A slow-release slump-preserving material and its preparation method

Abstract

The present application relates to a kind of slow-release type slump retaining materials and its preparation method, a kind of slow-release type slump retaining materials, it is characterized in that, the preparation raw material of the slow-release type slump retaining material includes: first polyether macromonomer 60~100 parts;Unsaturated carboxylic acid (anhydride) 2~16 parts;Unsaturated phosphonate 0.5~5.0 parts;Unsaturated carboxylic acid ester 15~35 parts;Second polyether macromonomer 100 parts;Initiator 1~5 parts;Molecular weight regulator 0.5~3.2 parts;The present application selects allylamine as initiator to prepare first polyether macromonomer, and using fluorobenzene oxy group epoxy alkane to end cap polyether monomer, the first polyether macromonomer prepared, when participating in copolymerization, first polyether macromonomer molecule adsorbs in cement particle surface layer, can increase the thickness of water film layer between particles, improve the water retention of concrete, the effect of thickening pulp is remarkable, the pulp rate of concrete is slowed down, and the slump performance of concrete is improved simultaneously.

Description

Technical Field

[0001] This invention relates to the field of concrete technology, specifically to a slow-release slump-retaining material and its preparation method. Background Technology

[0002] Polycarboxylate superplasticizers have the characteristics of high water reduction, low dosage, and high slump retention, which can give concrete good fluidity, thixotropy and long-term slump retention. However, when encountering complex and variable materials such as cement, sand and stone, they are prone to problems such as rapid slump loss, poor workability and delayed bleeding.

[0003] Adding slump retainers to concrete usually solves problems such as rapid slump loss, poor workability, and delayed bleeding. Commercially available slump retainers generally have a good slump retention effect within 1 to 2 hours, but the slump retention effect of concrete is poor after 2 hours.

[0004] The transportation time required for concrete from mixing to on-site pouring has been extended due to increased urban distances and traffic congestion, with transportation times of 3 hours or more being a common phenomenon. Ordinary slump retainers do not perform well in terms of long-term slump retention (4 hours or more), leading to problems such as poor workability and bleeding in concrete. Summary of the Invention

[0005] Therefore, it is necessary to provide a slow-release slump-retaining material with a long slump-retaining time and its preparation method.

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

[0007] A slow-release slump-retaining material, wherein the raw materials for preparing the slow-release slump-retaining material, by weight, include:

[0008]

[0009]

[0010] The structural formula of the first polyether macromonomer is as follows:

[0011]

[0012] Wherein, R1 is H or -CH3;

[0013] R2 is -H, -CH3, or -C2H5;

[0014] M1 is a polyether chain obtained by ring-opening polymerization of ethylene oxide and / or propylene oxide.

[0015] Preferably, the raw materials for preparing the first polyether macromonomer, by weight, include:

[0016]

[0017] Preferably, the initiator includes at least one of 2-methylallylamine, dimethylallylamine, N-methylallylamine, and allyl ethylamine.

[0018] Preferably, the catalyst includes at least one selected from sodium methoxide, sodium tert-butoxide, sodium ethoxide, lithium aluminum hydride, sodium hydroxide, potassium hydroxide, sodium cyanide, and metallic sodium.

[0019] Preferably, the fluorophenoxy epoxide comprises at least one of [(4-fluorophenoxy)methyl] ethylene oxide, 2-[(3-fluorophenoxy)methyl] ethylene oxide, and 2-[(2-fluorophenoxy)methyl] ethylene oxide.

[0020] Preferably, the unsaturated phosphonate comprises at least one of 1-phenylvinyl phosphate, diethyl phenylpropene phosphate, and dimethyl styrene phosphate.

[0021] Preferably, the second polyether monomer includes at least one selected from allyl polyethylene glycol, 3-methyl-3-butene-1-polyethylene glycol, 2-methylallyl polyethylene glycol, vinyl glycol ether, and 4-hydroxybutyl vinyl ether.

[0022] Preferably, the unsaturated carboxylic acid (anhydride) includes at least one selected from acrylic acid, methacrylic acid, fumaric acid, itaconic acid, maleic anhydride, and itaconic anhydride.

[0023] The present invention also provides a method for preparing the slow-release slump-retaining material as described above, comprising the steps of:

[0024] The first polyether macromonomer, unsaturated carboxylic acid (anhydride), unsaturated phosphonate, unsaturated carboxylic acid ester, second polyether macromonomer and water are mixed to obtain a comonomer mixture solution;

[0025] The comonomer mixture solution, initiator, and molecular weight regulator are mixed and reacted. After the reaction is completed, a slow-release, slump-preserving mother liquor is obtained.

[0026] The slow-release slump-preserving mother liquor was distilled, dehydrated, cooled, and pulverized to obtain the slump-preserving material.

[0027] The slump retainer and the polymer slow-release material are stirred evenly to obtain a mixture;

[0028] The mixture is dried, cooled, and pulverized to obtain the slow-release slump-preserving material.

[0029] Preferably, the polymeric sustained-release material is polycaprolactone with a molecular weight of 10,000 to 50,000.

[0030] The beneficial effects of this invention are:

[0031] 1. In this invention, allylamine is selected as the initiator to prepare the first polyether macromonomer, and fluorophenoxyepoxide is used to end-cap the polyether macromonomer. When the first polyether macromonomer participates in the copolymerization reaction, the first polyether macromonomer molecules are adsorbed on the surface of cement particles, which can increase the thickness of the water film layer between particles, improve the water retention of concrete, significantly improve the slurry raising effect, and slow down the slurry setting rate of concrete.

[0032] 2. The raw materials for preparing the first polyether macromonomer in this invention include an initiator and a fluorophenoxy epoxy alkane. The first polyether macromonomer is prepared by introducing an initiator containing an amino group and a fluorophenoxy epoxy alkane containing a fluorophenyl group. The first polyether macromonomer is introduced into the side chain, while the main chain contains functional groups such as phenyl phosphate ester, carboxyl ester, carboxyl group, and hydroxyl group. The main chain and side chain work together synergistically, and the rigid structure of the benzene ring allows the hydration regulator molecules to attach to the surface of cement particles, and the molecular chain is fully extended, increasing the fluidity of cement particles and making them less prone to agglomeration.

[0033] 3. This invention introduces unsaturated phosphonates with phosphate ester structures. Since the phenyl phosphate ester monomer of the first polyether macromonomer carries multiple negative charges, it has strong adsorption properties. The phosphate ester structure and carboxylic acid ester structure in the main chain coordinate with each other and continuously hydrolyze in the strong alkaline system of concrete. The released phosphate ions participate in the reaction of cement hydration products, coat the surface of cement particles, and slow down the hydration rate.

[0034] 4. The slump-retaining material prepared in this invention incorporates a polymer slow-release material, which serves as a slow-release layer. This material can slowly degrade within the cement system, achieving a non-slow-release effect in the initial stage of concrete mixing, but releasing slowly in the later stage, further extending the slump-retaining effect of the concrete. It can maintain slump retention for 5 hours without loss, resulting in good workability, no bleeding, and no backflow. In addition, the introduction of this functional monomer also inhibits the loss of moisture in the concrete, providing water retention and slurry enhancement effects, making it suitable for concrete projects with high slump retention requirements. Detailed Implementation

[0035] 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.

[0036] 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.

[0037] A slow-release slump-retaining material, wherein the raw materials for preparing the slow-release slump-retaining material, by weight, include:

[0038]

[0039] The structural formula of the first polyether macromonomer is as follows:

[0040]

[0041] Wherein, R1 is H or -CH3;

[0042] R2 is -H, -CH3, or -C2H5;

[0043] M1 is a polyether chain obtained by ring-opening polymerization of ethylene oxide and / or propylene oxide.

[0044] In one embodiment, the raw materials for preparing the first polyether macromonomer, by weight, include:

[0045]

[0046] In one embodiment, the initiator includes at least one selected from 2-methylallylamine, dimethylallylamine, N-methylallylamine, and allyl ethylamine.

[0047] Specifically, the general structural formula of the initiator is as follows:

[0048]

[0049] Wherein, R1 is H or -CH3;

[0050] R2 is -H, -CH3, or -C2H5;

[0051] In one embodiment, the catalyst includes at least one selected from sodium methoxide, sodium tert-butoxide, sodium ethoxide, lithium aluminum hydride, sodium hydroxide, potassium hydroxide, sodium cyanide, and metallic sodium.

[0052] In one embodiment, the fluorophenoxy epoxide comprises at least one of [(4-fluorophenoxy)methyl] ethylene oxide, 2-[(3-fluorophenoxy)methyl] ethylene oxide, and 2-[(2-fluorophenoxy)methyl] ethylene oxide.

[0053] Specifically, the structural formula of the fluorophenoxyepoxide is as follows:

[0054]

[0055] In this case, -F and -O- on the benzene ring can be ortho, meta, or para.

[0056] In one embodiment, the alkylene oxide is ethylene oxide and / or propylene oxide.

[0057] More specifically, the preparation steps of the first polyether macromonomer are as follows:

[0058] Add the initiator and catalyst to the reactor, evacuate to -0.1 to -0.2 MPa, replace with N2 to remove oxygen, raise the reaction temperature to 90 to 130°C, introduce epoxide alkane into the reactor, the reaction pressure is 0.2 to 5 MPa, and the reaction is carried out for 1 to 3 hours.

[0059] Once the pressure in the reactor stops decreasing, evacuate to -0.1 to -0.2 MPa. Then, introduce fluorophenoxy epoxide into the reactor and maintain the temperature at 90 to 130°C. When the pressure in the reactor stops decreasing, the reaction is complete, and the first polyether macromonomer is obtained.

[0060] In one embodiment, the unsaturated phosphonate comprises at least one of 1-phenylvinyl phosphate, diethyl phenylpropene phosphate, and dimethyl styrene phosphate.

[0061] In one embodiment, the second polyether monomer includes at least one of allyl polyethylene glycol, 3-methyl-3-butene-1-polyethylene glycol, 2-methylallyl polyethylene glycol, vinyl glycol ether, and 4-hydroxybutyl vinyl ether, with a molecular weight of 800 to 6000.

[0062] In one embodiment, the unsaturated carboxylic acid (anhydride) includes at least one selected from acrylic acid, methacrylic acid, fumaric acid, itaconic acid, maleic anhydride, and itaconic anhydride.

[0063] In one embodiment, the initiator is a water-soluble inorganic peroxide initiator, a water-soluble redox initiation system, or a water-soluble azo initiator;

[0064] In one embodiment, the unsaturated carboxylic acid ester includes at least one selected from hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, isooctyl acrylate, isooctyl methacrylate, and methyl methacrylate.

[0065] The water-soluble inorganic peroxide initiator includes at least one of ammonium persulfate and potassium persulfate;

[0066] The water-soluble redox initiation system includes at least one of hydrogen peroxide / sodium formaldehyde sulfoxylate, hydrogen peroxide / ascorbic acid, and persulfate / sodium bisulfite;

[0067] The water-soluble azo initiator includes at least one of azobisisobutylamidine hydrochloride, azobisisopropylimidazoline hydrochloride, azobiscyanopentanoic acid, and azobisisopropylimidazoline.

[0068] In one embodiment, the molecular weight regulator includes at least one of mercaptoacetic acid, mercaptopropionic acid, mercaptoethanol, isopropanol, sodium hypophosphite, trisodium phosphate, sodium formate, sodium acetate, and dodecyl mercaptan.

[0069] The present invention also provides a method for preparing the slow-release slump-retaining material as described above, comprising the steps of:

[0070] The first polyether macromonomer, unsaturated carboxylic acid (anhydride), unsaturated phosphonate, unsaturated carboxylic acid ester, second polyether macromonomer and water are mixed to obtain a comonomer mixture solution;

[0071] The comonomer mixture solution, initiator, and molecular weight regulator are mixed and reacted. After the reaction is completed, a slow-release slump-preserving mother liquor is obtained. (Specifically, the comonomer mixture solution, initiator, and molecular weight regulator are added dropwise to a reaction vessel containing water. The stirrer is turned on to carry out the reaction. The reaction temperature is 5-50°C, the dropwise addition time is 1.0-1.5 hours, and after the dropwise addition is completed, the reaction continues for 0.5-2.0 hours. Then, the pH is adjusted to 5-7 with an alkali to obtain the slow-release slump-preserving mother liquor. The alkali includes, but is not limited to, sodium hydroxide and potassium hydroxide.)

[0072] The slow-release slump-preserving mother liquor was distilled, dehydrated, cooled, and pulverized to obtain the slump-preserving material.

[0073] The slump retainer and the polymer slow-release material are stirred evenly to obtain a mixture; (the negative pressure value for distillation and dehydration is 0.2 MPa, the temperature is 40-80℃, and the dehydration time is 2-5 h).

[0074] The mixture is dried, cooled, and pulverized to obtain the slow-release slump-preserving material.

[0075] In one embodiment, the polymeric sustained-release material is polycaprolactone with a molecular weight of 10,000 to 50,000. The mass ratio of the slump retainer to the polymeric sustained-release material is (0.5 to 5):1.

[0076] Example

[0077] 1. Preparation of the first polyether macromonomer

[0078] Initiator and catalyst are added to the reactor, vacuum is drawn to -0.1 MPa, and oxygen is removed by replacing with N2. The reaction temperature is raised to 90-130℃ (T1), epoxide is introduced into the reactor, the reaction pressure is 0.2-5 MPa, and the reaction is carried out for 1-3 hours.

[0079] Once the pressure in the reactor stops decreasing, evacuate to -0.1 MPa, then introduce a sealing agent into the reactor and maintain the temperature at 90–130 °C (T2). When the pressure in the reactor stops decreasing, the reaction ends, and the first polyether macromonomer A is obtained.

[0080] The reactants and reaction conditions for preparing the first polyether macromonomer A in each embodiment are shown in Table 1.

[0081] Table 1. Reactants and reaction conditions for preparing the first polyether macromonomer A in each embodiment.

[0082]

[0083] 2. Slow-release slump-retaining materials

[0084] (a) The first polyether macromonomer A obtained in step 1 is mixed with unsaturated carboxylic acid (anhydride), unsaturated phosphonate, unsaturated carboxylic acid ester and the second polyether macromonomer, and water is added to dissolve it to obtain a comonomer mixture solution B. The components and amounts of the comonomer mixture solution B are shown in Table 2.

[0085] Table 2. Components and Dosage of Comonomer Mixture Solution B

[0086]

[0087] (b) The above-mentioned copolymer monomer mixture solution B, initiator and molecular weight regulator were added dropwise into a reaction vessel containing water. The stirrer was turned on to carry out the reaction. The reaction temperature was 5-50℃ and the dropwise addition time was 1.0-1.5h. After the dropwise addition was completed, the reaction was continued for 0.5-2.0h to obtain the copolymer product. The pH was then adjusted to 5-7 with alkali to obtain the slow-release slump-preserving mother liquor C. The reactants and reaction conditions for preparing the slow-release slump-preserving mother liquor C are shown in Table 3.

[0088] Table 3. Reactants and reaction conditions for preparing sustained-release slump-retaining mother liquor C

[0089]

[0090] (c) Dehydration, pulverization, and coating

[0091] (1) Dehydration and pulverization: The slow-release polycarboxylate slump retainer C1 prepared above is transferred to a distillation flask, the vacuum pump is turned on, the negative pressure value is 0.2MPa, the temperature is raised to 50℃, and dehydration is carried out by vacuum distillation. The dehydrated material is then cooled and pulverized to obtain the slump retainer material.

[0092] Coating: Add 400g of slump-preserving material to a flask containing 100g of molten polycaprolactone with a molecular weight of 10000, heat to 60℃, and stir for 1.5h to fully combine and mix the molten polycaprolactone with the slump-preserving agent to obtain a mixture; then dry the obtained mixture in a drum, cool and pulverize it to obtain the slow-release slump-preserving material KZJ-1.

[0093] (2) Transfer the liquid high-temperature slow-release polycarboxylate slump retainer C2 prepared above into a distillation flask, turn on the vacuum pump, set the negative pressure value to 0.2 MPa, raise the temperature to 60°C, and perform vacuum distillation to dehydrate. Then cool and crush the dehydrated material to obtain the slump retainer material.

[0094] Then, 420g of slump-preserving material was added to a flask containing 100g of molten polycaprolactone with a molecular weight of 20,000. The temperature was raised to 60°C and stirred for 1.5h to allow the molten polycaprolactone and the slump-preserving agent to fully combine and mix. The resulting mixture was then dried by drum drying, cooled, and pulverized to obtain slow-release long-lasting slump-preserving material KZJ-2.

[0095] (3) Transfer the liquid high-temperature slow-release polycarboxylate slump retainer C3 prepared above into a distillation flask, turn on the vacuum pump, set the negative pressure value to 0.2 MPa, raise the temperature to 70°C, and perform vacuum distillation to dehydrate. Then cool and crush the dehydrated material to obtain the slump retainer material.

[0096] Then, 380g of slump-preserving material was added to a flask containing 100g of molten polycaprolactone with a molecular weight of 16000. The temperature was raised to 60℃ and stirred for 1.0h to allow the molten polycaprolactone and slump-preserving agent to fully combine and mix to obtain a mixture. The obtained mixture was then dried by drum drying, cooled, and pulverized to obtain slow-release long-lasting slump-preserving material KZJ-3.

[0097] (4) Transfer the liquid high-temperature slow-release polycarboxylate slump retainer C4 prepared above into a distillation flask, turn on the vacuum pump, set the negative pressure value to 0.2 MPa, raise the temperature to 50°C, and perform vacuum distillation to dehydrate. Then cool and crush the dehydrated material to obtain the slump retainer material.

[0098] Add 400g of slump-preserving material to a flask containing 100g of molten polycaprolactone with a molecular weight of 30,000, heat to 60℃, and stir for 2.0h to fully combine and mix the molten polycaprolactone with the slump-preserving agent to obtain a mixture; then dry the obtained mixture in a drum, cool and pulverize it to obtain the slow-release long-lasting slump-preserving material KZJ-4.

[0099] (5) Transfer the liquid high-temperature slow-release polycarboxylate slump retainer C5 prepared above into a distillation flask, turn on the vacuum pump, set the negative pressure value to 0.2 MPa, raise the temperature to 60°C, and perform vacuum distillation to dehydrate. Then cool and pulverize the dehydrated material to obtain the slump retainer material.

[0100] Add 400g of slump-preserving material to a flask containing 100g of molten polycaprolactone with a molecular weight of 40,000, heat to 60°C, and stir for 1.0h to fully combine and mix the molten polycaprolactone with the slump-preserving agent to obtain a mixture; then dry the obtained mixture in a drum, cool and pulverize it to obtain the slow-release long-lasting slump-preserving material KZJ-5.

[0101] (6) Transfer the liquid high-temperature slow-release polycarboxylate slump retainer C6 prepared above into a distillation flask, turn on the vacuum pump, set the negative pressure value to 0.2 MPa, raise the temperature to 60°C, and perform vacuum distillation to dehydrate. Then cool and pulverize the dehydrated material to obtain the slump retainer material.

[0102] Then, 320g of slump-preserving material was added to a flask containing 100g of molten polycaprolactone with a molecular weight of 50,000. The temperature was raised to 60°C and stirred for 2.0h to allow the molten polycaprolactone and the slump-preserving agent to fully combine and mix. The resulting mixture was then dried by drum drying, cooled, and pulverized to obtain slow-release long-lasting slump-preserving material KZJ-6.

[0103] Comparative Example 1

[0104] Commercially available concrete slump retaining material with model number BSF-412 is designated as BT-1.

[0105] Comparative Example 2

[0106] Based on the process described in Section 1, BT-2 was prepared by not adding the first polyether macromonomer A1 when preparing the sustained-release slump-retaining material, while keeping other reaction conditions unchanged.

[0107] Comparative Example 3

[0108] Based on the process described in List 1, BT-3 is prepared without the coating treatment with polymer slow-release material (i.e., the step of "adding 400g of slump-preserving material to a flask containing 100g of molten polycaprolactone, heating to 60°C, stirring for 1.5h to fully combine and mix the molten polycaprolactone with the slump-preserving agent to obtain a mixture; then drying the obtained mixture by drum drying, cooling, and pulverizing"). The slump-preserving material is directly used as BT-3. Other reaction conditions remain unchanged.

[0109] Comparative Example 4

[0110] Based on the process described in Section 1, BT-4 was prepared by replacing A1 with commercially available conventional EPEG-3000 polyether macromonomer.

[0111] Comparative Example 5

[0112] Based on the process described in Section 1, BT-5 was prepared by replacing A1 with commercially available conventional TPEG-2400 polyether macromonomer while keeping other reaction conditions unchanged.

[0113] Comparative Example 6

[0114] Based on the process described in Section 1, without adding unsaturated phosphate esters and keeping other reaction conditions unchanged, BT-6 was prepared.

[0115] Performance testing:

[0116] The slump retainers prepared in Examples 1-6 and Comparative Examples 1-6 were compounded with PointTS08 water-reducing agent from Kezhijie at a ratio of 5:5 to form samples with a solid content of 10%. When the dosage of Examples 1-6 was 1.0% (relative to the amount of cementitious material), the water reduction rate was higher than 34%, the 1-day compressive strength ratio was greater than 200%, the 28-day compressive strength ratio was greater than 170%, and the 28-day shrinkage ratio was less than 60%.

[0117] Runfeng P.O42.5 ordinary Portland cement was used, and the concrete mix proportions were as follows:

[0118] 240kg / m³ of cement 3 90kg / m³ of fly ash 3 30kg / m³ of mineral powder 3 820kg / m³ of manufactured sand 3 1020 kg / m³ of gravel 3 170kg / m³ of water 3 .

[0119] The performance of the slump retainers prepared in Examples 1-6 and Comparative Examples 1-6 were compared according to the above admixture formulations. The admixture dosage was adjusted to achieve an initial concrete spread of (600±10) mm. Test indicators included concrete flow after 0h, 2h, 3h, 4h, and 5h, bleeding rate, and compressive strength at various ages. The results are shown in Table 4.

[0120] Table 4 Experimental Results

[0121]

[0122]

[0123] From the experimental results in Table 4 above, we can conclude that:

[0124] 1) The slump-retaining material prepared by this invention can achieve long-term slump retention for 5 hours. After 5 hours, it has good fluidity and does not exhibit bleeding or excessive hysteresis. The fluidity remains stable, and it has good encapsulation and workability.

[0125] 2) Commercially available slump retainer BT-1, with a higher dosage than the patented product of this invention, can only maintain slump retention for 2 hours. After 3 hours, it has almost no fluidity. Its slump retention performance is not as good as the patented product of this invention. It has a high water bleeding rate and lower strength than the product of this invention.

[0126] 3) Comparative product BT-2, based on Example 1, without the coating treatment of polymer slow-release material, can only maintain slump retention for 3 hours. After 4 hours, it loses its fluidity very quickly and cannot achieve 5 hours of slump retention. Its slump retention performance is not as good as the product of this invention, its strength is lower than the product of this invention, its workability is good, and it has a delayed water seepage phenomenon.

[0127] 4) Comparative products BT-3, BT-4 and BT-5, based on Example 1, were synthesized without polyether macromonomer A or by replacing A with other polyether monomers. The dosage was higher than that of this invention patent, the workability was poor, and all of them showed hysteresis return and bleeding. Moreover, the slump retention time could only be maintained for 2 hours, and the loss began after 2 hours.

[0128] 5) The comparative product BT-6 has better slump retention performance than other comparative products, but its slump retention is not as good as the product of this invention. The workability of the concrete is not good, and there is a delayed bleeding phenomenon in the loss.

[0129] It should be noted that the specific parameters or reagents in the above embodiments are specific or preferred embodiments under the concept of the present invention, and not limitations thereof; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.

Claims

1. A slump-retaining material of the slow-release type, characterized in that, The preparation raw materials of the slow-release slump retaining material include, in terms of weight parts: The structural formula of the first polyether macromonomer is as follows: R1 is H or -CH3; R2 is -H, -CH3 or -C2H5; M1 is a polyether chain obtained by ring-opening polymerization of ethylene oxide and / or propylene oxide.

2. The slump-retaining material of claim 1, wherein, The high molecular slow-release material is polycaprolactone with a molecular weight of 10,000-50,000.

3. The slump-retaining material of claim 1, wherein, The preparation raw materials of the first polyether macromonomer include, in terms of weight parts:

4. The slump retention material of claim 3, wherein, The initiator includes at least one of 2-methylallylamine, dimethylallylamine, N-methylallylamine and allyl ethylamine.

5. The slump retention material of claim 3, wherein, The catalyst includes at least one of sodium methoxide, sodium tert-butoxide, sodium ethoxide, lithium aluminum hydride, sodium hydroxide, potassium hydroxide, sodium cyanide and metallic sodium.

6. The slump retention material of claim 3, wherein, The fluorophenoxy alkylene oxide includes at least one of [(4-fluorophenoxy)methyl]oxirane, 2-[(3-fluorophenoxy)methyl]oxirane and 2-[(2-fluorophenoxy)methyl]oxirane.

7. The slump-retaining material of claim 1, wherein, The unsaturated phosphonate includes at least one of 1-phenylvinyl phosphate, diethyl phenylpropenyl phosphonate and dimethyl styryl phosphonate.

8. The slump-retaining material of claim 1, wherein, The second polyether monomer includes at least one of allyl polyethylene glycol, 3-methyl-3-butene-1-polyethylene glycol, 2-methylallyl polyethylene glycol, vinyl glycol ether and 4-hydroxybutyl vinyl ether.

9. The slump-retaining material of claim 1, wherein, The unsaturated carboxylic acid and / or unsaturated carboxylic anhydride includes at least one of acrylic acid, methacrylic acid, fumaric acid, itaconic acid, maleic anhydride and itaconic anhydride.

10. A method of preparing the slump retention material of any one of claims 1 to 9, characterized in that, The method includes the steps of: Mixing the first polyether macromonomer, unsaturated carboxylic acid and / or unsaturated carboxylic anhydride, unsaturated phosphonate, unsaturated carboxylic ester, second polyether macromonomer and water to obtain a comonomer mixture solution; Mixing the comonomer mixture solution, initiator and molecular weight regulator to react, and the slow-release slump retaining mother liquor is obtained after the reaction; Performing distillation dehydration, cooling and crushing treatment on the slow-release slump retaining mother liquor to obtain a slump retaining material; Stirring the slump retaining agent and high molecular slow-release material uniformly to obtain a mixture; Performing drying, cooling and crushing treatment on the mixture to obtain the slow-release slump retaining material.

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