CN113735486B - Additive for light high-strength concrete and preparation method thereof - Google Patents
Additive for light high-strength concrete and preparation method thereof Download PDFInfo
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- CN113735486B CN113735486B CN202111065394.5A CN202111065394A CN113735486B CN 113735486 B CN113735486 B CN 113735486B CN 202111065394 A CN202111065394 A CN 202111065394A CN 113735486 B CN113735486 B CN 113735486B
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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
- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
- C04B40/0028—Aspects relating to the mixing step of the mortar preparation
- C04B40/0039—Premixtures of ingredients
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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
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
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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
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/40—Porous or lightweight materials
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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
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/20—Mortars, concrete or artificial stone characterised by specific physical values for the density
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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
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
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- Curing Cements, Concrete, And Artificial Stone (AREA)
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Abstract
The invention discloses an additive for light high-strength concrete and a preparation method thereof, wherein the raw materials for preparing a polycarboxylic acid water reducing agent are isopentenol polyoxyethylene ether: polyethylene glycol monomethyl ether acrylate: acrylic acid: 2-hydroxyethyl acrylate: chain transfer agent: reducing agent: an oxidizing agent. Then mixing and compounding 30-60% of a polycarboxylic acid water reducing agent, 2-6% of a polyacrylic acid series shrinkage reducing agent, 0.2-0.6% of an air entraining agent, 0.5-1% of a cellulose-ionic liquid complexing agent, 0.05-0.1% of a defoaming agent, 0.05-0.1% of hexadecyl trimethyl ammonium bromide and 32.3-67.25% of water to obtain the admixture for the light high-strength concrete. The invention effectively overcomes the defects of upward floating of the lightweight aggregate concrete aggregate and poor homogeneity, solves the problems of large shrinkage and poor toughness of the lightweight aggregate concrete, effectively reduces the sensitivity of the admixture to clay components in the concrete, and improves the stability of the working performance of the concrete.
Description
Technical Field
The invention relates to the technical field of additives, in particular to an additive for light high-strength concrete and a preparation method thereof.
Background
The lightweight aggregate concrete is concrete using lightweight aggregate, and has an apparent density of not more than 1950kg/m 3. The lightweight aggregate concrete has the characteristic of light weight, and with the improvement of requirements on building energy conservation and building functionality, the research and development of the high-performance lightweight aggregate concrete are rapidly developed, but further efforts are needed to research and cure the high-performance lightweight aggregate concrete.
However, since the lightweight high-strength concrete has a low density, the lightweight aggregate is easy to float upwards during the stirring process, the lightweight high-strength concrete is difficult to pump due to poor workability of the concrete, the lightweight high-strength concrete has large shrinkage due to the use of a high-cementitious material, and the lightweight high-strength concrete has large brittleness due to the high-strength concrete, and the defects are often important factors limiting the popularization and the use of the lightweight high-strength concrete.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the invention relates to an additive for light high-strength concrete and a preparation method thereof, wherein the additive adopts a mode of compounding a polycarboxylic acid water reducing agent, a polycarboxylic acid shrinkage reducing agent, a defoaming agent, an air entraining agent, a cellulose-ionic liquid complexing agent and water, so as to solve the defects of poor concrete workability, easy floating of aggregate, large concrete shrinkage, poor concrete homogeneity and toughness and the like caused by low water-cement ratio and high gel cement of the existing light ultra-high-strength concrete.
The technical scheme of the invention is as follows: a preparation method of an admixture for light high-strength concrete comprises the following steps:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, putting prenyl alcohol polyoxyethylene ether and polyethylene glycol monomethyl ether acrylate into a reaction kettle, controlling the reaction temperature to be 30-40 ℃, adding acrylic acid, acrylic acid-2-hydroxyethyl ester and an oxidant into deionized water, mixing to prepare a solution A, adding a chain transfer agent and a reducing agent into deionized water, mixing to prepare a solution B, dropwise adding A, B solution into the reaction kettle to start polymerization, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B is finished, neutralizing with a sodium hydroxide solution, and adjusting the pH to 6-7 to obtain the polycarboxylic acid water reducer;
preparation of polyacrylic acid shrinkage reducing agent: respectively preparing 50-60 mass percent aqueous solution of methacrylic acid polyglycol ether and methyl methacrylate, marking as solution C and solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature is 80 ℃, dripping the solution C and the solution D, simultaneously dripping an initiator, finishing dripping in the whole process within 2-3h, carrying out heat preservation reaction at 90 ℃ for 3-5h, cooling to room temperature after the reaction is finished, neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, and obtaining the polyacrylic acid series shrinkage reducing agent.
Mixing the prepared polycarboxylic acid water reducing agent, the polyacrylic acid shrinkage reducing agent and the defoaming agent, and then adding the air entraining agent, the cellulose-ionic liquid complexing agent, the hexadecyl trimethyl ammonium bromide and water to compound to obtain the lightweight high-strength concrete admixture.
Further, the oxidizing agent is one of potassium persulfate, sodium persulfate and ammonium persulfate, the chain transfer agent is one of 3-mercaptopropionic acid, mercaptoacetic acid and mercaptoethanol, the reducing agent is an acrylamide polymerization initiation reducing agent, and the mass concentration of sodium hydroxide is 30%.
Further, the initiator is one of tert-butyl peroxybenzoate, tert-butyl peroxypivalate, benzoyl peroxide and lauroyl peroxide, and the mass concentration of sodium hydroxide is 30%.
Further, the admixture comprises a polycarboxylic acid water reducing agent, a polyacrylic acid shrinkage reducing agent, an air entraining agent, a cellulose-ionic liquid complexing agent, a defoaming agent and water, and the mass percentage of each component is as follows: 30-60% of polycarboxylic acid water reducing agent, 2-6% of polyacrylic acid shrinkage reducing agent, 0.2-0.6% of air entraining agent, 0.5-1% of cellulose-ionic liquid complexing agent, 0.05-0.1% of defoaming agent, 0.05-0.1% of hexadecyl trimethyl ammonium bromide and 32.3-67.25% of water.
The admixture for the light high-strength concrete comprises the following raw materials in percentage by weight: prenol polyoxyethylene ether: polyethylene glycol monomethyl ether acrylate: acrylic acid: 2-hydroxyethyl acrylate: oxidizing agent: chain transfer agent: the reducing agent is 75-80:20-25:1.05-1.2:3-3.5:0.1-0.105:0.145-0.16: 0.0255-0.027.
Further, the polyacrylic acid series shrinkage reducing agent is prepared from the following raw materials in percentage by weight: methyl methacrylate: the initiator is 10-10.67:11.3-12: 0.004-0.005.
Further, the shrinkage reducing agent is a polyacrylic shrinkage reducing agent.
Further, the solid content of the polycarboxylate superplasticizer is 30-40%, and the water reduction rate is more than or equal to 30%.
Further, the air entraining agent is at least one of rosin air entraining agent, gleditsia sinensis glycoside air entraining agent and fatty alcohol sulfonate air entraining agent, and the defoaming agent is a polycarboxylate water reducing agent defoaming agent.
Further, the cellulose-ionic liquid complexing agent is a composite material of at least one of hydroxypropyl methyl cellulose, hydroxyethyl cellulose, methyl hydroxyethyl cellulose and ethyl hydroxyethyl cellulose and at least one of 1-allyl-3-methylimidazole chloride salt, 1-ethyl-3-methylimidazole chloride salt, 1-butyl-3-methylimidazole chloride salt, 1, 3-diethylimidazole diethyl phosphate salt and 4-amino-1-butylimidazole chloride salt.
The principle of the invention is as follows: the polycarboxylate superplasticizer is prepared by copolymerizing a polyether macromonomer, a comonomer and other small monomers, mainly adjusting the proportion of monomers in copolymerization reaction and reaction conditions to control the lengths of a main chain and a side chain in the preparation process, and then adjusting a molecular structure by initiating with an initiator and a chain transfer agent. The special molecular structure design makes it have good water reducing and slump retaining performance, and the polycarboxylate superplasticizer molecule is in a comb-shaped structure. When the water reducing agent is adsorbed on the surface of cement particles or the surface of a cement hydration product, a steric hindrance effect is generated, the water reducing agent can play a role in dispersing and maintaining the dispersion of the cement particles, and can also play a role in high water reducing rate and high dispersion of concrete at a low mixing amount.
The molecular structure of the polyacrylic acid series shrinkage reducing agent has special amphipathy, one end of the molecular structure is a hydrophilic group, and the other end of the molecular structure is a hydrophobic group. The main function of the cement composite material is to reduce drying shrinkage by influencing the hydration process of cement so as to change the state of hydration products and the pore structure of the cement-based composite material. The main principle is that the force on the surface of the capillary pore wall of the cement-based composite material is determined by the interaction potential energy between charged or uncharged particles, a pore solution between two capillary pore walls can change the interaction potential energy, a shrinkage reducing agent can change the stress condition of the capillary pore walls of the cement-based composite material, and molecules of the shrinkage reducing agent can be adsorbed on a gas-liquid interface of air in contact with the pore solution to reduce the capillary pore tension on the capillary pore wall, so that the shrinkage of the light high-strength concrete is effectively reduced. Meanwhile, the shrinkage reducing agent exists in the pore solution in a monomolecular mode, and a part of shrinkage reducing agent molecules are adsorbed on a solid-liquid interface of the cement-based composite material, which is in contact with the pore solution, so that the surface free energy of the cement-based composite material is reduced, and the shrinkage stress of the light high-strength concrete is correspondingly reduced.
The molecular structure of the air entraining agent consists of hydrophobic groups and hydrophilic groups. The hydrophobic group is a long carbon chain consisting of nonpolar molecules and is insoluble in water; whereas hydrophilic groups are readily soluble in water and can be negatively charged by the release of cations upon dissociation of the molecule when dissolved in water. A large amount of micro bubbles are generated in the light high-strength concrete in the stirring process, the micro bubbles are like balls, the friction resistance among aggregate particles is reduced, the problem of poor flowability of the light high-strength concrete is effectively solved, and the prepared light high-strength concrete is high in pumpability. Meanwhile, because the water is uniformly distributed on the surfaces of a large number of bubbles, the amount of water capable of freely moving is reduced, so that the water retention of the light high-strength concrete and the cohesiveness between slurry and light aggregate are improved, and the floating of the light aggregate is inhibited. And the micro bubbles can stably exist in the lightweight high-strength concrete mixture, so that the workability of the lightweight high-strength concrete mixture is improved.
The cellulose-ionic liquid complexing agent is a complex product of polymer fibers and ionic liquid, the ionic liquid is a substance which is liquid at the temperature near room temperature and consists of ions, the acting force between anions and cations is coulomb force, and the acting force between certain ions is very low, so that the melting point is below room temperature. The ionic liquid has stable physical and chemical properties, is green and environment-friendly, and has good dissolving performance on cellulose by various imidazole ionic liquids. The cellulose-ionic liquid has good stability, can be freely dissolved with water, and can regenerate cellulose under specific conditions. The cellulose-ionic liquid improves the cohesiveness between slurry and aggregate, improves the floating defect and the working performance of lightweight aggregate, improves the binding power between cement slurry and aggregate, and solves the problems of poor toughness and poor homogeneity of lightweight concrete; meanwhile, the ionic liquid is chemically inert, so that the corrosion of chloride ions to the reinforcing steel bars can be reduced.
The invention has the beneficial effects that: compared with the prior art, the cellulose-ionic liquid complexing agent adopted by the invention can effectively improve the defects of upward floating and poor homogeneity of the lightweight aggregate concrete aggregate, and solves the problems of large shrinkage and poor toughness of the lightweight aggregate concrete; the hexadecyl trimethyl ammonium bromide adopted by the invention can effectively reduce the sensitivity of the additive to clay components in concrete and improve the stability of the working performance of the concrete; the admixture for the light high-strength concrete effectively solves the problems that the light high-strength concrete in the prior art is poor in workability, and the mixture is sticky and is not easy to pump.
Detailed Description
In order to make the contents, technical solutions and advantages of the present invention more apparent, the present invention is further illustrated below with reference to specific examples, which are only used for illustrating the present invention, and the present invention is not limited to the following examples.
Example 1:
a preparation method of an admixture for light high-strength concrete comprises the following steps:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, weighing 320g of isopentenol polyoxyethylene ether, 80g of polyethylene glycol monomethyl ether acrylate and deionized water, putting the raw materials into a four-neck flask, controlling the reaction temperature to be 30-40 ℃, adding 4.8g of acrylic acid, 14g of acrylic acid-2-hydroxyethyl ester and 0.42g of oxidant into the deionized water, mixing to prepare a solution A, adding 0.64g of chain transfer agent and 0.108g of reducing agent into the deionized water, mixing to prepare a solution B, dropwise adding A, B solution into a reaction kettle to start polymerization reaction, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B, and adjusting the pH value to 6-7 to obtain the polycarboxylic acid water reducer.
Preparation of polyacrylic acid shrinkage reducing agent: adding water into 300g of polyethylene glycol methacrylate and 360g of methyl methacrylate respectively to prepare 50-60 mass percent aqueous solutions, marking as a solution C and a solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature reaches 80 ℃, dripping the solution C and the solution D, simultaneously dripping 0.15g of an initiator, finishing the whole process within 2-3h, preserving heat and reacting for 3-5h at 90 ℃, cooling to room temperature after the reaction is finished, and neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, thereby obtaining the polyacrylic acid series shrinkage reducing agent.
Compounding an additive: the additive comprises the following components in percentage by weight: 45% of a polycarboxylic acid water reducing agent; 4% of polyacrylic acid shrinkage reducing agent; 0.3 percent of air entraining agent; 0.5 percent of ethyl hydroxyethyl cellulose-1-butyl-3-methylimidazole chloride ionic liquid complexing agent; 0.05 percent of hexadecyl trimethyl ammonium bromide; 0.07 percent of defoaming agent; 49.83 percent of water.
Example 2:
a preparation method of an admixture for light high-strength concrete comprises the following steps:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, weighing 320g of isopentenol polyoxyethylene ether, 80g of polyethylene glycol monomethyl ether acrylate and deionized water, putting the raw materials into a four-neck flask, controlling the reaction temperature to be 30-40 ℃, adding 4.8g of acrylic acid, 14g of acrylic acid-2-hydroxyethyl ester and 0.42g of oxidant into the deionized water, mixing to prepare a solution A, adding 0.64g of chain transfer agent and 0.108g of reducing agent into the deionized water, mixing to prepare a solution B, dropwise adding A, B solution into a reaction kettle to start polymerization reaction, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B, and adjusting the pH value to 6-7 to obtain the polycarboxylic acid water reducer.
Preparation of polyacrylic acid shrinkage reducing agent: adding water into 300g of polyethylene glycol methacrylate and 360g of methyl methacrylate respectively to prepare 50-60 mass percent aqueous solutions, marking as a solution C and a solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature reaches 80 ℃, dripping the solution C and the solution D, simultaneously dripping 0.15g of an initiator, finishing the whole process within 2-3h, preserving heat and reacting for 3-5h at 90 ℃, cooling to room temperature after the reaction is finished, and neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, thereby obtaining the polyacrylic acid series shrinkage reducing agent.
Compounding an additive: the additive comprises the following components in percentage by weight: 45% of a polycarboxylic acid water reducing agent; 4% of polyacrylic acid shrinkage reducing agent; 0.3 percent of air entraining agent; 1% of ethyl hydroxyethyl cellulose-1-butyl-3-methylimidazole chloride ionic liquid complexing agent; 0.1% of hexadecyl trimethyl ammonium bromide; 0.07 percent of defoaming agent; 49.83 percent of water.
Example 3:
a preparation method of the admixture for the light high-strength concrete comprises the following steps:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, putting 300g of prenyl polyoxyethylene ether, 100g of polyethylene glycol monomethyl ether acrylate and deionized water into a reaction kettle, controlling the reaction temperature to be 30-40 ℃, adding 4.2g of acrylic acid, 12-2-hydroxyethyl acrylate and 0.40 g of oxygen as a catalyst into the deionized water, mixing to prepare a solution A, adding 0.58g of a chain transfer agent and 0.102 g of a reducing agent into the deionized water, mixing to prepare a solution B, dropwise adding the solution A, B into the reaction kettle to start polymerization reaction, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B is finished, and then adjusting the pH value to 6-7 to obtain the polycarboxylic acid water reducer.
Preparation of polyacrylic acid shrinkage reducing agent: adding 320g of methacrylic acid polyglycol ether and 340g of methyl methacrylate into water solutions with the mass fraction of 50-60%, marking as a solution C and a solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature reaches 80 ℃, dripping the solution C and the solution D, simultaneously dripping 0.12g of an initiator, finishing the whole process within 2-3h, preserving the temperature at 90 ℃ for reaction for 3-5h, cooling to room temperature after the reaction is finished, and neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, thereby obtaining the polyacrylic acid series shrinkage reducing agent.
Compounding an additive: the additive comprises the following components in percentage by weight: 55% of a polycarboxylic acid water reducing agent; 6% of polyacrylic acid shrinkage reducing agent; 0.5 percent of air entraining agent; 0.5 percent of methyl hydroxyethyl cellulose-1-ethyl-3-methylimidazole chloride ionic liquid complexing agent; 0.05 percent of hexadecyl trimethyl ammonium bromide; 0.1% of defoaming agent; and (5) water 37.6%.
Example 4:
a preparation method of an admixture for light high-strength concrete comprises the following steps:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, putting 300g of prenyl polyoxyethylene ether, 100g of polyethylene glycol monomethyl ether acrylate and deionized water into a reaction kettle, controlling the reaction temperature to be 30-40 ℃, adding 4.2g of acrylic acid, 12-2-hydroxyethyl acrylate and 0.40 g of oxygen as a catalyst into the deionized water, mixing to prepare a solution A, adding 0.58g of a chain transfer agent and 0.102 g of a reducing agent into the deionized water, mixing to prepare a solution B, dropwise adding the solution A, B into the reaction kettle to start polymerization reaction, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B is finished, and then adjusting the pH value to 6-7 to obtain the polycarboxylic acid water reducer.
Preparation of polyacrylic acid shrinkage reducing agent: adding 320g of methacrylic acid polyglycol ether and 340g of methyl methacrylate into water solutions with the mass fraction of 50-60%, marking as a solution C and a solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature reaches 80 ℃, dripping the solution C and the solution D, simultaneously dripping 0.12g of an initiator, finishing the whole process within 2-3h, preserving the temperature at 90 ℃ for reaction for 3-5h, cooling to room temperature after the reaction is finished, and neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, thereby obtaining the polyacrylic acid series shrinkage reducing agent.
Compounding an additive: the additive comprises the following components in percentage by weight: 55% of a polycarboxylic acid water reducing agent; 6% of polyacrylic acid shrinkage reducing agent; 0.5 percent of air entraining agent; 1% of methyl hydroxyethyl cellulose-1-ethyl-3-methylimidazole chloride ionic liquid complexing agent; 0.1% of hexadecyl trimethyl ammonium bromide; 0.1% of defoaming agent; and (5) water 37.6%.
Comparative example 1:
a preparation method of an admixture for light high-strength concrete comprises the following steps:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, weighing 320g of prenyl polyoxyethylene ether, 80g of polyethylene glycol monomethyl ether acrylate and deionized water, putting the raw materials into a four-neck flask, controlling the reaction temperature to be 30-40 ℃, adding 4.8g of acrylic acid, 14g of acrylic acid-2-hydroxyethyl ester and 0.42g of oxidant into the deionized water, mixing to prepare a solution A, adding 0.64g of chain transfer agent and 0.108g of reducing agent into the deionized water, mixing to prepare a solution B, dropwise adding A, B solution into the reaction kettle to start polymerization reaction, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B is finished, and adjusting the pH value to 6-7 to obtain the polycarboxylic acid water reducer.
Preparation of polyacrylic acid shrinkage reducing agent: adding water into 300g of polyethylene glycol methacrylate and 360g of methyl methacrylate respectively to prepare 50-60 mass percent aqueous solutions, marking as a solution C and a solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature reaches 80 ℃, dripping the solution C and the solution D, simultaneously dripping 0.15g of an initiator, finishing the whole process within 2-3h, preserving heat and reacting for 3-5h at 90 ℃, cooling to room temperature after the reaction is finished, and neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, thereby obtaining the polyacrylic acid series shrinkage reducing agent.
Compounding an additive: the additive comprises the following components in percentage by weight: 45% of a polycarboxylic acid water reducing agent; 4% of polyacrylic acid shrinkage reducing agent; 0.3 percent of air entraining agent; 1% of ethyl hydroxyethyl cellulose-1-butyl-3-methylimidazole chloride ionic liquid complexing agent; 0.1% of defoaming agent; 49.83 percent of water
Comparative example 2:
a preparation method of an admixture for light high-strength concrete comprises the following steps:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, putting 300g of prenyl polyoxyethylene ether, 100g of polyethylene glycol monomethyl ether acrylate and deionized water into a reaction kettle, controlling the reaction temperature to be 30-40 ℃, adding 4.2g of acrylic acid, 12-2-hydroxyethyl acrylate and 0.40 g of oxygen as a catalyst into the deionized water, mixing to prepare a solution A, adding 0.58g of a chain transfer agent and 0.102 g of a reducing agent into the deionized water, mixing to prepare a solution B, dropwise adding the solution A, B into the reaction kettle to start polymerization reaction, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B is finished, and then adjusting the pH value to 6-7 to obtain the polycarboxylic acid water reducer.
Preparation of polyacrylic acid shrinkage reducing agent: adding 320g of methacrylic acid polyglycol ether and 340g of methyl methacrylate into water solutions with the mass fraction of 50-60%, marking as a solution C and a solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature reaches 80 ℃, dripping the solution C and the solution D, simultaneously dripping 0.12g of an initiator, finishing the whole process within 2-3h, preserving the temperature at 90 ℃ for reaction for 3-5h, cooling to room temperature after the reaction is finished, and neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, thereby obtaining the polyacrylic acid series shrinkage reducing agent.
Compounding an additive: the additive comprises the following components in percentage by weight: 55% of a polycarboxylic acid water reducing agent; 6% of polyacrylic acid shrinkage reducing agent; 0.5 percent of air entraining agent; 0.1% of defoaming agent; and (5) water 37.6%.
The application comprises the following steps:
in order to further illustrate the excellent performance of the invention, the admixture of each example and the comparative example is applied to concrete, taking LC60 light high-strength concrete as an example, the single-use ratio and the performance of the concrete are as follows:
the concrete prepared by the application meets the technical requirements of light weight and high strength, and can meet the structure with higher bearing capacity, wherein the ex-machine expansion degree of the concrete prepared in the embodiment 1 is greater than or equal to 580mm, the slump constant is greater than or equal to 200mm, and the dry density of the concrete is less than or equal to 1400kg/m3And the 28d concrete compressive strength is 68.4MPa, and the lightweight aggregate does not float upwards. The dead weight of the structure is reduced while the bearing capacity of the structure is ensured, and the application field is wider.
As can be seen from the above table, the working performance and strength of the admixture provided by the invention are better improved when the admixture is added into the examples 1 and 2; in the concrete admixture formula of the comparative example 1, no hexadecyl trimethyl ammonium bromide component is added, and the expansion degree is reduced, the rewinding time is increased, which shows that the working performance is reduced, and the compressive strength is not obviously reduced; the formulation of the additive of comparative example 2, in which the cellulose-ionic liquid complexing agent and cetyltrimethylammonium bromide were not added, was found to have a greater reduction in the degree of expansion, a significant increase in the rewinding time, and a significant reduction in the compressive strength. The admixture prepared by the invention has good adaptability to the ultra-light concrete, can increase the working performance and the pumping performance of the admixture, and has the strength reaching the standard.
The foregoing is a further detailed description of the invention in connection with specific preferred embodiments and it is not intended to limit the invention to the specific embodiments described. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.
Claims (7)
1. The preparation method of the admixture for the light high-strength concrete is characterized by comprising the following steps of:
preparing a polycarboxylic acid water reducing agent: weighing raw materials according to a certain proportion, putting prenyl alcohol polyoxyethylene ether and polyethylene glycol monomethyl ether acrylate into a reaction kettle, controlling the reaction temperature to be 30-40 ℃, adding acrylic acid, acrylic acid-2-hydroxyethyl ester and an oxidant into deionized water, mixing to prepare a solution A, adding a chain transfer agent and a reducing agent into deionized water, mixing to prepare a solution B, dropwise adding A, B solution into the reaction kettle to start polymerization, wherein the dropwise adding time of the solution A is 2-3h, the dropwise adding time of the solution B is 3.5-4h, keeping the temperature for 1.5-2h after the dropwise adding of the solution B is finished, neutralizing with a sodium hydroxide solution, and adjusting the pH to 6-7 to obtain the polycarboxylic acid water reducer;
preparation of polyacrylic acid shrinkage reducing agent: respectively preparing 50-60 mass percent aqueous solutions of methacrylic acid polyglycol ether and methyl methacrylate, marking as a solution C and a solution D, adding metered distilled water into a four-neck flask provided with a thermometer, a speed-regulating stirrer, a reflux condensing device and a dripping device, filling nitrogen to replace air, heating and stirring in a constant-temperature oil bath until the reaction temperature is 80 ℃, dripping the solution C and the solution D, simultaneously dripping an initiator, finishing dripping in the whole process within 2-3h, carrying out heat preservation reaction at 90 ℃ for 3-5h, cooling to room temperature after the reaction is finished, neutralizing by using a sodium hydroxide solution to ensure that the pH value is 6-7, and thus obtaining the polyacrylic acid series shrinkage reducing agent;
mixing the prepared polycarboxylic acid water reducing agent, the polyacrylic acid shrinkage reducing agent and the defoaming agent, and then adding the air entraining agent, the cellulose-ionic liquid complexing agent, the hexadecyl trimethyl ammonium bromide and water for compounding to obtain the admixture for the light high-strength concrete, wherein the admixture comprises the polycarboxylic acid water reducing agent, the polyacrylic acid shrinkage reducing agent, the air entraining agent, the cellulose-ionic liquid complexing agent, the defoaming agent and the water, and the mass percentages of the components are as follows: 30-60% of a polycarboxylic acid water reducing agent, 2-6% of a polyacrylic acid shrinkage reducing agent, 0.2-0.6% of an air entraining agent, 0.5-1% of a cellulose-ionic liquid complexing agent, 0.05-0.1% of a defoaming agent, 0.05-0.1% of hexadecyl trimethyl ammonium bromide and 32.3-67.25% of water;
the cellulose-ionic liquid complexing agent is a composite material of at least one of hydroxypropyl methyl cellulose, hydroxyethyl cellulose, methyl hydroxyethyl cellulose and ethyl hydroxyethyl cellulose and at least one of 1-allyl-3-methylimidazole chloride salt, 1-ethyl-3-methylimidazole chloride salt, 1-butyl-3-methylimidazole chloride salt, 1, 3-diethylimidazole diethyl phosphate and 4-amino-1-butylimidazole chloride salt.
2. The method of claim 1, wherein the oxidizing agent is one of potassium persulfate, sodium persulfate and ammonium persulfate, the chain transfer agent is one of 3-mercaptopropionic acid, mercaptoacetic acid and mercaptoethanol, the reducing agent is an acrylamide polymerization initiation reducing agent, and the sodium hydroxide is 30% by weight.
3. The method of claim 1, wherein the initiator is one of tert-butyl peroxybenzoate, tert-butyl peroxypivalate, benzoyl peroxide and lauroyl peroxide, and the sodium hydroxide is 30% by mass.
4. The admixture prepared by the method according to claim 1, wherein the polycarboxylic acid water reducing agent comprises the following raw materials in proportion: prenol polyoxyethylene ether: polyethylene glycol monomethyl ether acrylate: acrylic acid: 2-hydroxyethyl acrylate: oxidizing agent: chain transfer agent: the reducer is 75-80:20-25:1.05-1.2:3-3.5:0.1-0.105:0.145-0.16: 0.0255-0.027.
5. The admixture prepared by the method according to claim 1, wherein the polyacrylic shrinkage-reducing agent is prepared from the following raw materials in parts by weight: methyl methacrylate: the initiator is 10-10.67:11.3-12: 0.004-0.005.
6. The admixture prepared by the method of claim 1, wherein the polycarboxylate superplasticizer has a solid content of 30-40% and a water reduction rate of not less than 30%.
7. The admixture prepared by the method according to claim 1, wherein the air-entraining agent is at least one of rosin air-entraining agent, gleditsia sinensis glycoside air-entraining agent and fatty alcohol sulfonate air-entraining agent, and the defoaming agent is polycarboxylate water reducing agent defoaming agent.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1081549A (en) * | 1996-06-21 | 1998-03-31 | Kao Corp | Concrete admixture |
| CN107652404A (en) * | 2017-09-28 | 2018-02-02 | 四川铁科新型建材有限公司 | A kind of normal temperature synthesizing polyester polyether type of poly carboxylic acid and preparation method thereof |
| CN108892412A (en) * | 2018-07-24 | 2018-11-27 | 成都建工预筑科技有限公司 | Lightweight aggregate concrete special additive and its preparation process |
| CN108947314A (en) * | 2018-08-21 | 2018-12-07 | 河北鑫合生物化工有限公司 | A kind of concrete with water-retaining property, pumping, workability, adaptability |
| CN110746136A (en) * | 2019-09-27 | 2020-02-04 | 中建商品混凝土有限公司 | Shrinkage-reducing thickening type alkali-free liquid accelerator and preparation method and application thereof |
| CN110938176A (en) * | 2018-09-25 | 2020-03-31 | 中建材中岩科技有限公司 | Super-long slump loss resistant cement-based polycarboxylate superplasticizer mother liquor and application thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108675716A (en) * | 2018-05-29 | 2018-10-19 | 吴远怀 | A kind of PVA-ECC high-tenacity fibers cement-base composite material and preparation method thereof |
| CN110143791A (en) * | 2019-05-27 | 2019-08-20 | 合肥雅克丽新型建材有限公司 | A kind of preparation process of high-strength concrete |
-
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- 2021-09-12 CN CN202111065394.5A patent/CN113735486B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1081549A (en) * | 1996-06-21 | 1998-03-31 | Kao Corp | Concrete admixture |
| CN107652404A (en) * | 2017-09-28 | 2018-02-02 | 四川铁科新型建材有限公司 | A kind of normal temperature synthesizing polyester polyether type of poly carboxylic acid and preparation method thereof |
| CN108892412A (en) * | 2018-07-24 | 2018-11-27 | 成都建工预筑科技有限公司 | Lightweight aggregate concrete special additive and its preparation process |
| CN108947314A (en) * | 2018-08-21 | 2018-12-07 | 河北鑫合生物化工有限公司 | A kind of concrete with water-retaining property, pumping, workability, adaptability |
| CN110938176A (en) * | 2018-09-25 | 2020-03-31 | 中建材中岩科技有限公司 | Super-long slump loss resistant cement-based polycarboxylate superplasticizer mother liquor and application thereof |
| CN110746136A (en) * | 2019-09-27 | 2020-02-04 | 中建商品混凝土有限公司 | Shrinkage-reducing thickening type alkali-free liquid accelerator and preparation method and application thereof |
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