A concrete retarder and a preparation method thereof

Abstract

This application relates to the field of concrete admixtures, specifically disclosing a concrete retarder and its preparation method. The concrete retarder comprises the following raw materials in parts by weight: 40-60 parts of an organophosphorus retarding component, 20-30 parts of a hydrolyzed protein carrier, 1-3 parts of a thickener, 2-6 parts of an emulsifier, and 10-16 parts of additives. The preparation method is as follows: the additives and organophosphorus retarding component are mixed and stirred evenly; the mixture is heated to 75°C, then the thickener and emulsifier are added and stirred for 10 minutes; then the hydrolyzed protein carrier is added and stirring is continued for 20 minutes; the mixture is cooled to room temperature to obtain the concrete retarder. The concrete retarder of this application can be used to reduce the adverse effects of retarders on the later-stage strength of concrete.

Description

Technical Field

[0001] This application relates to the field of concrete admixtures, and more specifically, to a concrete retarder and a method for its preparation. Background Technology

[0002] Retarder is an admixture that delays the cement hydration reaction, thereby extending the setting time of concrete, allowing fresh concrete to maintain its plasticity for a longer period, thus facilitating pouring and improving construction efficiency, while not causing significant adverse effects on the later performance of the concrete.

[0003] Commonly used retarders include organic acids and their soluble salts, alkaline phosphates, and protein retarders. Among them, organic acids and their soluble salts, as well as phosphate retarders, significantly reduce the strength of building gypsum. The higher the dosage, the more obvious the strength reduction. Summary of the Invention

[0004] In order to reduce the adverse effects of retarders on the later strength of concrete, this application provides a concrete retarder and its preparation method.

[0005] In a first aspect, this application provides a concrete retarder, which adopts the following technical solution:

[0006] A concrete retarder comprises the following raw materials in parts by weight: 40-60 parts of organophosphorus retarding component, 20-30 parts of hydrolyzed protein carrier, 1-3 parts of thickener, 2-6 parts of emulsifier, and 20-30 parts of additive.

[0007] By adopting the above technical solution, the additives allow the organophosphorus retarding component to be diluted and combined with the hydrolyzed protein carrier, thereby loading the organophosphorus retarding component onto the hydrolyzed protein carrier. Then, the overall stability of the retarder is improved by emulsifiers and thickeners. The combination of the organophosphorus retarding component and the hydrolyzed protein carrier enables the retarder to maintain its retarding ability while reducing its adverse effects on the later strength of concrete.

[0008] Preferably, the organophosphorus retarder component is prepared from the following raw materials: diethylenetriamine, phosphorous acid, formaldehyde, carbon-linked grafting agent, and amino-linked grafting agent.

[0009] By adopting the above technical solution, phosphorous acid and formaldehyde are linked to the carbon chain through the Mannich reaction, thereby enhancing the adsorption of calcium ions by diethylenetriamine and inhibiting the early hydration of cement. The carbon linking agent adds carbon chains to the central N and further extends the carbon chains through the amino grafting agent, so that the final product extends from the central N to three phosphorous acid-containing carbon chains of the same length. Due to the addition of carbon chains, the branches of the final product become longer, the overall toughness is enhanced, and the structure of the final product is stable. The carbon chain lengthening makes the final product easier to knot and adsorb calcium ions, improving the performance of the retarder. At the same time, the final product can also easily combine with hydrolyzed protein carriers and additives to compensate for the decrease in the later strength of concrete caused by the addition of retarder.

[0010] Preferably, the organophosphorus retarder is prepared by the following steps: heating a diethylenetriamine solution to 100-140°C, adding phosphorous acid, formaldehyde, carbon grafting agent, amino grafting agent and sulfuric acid, stirring and mixing evenly, maintaining the reaction at 100-140°C for 14-18 hours, then cooling to room temperature and adding a 30% sodium hydroxide aqueous solution to neutralize to pH 5, thus obtaining the organophosphorus retarder.

[0011] By adopting the above technical solution, phosphorous acid firstly undergoes a Mannich reaction between formaldehyde and diethylenetriamine, thereby indirectly linking phosphorous acid to the carbons at both ends of diethylenetriamine. Then, carbon linking agents and amino grafting agents extend the carbon chain on the middle N and indirectly link it to phosphorous acid, thereby extending three identical carbon chains from the middle N, effectively improving the structural stability of organophosphorus retarder components.

[0012] Preferably, the amino grafting agent is monomethylamine.

[0013] By adopting the above technical solution, when monomethylamine is used as an amino grafting agent, the carbon grafting agent adds a new carbon chain on N, and then adds groups that can be further substituted, so that phosphorous acid can be indirectly connected to N through the added carbon chain, making the final product structure more stable.

[0014] Preferably, the carbon linking agent is glyoxal.

[0015] By adopting the above technical solution, glyoxal adds a carbon chain on N and indirectly connects it with monomethylamine, further increasing the carbon chain length, so that the carbon chain connected on N in the final product has the same length and the structure is more stable.

[0016] Preferably, the hydrolyzed protein carrier is prepared by the following steps: first, acid hydrolyzing the protein raw material to obtain acid hydrolyzed protein mother liquor, neutralizing the acid hydrolyzed protein mother liquor to obtain hydrolyzed protein mother liquor, and spray drying the hydrolyzed protein mother liquor to obtain powdered hydrolyzed protein carrier.

[0017] By adopting the above technical solution, the protein raw material is first acidified and then adjusted to form a hydrolyzed protein mother liquor, which is convenient for subsequent spray drying to obtain a carrier for loading organophosphorus retarding components.

[0018] Preferably, the additive is a long-chain fatty acid.

[0019] By adopting the above technical solution, the additive first dilutes the organophosphorus retarding component, so that the hydrolyzed protein carrier is evenly dispersed in the organophosphorus retarding component. During the later stage of concrete strength formation, the long chain of the additive causes the organophosphorus retarding component to be tightly entangled and combined with the hydrolyzed protein carrier and other components, thereby effectively compensating for the later stage of concrete strength and reducing the adverse effects of the addition of the retarder on the later stage of concrete strength.

[0020] Secondly, this application provides a method for preparing a concrete retarder, which adopts the following technical solution: A method for preparing a concrete retarder includes the following steps: mixing and stirring the additive with the organophosphorus retarding component until uniform, heating to 75°C and then adding the hydrolyzed protein carrier and stirring for 10 min, then adding the thickener and emulsifier and continuing to stir for 20 min, and cooling to room temperature to obtain the concrete retarder.

[0021] By adopting the above technical solution, the organophosphorus retarding component is first mixed and stirred evenly with additives, then hydrolyzed protein carrier is added for loading, and then the retarder is adjusted with emulsifiers and thickeners, so that the overall performance of the retarder is more stable.

[0022] In summary, this application has the following beneficial effects:

[0023] 1. Because the additives in this application allow the organophosphorus retarding component to be diluted and then combined with the hydrolyzed protein carrier, the organophosphorus retarding component is loaded onto the hydrolyzed protein carrier. Then, the overall stability of the retarder is improved by emulsifiers and thickeners. The combination of the organophosphorus retarding component and the hydrolyzed protein carrier enables the retarder to maintain its retarding ability while reducing its adverse effects on the later strength of concrete.

[0024] 2. In this application, phosphorous acid and formaldehyde are linked to the carbon chain via the Mannich reaction, thereby enhancing the adsorption of calcium ions by diethylenetriamine and inhibiting the early hydration of cement. The carbon linking agent adds carbon chains to the central N and further extends the carbon chains through an amino grafting agent, resulting in the final product extending from the central N to three phosphorous acid-containing carbon chains of equal length. Due to the subsequent addition of carbon chains, the final product has longer branches, enhanced overall toughness, and thus a stable structure. The increased carbon chain length makes the final product easier to agglomerate and adsorb calcium ions, improving the performance of the retarder. At the same time, the final product is also easier to combine with hydrolyzed protein carriers and additives, compensating for the decrease in concrete strength in the later stages caused by the addition of the retarder.

[0025] 3. In this application, the organophosphorus retarder component is first mixed and stirred evenly with additives, then hydrolyzed protein carrier is added for loading, and then the retarder is adjusted with emulsifiers and thickeners to make the overall performance of the retarder more stable. Detailed Implementation

[0026] In this application, oleic acid, palmitic acid, and stearic acid were purchased from commercial sources; diethylenetriamine was analytical grade with a purity ≥99%; phosphorous acid was analytical grade with a purity ≥99%; formaldehyde was a 37% aqueous solution; glyoxal was a 40% aqueous solution; monomethylamine was a 40% ethanolic solution; sulfuric acid was 98% concentrated sulfuric acid; industrial gelatin was kraft glue granules with an effective component of 90%; the emulsifier was fatty acid monoglyceride; and the thickener was a polyurethane associative thickener.

[0027] The present application will be further described in detail below with reference to the embodiments.

[0028] Preparation Example

[0029] Preparation Example 1

[0030] This preparation example discloses an organophosphorus retarder component, which is prepared by the following steps:

[0031] S1. Mix 10.3 kg of diethylenetriamine with 60 kg of water to prepare an aqueous solution of diethylenetriamine, and heat it to 100°C;

[0032] S2, add 24.6 kg phosphorous acid, 29.2 kg formaldehyde, 14.5 kg glyoxal, 17 kg monomethylamine and 12 kg sulfuric acid, stir and mix evenly, and maintain 100℃ for 14 h.

[0033] S3. After cooling to room temperature, add a 30% sodium hydroxide aqueous solution to neutralize to pH 5, thus obtaining the organophosphorus retarder component.

[0034] Preparation Example 2

[0035] This preparation example discloses an organophosphorus retarder component, which is prepared by the following steps:

[0036] S1. Mix 10.3 kg of diethylenetriamine with 60 kg of water to prepare an aqueous solution of diethylenetriamine, and heat it to 120°C;

[0037] S2, add 24.6 kg phosphorous acid, 16.2 kg formaldehyde, 14.5 kg glyoxal, 17 kg monomethylamine and 12 kg sulfuric acid, stir and mix evenly, and maintain 120℃ for 16 h.

[0038] S3. After cooling to room temperature, add a 30% sodium hydroxide aqueous solution to neutralize to pH 5, thus obtaining the organophosphorus retarder component.

[0039] Preparation Example 3

[0040] This preparation example discloses an organophosphorus retarder component, which is prepared by the following steps:

[0041] S1. Mix 10.3 kg of diethylenetriamine with 60 kg of water to prepare an aqueous solution of diethylenetriamine, and heat it to 140°C;

[0042] S2, add 24.6 kg phosphorous acid, 16.2 kg formaldehyde, 14.5 kg glyoxal, 17 kg monomethylamine and 12 kg sulfuric acid, stir and mix evenly, and maintain the reaction at 140℃ for 18 h;

[0043] S3. After cooling to room temperature, add a 30% sodium hydroxide aqueous solution to neutralize to pH 5, thus obtaining the organophosphorus retarder component.

[0044] Preparation Example 4

[0045] This preparation example discloses an organophosphorus retarder component, which is prepared by the following steps:

[0046] S1. Mix 10.3 kg of diethylenetriamine with 60 kg of water to prepare an aqueous solution of diethylenetriamine, and heat it to 120°C;

[0047] S2. Add 24.6 kg phosphorous acid, 16.2 kg formaldehyde, 17 kg monomethylamine and 12 kg sulfuric acid and stir to mix evenly. Maintain the reaction temperature at 120℃ for 16 h.

[0048] S3. After cooling to room temperature, add a 30% sodium hydroxide aqueous solution to neutralize to pH 5, thus obtaining the organophosphorus retarder component.

[0049] Preparation Example 5

[0050] This preparation example discloses an organophosphorus retarder component, which is prepared by the following steps:

[0051] S1. Mix 10.3 kg of diethylenetriamine with 60 kg of water to prepare an aqueous solution of diethylenetriamine, and heat it to 120°C;

[0052] S2, add 24.6 kg phosphorous acid, 16.2 kg formaldehyde, 14.5 kg glyoxal and 12 kg sulfuric acid, stir and mix evenly, and maintain 120℃ for 16 h.

[0053] S3. After cooling to room temperature, add a 30% sodium hydroxide aqueous solution to neutralize to pH 5, thus obtaining the organophosphorus retarder component.

[0054] Preparation Example 6

[0055] This preparation example discloses an organophosphorus retarder component, which is prepared by the following steps:

[0056] S1. Mix 10.3 kg of diethylenetriamine with 60 kg of water to prepare an aqueous solution of diethylenetriamine, and heat it to 120°C;

[0057] S2. Add 24.6 kg of phosphorous acid, 16.2 kg of formaldehyde and 12 kg of sulfuric acid and stir to mix evenly. Maintain the reaction temperature at 120℃ for 16 h. S3. After cooling to room temperature, add 30% sodium hydroxide aqueous solution to neutralize to pH 5 to obtain the organophosphorus retarder component.

[0058] Preparation Example 7

[0059] This preparation example discloses an organophosphorus retarder component, which is prepared by the following steps:

[0060] S1. Mix 10.3 kg of diethylenetriamine with 60 kg of water to prepare an aqueous solution of diethylenetriamine, and heat it to 120°C;

[0061] S2. Add 24.6 kg of phosphorous acid, 29.2 kg of formaldehyde and 12 kg of sulfuric acid and stir until well mixed. Maintain the reaction temperature at 120℃ for 16 h. S3. After cooling to room temperature, add 30% sodium hydroxide aqueous solution to neutralize to pH 5 to obtain the organophosphorus retarder component.

[0062] Preparation Example 8

[0063] This preparation example discloses a hydrolyzed protein carrier, which is prepared by the following steps:

[0064] S1. Acid hydrolysis: Mix 35 kg of industrial gelatin, 10 kg of 30% hydrochloric acid solution and 50 kg of water, and reflux at 110°C for 6 h to obtain acid hydrolyzed protein mother liquor.

[0065] S2. Hydrolysis: Cool the acid-hydrolyzed protein mother liquor to 35°C, add 10% calcium hydroxide solution to adjust the pH to 7, and obtain the hydrolyzed protein mother liquor.

[0066] S3. Drying: The hydrolyzed protein mother liquor is dried in a spray drying tower to produce powdered hydrolyzed protein carrier.

[0067] Preparation Example 9

[0068] This preparation example discloses a hydrolyzed protein carrier, which is prepared by the following steps:

[0069] S1. Acid hydrolysis: Mix 35 kg of industrial gelatin, 10 kg of 30% hydrochloric acid solution and 50 kg of water, and reflux at 115°C for 7 h to obtain acid hydrolyzed protein mother liquor.

[0070] S2. Hydrolysis: Cool the acid-hydrolyzed protein mother liquor to 40°C, add 10% calcium hydroxide solution to adjust the pH to 8, and obtain the hydrolyzed protein mother liquor.

[0071] S3. Drying: The hydrolyzed protein mother liquor is dried in a spray drying tower to produce powdered hydrolyzed protein carrier.

[0072] Preparation Example 10

[0073] This preparation example discloses a hydrolyzed protein carrier, which is prepared by the following steps:

[0074] S1. Acid hydrolysis: Mix 35 kg of industrial gelatin, 10 kg of 30% hydrochloric acid solution and 50 kg of water, and reflux at 120°C for 8 h to obtain acid hydrolyzed protein mother liquor.

[0075] S2. Hydrolysis: Cool the acid-hydrolyzed protein mother liquor to 45°C, add 10% calcium hydroxide solution to adjust the pH to 9, and obtain the hydrolyzed protein mother liquor.

[0076] S3. Drying: The hydrolyzed protein mother liquor is dried in a spray drying tower to produce powdered hydrolyzed protein carrier.

[0077] Example

[0078] Example 1

[0079] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0080] S1. Mix 20 kg of oleic acid as an additive and 40 kg of the organophosphorus retarding component prepared in Preparation Example 1 until homogeneous; S2. Heat to 75°C and add 20 kg of the hydrolyzed protein carrier prepared in Preparation Example 8 and stir for 10 min.

[0081] S3. Add 1 kg of thickener and 2 kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0082] Example 2

[0083] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0084] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 2 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0085] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0086] Example 3

[0087] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0088] S1. Mix 30 kg of oleic acid as an additive and 60 kg of the organophosphorus retarding component prepared in Preparation Example 3 until homogeneous; S2. Heat to 75°C and add 30 kg of the hydrolyzed protein carrier prepared in Preparation Example 10 and stir for 10 min.

[0089] S3. Add 3kg of thickener and 6kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0090] Example 4

[0091] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0092] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 1 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0093] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0094] Example 5

[0095] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0096] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 3 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0097] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0098] Example 6

[0099] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0100] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 4 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0101] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0102] Example 7

[0103] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0104] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 5 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0105] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0106] Example 8

[0107] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0108] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 6 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0109] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0110] Example 9

[0111] This embodiment discloses a concrete retarder, which is prepared by the following steps:

[0112] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarder component prepared in Example 7 until homogeneous.

[0113] S2. After heating to 75°C, add 25 kg of the hydrolyzed protein carrier prepared in Example 9 and stir for 10 min.

[0114] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0115] Example 10

[0116] S1. Mix 25 kg of palmitic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 2 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0117] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0118] Example 11

[0119] S1. Mix 25 kg of stearic acid as an additive and 50 kg of the organophosphorus retarding component prepared in Preparation Example 2 until homogeneous; S2. Heat to 75°C and add 25 kg of the hydrolyzed protein carrier prepared in Preparation Example 9 and stir for 10 min.

[0120] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0121] Example 12

[0122] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarder component prepared in Example 2 until homogeneous.

[0123] S2. After heating to 75°C, add 25 kg of the hydrolyzed protein carrier prepared in Example 8 and stir for 10 min.

[0124] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0125] Example 13

[0126] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarder component prepared in Example 2 until homogeneous.

[0127] S2. After heating to 75°C, add 25 kg of the hydrolyzed protein carrier prepared in Example 10 and stir for 10 min.

[0128] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0129] Comparative Example

[0130] Comparative Example 1

[0131] This comparative example discloses a concrete retarder, which is prepared by the following steps:

[0132] S1. Mix 25 kg of oleic acid as an additive and 50 kg of the organophosphorus retarder component prepared in Example 2 until homogeneous.

[0133] S2. After heating to 75℃, add 2kg of thickener and 4kg of emulsifier and stir for 20 minutes.

[0134] S3. Cool to room temperature to obtain concrete retarder.

[0135] Comparative Example 2

[0136] This comparative example discloses a concrete retarder, which is prepared by the following steps:

[0137] S1. Heat 50 kg of the organophosphorus retarder component prepared in Example 2 to 75°C;

[0138] S2. Add 25 kg of the hydrolyzed protein carrier prepared in Example 9 and stir for 10 min.

[0139] S3. Add 2kg of thickener and 4kg of emulsifier and continue stirring for 20 minutes. Cool to room temperature to obtain concrete retarder.

[0140] Comparative Example 3

[0141] This comparative example discloses a concrete retarder, which is prepared by the following steps:

[0142] S1. Heat 50 kg of the organophosphorus retarder component prepared in Example 2 to 75°C;

[0143] S2. Add 2kg of thickener and 4kg of emulsifier and stir for 20 minutes;

[0144] S3. Cool to room temperature to obtain concrete retarder.

[0145] Performance testing

[0146] Purchase commercially available ordinary Portland cement, grade P·Ⅱ52.5R, grade I fly ash, manufactured sand and gravel powder content of 4.3%, fineness modulus of 2.7, and crushed stone particle size of 5-40mm, including two particle size ranges: 20-40mm and 5-20mm. Refer to the mix proportions below.

[0147] 260 kg cement, 110 kg fly ash, 780 kg manufactured sand, 750 kg 20-40 mm crushed stone, 3250 kg 5-20 mm crushed stone, 180 kg water. The amount of retarder added is 0.05% of the total weight of the concrete.

[0148] The initial setting time, final setting time and interval time were tested and recorded in accordance with GB / T1346-2011 "Test Methods for Standard Consistency Water Requirement, Setting Time and Soundness of Cement".

[0149] Refer to GB / T 50081-2002 Standard 6 Compressive Strength Test for Mechanical Properties of Ordinary Concrete, and use standard specimens to test the compressive strength after 28 days.

[0150] Referring to GB / T 50081-2002 Test Methods for Mechanical Properties of Ordinary Concrete, Standard 10 Flexural Strength Test, the 28-day flexural strength was tested using standard specimens.

[0151] Table 1 Performance Test Data

[0152]

[0153]

[0154] As can be seen from Example 2 and Comparative Examples 1-3 and Table 1, the additives allow the organophosphorus retarding component to be diluted and then combined with the hydrolyzed protein carrier, thereby loading the organophosphorus retarding component onto the hydrolyzed protein carrier. The overall stability of the retarder is then improved by emulsifiers and thickeners. The combination of the organophosphorus retarding component and the hydrolyzed protein carrier allows the retarder to maintain its retarding ability while reducing its adverse effects on the later strength of concrete.

[0155] As can be seen from Examples 2, 6, 7, and 8 and Table 1, phosphorous acid and formaldehyde are linked to the carbon chain through the Mannich reaction, thereby enhancing the adsorption of calcium ions by diethylenetriamine and inhibiting the early hydration of cement. The carbon linking agent adds carbon chains to the central N and further extends the carbon chains through the amino grafting agent, resulting in the final product extending from the central N to three phosphorous acid-containing carbon chains of equal length. Due to the subsequent addition of carbon chains, the branches of the final product become longer, enhancing the overall toughness and stabilizing the structure of the final product. The carbon chain growth makes the final product easier to knot and adsorb calcium ions, improving the performance of the retarder. At the same time, the final product is also easier to combine with hydrolyzed protein carriers and additives, compensating for the decrease in concrete strength in the later stages caused by the addition of the retarder.

[0156] As can be seen from Examples 2, 8 and 9 and Table 1, adding sufficient formaldehyde can increase the phosphorous group on the intermediate N, but the corresponding carbon chain length is insufficient, resulting in poorer retarding performance compared to the product with three equal-length carbon chains.

[0157] As can be seen from Examples 2, 12, and 13 and Table 1, the organophosphorus retarding components prepared in different proportions have significantly different final performances, which have a significant impact on the final retarder performance.

[0158] As can be seen from Examples 2, 4, and 5 and Table 1, the organophosphorus retarding components prepared in different proportions have significantly different final performances, which have a significant impact on the final retarder performance.

[0159] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A concrete retarder, characterized in that, The raw materials include the following parts by weight: 40-60 parts of organophosphorus retarder, 20-30 parts of hydrolyzed protein carrier, 1-3 parts of thickener, 2-6 parts of emulsifier, and 20-30 parts of additive; the organophosphorus retarder is prepared from the following raw materials: diethylenetriamine, phosphorous acid, formaldehyde, carbon linking agent and amino grafting agent. The organophosphorus retarder component is prepared by the following steps: heating a diethylenetriamine solution to 100-140°C, adding phosphorous acid, formaldehyde, carbon grafting agent, amino grafting agent and sulfuric acid, stirring and mixing evenly, maintaining the reaction at 100-140°C for 14-18 hours, then cooling to room temperature and adding a 30% sodium hydroxide aqueous solution to neutralize to pH 5, thus obtaining the organophosphorus retarder component; The hydrolyzed protein carrier is prepared by the following steps: first, the protein raw material is acid-hydrolyzed to obtain acid-hydrolyzed protein mother liquor, the acid-hydrolyzed protein mother liquor is neutralized to obtain hydrolyzed protein mother liquor, and the hydrolyzed protein mother liquor is spray-dried to obtain powdered hydrolyzed protein carrier. The additive is a long-chain fatty acid.

2. The concrete retarder according to claim 1, characterized in that, The amino grafting agent is monomethylamine.

3. The concrete retarder according to claim 1, characterized in that, The carbon linking agent is glyoxal.

4. The method for preparing the concrete retarder according to any one of claims 1-3, characterized in that, The process includes the following steps: mixing the additive with the organophosphorus retarding component until homogeneous, heating to 75°C, adding the hydrolyzed protein carrier and stirring for 10 minutes, then adding the thickener and emulsifier and continuing to stir for 20 minutes, and cooling to room temperature to obtain the concrete retarder.