CN106589255A - High-water-reduction slump-retaining polycarboxylate superplasticizer and preparation method thereof - Google Patents

High-water-reduction slump-retaining polycarboxylate superplasticizer and preparation method thereof Download PDF

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Publication number
CN106589255A
CN106589255A CN201611227403.5A CN201611227403A CN106589255A CN 106589255 A CN106589255 A CN 106589255A CN 201611227403 A CN201611227403 A CN 201611227403A CN 106589255 A CN106589255 A CN 106589255A
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CN
China
Prior art keywords
reducing agent
carboxylic acid
acid water
water reducing
high
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CN201611227403.5A
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Chinese (zh)
Inventor
徐伦
徐一伦
李同新
王寅
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陕西友邦新材料科技有限公司
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Priority to CN201611227403.5A priority Critical patent/CN106589255A/en
Publication of CN106589255A publication Critical patent/CN106589255A/en

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Classifications

    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B24/00Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
    • C04B24/24Macromolecular compounds
    • C04B24/26Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B24/2605Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing polyether side chains
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F283/00Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
    • C08F283/06Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polyethers, polyoxymethylenes or polyacetals
    • C08F283/065Macromolecular 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
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2103/00Function or property of ingredients for mortars, concrete or artificial stone
    • C04B2103/30Water reducers, plasticisers, air-entrainers, flow improvers
    • C04B2103/302Water reducers

Abstract

The invention provides a high-water-reduction slump-retaining polycarboxylate superplasticizer and a preparation method thereof. The high-water-reduction slump-retaining polycarboxylate superplasticizer is obtained by performing copolymerization reaction among a big polyether monomer, an unsaturated monomer and a hydroxyl ester monomer under the action of an initiator and a molecular weight regulator, and then adding an alkaline solution to neutralize the pH value to be 7-8. The polycarboxylate superplasticizer provided by the invention can keep the slump degree of concrete from fast loss while having high water reduction performance of a traditional polycarboxylate superplasticizer, and greatly expands the application range of the polycarboxylate superplasticizer, so that the high-water-reduction slump-retaining polycarboxylate superplasticizer not only is suitable for various types of cement, but also is simple in preparation process and is environment-friendly and pollution-free.

Description

High diminishing collapse protective poly-carboxylic acid water reducing agent and preparation method thereof

Technical field

The present invention relates to technical field of concrete additives, more particularly to high diminishing collapse protective poly-carboxylic acid water reducing agent and its system Preparation Method.

Background technology

Cement water reducing agent is maximum is measured used in concrete admixture most widely used, and can significantly improve mixed Solidifying soil nature energy, is considered the BSA of concrete.At present, high-performance water reducing agent has with poly carboxylic acid series water reducer as representative Yield poorly, water-reducing rate is high, the advantages of slump-retaining preferable, water-reducing rate is 26~43% or so, and synthesis technique is simple, Production process pollution is few, and environmental protection, cost performance is high, is acknowledged as concrete admixture developing direction from now on.

At this stage, the raw material due to various places and the influence factor such as fluctuation of weather, conventional polycarboxylate water-reducer conduct After concrete admixture use, the performance of the water-reducing effect at initial stage is good, but the too fast phenomenon of slump-loss occurs, for applying Work progress and trucd mixer transportation are very unfavorable, it is impossible to meet while high diminishing, it is ensured that its function of slump protection.

The content of the invention

For the drawbacks described above and problem of prior art, it is an object of the invention to provide a kind of high diminishing collapse protective poly-carboxylic acid Water reducer and preparation method thereof.The present invention from polyether macromonomer, unsaturated monomer and hydroxy ester compound copolymerization by obtaining height Diminishing collapse protective poly-carboxylic acid water reducing agent, the absorption and dispersion principle according to water reducer, by control water reducer on cement granules Initial adsorption amount and the rate of adsorption can efficiently control the slump-loss degree of fresh concrete.Solve existing poly- Carboxylic acid water reducer can not simultaneously meet the technical problem of high diminishing and collapse protection type.

In order to achieve the above object, the present invention provides following technical scheme:

The high diminishing collapse protective poly-carboxylic acid water reducing agent of the present invention, is by polyether macromonomer, unsaturated monomer and hydroxy ester After monomer is copolymerized in the presence of initiator and molecular weight regulator, adds in alkaline solution and pH value is to 7~8 After obtain;Wherein, the mass ratio of the polyether macromonomer, unsaturated monomer and ester monomers is 335~362:28~37:25 ~33.

Further, the mass ratio of the polyether macromonomer, unsaturated monomer and ester monomers is 350~362:30~ 35:30~33.

Further, the unsaturated monomer is maleic anhydride.

Further, the initiator includes oxidants hydrogen peroxide and reducing agent ascorbic acid;And the initiator Consumption is the 3.2%~3.9% of polyether macromonomer, unsaturated monomer and ester monomers gross mass.

Specifically, the concentration of oxidants hydrogen peroxide is 30%.

Further, the molecular weight regulator is mercaptopropionic acid;And the consumption of the molecular weight regulator is that polyethers is big The 3.2%~3.9% of monomer, unsaturated monomer and ester monomers gross mass.

Further, the consumption of the alkaline solution is total matter of polyether macromonomer, unsaturated monomer and ester monomers The 1.4%~2.3% of amount.

Preferably, the alkaline solution is sodium hydroxide.

Further, the weight average molecular weight of the polyether macromonomer is 1000~5000.

Preferably, polyether macromonomer used in the present invention is the poly- carboxylics of zx-504 of Jilin Zhong Xin Chemical Co., Ltd.s production Sour water reducer monomer, weight average molecular weight is 2400.

The preparation method of the high diminishing collapse protective poly-carboxylic acid water reducing agent of the present invention, comprises the steps:

Step one, polyether macromonomer and unsaturated monomer are measured by proportioning mix in deionized water, be warming up to 40 DEG C, plus To enter stir after oxidant 15~25min and obtain clear solution;

Step 2, the reducing agent of proportional quantity and molecular weight regulator are mixed, mixed liquor and ester monomers are dripped respectively Add to and be incubated after being copolymerized in clear solution obtained in step one;

Step 3, reuse alkaline solution that mass concentration is 32% and adjust solution ph to 7.0~8.0, after cooling i.e. Obtain high diminishing collapse protective poly-carboxylic acid water reducing agent.

Further, in step 2, the time for adding of ester monomers is controlled in 2.3~2.8h, reducing agent and molecular weight The time for adding of regulator mixed liquor is controlled in 2.7~3.2h.

Further, in step 2, deionized water is required supplementation with during Deca, the solid content for maintaining solution system exists 37%~44%.

Absorption and dispersion principle of the present invention according to water reducer, due to absorption speed of the polycarboxylate water-reducer on cement granules Rate depends not only on its molecular structure, molecular weight and molecular conformation, additionally depends on the type and density of molecular backbone functional group, such as Hydroxy acid base (- COO-) etc. these active hydrophilic groups and cement there is good binding ability, be the anchoring group of absorption, these Group is more in molecular backbone, and water reducer is faster in the rate of adsorption of cement granules.Therefore, it can setting by molecular structure Meter, controls the rate of adsorption of the poly carboxylic acid series water reducer on cement granules and hydrated product, so as to realize poly carboxylic acid series water reducer Gradually play its peptizaiton, rather than whole quick releases its all of dispersibilities.

In polycarboxylate water-reducer molecule or intermolecular combination ester group, anhydrides non-hydrophilic group, with cement water Change carrying out, hydrated cementitious provide high alkalinity environment under ester group either anhydride group produce hydrolysis and change into hydroxyl or Other easily produce the group of absorption on cement granules, play its peptizaiton, make polycarboxylate water-reducer take into account high diminishing While also have collapse protection type concurrently.

In addition, the high diminishing collapse protective poly-carboxylic acid water reducing agent of the present invention can adapt to various cement, with traditional poly- carboxylic While sour water reducer high water-reducing property, the slump of concrete not immediate loss can be kept again, have greatly expanded polycarboxylic acids The use range of water reducer, preparation process is simple, green non-pollution.

Specific embodiment

Below in conjunction with embodiments of the invention, technical scheme is clearly and completely described, it is clear that Described embodiment is only a part of embodiment of the invention, rather than the embodiment of whole.Based on the enforcement in the present invention Example, the every other embodiment that those of ordinary skill in the art are obtained under the premise of creative work is not made is belonged to The scope of protection of the invention.

The polyether macromonomer that the embodiment of the present invention is used is the zx-504 polycarboxylic acids of Jilin Zhong Xin Chemical Co., Ltd.s production Water reducer monomer, its weight average molecular weight is 2400.

Embodiment 1

The high diminishing collapse protective poly-carboxylic acid water reducing agent of the present embodiment 1, polyether macromonomer, maleic anhydride and ester monomers Mass ratio is 335:28:25, on the basis of the gross mass of polyether macromonomer, maleic anhydride and ester monomers, oxidant and also The consumption of former agent is the 3.2% of gross mass, and the consumption of molecular regulation agent mercaptopropionic acid is the 0.75% of gross mass, sodium hydroxide Consumption is the 1.4% of gross mass.

It is according to proportional quantity, many prosperous zx-504 polycarboxylate water-reducers monomers and maleic anhydride are water-soluble with a certain amount of deionization Solution is warming up to 40 DEG C in reactor, disposable to add the hydrogenperoxide steam generator that concentration is 30%, stirs 20min, makes polycarboxylic acids Water reducer monomer and maleic anhydride all dissolve, transparent to solution, without precipitation.Add hydrogenperoxide steam generator, Deca hydroxyl It is added dropwise to complete in ester solution, and 2.3h, and while the mixed solution of Deca ascorbic acid and mercaptopropionic acid, drips in 2.7h Into, 1~2h is incubated after completion of dropping, plus deionized water regulation system solid content is 37%~44%, finally using alkali neutralisation Sodium hydroxide solution is added, the solution that pH is 7~8 is obtained and is high diminishing collapse protective poly-carboxylic acid water reducing agent HPEC-1.

Embodiment 2

The high diminishing collapse protective poly-carboxylic acid water reducing agent of the present embodiment 2, polyether macromonomer, maleic anhydride and ester monomers Mass ratio is 350:30:31, on the basis of the gross mass of polyether macromonomer, maleic anhydride and ester monomers, oxidant and also The consumption of former agent is the 3.5% of gross mass, and the consumption of molecular regulation agent mercaptopropionic acid is the 0.85% of gross mass, sodium hydroxide Consumption is the 1.7% of gross mass.

It is according to proportional quantity, many prosperous zx-504 polycarboxylate water-reducers monomers and maleic anhydride are water-soluble with a certain amount of deionization Solution is warming up to 40 DEG C in reactor, disposable to add the hydrogenperoxide steam generator that concentration is 30%, stirs 20min, makes polycarboxylic acids Water reducer monomer and maleic anhydride all dissolve, transparent to solution, without precipitation.Add hydrogenperoxide steam generator, Deca hydroxyl It is added dropwise to complete in ester solution, and 2.5h, and while the mixed solution of Deca ascorbic acid and mercaptopropionic acid, drips in 2.9h Into, 1~2h is incubated after completion of dropping, plus deionized water regulation system solid content is 37%~44%, finally using alkali neutralisation Sodium hydroxide solution is added, the solution that pH is 7~8 is obtained and is high diminishing collapse protective poly-carboxylic acid water reducing agent HPEC-2.

Embodiment 3

The high diminishing collapse protective poly-carboxylic acid water reducing agent of the present embodiment 3, polyether macromonomer, maleic anhydride and ester monomers Mass ratio is 362:37:33, on the basis of the gross mass of polyether macromonomer, maleic anhydride and ester monomers, oxidant and also The consumption of former agent is the 3.9% of gross mass, and the consumption of molecular regulation agent mercaptopropionic acid is the 0.92% of gross mass, sodium hydroxide Consumption is the 2.3% of gross mass.

It is according to proportional quantity, many prosperous zx-504 polycarboxylate water-reducers monomers and maleic anhydride are water-soluble with a certain amount of deionization Solution is warming up to 40 DEG C in reactor, disposable to add the hydrogenperoxide steam generator that concentration is 30%, stirs 20min, makes polycarboxylic acids Water reducer monomer and maleic anhydride all dissolve, transparent to solution, without precipitation.Add hydrogenperoxide steam generator, Deca hydroxyl It is added dropwise to complete in ester solution, and 2.5h, and while the mixed solution of Deca ascorbic acid and mercaptopropionic acid, drips in 2.9h Into, 1~2h is incubated after completion of dropping, plus deionized water regulation system solid content is 37%~44%, finally using alkali neutralisation Sodium hydroxide solution is added, the solution that pH is 7~8 is obtained and is high diminishing collapse protective poly-carboxylic acid water reducing agent HPEC-3.

Each embodiment Product checking analysis

Each embodiment effect test is detected according to GB/T8077-2012《Concrete admixture homogeneity test method》Carry out Net slurry detection.According to GB/T50080-2002《Standard for test methods of properties of ordinary concrete mixture》Test concrete fluidity, collapse Slump-loss when degree of falling and Jing.The volume of water reducer is the solid volume of folding.

1st, paste flowing degree experiment

Cement, Carnis Rapanae thomasianae cement P42.5, Ji east cement P42.5 and China Resources cement P on the basis of net slurry testing cement 42.5 4 kinds of cement, obtained experimental result is shown in Table 1.

The paste flowing degree Experimental comparison's table of table 1

2nd, concrete test

Concrete mix is:Cement 290kg/m3, flyash 90kg/m3, sand in IIth area that modulus of fineness is 2.4 734kg/m3, rubble, particle diameter be 5~20mm 1098kg/m3.Experimental result is as shown in table 2.

The concrete test contrast table of table 2

The above, the only specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, any Those familiar with the art the invention discloses technical scope in, change or replacement can be readily occurred in, all should contain Cover within protection scope of the present invention.Therefore, protection scope of the present invention described should be defined by scope of the claims.

Claims (10)

1. high diminishing collapse protective poly-carboxylic acid water reducing agent, it is characterised in that:It is by polyether macromonomer, unsaturated monomer and hydroxy ester After monomer is copolymerized in the presence of initiator and molecular weight regulator, adds in alkaline solution and pH value is to 7~8 After obtain;Wherein, the mass ratio of the polyether macromonomer, unsaturated monomer and ester monomers is 335~362:28~37:25 ~33.
2. high diminishing collapse protective poly-carboxylic acid water reducing agent according to claim 1, it is characterised in that:The polyether macromonomer, The mass ratio of unsaturated monomer and ester monomers is 350~362:30~35:30~33.
3. the high diminishing collapse protective poly-carboxylic acid water reducing agent according to claims 1 or 2, it is characterised in that:The unsaturation Monomer is maleic anhydride.
4. the high diminishing collapse protective poly-carboxylic acid water reducing agent according to claims 1 or 2, it is characterised in that:The initiator Including oxidants hydrogen peroxide and reducing agent ascorbic acid;And the consumption of the initiator is polyether macromonomer, unsaturated monomer With the 3.2%~3.9% of ester monomers gross mass.
5. the high diminishing collapse protective poly-carboxylic acid water reducing agent according to claims 1 or 2, it is characterised in that:The molecular weight Regulator is mercaptopropionic acid;And the consumption of the molecular weight regulator is polyether macromonomer, unsaturated monomer and ester monomers The 3.2%~3.9% of gross mass.
6. the high diminishing collapse protective poly-carboxylic acid water reducing agent according to claims 1 or 2, it is characterised in that:The alkalescence is molten The consumption of liquid is the 1.4%~2.3% of the gross mass of polyether macromonomer, unsaturated monomer and ester monomers.
7. the high diminishing collapse protective poly-carboxylic acid water reducing agent according to claims 1 or 2, it is characterised in that:The polyethers is big The weight average molecular weight of monomer is 1000~5000.
8. the preparation method of the high diminishing collapse protective poly-carboxylic acid water reducing agent according to claim 1 to 7 any one, its feature It is to comprise the steps:
Step one, polyether macromonomer and unsaturated monomer are measured by proportioning mix in deionized water, be warming up to 40 DEG C, add oxygen 15~25min is stirred after agent and obtains clear solution;
Step 2, the reducing agent of proportional quantity and molecular weight regulator are mixed, mixed liquor and ester monomers are dropped to respectively It is incubated after being copolymerized in clear solution obtained in step one;
Step 3, reuse alkaline solution that mass concentration is 32% and adjust solution ph to 7.0~8.0, height is obtained final product after cooling Diminishing collapse protective poly-carboxylic acid water reducing agent.
9. the preparation method of high diminishing collapse protective poly-carboxylic acid water reducing agent according to claim 8, it is characterised in that step 2 In, the time for adding of ester monomers is controlled in 2.3~2.8h, the time for adding control of reducing agent and molecular weight regulator mixed liquor System is in 2.7~3.2h.
10. the preparation method of high diminishing collapse protective poly-carboxylic acid water reducing agent according to claim 8, it is characterised in that step In two, deionized water is required supplementation with during Deca, maintain the solid content of solution system 37%~44%.
CN201611227403.5A 2016-12-27 2016-12-27 High-water-reduction slump-retaining polycarboxylate superplasticizer and preparation method thereof CN106589255A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101928114A (en) * 2010-08-30 2010-12-29 大连建科北方化学有限公司 High water reduction high collapse protection type polycarboxylate high-performance water reducer and pyrogen-free preparation method thereof
CN103275280A (en) * 2013-06-17 2013-09-04 武汉东彭科技发展有限公司 Synthetic method for polycarboxylate type high slump-retaining water reducing agent at normal temperature
CN104371073A (en) * 2014-10-30 2015-02-25 中铁四局集团有限公司 Normal-temperature preparation method of slow-release polycarboxylic acid water reducing agent
CN105110687A (en) * 2015-07-30 2015-12-02 厦门路桥翔通建材科技有限公司 Mud resisting and slump retaining type polycarboxylic acids water reducer and preparation method thereof
CN105601837A (en) * 2015-11-26 2016-05-25 重庆建研科之杰新材料有限公司 Polycarboxylate superplasticizer and preparation method thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101928114A (en) * 2010-08-30 2010-12-29 大连建科北方化学有限公司 High water reduction high collapse protection type polycarboxylate high-performance water reducer and pyrogen-free preparation method thereof
CN103275280A (en) * 2013-06-17 2013-09-04 武汉东彭科技发展有限公司 Synthetic method for polycarboxylate type high slump-retaining water reducing agent at normal temperature
CN104371073A (en) * 2014-10-30 2015-02-25 中铁四局集团有限公司 Normal-temperature preparation method of slow-release polycarboxylic acid water reducing agent
CN105110687A (en) * 2015-07-30 2015-12-02 厦门路桥翔通建材科技有限公司 Mud resisting and slump retaining type polycarboxylic acids water reducer and preparation method thereof
CN105601837A (en) * 2015-11-26 2016-05-25 重庆建研科之杰新材料有限公司 Polycarboxylate superplasticizer and preparation method thereof

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