Totally-synthesized ultrahigh-water-reducing type polycarboxylic acid water reducer and preparation method thereof

Abstract

The invention relates to the technical field of building materials, in particular to a fully-synthetic ultrahigh-water-reducing type polycarboxylic acid water reducer and a preparation method thereof. The fully-synthetic ultrahigh-water-reducing type polycarboxylic acid water reducer is prepared from the following raw materials in parts by weight: 20 to 30 parts of modified methyl allyl polyoxyethylene ether, 10 to 15 parts of acrylic acid, 8 to 12 parts of methacryloyloxyethyl trimethyl ammonium chloride, 3 to 5 parts of functional additive, 2 to 4 parts of chain transfer agent, 4 to 7 parts of hydrogen peroxide, 1 to 5 parts of composite reducing agent and 40 to 50 parts of deionized water, the fully-synthesized ultrahigh-water-reducing type polycarboxylic acid water reducer prepared by the invention not only has a better water reducing effect, but also has the advantages of high early strength, no loss of later strength, energy conservation, environmental protection, good stability and the like, and the quality of the fully-synthesized ultrahigh-water-reducing type polycarboxylic acid water reducer is effectively ensured.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, in particular to a fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent and a preparation method thereof. Background Art

[0002] Concrete admixtures are one of the key factors in the development of modern concrete technology. With the trend of high-rise and large-span construction projects and the increasing requirements for concrete durability, high-efficiency water reducers have emerged. In actual engineering applications, polycarboxylic acid-based water reducers have some defects, such as rapid slump loss, which requires frequent addition of admixtures to maintain its fluidity during concrete construction, and low compressive strength, which increases construction difficulty and cost.

[0003] Based on this, the present invention provides a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer and a preparation method thereof to solve the above-mentioned technical problems. Summary of the invention

[0004] The object of the present invention is to provide a fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent and a preparation method thereof. The prepared fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent not only has a good water-reducing effect, but also has the advantages of high early strength, no loss of late strength, energy saving and environmental protection, good stability, etc., which effectively guarantees its quality.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The first aspect of the present invention provides a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer, which is composed of the following raw materials in parts by weight: 20 to 30 parts of modified methyl allyl polyoxyethylene ether, 10 to 15 parts of acrylic acid, 8 to 12 parts of methacryloyloxyethyl trimethyl ammonium chloride, 3 to 5 parts of functional additives, 2 to 4 parts of chain transfer agents, 4 to 7 parts of hydrogen peroxide, 1 to 5 parts of composite reducing agents and 40 to 50 parts of deionized water.

[0007] The present invention is further configured as follows: the preparation process of the modified methyl allyl polyoxyethylene ether is as follows:

[0008] Fully dissolve methyl allyl polyoxyethylene ether at 60-65°C, and then add 0.8-1.2% of the mass of methyl allyl polyoxyethylene ether of boron trifluoride ethyl ether thereto under nitrogen atmosphere;

[0009] The temperature is raised to 90-98°C, and 2.2-2.6% of γ-carboxypropyltrimethoxysilane by weight of methyl allyl polyoxyethylene ether is added thereto at 120-160 r / min. The mixture is heat-treated for 12-14 hours, and vacuum distilled to obtain modified methyl allyl polyoxyethylene ether.

[0010] The present invention is further configured as follows: the preparation process of the functional additive is as follows:

[0011] The nano-silicon dioxide is placed in ethanol for ultrasonic treatment at a solid-liquid ratio of 0.02-0.12 g / mL for 20-30 minutes, γ-carboxylpropyltrimethoxysilane is added thereto at a mass percentage of 0.2-1.2% of the nano-silicon dioxide, and the mixture is treated at 500-600 r / min for 10-30 minutes. After filtration, the mixture is placed at 110-120° C. for 2-4 hours to obtain a base material;

[0012] The base material is placed in N,N-dimethylformamide at a solid-liquid ratio of 0.02-0.08 g / mL and ultrasonically treated for 20-30 minutes, N,N-dicyclohexylcarbodiimide and 4-dimethylaminopyridine are added thereto, and the base material is treated at 50-60 r / min for 5-10 minutes to obtain a functional additive.

[0013] The present invention is further configured as follows: the addition amount of the N,N-dicyclohexylcarbodiimide is 3.1-4.2% of the mass of the base material, and the addition amount of the 4-dimethylaminopyridine is 2.2-5.2% of the mass of the base material.

[0014] The present invention is further configured as follows: the composite reducing agent is formed by mixing sodium formaldehyde sulfoxylate and sodium ascorbate in a mass ratio of 4 to 6:1.

[0015] The present invention is further configured as follows: the chain transfer agent is selected from any one of mercaptoethanol and 3-mercaptopropionic acid.

[0016] The second aspect of the present invention: also provides a method for preparing the above-mentioned fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent, comprising the following steps:

[0017] Step 1, accurately weigh modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agent, hydrogen peroxide, composite reducing agent and deionized water for use;

[0018] Step 2: Add modified methyl allyl polyoxyethylene ether, hydrogen peroxide and deionized water into a mixing device for mixing and stirring for 5 to 8 minutes, and heat to 50 to 55° C. after mixing evenly, and then dropwise add a dropwise liquid composed of a composite reducing agent, a chain transfer agent, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride and deionized water at 55 to 65 r / min. After the dropwise addition is completed, continue stirring for 60 to 70 minutes;

[0019] Step 3: Add functional additives and continue stirring for 6 to 8 hours to obtain a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer.

[0020] The present invention is further configured as follows: in step 2, the dripping time is 180 to 200 minutes.

[0021] The present invention is further configured as follows: in step three, the stirring speed is 100-220 r / min, and the stirring temperature is 26-30°C.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] In the present invention, modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agents, hydrogen peroxide, composite reducing agents and deionized water are used as raw materials to prepare a fully synthetic ultra-high water-reducing polycarboxylic acid water-reducing agent. The fully synthetic ultra-high water-reducing polycarboxylic acid water-reducing agent prepared by the present invention not only has a good water-reducing effect, but also has the advantages of high early strength, no loss of late strength, energy saving and environmental protection, good stability, etc., which effectively guarantees its quality. The fully synthetic ultra-high water-reducing polycarboxylic acid water-reducing agent and its preparation method provided by the present invention have a broader market prospect and are more suitable for promotion. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1

[0026] The present embodiment provides a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer, which is composed of the following raw materials in parts by weight: 20 parts of modified methyl allyl polyoxyethylene ether, 10 parts of acrylic acid, 8 parts of methacryloyloxyethyl trimethyl ammonium chloride, 3 parts of functional additives, 2 parts of chain transfer agents, 4 parts of hydrogen peroxide, 1 part of a composite reducing agent and 40 parts of deionized water.

[0027] Wherein, the preparation process of modified methyl allyl polyoxyethylene ether is as follows:

[0028] Fully dissolve methyl allyl polyoxyethylene ether at 60°C, and then add 0.8% by mass of methyl allyl polyoxyethylene ether of boron trifluoride ethyl ether thereto under nitrogen atmosphere;

[0029] The temperature was raised to 90° C., and γ-carboxypropyltrimethoxysilane (2.2% by mass of methyl allyl polyoxyethylene ether) was added thereto at 120 r / min. The mixture was kept warm for 12 hours and distilled under reduced pressure to obtain modified methyl allyl polyoxyethylene ether.

[0030] In this embodiment, it should be noted that methyl allyl polyoxyethylene ether was purchased from Nanjing Bote New Materials Co., Ltd.

[0031] The preparation process of functional additives is as follows:

[0032] Nano-silica was placed in ethanol for ultrasonic treatment at a solid-liquid ratio of 0.02 g / mL for 20 minutes, γ-carboxypropyltrimethoxysilane (0.2% by mass of the nano-silica) was added thereto, and the mixture was treated at 500 r / min for 10 minutes. After filtration, the mixture was placed at 110° C. for 2 hours to obtain a base material;

[0033] The base material was placed in N,N-dimethylformamide at a solid-liquid ratio of 0.02 g / mL and ultrasonically treated for 20 minutes. N,N-dicyclohexylcarbodiimide and 4-dimethylaminopyridine were added thereto and treated at 50 r / min for 5 minutes to obtain a functional additive.

[0034] Furthermore, the addition amount of N,N-dicyclohexylcarbodiimide is 3.1% of the mass of the base material, and the addition amount of 4-dimethylaminopyridine is 2.2% of the mass of the base material.

[0035] In this embodiment, it should be noted that the nano-silicon dioxide was purchased from Hubei Huifu Nanomaterials Co., Ltd.

[0036] The composite reducing agent is prepared by mixing sodium formaldehyde sulfoxylate and sodium ascorbate in a mass ratio of 4:1.

[0037] Mercaptoethanol was selected as the chain transfer agent.

[0038] In addition, this embodiment also provides a method for preparing the above-mentioned fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent, comprising the following steps:

[0039] Step 1: Accurately weigh modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agent, hydrogen peroxide, composite reducing agent and deionized water for later use.

[0040] Step 2: Add modified methyl allyl polyoxyethylene ether, hydrogen peroxide and deionized water into a mixing device and mix and stir for 5 minutes. After mixing evenly, heat to 50°C, and then add a droplet of a composite reducing agent, a chain transfer agent, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride and deionized water at 55r / min. After the addition is completed, continue stirring for 60 to 70 minutes.

[0041] Furthermore, the dropping time is 180 min.

[0042] Step 3: Add functional additives and continue stirring for 6 hours to obtain a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer.

[0043] Furthermore, the stirring speed is 100 r / min, and the stirring temperature is 26°C.

[0044] Example 2

[0045] The preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer provided in this embodiment is basically the same as that in Example 1, except that: the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are different; the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are as follows:

[0046] A fully synthetic super-high water-reducing polycarboxylic acid-based water reducer is composed of the following raw materials in parts by weight: 2 parts of modified methyl allyl polyoxyethylene ether, 11 parts of acrylic acid, 9 parts of methacryloyloxyethyl trimethyl ammonium chloride, 4 parts of functional additives, 3 parts of chain transfer agents, 5 parts of hydrogen peroxide, 2 parts of composite reducing agents and 42 parts of deionized water.

[0047] Wherein, the preparation process of modified methyl allyl polyoxyethylene ether is as follows:

[0048] Fully dissolve methyl allyl polyoxyethylene ether at 61°C, and then add 0.9% of the mass of methyl allyl polyoxyethylene ether of boron trifluoride ethyl ether in a nitrogen atmosphere;

[0049] The temperature was raised to 92° C., and γ-carboxypropyltrimethoxysilane (2.3% by mass of methyl allyl polyoxyethylene ether) was added thereto at 130 r / min. The mixture was kept warm for 13 hours and distilled under reduced pressure to obtain modified methyl allyl polyoxyethylene ether.

[0050] In this embodiment, it should be noted that methyl allyl polyoxyethylene ether was purchased from Nanjing Bote New Materials Co., Ltd.

[0051] The preparation process of functional additives is as follows:

[0052] The nano-silica was placed in ethanol and ultrasonically treated for 22 minutes at a solid-liquid ratio of 0.04 g / mL, γ-carboxypropyltrimethoxysilane (0.3% by mass of the nano-silica) was added thereto, and the mixture was treated at 510 r / min for 12 minutes. After filtration, the mixture was placed at 112° C. and treated for 3 hours to obtain a base material;

[0053] The base material was placed in N,N-dimethylformamide at a solid-liquid ratio of 0.03 g / mL and ultrasonically treated for 22 minutes. N,N-dicyclohexylcarbodiimide and 4-dimethylaminopyridine were added thereto and treated at 52 r / min for 6 minutes to obtain a functional additive.

[0054] Furthermore, the added amount of N,N-dicyclohexylcarbodiimide is 3.2% of the mass of the base material, and the added amount of 4-dimethylaminopyridine is 2.3% of the mass of the base material.

[0055] In this embodiment, it should be noted that the nano-silicon dioxide was purchased from Hubei Huifu Nanomaterials Co., Ltd.

[0056] The composite reducing agent is prepared by mixing sodium formaldehyde sulfoxylate and sodium ascorbate in a mass ratio of 5:1.

[0057] The chain transfer agent is 3-mercaptopropionic acid.

[0058] In addition, this embodiment also provides a method for preparing the above-mentioned fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent, comprising the following steps:

[0059] Step 1: Accurately weigh modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agent, hydrogen peroxide, composite reducing agent and deionized water for later use.

[0060] Step 2: Add modified methyl allyl polyoxyethylene ether, hydrogen peroxide and deionized water into a mixing equipment and mix and stir for 6 minutes. After mixing evenly, heat to 51°C, and then add a droplet of a composite reducing agent, a chain transfer agent, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride and deionized water at 57 r / min. After the addition is completed, continue stirring for 62 minutes.

[0061] Furthermore, the dropping time was 185 min.

[0062] Step 3: Add functional additives and continue stirring for 7 hours to obtain a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer.

[0063] Furthermore, the stirring speed is 110 r / min, and the stirring temperature is 27°C.

[0064] Example 3

[0065] The preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer provided in this embodiment is basically the same as that in Example 1, except that: the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are different; the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are as follows:

[0066] A fully synthetic super-high water-reducing polycarboxylic acid-based water reducer is composed of the following raw materials in parts by weight: 25 parts of modified methallyl polyoxyethylene ether, 12 parts of acrylic acid, 10 parts of methacryloyloxyethyl trimethylammonium chloride, 4 parts of functional additives, 3 parts of chain transfer agents, 5 parts of hydrogen peroxide, 3 parts of composite reducing agents and 45 parts of deionized water.

[0067] Wherein, the preparation process of modified methyl allyl polyoxyethylene ether is as follows:

[0068] Fully dissolve methyl allyl polyoxyethylene ether at 62°C, and then add 1% by mass of methyl allyl polyoxyethylene ether of boron trifluoride ethyl ether in a nitrogen atmosphere;

[0069] The temperature was raised to 94°C, and γ-carboxypropyltrimethoxysilane (2.4% by mass of methyl allyl polyoxyethylene ether) was added thereto at 140 r / min. The mixture was kept warm for 13 hours and distilled under reduced pressure to obtain modified methyl allyl polyoxyethylene ether.

[0070] In this embodiment, it should be noted that methyl allyl polyoxyethylene ether was purchased from Nanjing Bote New Materials Co., Ltd.

[0071] The preparation process of functional additives is as follows:

[0072] Nano-silica was placed in ethanol and ultrasonically treated for 25 minutes at a solid-liquid ratio of 0.07 g / mL, γ-carboxypropyltrimethoxysilane (0.7% by mass of the nano-silica) was added thereto, and the mixture was treated at 550 r / min for 20 minutes. After filtration, the mixture was placed at 115° C. and treated for 3 hours to obtain a base material;

[0073] The base material was placed in N,N-dimethylformamide at a solid-liquid ratio of 0.05 g / mL and ultrasonically treated for 25 minutes. N,N-dicyclohexylcarbodiimide and 4-dimethylaminopyridine were added thereto, and the base material was treated at 55 r / min for 7 minutes to obtain a functional additive.

[0074] Furthermore, the addition amount of N,N-dicyclohexylcarbodiimide is 3.6% of the mass of the base material, and the addition amount of 4-dimethylaminopyridine is 3.7% of the mass of the base material.

[0075] In this embodiment, it should be noted that the nano-silicon dioxide was purchased from Hubei Huifu Nanomaterials Co., Ltd.

[0076] The composite reducing agent is prepared by mixing sodium formaldehyde sulfoxylate and sodium ascorbate in a mass ratio of 5:1.

[0077] Mercaptoethanol was selected as the chain transfer agent.

[0078] In addition, this embodiment also provides a method for preparing the above-mentioned fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent, comprising the following steps:

[0079] Step 1: Accurately weigh modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agent, hydrogen peroxide, composite reducing agent and deionized water for later use.

[0080] Step 2: Add modified methyl allyl polyoxyethylene ether, hydrogen peroxide and deionized water into a mixing equipment and mix and stir for 6 minutes. After mixing evenly, heat to 52°C, and then add a droplet of a composite reducing agent, a chain transfer agent, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride and deionized water at 60r / min. After the addition is completed, continue stirring for 65 minutes.

[0081] Furthermore, the dropping time was 190 min.

[0082] Step 3: Add functional additives and continue stirring for 7 hours to obtain a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer.

[0083] Furthermore, the stirring speed is 160 r / min, and the stirring temperature is 28°C.

[0084] Example 4

[0085] The preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer provided in this embodiment is basically the same as that in Example 1, except that: the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are different; the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are as follows:

[0086] A fully synthetic super-high water-reducing polycarboxylic acid-based water reducer is composed of the following raw materials in parts by weight: 8 parts of modified methyl allyl polyoxyethylene ether, 14 parts of acrylic acid, 11 parts of methacryloyloxyethyl trimethyl ammonium chloride, 4 parts of functional additives, 3 parts of chain transfer agents, 6 parts of hydrogen peroxide, 4 parts of composite reducing agents and 48 parts of deionized water.

[0087] Wherein, the preparation process of modified methyl allyl polyoxyethylene ether is as follows:

[0088] Fully dissolve methyl allyl polyoxyethylene ether at 64°C, and then add 1.1% of the mass of methyl allyl polyoxyethylene ether of boron trifluoride ethyl ether thereto under nitrogen atmosphere;

[0089] The temperature was raised to 97°C, and γ-carboxypropyltrimethoxysilane (2.5% by mass of methyl allyl polyoxyethylene ether) was added thereto at 150 r / min. The mixture was kept warm for 13 hours and distilled under reduced pressure to obtain modified methyl allyl polyoxyethylene ether.

[0090] In this embodiment, it should be noted that methyl allyl polyoxyethylene ether was purchased from Nanjing Bote New Materials Co., Ltd.

[0091] The preparation process of functional additives is as follows:

[0092] The nano-silica was placed in ethanol and ultrasonically treated for 28 minutes at a solid-liquid ratio of 0.11 g / mL, γ-carboxypropyltrimethoxysilane (1.1% by mass of the nano-silica) was added thereto, and the mixture was treated at 580 r / min for 28 minutes. After filtration, the mixture was placed at 118° C. and treated for 3 hours to obtain a base material;

[0093] The base material was placed in N,N-dimethylformamide at a solid-liquid ratio of 0.07 g / mL and ultrasonically treated for 28 minutes. N,N-dicyclohexylcarbodiimide and 4-dimethylaminopyridine were added thereto and treated at 58 r / min for 8 minutes to obtain a functional additive.

[0094] Furthermore, the added amount of N,N-dicyclohexylcarbodiimide is 4.1% of the mass of the base material, and the added amount of 4-dimethylaminopyridine is 5.1% of the mass of the base material.

[0095] In this embodiment, it should be noted that the nano-silicon dioxide was purchased from Hubei Huifu Nanomaterials Co., Ltd.

[0096] The composite reducing agent is prepared by mixing sodium formaldehyde sulfoxylate and sodium ascorbate in a mass ratio of 5:1.

[0097] Mercaptoethanol was selected as the chain transfer agent.

[0098] In addition, this embodiment also provides a method for preparing the above-mentioned fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent, comprising the following steps:

[0099] Step 1: Accurately weigh modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agent, hydrogen peroxide, composite reducing agent and deionized water for later use.

[0100] Step 2: Add modified methyl allyl polyoxyethylene ether, hydrogen peroxide and deionized water into a mixing equipment and mix and stir for 78 minutes. After mixing evenly, heat to 54°C, and then add a droplet of a composite reducing agent, a chain transfer agent, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride and deionized water at 64r / min. After the addition is completed, continue stirring for 68 minutes.

[0101] Furthermore, the dropping time was 195 min.

[0102] Step 3: Add functional additives and continue stirring for 7 hours to obtain a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer.

[0103] Furthermore, the stirring speed is 210 r / min, and the stirring temperature is 29°C.

[0104] Example 5

[0105] The preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer provided in this embodiment is basically the same as that in Example 1, except that: the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are different; the specific raw material composition and the specific preparation method of the fully synthetic ultra-high water-reducing polycarboxylic acid water reducer in this embodiment are as follows:

[0106] A fully synthetic super-high water-reducing polycarboxylic acid-based water reducer is composed of the following raw materials in parts by weight: 30 parts of modified methallyl polyoxyethylene ether, 15 parts of acrylic acid, 12 parts of methacryloyloxyethyl trimethylammonium chloride, 5 parts of functional additives, 4 parts of chain transfer agents, 7 parts of hydrogen peroxide, 5 parts of composite reducing agents and 50 parts of deionized water.

[0107] Wherein, the preparation process of modified methyl allyl polyoxyethylene ether is as follows:

[0108] Fully dissolve methyl allyl polyoxyethylene ether at 65°C, and then add 1.2% of the mass of methyl allyl polyoxyethylene ether of boron trifluoride ether thereto under nitrogen atmosphere;

[0109] The temperature was raised to 98°C, and γ-carboxypropyltrimethoxysilane (2.6% by mass of methyl allyl polyoxyethylene ether) was added thereto at 160 r / min. The mixture was kept warm for 14 hours and distilled under reduced pressure to obtain modified methyl allyl polyoxyethylene ether.

[0110] In this embodiment, it should be noted that methyl allyl polyoxyethylene ether was purchased from Nanjing Bote New Materials Co., Ltd.

[0111] The preparation process of functional additives is as follows:

[0112] The nano-silica was placed in ethanol for ultrasonic treatment at a solid-liquid ratio of 0.12 g / mL for 30 minutes, γ-carboxypropyltrimethoxysilane (1.2% by mass of the nano-silica) was added thereto, and the mixture was treated at 600 r / min for 30 minutes. After filtration, the mixture was placed at 120° C. for 4 hours to obtain a base material;

[0113] The base material was placed in N,N-dimethylformamide at a solid-liquid ratio of 0.08 g / mL and ultrasonically treated for 30 minutes, N,N-dicyclohexylcarbodiimide and 4-dimethylaminopyridine were added thereto, and the base material was treated at 60 r / min for 5 to 10 minutes to obtain a functional additive.

[0114] Furthermore, the added amount of N,N-dicyclohexylcarbodiimide is 4.2% of the mass of the base material, and the added amount of 4-dimethylaminopyridine is 5.2% of the mass of the base material.

[0115] In this embodiment, it should be noted that the nano-silicon dioxide was purchased from Hubei Huifu Nanomaterials Co., Ltd.

[0116] The composite reducing agent is prepared by mixing sodium formaldehyde sulfoxylate and sodium ascorbate in a mass ratio of 6:1.

[0117] Mercaptoethanol was selected as the chain transfer agent.

[0118] In addition, this embodiment also provides a method for preparing the above-mentioned fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent, comprising the following steps:

[0119] Step 1: Accurately weigh modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agent, hydrogen peroxide, composite reducing agent and deionized water for later use.

[0120] Step 2: Add modified methyl allyl polyoxyethylene ether, hydrogen peroxide and deionized water into a mixing equipment and mix and stir for 8 minutes. After mixing evenly, heat to 55°C, and then add a droplet of a composite reducing agent, a chain transfer agent, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride and deionized water at 65r / min. After the addition is completed, continue stirring for 70 minutes.

[0121] Furthermore, the dropping time is 200 min.

[0122] Step 3: Add functional additives and continue stirring for 8 hours to obtain a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer.

[0123] Furthermore, the stirring speed is 220 r / min, and the stirring temperature is 30°C.

[0124] Comparative Example 1: The difference from Example 1 is that in this example, an equal amount of methyl allyl polyoxyethylene ether is used instead of modified methyl allyl polyoxyethylene ether.

[0125] Comparative Example 2: The difference from Example 1 is that this example does not contain a functional additive.

[0126] Comparative Example 3: The difference from Example 1 is that an equal amount of nano-silicon dioxide is used to replace the base material in this example.

[0127] Performance test: The fully synthetic super water-reducing polycarboxylic acid water-reducing agent samples provided in Examples 1 to 5 and Comparative Examples 1 to 3 are marked as Examples 1 to 5 and Comparative Examples 1 to 3, respectively; and the relevant properties of the fully synthetic super water-reducing polycarboxylic acid water-reducing agent provided in Examples 1 to 5 and Comparative Examples 1 to 3 are tested as follows:

[0128] The cement used in this experiment is Onoda 42.5R, and the fly ash is Huaneng secondary ash. The mud content is 2.3%, and the fineness modulus is 2.5. The mud content is 0.5%, and the stone has a particle size of 5-20. The mixing time is 100 seconds, and the vibration time is 15 seconds. The mix ratio is cement: fly ash: mineral powder: sand: stone: water = 185: 80: 80: 1000: 840: 155, and the dosage of the fully synthetic super-high water-reducing polycarboxylic acid water-reducing agent is 0.2%.

[0129] The obtained test data are recorded in Table 1 below:

[0130] Table 1 Performance test results of each group of water reducers

[0131]

[0132] By comparing and analyzing the relevant data in Table 1, it can be seen that the fully synthetic ultra-high water-reducing polycarboxylic acid water-reducing agent prepared by the present invention not only has a good water-reducing effect, but also has the advantages of high early strength, no loss of late strength, energy saving and environmental protection, good stability, etc., which effectively guarantees its quality. This shows that the fully synthetic ultra-high water-reducing polycarboxylic acid water-reducing agent and its preparation method provided by the present invention have a broader market prospect and are more suitable for promotion.

[0133] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0134] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A fully synthetic super water-reducing polycarboxylic acid water reducer, characterized in that: The invention is composed of the following raw materials in parts by weight: 20 to 30 parts of modified methyl allyl polyoxyethylene ether, 10 to 15 parts of acrylic acid, 8 to 12 parts of methacryloyloxyethyl trimethyl ammonium chloride, 3 to 5 parts of functional additives, 2 to 4 parts of chain transfer agents, 4 to 7 parts of hydrogen peroxide, 1 to 5 parts of composite reducing agents and 40 to 50 parts of deionized water.

2. A fully synthetic super water-reducing polycarboxylic acid water reducer according to claim 1, characterized in that: The preparation process of the modified methyl allyl polyoxyethylene ether is as follows: Fully dissolve methyl allyl polyoxyethylene ether at 60-65°C, and then add 0.8-1.2% of the mass of methyl allyl polyoxyethylene ether of boron trifluoride ethyl ether thereto under nitrogen atmosphere; The temperature is raised to 90-98°C, and 2.2-2.6% of γ-carboxypropyltrimethoxysilane by weight of methyl allyl polyoxyethylene ether is added thereto at 120-160 r / min. The mixture is heat-treated for 12-14 hours, and vacuum distilled to obtain modified methyl allyl polyoxyethylene ether.

3. A fully synthetic super water-reducing polycarboxylic acid water reducer according to claim 1, characterized in that: The preparation process of the functional additive is as follows: The nano-silicon dioxide is placed in ethanol for ultrasonic treatment at a solid-liquid ratio of 0.02-0.12 g / mL for 20-30 minutes, γ-carboxylpropyltrimethoxysilane is added thereto at a mass percentage of 0.2-1.2% of the nano-silicon dioxide, and the mixture is treated at 500-600 r / min for 10-30 minutes. After filtration, the mixture is placed at 110-120° C. for 2-4 hours to obtain a base material; The base material is placed in N,N-dimethylformamide at a solid-liquid ratio of 0.02-0.08 g / mL and ultrasonically treated for 20-30 minutes, N,N-dicyclohexylcarbodiimide and 4-dimethylaminopyridine are added thereto, and the base material is treated at 50-60 r / min for 5-10 minutes to obtain a functional additive.

4. A fully synthetic super water-reducing polycarboxylic acid water reducer according to claim 3, characterized in that: The added amount of the N,N-dicyclohexylcarbodiimide is 3.1-4.2% of the mass of the base material, and the added amount of the 4-dimethylaminopyridine is 2.2-5.2% of the mass of the base material.

5. A fully synthetic super water-reducing polycarboxylic acid water reducer according to claim 1, characterized in that: The composite reducing agent is prepared by mixing sodium formaldehyde sulfoxylate and sodium ascorbate in a mass ratio of 4 to 6:

1.

6. A fully synthetic super water-reducing polycarboxylic acid water reducer according to claim 1, characterized in that: The chain transfer agent is selected from any one of mercaptoethanol and 3-mercaptopropionic acid.

7. A method for preparing a fully synthetic ultra-high water-reducing polycarboxylic acid-based water-reducing agent according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1, accurately weigh modified methyl allyl polyoxyethylene ether, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride, functional additives, chain transfer agent, hydrogen peroxide, composite reducing agent and deionized water for use; Step 2: Add modified methyl allyl polyoxyethylene ether, hydrogen peroxide and deionized water into a mixing device for mixing and stirring for 5 to 8 minutes, and heat to 50 to 55° C. after mixing evenly, and then dropwise add a dropwise liquid composed of a composite reducing agent, a chain transfer agent, acrylic acid, methacryloyloxyethyl trimethyl ammonium chloride and deionized water at 55 to 65 r / min. After the dropwise addition is completed, continue stirring for 60 to 70 minutes; Step 3: Add functional additives and continue stirring for 6 to 8 hours to obtain a fully synthetic ultra-high water-reducing polycarboxylic acid-based water reducer.

8. The method for preparing a fully synthetic ultra-high water-reducing polycarboxylic acid water-reducing agent according to claim 7, characterized in that: In step 2, the dropping time is 180 to 200 minutes.

9. The method for preparing a fully synthetic ultra-high water-reducing polycarboxylic acid water-reducing agent according to claim 7, characterized in that: In step three, the stirring speed is 100-220 r / min, and the stirring temperature is 26-30°C.

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