength. This superplasticizer effectively improves the slump retention of concrete, reduces slump loss during pumping, and while enhancing concrete workability and anti-mud properties, it also helps improve pumping efficiency and avoids problems such as pipe blockage caused by excessive loss of concrete fluidity in the later stages. Furthermore, this product can significantly improve the 1-day and 3-day compressive strength of concrete and ensure stable strength growth in the later stages, thereby helping to improve the production efficiency of precast components and reduce production energy consumption.

[0125] It should be noted that the specific parameters or reagents in the above embodiments are specific or preferred embodiments under the concept of the present invention, and not limitations thereof; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.

Claims

1. An early-strength polycarboxylate water reducer against mud, characterized in that, The raw materials for preparing the anti-mud early strength polycarboxylate superplasticizer include, in mass fraction: 2.The early-strength type polycarboxylate superplasticizer according to claim 1, characterized in that, The temperature-sensitive monomer is poly(N-isopropyl acrylamide). 3.The early-strength type polycarboxylate superplasticizer according to claim 1, characterized in that, The unsaturated ester functional monomer is obtained by esterification of acrylic acid and polyethylene glycol in the presence of a catalyst and a polymerization inhibitor. 4.The early-strength type polycarboxylate superplasticizer according to claim 3, characterized in that, The polyethylene glycol is one of PEG-3000, PEG-4000 or PEG-5000. 5.The early-strength type polycarboxylate superplasticizer according to claim 1, characterized in that, The molecular weight of the ethylene glycol monovinyl polyoxyethylene ether is 2000, 2400 or 3000. 6.The early-strength type polycarboxylate superplasticizer according to claim 1, characterized in that, The unsaturated phosphoric acid monomer includes methacryloyloxyethyl phosphate. 7.The early-strength type polycarboxylate superplasticizer according to claim 1, characterized in that, The unsaturated acid monomer includes at least one of acrylic acid, methacrylic acid and itaconic acid. 8.The early-strength type polycarboxylate superplasticizer according to claim 1, characterized in that, The raw materials for preparing the anti-mud early strength polycarboxylate superplasticizer further include, in mass fraction: Oxidant 2-4 parts; Reducing agent 0.1-2 parts; Molecular weight regulator 1-5 parts. 9.The early-strength type polycarboxylate superplasticizer according to claim 8, characterized in that, The oxidant includes one of hydrogen peroxide and ammonium persulfate; The reducing agent includes at least one of sodium hypophosphite and L-ascorbic acid; The molecular weight regulator includes at least one of mercaptoethanol, mercaptopropionic acid and sulfonated mercaptopropionic acid.

10. The method for preparing the early-strength polycarboxylate water reducer against mud according to any one of claims 1-9, characterized in that, The method comprises the step of mixing and reacting ethylene glycol monovinyl polyoxyethylene ether, unsaturated acid monomer, temperature-sensitive monomer, unsaturated ester functional monomer and unsaturated phosphate monomer to obtain the anti-mud early strength polycarboxylate superplasticizer.

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