CN112920342A - Early-strength polycarboxylate superplasticizer and preparation method thereof - Google Patents
Early-strength polycarboxylate superplasticizer and preparation method thereof Download PDFInfo
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- CN112920342A CN112920342A CN202110152669.2A CN202110152669A CN112920342A CN 112920342 A CN112920342 A CN 112920342A CN 202110152669 A CN202110152669 A CN 202110152669A CN 112920342 A CN112920342 A CN 112920342A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F283/00—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
- C08F283/06—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polyethers, polyoxymethylenes or polyacetals
- C08F283/065—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polyethers, polyoxymethylenes or polyacetals on to unsaturated polyethers, polyoxymethylenes or polyacetals
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/26—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- C04B24/2688—Copolymers containing at least three different monomers
- C04B24/2694—Copolymers containing at least three different monomers containing polyether side chains
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/30—Water reducers, plasticisers, air-entrainers, flow improvers
- C04B2103/302—Water reducers
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- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
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- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention belongs to the technical field of concrete admixtures, and particularly relates to an early-strength polycarboxylate superplasticizer and a preparation method thereof. The water reducing agent comprises the following raw materials: modified orange peel residue, 1-tetradecene, acrylic acid, methacrylic acid, 30% hydrogen peroxide, triethanolamine, acrylonitrile, maleic anhydride, prenol polyoxyethylene ether, methyl allyl polyoxyethylene ether, vitamin C and deionized water. According to the invention, the orange peel residue is used for modification, so that the concrete water reducing agent is prepared, and can cooperate with the polycarboxylic acid water reducing agent, and after the concrete water reducing agent is added into concrete, the retraction of a concrete member, the generation of cracks and the like can be effectively inhibited; the water reducing agent prepared by the invention can improve the early strength, meet the requirements of high-strength concrete and the like, and meanwhile, the water reducing rate is high, the addition amount is low, the dispersion stability is good, bleeding and layering are avoided, and the strength of the concrete is not influenced.
Description
Technical Field
The invention belongs to the technical field of concrete admixtures, and particularly relates to an early-strength polycarboxylate superplasticizer and a preparation method thereof.
Background
The polycarboxylic acid water reducing agent is a novel high-efficiency water reducing agent, has the advantages of low mixing amount, high water reducing rate, good slump retentivity, small shrinkage rate and good adaptability to cement and mixing, and is widely applied to the engineering fields of municipal administration, railways, highways and the like at present.
Precast concrete requires a good early strength development rate of concrete, thereby satisfying the demand for strength under low temperature conditions. The high-strength concrete pipe pile is a concrete product with wide popularization range in recent years, and has the advantages of high strength grade, large bearing capacity, good impact resistance and the like, but at present, the addition of the water reducing agent influences the hydration process of cement, prolongs the setting time of concrete, is not beneficial to the development of early strength, cannot meet the production requirement of jujube-strength concrete, and the early-strength water reducing agent easily causes the shrinkage of a concrete structure and influences the performance of the concrete structure; therefore, the precast concrete and the high-strength pipe pile concrete need a water reducing agent which has early strength and good cohesiveness but does not influence the quality of the concrete.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides an early-strength polycarboxylate superplasticizer which can effectively increase the early strength of concrete, and has the advantages of low yield, high water reducing rate, good stability of the concrete after use, no bleeding and the like.
The invention also provides a preparation method of the early-strength polycarboxylate superplasticizer.
The technical scheme adopted by the invention for realizing the purpose is as follows:
the invention provides an early-strength polycarboxylate superplasticizer which comprises the following raw materials in parts by weight: 5-8 parts of modified orange peel residue, 3-5 parts of 1-tetradecene, 25-30 parts of acrylic acid, 5-8 parts of methacrylic acid, 2-3 parts of 30% hydrogen peroxide, 10-15 parts of triethanolamine, 10-12 parts of acrylonitrile, 0.2-0.5 part of maleic anhydride, 180 parts of isopentenol polyoxyethylene ether, 200 parts of methyl allyl polyoxyethylene ether, 1-1.2 parts of vitamin C and 380 parts of deionized water.
The modified orange peel residue used in the invention is prepared by the following method: crushing orange peel, grinding into slurry to obtain orange peel residue, adding the orange peel residue into a formaldehyde aqueous solution, heating to 25 ℃, stirring for reaction for 3-3.5h, slowly dropwise adding ammonia water, slowly heating to 75-80 ℃, keeping the temperature and stirring for 2h, cooling to room temperature, and adjusting the pH value to be neutral.
Further, the mass ratio of the formaldehyde to the orange peel residues is 0.05-0.08: 1; the mass concentration of the formaldehyde aqueous solution is 35%.
Further, the mass ratio of the ammonia water to the formaldehyde is 1: 1.
the invention also provides a preparation method of the early-strength polycarboxylate superplasticizer, which comprises the following steps:
(1) uniformly mixing 1-tetradecene and acrylonitrile, adding maleic anhydride, uniformly stirring, keeping a reaction system at 0 ℃, slowly dropwise adding concentrated sulfuric acid, continuously stirring for 30min after dropwise adding is finished, slowly heating to room temperature, reacting for 18-20h, filtering after the reaction is finished, washing a product, and drying for later use;
(2) adding methacrylic acid into a reaction kettle, heating to 80-85 ℃, then adding triethanolamine, slowly dropwise adding p-toluenesulfonic acid, reacting for 5-8h under heat preservation, and adding acrylic acid to obtain a solution A;
(3) mixing prenyl alcohol polyoxyethylene ether, methyl allyl polyoxyethylene ether, hydrogen peroxide and the product obtained in the step (1), adding 2/3 parts by weight of deionized water, and uniformly stirring to form a solution B;
(4) dispersing the modified orange peel residue and the vitamin C into the residual deionized water to obtain a solution C;
(5) and slowly adding the solution A into the solution B at room temperature for 3 hours, simultaneously adding the solution C dropwise for 3 hours, continuously stirring for 40min after the dropwise addition is finished, then adjusting the pH value to 7, and stirring for 30 min.
Further, in the step (1), the mass ratio of the added concentrated sulfuric acid to 1-tetradecene is 0.03: 1.
further, in the step (2), the mass ratio of the p-toluenesulfonic acid to the methacrylic acid is 0.06: 1.
the invention has the beneficial effects that:
(1) according to the invention, the orange peel slag is used for modification, so that the concrete water reducing agent is prepared, on one hand, abundant vitamins contained in the orange peel slag promote the oxidation-reduction reaction, and meanwhile, the waste recycling is realized, the cost of the polycarboxylic acid water reducing agent is reduced, and meanwhile, the components contained in the orange peel slag can cooperate with the polycarboxylic acid water reducing agent, and after the orange peel slag is added into concrete, the retraction of concrete members, the generation of cracks and the like can be effectively inhibited;
(2) the water reducing agent prepared by the invention can improve the early strength, meet the requirements of high-strength concrete and the like, and meanwhile, the water reducing rate is high, the addition amount is low, the dispersion stability is good, bleeding and layering are avoided, and the strength of the concrete is not influenced.
Detailed Description
The technical solution of the present invention is further described in time and by the following specific examples.
Example 1
An early strength type polycarboxylate superplasticizer comprises the following components in percentage by weight: 5 parts of modified orange peel residue, 5 parts of 1-tetradecene, 28 parts of acrylic acid, 7 parts of methacrylic acid, 3 parts of 30% hydrogen peroxide, 12 parts of triethanolamine, 12 parts of acrylonitrile, 0.5 part of maleic anhydride, 180 parts of prenyl polyoxyethylene ether, 180 parts of methallyl polyoxyethylene ether, 1 parts of vitamin C and 380 parts of deionized water.
The modified orange peel residue is prepared by the following method: crushing 10 parts of orange peel, grinding the orange peel into pulp to obtain orange peel residue, adding 0.5-0.8 part of formaldehyde aqueous solution into the orange peel residue, heating to 25 ℃, stirring for reacting for 3.5h, slowly dropwise adding 0.5-0.8 part of ammonia water, slowly heating to 75-80 ℃, keeping the temperature and stirring for 2h, cooling to room temperature, and adjusting the pH value to be neutral.
The preparation method of the polycarboxylic acid water reducing agent comprises the following steps:
(1) uniformly mixing 1-tetradecene and acrylonitrile, adding maleic anhydride, uniformly stirring, keeping a reaction system at 0 ℃, then slowly dropwise adding 0.03 part of concentrated sulfuric acid, continuously stirring for 30min after dropwise adding is finished, then slowly heating to room temperature, reacting for 20h, filtering after the reaction is finished, washing a product, and drying for later use;
(2) adding methacrylic acid into a reaction kettle, heating to 80-85 ℃, then adding triethanolamine, slowly dropwise adding 0.42 part of p-toluenesulfonic acid, keeping the temperature for reaction for 6 hours, and then adding acrylic acid to obtain a solution A;
(3) mixing prenyl alcohol polyoxyethylene ether, methyl allyl polyoxyethylene ether, hydrogen peroxide and the product obtained in the step (1), adding 2/3 parts by weight of deionized water, and uniformly stirring to form a solution B;
(4) dispersing the modified orange peel residue and the vitamin C into the residual deionized water to obtain a solution C;
(5) and slowly adding the solution A into the solution B at room temperature for 3 hours, simultaneously adding the solution C dropwise for 3 hours, continuously stirring for 40min after the dropwise addition is finished, then adjusting the pH value to 7, and stirring for 30 min.
Example 2
An early strength type polycarboxylate superplasticizer comprises the following components in percentage by weight: 7 parts of modified orange peel residue, 3 parts of 1-tetradecene, 30 parts of acrylic acid, 5 parts of methacrylic acid, 3 parts of 30% hydrogen peroxide, 10 parts of triethanolamine, 11 parts of acrylonitrile, 0.3 part of maleic anhydride, 150 parts of prenyl polyoxyethylene ether, 180 parts of methyl allyl polyoxyethylene ether, 1.2 parts of vitamin C and 380 parts of deionized water.
The preparation method is basically the same as that of example 1.
Example 3
An early strength type polycarboxylate superplasticizer comprises the following components in percentage by weight: 8 parts of modified orange peel residue, 5 parts of 1-tetradecene, 25 parts of acrylic acid, 8 parts of methacrylic acid, 3 parts of 30% hydrogen peroxide, 12 parts of triethanolamine, 10 parts of acrylonitrile, 0.5 part of maleic anhydride, 160 parts of prenyl polyoxyethylene ether, 200 parts of methallyl polyoxyethylene ether, 1 part of vitamin C and 380 parts of deionized water.
The preparation method is the same as example 1.
Comparative example 1
An early strength type polycarboxylate superplasticizer comprises the following components in percentage by weight: 5 parts of 1-tetradecene, 28 parts of acrylic acid, 7 parts of methacrylic acid, 3 parts of 30% hydrogen peroxide, 12 parts of triethanolamine, 12 parts of acrylonitrile, 0.5 part of maleic anhydride, 180 parts of prenol polyoxyethylene ether, 180 parts of methallyl polyoxyethylene ether, 1 parts of vitamin C and 380 parts of deionized water.
The preparation method is basically the same as example 1, except that the modified orange peel residue is not added to the solution C.
Comparative example 2
An early strength type polycarboxylate superplasticizer comprises the following components in percentage by weight: 5 parts of modified orange peel residue, 28 parts of acrylic acid, 7 parts of methacrylic acid, 3 parts of 30% hydrogen peroxide, 12 parts of triethanolamine, 0.5 part of maleic anhydride, 180 parts of prenyl alcohol polyoxyethylene ether, 180 parts of methallyl polyoxyethylene ether, 1 parts of vitamin C and 380 parts of deionized water.
The preparation method comprises the following steps:
(1) adding methacrylic acid into a reaction kettle, heating to 80-85 ℃, then adding triethanolamine, slowly dropwise adding 0.42 part of p-toluenesulfonic acid, keeping the temperature for reaction for 6 hours, and then adding acrylic acid to obtain a solution A;
(3) mixing prenyl alcohol polyoxyethylene ether, methyl allyl polyoxyethylene ether, hydrogen peroxide and maleic anhydride, adding 2/3 parts by weight of deionized water, and uniformly stirring to form a solution B;
(4) dispersing the modified orange peel residue and the vitamin C into the residual deionized water to obtain a solution C;
(5) and slowly adding the solution A into the solution B at room temperature for 3 hours, simultaneously adding the solution C dropwise for 3 hours, continuously stirring for 40min after the dropwise addition is finished, then adjusting the pH value to 7, and stirring for 30 min.
Effects of the embodiment
Firstly, the early strength type polycarboxylate superplasticizer prepared in the embodiment 1-3 and the comparative example 1-2 is mixed in an amount of 0.35% according to GB/T8077-; specific results are shown in table 1.
TABLE 1
As can be seen from Table 2, the early strength type polycarboxylate water reducer prepared by the invention can meet the concrete with early strength requirement, and does not generate bleeding, while the concrete systems prepared by comparative examples 1 and 2 generate bleeding.
Secondly, the compressive strength of the early strength type polycarboxylate superplasticizer prepared in the examples 1-3 and the comparative examples 1-2 is detected according to the method provided by GB8076-2008, and the specific results are shown in Table 2.
TABLE 2
Claims (7)
1. The early-strength polycarboxylate superplasticizer is characterized by comprising the following raw materials in parts by weight: 5-8 parts of modified orange peel residue, 3-5 parts of 1-tetradecene, 25-30 parts of acrylic acid, 5-8 parts of methacrylic acid, 2-3 parts of 30% hydrogen peroxide, 10-15 parts of triethanolamine, 10-12 parts of acrylonitrile, 0.2-0.5 part of maleic anhydride, 180 parts of isopentenol polyoxyethylene ether, 200 parts of methyl allyl polyoxyethylene ether, 1-1.2 parts of vitamin C and 380 parts of deionized water.
2. The early strength type polycarboxylate superplasticizer according to claim 1, wherein the modified orange peel residue is prepared by the following method: crushing orange peel, grinding into slurry to obtain orange peel residue, adding the orange peel residue into a formaldehyde aqueous solution, heating to 25 ℃, stirring for reaction for 3-3.5h, slowly dropwise adding ammonia water, slowly heating to 75-80 ℃, keeping the temperature and stirring for 2h, cooling to room temperature, and adjusting the pH value to be neutral.
3. The early strength type polycarboxylate superplasticizer according to claim 2, wherein the mass ratio of the formaldehyde to the orange peel residue is 0.05-0.08: 1; the mass concentration of the formaldehyde aqueous solution is 35%.
4. The early strength type polycarboxylate superplasticizer according to claim 2 or 3, wherein the mass ratio of ammonia water to formaldehyde is 1: 1.
5. the preparation method of the early strength type polycarboxylate superplasticizer according to any one of claims 1 to 4, characterized by comprising the following steps:
(1) uniformly mixing 1-tetradecene and acrylonitrile, adding maleic anhydride, uniformly stirring, keeping a reaction system at 0 ℃, slowly dropwise adding concentrated sulfuric acid, continuously stirring for 30min after dropwise adding is finished, slowly heating to room temperature, reacting for 18-20h, filtering after the reaction is finished, washing a product, and drying for later use;
(2) adding methacrylic acid into a reaction kettle, heating to 80-85 ℃, then adding triethanolamine, slowly dropwise adding p-toluenesulfonic acid, reacting for 5-8h under heat preservation, and adding acrylic acid to obtain a solution A;
(3) mixing prenyl alcohol polyoxyethylene ether, methyl allyl polyoxyethylene ether, hydrogen peroxide and the product obtained in the step (1), adding 2/3 parts by weight of deionized water, and uniformly stirring to form a solution B;
(4) dispersing the modified orange peel residue and the vitamin C into the residual deionized water to obtain a solution C;
(5) and slowly adding the solution A into the solution B at room temperature for 3 hours, simultaneously adding the solution C dropwise for 3 hours, continuously stirring for 40min after the dropwise addition is finished, then adjusting the pH value to 7, and stirring for 30 min.
6. The preparation method according to claim 5, wherein in the step (1), the addition amount of the concentrated sulfuric acid is 0.03: 1.
7. the production method according to claim 5, wherein in the step (2), the mass ratio of the p-toluenesulfonic acid to the methacrylic acid is 0.06: 1.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113372087A (en) * | 2021-07-19 | 2021-09-10 | 深圳市东大洋水泥制品有限公司 | Early-strength high-impermeability concrete and preparation method thereof |
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| CN104371075A (en) * | 2014-11-22 | 2015-02-25 | 萧县鑫固混凝土外加剂有限公司 | Method for preparing polycarboxylate superplasticizer synthesized at room temperature |
| CN109627394A (en) * | 2018-11-30 | 2019-04-16 | 陕西科技大学 | A kind of polycarboxylate concrete dehydragent and preparation method thereof being adapted to Machine-made Sand |
| CN111995281A (en) * | 2020-09-03 | 2020-11-27 | 安徽理工大学 | Preparation method and application of cement additive based on waste orange peel |
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- 2021-02-04 CN CN202110152669.2A patent/CN112920342A/en active Pending
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| CN109627394A (en) * | 2018-11-30 | 2019-04-16 | 陕西科技大学 | A kind of polycarboxylate concrete dehydragent and preparation method thereof being adapted to Machine-made Sand |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113372087A (en) * | 2021-07-19 | 2021-09-10 | 深圳市东大洋水泥制品有限公司 | Early-strength high-impermeability concrete and preparation method thereof |
| CN113372087B (en) * | 2021-07-19 | 2022-06-24 | 深圳市东大洋水泥制品有限公司 | Early-strength high-impermeability concrete and preparation method thereof |
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Application publication date: 20210608 |