CN111423147A

CN111423147A - Concrete glue reducing agent and preparation method thereof

Info

Publication number: CN111423147A
Application number: CN202010460584.6A
Authority: CN
Inventors: 杨海华; 孙成伟
Original assignee: Nantong Rhett Building Materials Co ltd
Current assignee: Nantong Rhett Building Materials Co ltd
Priority date: 2020-05-26
Filing date: 2020-05-26
Publication date: 2020-07-17

Abstract

The invention relates to the technical field of concrete preparation, in particular to a concrete gel reducing agent and a preparation method thereof. The preparation raw materials of the gel reducing agent comprise, by weight, 20-30 parts of substituted organic amine and 40-60 parts of water; the substituent of the substituted organic amine is selected from one or more of ester group, sulfonic group, carboxylic group and hydroxyl. The invention provides a glue reducing agent which can be used in concrete, can obviously reduce the using amount of cement, avoids the reduction of the strength and the slump of the concrete, effectively reduces the time loss of the concrete, improves the concrete opposite sex, can be used together with a water reducing agent and the like, saves the cost while ensuring the physical properties of the concrete, and accords with JC/T2469-2018.

Description

Concrete glue reducing agent and preparation method thereof

Technical Field

The invention relates to the technical field of concrete preparation, in particular to a concrete gel reducing agent and a preparation method thereof.

Background

Under the conventional atmospheric environment and production, stirring and maintenance conditions, 5-15% of cement in the concrete is not completely hydrated, only plays a role of filling, cannot be effectively dispersed to generate hydration reaction, and cannot effectively exert the effect of all cement. On the other hand, because different series of water reducing agents have different absorption and dispersion action mechanisms on cement particles, the water reducing agents are difficult to play a role in dispersing the cement particles in concrete and improving the bonding performance of a cement paste body and an aggregate interface after being added to a certain degree, and the economical efficiency required by the concrete is difficult to effectively exert.

The concrete glue reducing agent is also called concrete synergist/concrete synergist, is a novel concrete additive different from a concrete water reducing agent, and is mainly characterized in that under the same concrete strength grade, the glue reducing agent with the effective mixing amount of 0.05-0.06% is added, so that the cement using amount can be reduced by 5% -15%, the mechanical property of the concrete can be ensured not to be reduced, and meanwhile, the workability and the volume stability of the concrete are improved to different degrees.

At present, the components of the gel reducing agent mainly comprise alcohol amine compounds, and the types of the alcohol amine compounds are single, so that the preparation method of the gel reducing agent is further expanded, and the gel reducing agent has important significance on the expanded development of the gel reducing agent. And the molecular weight of the main functional unit of the glue reducing agent is generally small, the glue reducing agent basically does not have steric hindrance, and the glue reducing and dispersing capacity is limited. The glue reducer and the water reducer have larger difference in molecular structure types, and have a certain matching problem, which seriously restricts the application and development of the glue reducer.

Disclosure of Invention

In order to solve the problems, the invention provides a concrete gel reducing agent in a first aspect, wherein the preparation raw materials of the gel reducing agent comprise, by weight, 20-30 parts of substituted organic amine and 40-60 parts of water; the substituent of the substituted organic amine is selected from one or more of ester group, sulfonic group, carboxylic group and hydroxyl.

As a preferable technical scheme of the invention, the substituted organic amine with the substituent being hydroxyl is selected from one or more of triethanolamine, triisopropanolamine, N-butyl ethanolamine, methyldiethanolamine, N-diisopropylethanolamine and tert-butyl ethanolamine.

As a preferable technical solution of the present invention, the raw material for preparing the gel reducing agent further comprises polycarboxylic acid, and the monomer of the polycarboxylic acid comprises two or more of acrylic acid, hydroxyethyl acrylate, methacrylic acid, 2-acetaminoacrylic acid, dimethylaminoethyl acrylate, acrylamide, hydroxymethyl acrylamide, diacetone acrylamide, and ethyl acetoacetate methacrylate.

As a preferable technical scheme of the invention, the monomer of the polycarboxylic acid comprises acrylic acid, methacrylic acid, hydroxyethyl methacrylate and dimethylaminoethyl acrylate, and the weight ratio of the acrylic acid to the methacrylic acid is 1: (1-2): (0.2-0.3): (0.5 to 1).

In a preferred embodiment of the present invention, the polycarboxylic acid is a modified polycarboxylic acid, and the modifier of the modified polycarboxylic acid is one selected from polyoxyethylene sorbitan monooleate, and ethoxylated glycerol monooleate.

As a preferred technical solution of the present invention, the weight ratio of the monomer to the modifier is 1: (0.05-0.1).

As a preferable technical scheme of the invention, the number average molecular weight of the modifier is 400-800.

As a preferable technical scheme of the present invention, the weight ratio of the substituted organic amine to the polycarboxylic acid is 1: (1-2).

As a preferable technical scheme, the preparation raw material of the gel reducing agent also comprises an auxiliary agent, wherein the auxiliary agent comprises one or more of a penetrating agent, a defoaming agent, a dispersing agent, a wetting agent, a thickening agent and a sulfate promoter.

The second aspect of the invention provides a preparation method of the concrete gel reducing agent, which comprises the following steps:

and mixing the preparation raw materials of the gel reducing agent to obtain the gel reducing agent.

Compared with the prior art, the invention has the following beneficial effects: the invention provides a glue reducing agent which can be used in concrete, can obviously reduce the using amount of cement, avoids the reduction of the strength and the slump of the concrete, effectively reduces the time loss of the concrete, improves the concrete opposite sex, can be used together with a water reducing agent and the like, saves the cost while ensuring the physical properties of the concrete, and accords with JC/T2469-2018.

Detailed Description

The disclosure may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.

The term "prepared from …" as used herein is synonymous with "comprising". The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

The conjunction "consisting of …" excludes any unspecified elements, steps or components. If used in a claim, the phrase is intended to claim as closed, meaning that it does not contain materials other than those described, except for the conventional impurities associated therewith. When the phrase "consisting of …" appears in a clause of the subject matter of the claims rather than immediately after the subject matter, it defines only the elements described in the clause; other elements are not excluded from the claims as a whole.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. "optional" or "any" means that the subsequently described event or events may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

Approximating language, as used herein throughout the specification and claims, is intended to modify a quantity, such that the invention is not limited to the specific quantity, but includes portions that are literally received for modification without substantial change in the basic function to which the invention is related. Accordingly, the use of "about" to modify a numerical value means that the invention is not limited to the precise value. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. In the present description and claims, range limitations may be combined and/or interchanged, including all sub-ranges contained therein if not otherwise stated.

In addition, the indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the stated number clearly indicates that the singular form is intended.

The present invention is illustrated by the following specific embodiments, but is not limited to the specific examples given below.

The first aspect of the invention provides a concrete gel reducing agent, which comprises 20-30 parts of substituted organic amine and 40-60 parts of water by weight.

In a preferred embodiment, the preparation raw material of the gel reducer comprises 25 parts of substituted organic amine and 50 parts of water in parts by weight.

Substituted organic amines

In one embodiment, the substituent of the substituted organic amine of the present invention is selected from one or more of an ester group, a sulfonic acid group, a carboxylic acid group, and a hydroxyl group.

Examples of the substituted organic amine having an ester group and a sulfonic acid group as substituents include, but are not limited to, triethylesteramine trisulfonate, disulfonic-ethanoldiethylesteramine.

Examples of the substituted organic amine whose substituent is a hydroxyl group include, but are not limited to, triethanolamine, triisopropanolamine, N-butyl ethanolamine, methyldiethanolamine, N-diisopropylethanolamine, tert-butyl ethanolamine.

Preferably, the substituted organic amine comprises a substituted organic amine with an ester group and a sulfonic group and a substituted organic amine with a hydroxyl substituent, and the weight ratio of the substituted organic amine to the substituted organic amine is 1: (2-3); further, the substituted organic amine comprises ester group and sulfonic group substituted organic amine and hydroxyl substituted organic amine, and the weight ratio of the substituted organic amine to the hydroxyl substituted organic amine is 1: 2.

in the mixing process of concrete, the water reducing agent cannot be dispersed due to the existence of small adhered particles, and can be dispersed with the small micro-aggregate particles by adding the small-molecule substituted organic amine, and the small micro-aggregate particles are dispersed by electrostatic repulsion, so that the interface performance between cement paste and aggregate is improved, the cement can fully play a role, and the workability and stability of the concrete can be ensured under the condition of reducing the cement using amount; the applicant finds that the organic amine with amino ester group and hydroxyl group is favorable for exciting hydration of the iron aluminate which is difficult to hydrate, improving the dispersion of cement, coal ash powder and the like, and improving the wrapping property of sand, stone and the like.

However, the stability of mechanical properties such as strength of concrete is limited due to the small structure of organic amine and the large structural difference with water reducing agents such as lignosulfonic acid water reducing agents, and the slump is rapidly reduced while the hydration degree of cement is promoted for organic amine such as triethanolamine, which is not beneficial to anisotropy and processability.

In one embodiment, the raw materials for preparing the size reducer of the present invention further comprise polycarboxylic acid.

Polycarboxylic acids

In one embodiment, the monomers of the polycarboxylic acid of the present invention include two or more of acrylic acid, hydroxyethyl acrylate, methacrylic acid, 2-acetamidoacrylic acid, dimethylaminoethyl acrylate, acrylamide, methylolacrylamide, diacetone acrylamide, and ethyl acetoacetate methacrylate.

Preferably, the monomer of the polycarboxylic acid comprises acrylic acid, methacrylic acid, hydroxyethyl methacrylate and dimethylaminoethyl acrylate, and the weight ratio of the monomer to the monomer is 1: (1-2): (0.2-0.3): (0.5 to 1); further, the monomer of the polycarboxylic acid comprises acrylic acid, methacrylic acid, hydroxyethyl methacrylate and dimethylaminoethyl acrylate, and the weight ratio of the acrylic acid to the hydroxyethyl methacrylate to the dimethylaminoethyl acrylate is 1: 1.5: 0.2: 0.6.

the method of preparing the polycarboxylic acid of the present invention is a method well known in the art, and in one embodiment, the method of preparing the polycarboxylic acid comprises the steps of: and dropwise adding the monomer, the initiator and the chain transfer agent into a solvent, reacting at 40-50 ℃, and adjusting the pH to 6-7 to obtain the polycarboxylic acid.

Examples of initiators include, but are not limited to, persulfates, benzoyl peroxide, azobisisobutyronitrile, sodium dithionite, sodium formaldehyde sulfoxylate, ascorbic acid, sodium bisulfite, sodium metabisulfite, sodium hypophosphite, dextrose monohydrate, maltodextrin. In a preferred embodiment, the initiator of the present invention is 1 to 3 wt% of the monomer.

Examples of chain transfer agents include, but are not limited to, 3-mercaptopropionic acid, mercaptoacetic acid, mercaptoethanol, isopropanol. In one embodiment, the chain transfer agent of the present invention is present in an amount of 0.3 to 0.6 wt% based on the weight of the monomers.

Examples of solvents include, but are not limited to, water.

The applicant finds that by adding polycarboxylic acid, such as acrylic acid, methacrylic acid and dimethylaminoethyl acrylate as monomers, the synthesized polycarboxylic acid has a strong polar carboxyl and ammonia structure, can promote adsorption to the surface of fine particles, further disperse small particles due to the action of larger bit groups and charge repulsion, delay hydration reaction due to the high-molecular chain structure of strong electron-withdrawing in the polycarboxylic acid and certain cross-linking, and high adsorption on the surface of the particles and water, and further prevent partial water from directly contacting the particles, control the progress of hydration along with the hydrolysis of the partially cross-linked network of the polycarboxylic acid and the formation of hydrogen bonds, and slow down the rate of slump reduction while improving the dispersibility and anisotropy of the particles.

The glue reducing agent and the water reducing agent prepared by the applicant by adopting a polycarboxylic acid structure, such as a lignosulfonic acid water reducing agent, have good compatibility, and the molecular weight of polycarboxylic acid is controlled to be smaller than that of the lignosulfonic acid water reducing agent by adopting a chain transfer agent, so that competition with the lignosulfonic acid water reducing agent is avoided, and the dispersibility of the water reducing agent is improved. And the applicant finds that when the polycarboxylic acid containing hydroxyl, ammonia structure and carboxyl is adopted, the polycarboxylic acid has good compatibility with the water reducing agent, and the influence on the anisotropy, strength and the like due to poor compatibility is avoided.

However, the applicant found that when a polycarboxylic acid is added, the initial strength of the resulting gel reducing agent is reduced as compared with the case where no gel reducing agent is added, and this is probably because the initial strength is reduced due to the introduction of fine bubbles into the polycarboxylic acid.

More preferably, the polycarboxylic acid of the present invention is a modified polycarboxylic acid.

Examples of the modifier for modifying the polycarboxylic acid include, but are not limited to, polyoxyethylene sorbitan monooleate, such as Tween 81 (number average molecular weight: 648, hydroxyl value: 134 to 150mgKOH/g), Tween 80 (number average molecular weight: 1309.63, hydroxyl value: 65 to 80mgKOH/g) from Guangdong Hua chemical Co., Ltd.; sorbitan monooleate, such as span 80 (number average molecular weight of 428.59, hydroxyl value of 193-210 mgKOH/g) from Guangdong Runhua chemical Co., Ltd; one of ethoxylated glycerol monooleate.

Further preferably, the modifier of the modified polycarboxylic acid is selected from one of polyoxyethylene sorbitan monooleate, sorbitan monooleate and ethoxylated glycerol monooleate; further, the modifier is polyoxyethylene sorbitan monooleate.

Still more preferably, the weight ratio of the monomers and the modifier according to the invention is 1: (0.05-0.1); further, the weight ratio of the monomer and the modifier is 1: 0.08.

in a preferred embodiment, the number average molecular weight of the modifier is 400 to 800; further, the number average molecular weight of the modifier is 600-700.

The number average molecular weight is the molecular weight statistically averaged by the number of molecules.

In a more preferred embodiment, the modifier of the invention has a hydroxyl value of 100 to 150 mgKOH/g; furthermore, the hydroxyl value of the modifier is 130-150 mgKOH/g.

The hydroxyl value is the number of milligrams of potassium hydroxide (KOH) corresponding to the hydroxyl groups in 1g of the sample, expressed as mgKOH/g.

In a further preferred embodiment, the process for producing a modified polycarboxylic acid according to the present invention comprises the steps of:

and dropwise adding the monomer, the modifier, the initiator and the chain transfer agent into a solvent, reacting at 40-50 ℃, and adjusting the pH to 6-7 to obtain the modified polycarboxylic acid.

The applicant has found that by introducing the side chain of polyoxyethylene sorbitan monooleate when using a modified polycarboxylic acid such as polyoxyethylene sorbitan monooleate as a modifying agent, the multi-branched polyoxyethylene sorbitan monooleate structure promotes the formation of an adsorption film of polycarboxylic acid and organic amine on small particles when used in concrete, reduces the surface energy of the particles, reduces the aggregation between the fine particles, reduces the possibility of the closure of cracks between the particles, promotes the growth of cracks, improves the dispersion and pulverization of the small particles, forms the formation of the inter-particle grading, provides more smaller particles, promotes the formation of gel, and thus improves the early strength. And by adopting the side chain structure of polyhydroxy and branched chains, bubbles in the concrete can be refined, the reduction of strength is avoided, and the coating of cement and the like on sand, stone and the like is facilitated, and the improvement of the property is realized.

However, the applicant found that when a modifier having a relatively large molecular weight is used, improvement of strength and slump is adversely affected, probably because long side chains may entangle with a plurality of particles, affecting dispersion and gradation of small particles, thereby affecting properties such as strength. In addition, the applicant finds that although the addition of the modified polycarboxylic acid is beneficial to the formation of gel in the initial stage and the improvement of strength, the gel reducing agent obtained by the addition of the modified polycarboxylic acid is easy to damage the structure of the gel in the early stage along with the gradual improvement of hydration in the later stage, so that the strength in the later stage is reduced compared with the strength in the later stage without adding or reducing the gel, and the carboxylic acid is modified, and a multi-branched modifier side chain is added, so that the viscosity is higher, and the increase of the strength in the later stage and the optimization of the anisotropy are not.

In a still further preferred embodiment, the weight ratio of substituted organic amine to polycarboxylic acid according to the invention is 1: (1-2); further, the weight ratio of the substituted organic amine to the polycarboxylic acid is 1: 1.5.

the applicant finds that by using the substituted organic amine and the polycarboxylic acid, such as modified polycarboxylic acid, the small-molecular organic amine can promote the dispersion of the polycarboxylic acid with larger viscosity, and the small particles are adsorbed and reconstructed by the electrostatic and bit group effects of the substituted organic amine and the polycarboxylic acid, so that the dispersion of an early gel structure is promoted while the small particles are aggregated, more water molecules participate in the hydration process, the hydration degree of a later stage is improved, and the strength of the later stage is enhanced. The applicant finds that the proportion of the small-molecular organic amine and the large-molecular polycarboxylic acid needs to be ensured, the functions of the glue reducing agent for activating the cement and promoting hydration and fluidity can be fully exerted, and the physical properties of the concrete, such as strength, collapse protection and the like, are improved under the combined action of the glue reducing agent and a water reducing agent, such as a lignosulfonic acid water reducing agent.

In one embodiment, the preparation raw material of the gel reducer of the invention further comprises an auxiliary agent.

Auxiliary agent

The auxiliary is not specifically limited in the present invention, and may be an auxiliary well known in the art. In one embodiment, the adjuvants of the present invention include one or more of a penetrant, a defoamer, a dispersant, a wetting agent, a thickener, a sulfate promoter.

Examples of penetrants include, but are not limited to, sulfated castor oil, sodium alkyl benzene sulfonate, sodium alkyl sulfate, sodium secondary alkyl sulfonate, sodium secondary alkyl sulfate, sodium alkyl naphthalene sulfonate, sodium sulfamate. In a preferred embodiment, the penetrating agent accounts for 0 to 0.5 wt% of the gel reducing agent.

Examples of defoamers include, but are not limited to, organosilicone defoamers, polyether modified silicone defoamers. In a preferred embodiment, the defoaming agent accounts for 0 to 0.5 wt% of the glue reducer.

Examples of the dispersing agent include, but are not limited to, α -sodium alkenyl sulfonate, polyvinyl alcohol ether, polyethylene glycol monooleate, stearyl alcohol polyoxyethylene ether, polyoxyethylene lauryl ether, polyoxyethylene sorbitan tristearate, nonylphenol polyoxyethylene ether and castor oil polyoxyethylene ether, in a preferred embodiment, the dispersing agent of the present invention accounts for 0-0.5 wt% of the weight of the degelling agent.

Examples of wetting agents include, but are not limited to, polydimethylsiloxane, polymethylphenylsiloxane, polydiethylsiloxane, polyethylene wax, oxidized polyethylene wax, chlorinated paraffin, stearic acid amide, oleic acid amide, N-ethylene bis-stearic acid amide, erucic acid amide, N-butyl stearate, glycerol tri-stearate, calcium stearate, sodium stearate. In a preferred embodiment, the wetting agent of the present invention is 0 to 0.5 wt% of the size reducer.

As examples of the thickening agent, β -cyclodextrin, dispersible latex powder and cellulose can be mentioned, and in a preferred embodiment, the thickening agent is 0-0.5 wt% of the size reducer.

Examples of sulfate promoters include, but are not limited to, sodium oxalate, potassium chromate, potassium dichromate, sodium chromate, sodium dichromate, sodium silicate, potassium silicate. In a preferred embodiment, the sulfate promoter of the present invention is 0 to 0.5 wt% of the size reducer.

Examples

The present invention will be specifically described below by way of examples. It should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the insubstantial modifications and adaptations of the present invention by those skilled in the art based on the above disclosure are still within the scope of the present invention.

Example 1

The embodiment provides a glue reducing agent, and the glue reducing agent is prepared from 20 parts of substituted organic amine, 30 parts of polycarboxylic acid and 50 parts of water in parts by weight; the substituted organic amine is triethanolamine trisulfonate and triethanolamine, and the weight ratio is 1: 2; the polycarboxylic acid is modified polycarboxylic acid, and the preparation method of the modified polycarboxylic acid comprises the following steps: dropwise adding the monomer, the modifier, the initiator and the chain transfer agent into a solvent, reacting at 45 ℃, and adjusting the pH to 6.5 to obtain the modified polycarboxylic acid; the monomer is acrylic acid, methacrylic acid, hydroxyethyl methacrylate and dimethylaminoethyl acrylate, and the weight ratio is 1: 1.5: 0.2: 0.6, the initiator is sodium persulfate which accounts for 2 wt% of the monomers, the chain transfer agent is 3-mercaptopropionic acid which accounts for 0.5 wt% of the monomers, the solvent is water, the modifier is polyoxyethylene sorbitan monooleate, and the weight ratio of the monomers to the modifier is 1: 0.08.

the polyoxyethylene sorbitan monooleate is purchased from tween 81 of Guangdong Hua chemical Co.

The embodiment also provides a preparation method of the concrete gel reducing agent, which comprises the following steps:

Example 2

The embodiment provides a glue reducing agent, and the glue reducing agent is prepared from the following raw materials, by weight, 30 parts of substituted organic amine, 45 parts of polycarboxylic acid and 60 parts of water; the substituted organic amine is disulfonic acid group-ethanol group diethyl ester amine and triisopropanolamine, and the weight ratio is 1: 3; the polycarboxylic acid is modified polycarboxylic acid, and the preparation method of the modified polycarboxylic acid comprises the following steps: dropwise adding the monomer, the modifier, the initiator and the chain transfer agent into a solvent, reacting at 45 ℃, and adjusting the pH to 6.5 to obtain the modified polycarboxylic acid; the monomer is acrylic acid, methacrylic acid, hydroxyethyl methacrylate and dimethylaminoethyl acrylate, and the weight ratio is 1: 1.5: 0.2: 0.6, the initiator is sodium persulfate which accounts for 2 wt% of the monomers, the chain transfer agent is 3-mercaptopropionic acid which accounts for 0.5 wt% of the monomers, the solvent is water, the modifier is polyoxyethylene sorbitan monooleate, and the weight ratio of the monomers to the modifier is 1: 0.06.

Example 3

The concrete gel reducing agent is provided in the present example, and the specific embodiment is the same as that in example 1, except that the raw materials for preparing the gel reducing agent do not include polycarboxylic acid.

The embodiment also provides a preparation method of the concrete gel reducing agent, and the specific implementation mode is the same as that of the embodiment 1.

Example 4

This example provides a concrete gel reducing agent, which is similar to example 1, except that the polycarboxylic acid does not include a modifier.

Example 5

The concrete gel reducing agent is similar to that in example 4, except that the preparation raw materials of the gel reducing agent comprise 4 parts by weight of substituted organic amine, 30 parts by weight of polycarboxylic acid and 50 parts by weight of water.

Example 6

The concrete gel reducing agent is provided in the embodiment, which is the same as the concrete gel reducing agent in embodiment 4, except that the monomers are acrylic acid, methacrylic acid and dimethylaminoethyl acrylate, and the weight ratio of the acrylic acid to the methacrylic acid to the dimethylaminoethyl acrylate is 1: 1.5: 0.6.

Example 7

The concrete gel reducing agent is provided in the embodiment, which is the same as the concrete gel reducing agent in embodiment 4, except that the monomers are acrylic acid, methacrylic acid and hydroxyethyl methacrylate, and the weight ratio of the monomers is 1: 1.5: 0.2.

Example 8

The concrete gel reducing agent is provided in the embodiment, which is the same as the concrete gel reducing agent in embodiment 4, except that the monomers are acrylic acid, methacrylic acid, hydroxyethyl methacrylate and dimethylaminoethyl acrylate, and the weight ratio of the monomers is 1: 1.5: 0.6: 0.6.

Example 9

The concrete gel reducing agent is provided in the present example, and the specific implementation manner is the same as that in example 1, except that the substituted organic amine is triethanolamine.

Example 10

The concrete gel reducing agent is provided in the present example, and the specific implementation manner is the same as that in example 1, except that the substituted organic amine is triethylesteramine trisulfonate.

Example 11

The concrete gel reducing agent provided by the embodiment is the same as the concrete gel reducing agent provided by the embodiment 1, except that the weight ratio of the monomer to the modifier is 1: 0.2.

Example 12

This example provides a concrete gel reducing agent, which is similar to example 1 except that polyoxyethylene sorbitan monooleate is obtained from tween 80 of guangdong hua chemical limited.

Example 13

This example provides a concrete gel reducing agent, which is similar to example 1 except that the modifier is sorbitan monooleate, which is available from span 80 of Guangdong Hua chemical Co., Ltd.

Evaluation of Performance

The method is characterized in that C30 concrete is taken as an object, the performance of standard concrete without adding an adhesive and concrete prepared by adding the adhesive reducing agent and a commercially available adhesive reducing agent provided by the embodiment is tested, wherein the formula of the concrete is shown in Table 1, the concrete is prepared by taking parts by weight as a unit, the cement is 42.5-grade cement, the fly ash is second-grade fly ash of Hebei Yuran building materials science and technology Limited, the mineral powder is purchased from a Lingsheng Ming mineral product processing factory in Lingshu county, the melon seed slices are purchased from Ningde Tianhua mineral industry Limited, the stone is purchased from Zhanxu mineral product Limited in Lingshu county, the coarse sand is river sand with fineness modulus of 3.7-3.1, the fine sand is sand with fineness modulus of 2.2-1.6, the admixture is sodium lignosulfonate water reducer of Henan Antong environmental protection science and technology Limited, and the commercially available adhesive reducing agent is a L J multifunctional concrete reinforcing agent of Hu.

TABLE 1 concrete formulation

1. Slump: the concrete is prepared by the glue reducing agent provided in the embodiment and the commercially available glue reducing agent according to the concrete formula of the serial number 2, and the initial slump a0 and the slump a1 after 1h are calculated, wherein the slump test method comprises the following steps: pouring concrete into a horn-shaped slump bucket with an upper opening of 100mm, a lower opening of 200mm and a height of 300mm for three times, uniformly impacting 25 times along the wall of the bucket from outside to inside by using a tamping hammer after each filling, tamping and leveling. The barrel is pulled up, the slump of the concrete is generated due to self weight, the height of the highest point of the concrete after the slump is subtracted from the barrel height (300mm), the slump is called as slump, the loss of the slump is calculated to be a0-a1 and is used as a measure of the slump retention, the smaller the loss is, the better the slump retention is, wherein the loss is less than or equal to 5mm in grade 1, more than or equal to 5mm in grade 2, less than or equal to 10mm in grade 3, more than or equal to 20mm in grade 4, more than or equal to 20mm and less than or equal to 30mm in grade 5, and the result is shown in table 2.

2. Concrete wrapping property: the concrete is prepared by the glue reducing agent provided by the embodiment according to the concrete formula of the serial number 2, the wrapping performance is judged according to the degree of the sand surface slurry, the level 1 is that no slurry exists on the exposed sand surface, the level 2 is that the sand surface slurry is not obvious, the level 3 is that the sand surface slurry is general, and the level 4 is that the sand surface slurry is obvious, and the result is shown in the table 2.

Table 2 characterization test of properties

Examples	Slump loss amount	Encapsulation property
			1	Level 1	4 stage
3	Grade 5	Level 1
			4	Stage 2	Grade 3
5	/	Stage 2
			6	Grade 3	/
7	Grade 3	/
			8	4 stage	/

3. Strength: concrete was prepared according to the concrete formulation No. 2 from the gel reducing agent provided in the example and the commercially available gel reducing agent, and the compressive strength was measured according to JC/T2469-2018 for 7 days and 28 days, and compared with the concrete prepared according to No. 1, and the results are shown in table 3.

Table 3 performance characterization test

Examples	7d compressive strength/Mpa	28d compressive strength/MPa
			1	23.1	36.5
4	20.7	36.3
			5	/	32.4
6	20.1	35.6
			7	20.3	35.8
8	19.9	35.2
			9	22.8	35.1
10	22.9	34.8
			11	22.5	33.9
12	21.5	33.4
			13	22.4	35.9
Reference concrete	23.3	36.2
			Commercially available size reduction agents	22.7	35.6

4. And (3) performance testing: concrete was prepared according to the concrete formulation of No. 2 for example 1 and a commercially available paste reducing agent, respectively, and the initial slump, the compressive strength for 7 days and 28 days were measured and compared with the reference concrete provided in No. 1, and the results are shown in table 4.

Table 4 characterization test of properties

	Slump/mm	7d compressive strength/Mpa	28d compressive strength/MPa
				Reference concrete	220	23.3	36.2
Example 1	225	23.1	36.5
				Commercially available size reduction agents	225	22.7	35.6

5. And (3) performance testing: concrete was prepared according to the concrete formulation No. 4 using the gel reducing agent provided in example 2 and a commercially available gel reducing agent, and the compressive strength was measured, and the results are shown in table 5.

Table 5 characterization test of properties

As can be seen from the test results in tables 2 to 5, when the glue reducing agent provided by the invention is used for concrete, the cement consumption can be reduced, and meanwhile, the glue reducing agent has good strength and slump, so that the anisotropy and the processability are improved.

The foregoing examples are merely illustrative and serve to explain some of the features of the method of the present invention. The appended claims are intended to claim as broad a scope as is contemplated, and the examples presented herein are merely illustrative of selected implementations in accordance with all possible combinations of examples. Accordingly, it is applicants' intention that the appended claims are not to be limited by the choice of examples illustrating features of the invention. Also, where numerical ranges are used in the claims, subranges therein are included, and variations in these ranges are also to be construed as possible being covered by the appended claims.

Claims

1. The concrete gel reducing agent is characterized in that the preparation raw materials of the gel reducing agent comprise, by weight, 20-30 parts of substituted organic amine and 40-60 parts of water; the substituent of the substituted organic amine is selected from one or more of ester group, sulfonic group, carboxylic group and hydroxyl.

2. The concrete degelling agent of claim 1, wherein the substituted organic amine with hydroxyl as a substituent is selected from one or more of triethanolamine, triisopropanolamine, N-butyl ethanolamine, methyldiethanolamine, N-diisopropylethanolamine, and tert-butyl ethanolamine.

3. The concrete gel reducing agent of claim 1, wherein the raw materials for preparing the gel reducing agent further comprise polycarboxylic acid, and the monomers of the polycarboxylic acid comprise two or more of acrylic acid, hydroxyethyl acrylate, methacrylic acid, 2-acetamidoacrylic acid, dimethylaminoethyl acrylate, acrylamide, hydroxymethyl acrylamide, diacetone acrylamide and ethyl acetoacetate methacrylate.

4. The concrete degelling agent of claim 3, wherein the monomers of the polycarboxylic acid comprise acrylic acid, methacrylic acid, hydroxyethyl methacrylate, dimethylaminoethyl acrylate, and the weight ratio of 1: (1-2): (0.2-0.3): (0.5 to 1).

5. The concrete gel reducing agent according to claim 3, wherein the polycarboxylic acid is a modified polycarboxylic acid, and the modifier of the modified polycarboxylic acid is one selected from polyoxyethylene sorbitan monooleate, sorbitan monooleate and ethoxylated glycerol monooleate.

6. The concrete degelling agent of claim 5, wherein the weight ratio of the monomer to the modifier is 1: (0.05-0.1).

7. The concrete gel reducing agent according to claim 5, wherein the number average molecular weight of the modifier is 400 to 800.

8. The concrete degelling agent of any one of claims 3 to 7, wherein the weight ratio of the substituted organic amine to the polycarboxylic acid is 1: (1-2).

9. The concrete gel reducing agent of claim 1, wherein the preparation raw materials of the gel reducing agent further comprise auxiliaries, and the auxiliaries comprise one or more of a penetrating agent, a defoaming agent, a dispersing agent, a wetting agent, a thickening agent and a sulfate promoter.

10. The preparation method of the concrete gel reducing agent according to any one of claims 1 to 9, characterized by comprising the following steps: