CN109265064B - Preparation method of high-strength alkali-free chlorine-free accelerator - Google Patents
Preparation method of high-strength alkali-free chlorine-free accelerator Download PDFInfo
- Publication number
- CN109265064B CN109265064B CN201811138388.6A CN201811138388A CN109265064B CN 109265064 B CN109265064 B CN 109265064B CN 201811138388 A CN201811138388 A CN 201811138388A CN 109265064 B CN109265064 B CN 109265064B
- Authority
- CN
- China
- Prior art keywords
- free
- mixed solution
- accelerator
- alkali
- silicon dioxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/10—Accelerators; Activators
- C04B2103/12—Set accelerators
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention discloses a preparation method of a high-strength alkali-free chlorine-free accelerator, which comprises the following steps: the method comprises the following steps: 1) ultrasonically dispersing 2-acrylamide-2-methylpropanesulfonic acid, acrylic acid, a modified nano silicon dioxide solution initiator and water uniformly, heating to 60-80 ℃, and reacting for 5-8h to obtain a mixed solution A; 2) heating aluminum sulfate, alcohol amine, water and the mixed solution A to 60-80 ℃ to react for 1-5h to obtain a mixed solution B; cooling to room temperature, and then dispersing at high speed for 10 minutes by using an emulsifying machine to obtain the high-strength alkali-free chlorine-free accelerator. The alkali-free and chlorine-free setting accelerator prepared by organic modification can greatly improve the 1d compressive strength of cement mortar, and can improve the comprehensive properties of the product such as stability and the like.
Description
Technical Field
The invention belongs to the technical field of concrete admixtures, and particularly relates to a preparation method of a high-strength alkali-free and chlorine-free accelerator.
Background
The accelerator is a concrete admixture which rapidly sets and hardens cement or concrete. The method has the main effects of increasing the primary spraying thickness of the sprayed concrete, shortening the interval between secondary spraying, and simultaneously improving the early strength of the concrete so as to provide support resistance in time, and is widely applied to the engineering of modern underground engineering, mine engineering, leakage stoppage, emergency rescue and the like at present.
The alkali-free accelerator has almost no influence on the later strength of concrete, and is the main development direction of the accelerator, and the alkali-free accelerator taking aluminum sulfate as a main component is a main research object of the accelerator due to the easily available raw material sources and simple preparation process. The aluminum sulfate is not easy to be prepared into the alkali-free accelerator separately, and the problems of stability, early strength and the like need to be solved by combining other components.
Sodium aluminate, magnesium sulfate, calcium chloride, fluoride salt, silicate and the like are common components of an aluminum sulfate alkali-free accelerator, for example, patent CN200610098296.0 discloses a liquid alkali-free accelerator for sprayed concrete, magnesium sulfate is adopted to improve the applicability of the accelerator to cement and improve the early strength of concrete, but the introduction of magnesium sulfate easily causes the crystallization of aluminum sulfate, and causes serious influence on the stability of products. Although hydrofluoric acid is a common component of an aluminum sulfate alkali-free accelerator, the hydrofluoric acid can obviously shorten the setting time and improve the stability of the product, the early strength is very low, and the 1d compressive strength of cement mortar is often less than 3MPa and cannot meet the performance requirements of the standard JC477-2005 accelerator for sprayed concrete.
Disclosure of Invention
The invention provides a preparation method of a high-strength alkali-free chlorine-free accelerator, aiming at solving the defects of low early strength and the like of the existing alkali-free accelerator.
The nano silicon dioxide can effectively promote the hydration of cement and optimize an interface structure, thereby improving the strength of the cement-based composite material. However, the nano silicon dioxide is also a thickening agent, and if the nano silicon dioxide is directly added into the alkali-free accelerator, the viscosity of the product is greatly improved, so that the product is solidified and cannot be practically used. In addition, the surface of the nano silicon dioxide is rich in hydroxyl, so that the nano silicon dioxide is easy to agglomerate, and the grafting rate of direct copolymerization modification is very low.
The preparation method of the strong alkali-free chlorine-free accelerator comprises the following steps:
ultrasonically dispersing and uniformly mixing 2-acrylamide-2-methylpropanesulfonic acid, acrylic acid, modified nano silicon dioxide, an initiator and water, heating to 60-80 ℃, and reacting for 5-8h to obtain a mixed solution A;
heating aluminum sulfate, alcohol amine, water and the mixed solution A to 60-80 ℃ to react for 1-5h to obtain a mixed solution B; cooling to room temperature, and then dispersing at high speed for 10 minutes by using an emulsifying machine to obtain the high-strength alkali-free chlorine-free accelerator.
The invention further improves that the mixed solution A in the step (1) consists of the following components in percentage by mass:
2-acrylamide-2-methylpropanesulfonic acid 10-15%
Acrylic acid 1-5%
20 to 30 percent of modified nano silicon dioxide
0.1 to 1 percent of initiator
Balance of water
The initiator is ammonium persulfate and sodium bisulfite, wherein the molar ratio of the ammonium persulfate to the sodium bisulfite is 2-5: 1.
In the further improvement of the invention, the mixed solution B in the step (2) comprises the following components in percentage by mass:
40 to 60 percent of aluminum sulfate
2 to 12 percent of alcohol amine
The mixed solution A is 6 to 12 percent
Balance of water
The linear speed of the emulsifying machine in the step (2) is 20-30m/s, and the heating temperature is 50-80 ℃.
In a further improvement of the present invention, the alcohol amine is one of diethanolamine or triethanolamine.
In the invention, the preparation method of the modified nano silicon dioxide comprises the following steps:
(1) adding 2g of vacuum-dried nano silicon dioxide into 40ml of N-methyl pyrrolidone, and then dispersing for 1h by using an ultrasonic instrument to obtain uniformly dispersed suspension;
(2) adding 4g of gamma-methacryloxypropyltrimethoxysilane into 40ml of N-methylpyrrolidone, uniformly stirring, and adding into the suspension in the step (1) in three batches;
(3) and transferring the mixed solution into a flask under the protection of nitrogen, stirring and reacting for 24 hours at the temperature of 80 ℃, then carrying out centrifugal separation, washing for 5 times by using ethanol, and finally carrying out vacuum drying at the temperature of 60 ℃ to obtain the modified nano silicon dioxide.
The high-strength alkali-free chlorine-free accelerator is used in the field of sprayed concrete, and the dosage of the accelerator is 6-10wt% of the dosage of cement.
The invention has the beneficial effects that: the alkali-free setting accelerator containing the nano silicon dioxide can fill bonding gaps between hydration products C-S-H gel, improve the interface microstructure of cement and aggregate, and further improve the 1d compressive strength of the product.
Detailed Description
In order to enhance the understanding of the method, the method will be described in further detail with reference to the following examples, which are only used for explaining the method and do not limit the scope of the method.
In order to better understand the invention, the following examples are given for further illustration of the invention, but the invention is not limited to the scope of the examples.
Firstly, preparing modified nano silicon dioxide:
(1) adding 2g of vacuum-dried nano silicon dioxide into 40ml of N-methyl pyrrolidone, and then dispersing for 1h by using an ultrasonic instrument to obtain uniformly dispersed suspension;
(2) adding 4g of gamma-methacryloxypropyltrimethoxysilane into 40ml of N-methylpyrrolidone, uniformly stirring, and adding into the suspension in the step (1) in three batches;
(3) and transferring the mixed solution into a flask under the protection of nitrogen, stirring and reacting for 24 hours at the temperature of 80 ℃, then carrying out centrifugal separation, washing for 5 times by using ethanol, and finally carrying out vacuum drying at the temperature of 60 ℃ to obtain the modified nano silicon dioxide.
Example 1
The preparation method of the high-strength alkali-free chlorine-free accelerator comprises the following steps:
(1) mixing 10g of 2-acrylamide-2-methacrylic acid, 1g of acrylic acid, 20g of nano silicon dioxide, 0.92g of ammonium persulfate, 0.08g of sodium bisulfite and 68.9g of water, heating to 80 ℃, and reacting for 8 hours to obtain a mixed solution A;
(2) heating 60g of aluminum sulfate, 12g of diethanolamine, 12g of the mixed solution A and 16g of water to 80 ℃ for reaction for 5 hours to obtain a mixed solution B; and cooling to room temperature, and then dispersing at high speed for 10 minutes by adopting an emulsifier at the linear velocity of 20m/s to obtain the high-strength alkali-free and chlorine-free accelerator.
Example 2
The preparation method of the high-strength alkali-free chlorine-free accelerator comprises the following steps:
(1) mixing 12g of 2-acrylamide-2-methacrylic acid, 2g of acrylic acid, 20g of nano silicon dioxide, 0.92g of ammonium persulfate, 0.08g of sodium bisulfite and 65g of water, heating to 60 ℃, and reacting for 5 hours to obtain a mixed solution A;
(2) heating 40g of aluminum sulfate, 2g of diethanolamine, 6g of the mixed solution A and 52g of water to 50 ℃ to react for 1h to obtain a mixed solution B; and cooling to room temperature, and then dispersing at high speed for 10 minutes by adopting an emulsifier at the linear velocity of 30m/s to obtain the high-strength alkali-free and chlorine-free accelerator.
Example 3
The preparation method of the high-strength alkali-free chlorine-free accelerator comprises the following steps:
(1) mixing 15g of 2-acrylamide-2-methacrylic acid, 5g of acrylic acid, 30g of nano silicon dioxide, 0.08g of ammonium persulfate, 0.02g of sodium bisulfite and 49.9g of water, heating to 60 ℃, and reacting for 5 hours to obtain a mixed solution A;
(2) heating 50g of aluminum sulfate, 10g of triethanolamine, 8g of mixed solution A and 32g of water to 50 ℃ for reaction for 2 hours to obtain mixed solution B; and cooling to room temperature, and then dispersing at high speed for 10 minutes by adopting an emulsifier at the linear velocity of 25m/s to obtain the high-strength alkali-free and chlorine-free accelerator.
Example 4
The preparation method of the high-strength alkali-free chlorine-free accelerator comprises the following steps:
(1) mixing 14g of 2-acrylamide-2-methacrylic acid, 5g of acrylic acid, 25g of nano silicon dioxide, 0.08g of ammonium persulfate, 0.02g of sodium bisulfite and 55.9g of water, heating to 70 ℃, and reacting for 7 hours to obtain a mixed solution A;
(2) heating 50g of aluminum sulfate, 10g of diethanolamine, 8g of the mixed solution A and 32g of water to 60 ℃ to react for 3 hours to obtain a mixed solution B; and cooling to room temperature, and then dispersing at high speed for 10 minutes by adopting an emulsifier at the linear velocity of 20m/s to obtain the high-strength alkali-free and chlorine-free accelerator.
Comparative example 1
60g of aluminum sulfate, 12g of diethanolamine and 28g of water are heated to 80 ℃ to react for 5h, so as to obtain the alkali-free accelerator.
Comparative example 2
An alkali-free accelerator was prepared by adding 2.4wt% of nano-silica based on comparative example 1.
Comparative example 3
The alkali-free accelerator is prepared by adding 2.4wt% of modified nano-silica based on comparative example 1.
The alkali-free accelerators obtained in examples 1 to 4 and comparative examples 1 to 3 were tested for their performance and the results are shown in Table 1.
The test materials, the setting time and the compression strength refer to the Chinese building material industry standard JC 477-2005. The cement used is P.O 42.5.5 cement produced by Jiangsu Helin cement Co.
The delamination value is: weighing 100ml of alkali-free accelerator into a 100ml measuring cylinder, standing for one week, and visually observing the stability, wherein the volume value of clear liquid appearing in the measuring cylinder is a layering value.
Viscosity number: 100ml of the alkali-free setting accelerator was weighed out and allowed to stand for one week, and the viscosity was measured using a Brookfield Brohler viscometer. And if the product is layered, the viscosity of the product is measured after the product is uniformly stirred.
Table 1 results of performance test of examples and comparative examples
| Examples of Performance | The mixing amount per wt% | Initial setting time/min: s | Final setting time/min: s | 1d compressive strength/MPa | 28d compressive strength/MPa | Delamination value/ml | Viscosity number/cp |
| Example 1 | 8 | 3:10 | 7:00 | 18 | 57 | 0 | 115 |
| Example 2 | 8 | 3:30 | 7:13 | 17 | 53 | 1 | 120 |
| Example 3 | 8 | 3:00 | 7:05 | 18 | 55 | 0 | 116 |
| Example 4 | 8 | 3:05 | 8:00 | 16 | 51 | 0 | 127 |
| Comparative example 1 | 8 | 5:00 | 11:00 | 7.8 | 48 | 65 | 132 |
| Comparative example 2 | 3 | 4:30 | 11:30 | 14 | 56 | 0 | Coagulation |
| Comparative example 3 | 8 | 4:52 | 10:50 | 17 | 51 | 50 | 1603 |
As can be seen from table 1: the alkali-free accelerator only adopting the combination of alcohol amine and aluminum sulfate has poor performance and cannot meet the performance requirement of JC477-2005 standard. After the nano silicon dioxide is introduced, the 1d compressive strength can be obviously improved, but the nano silicon dioxide has a thickening effect, so that the prepared alkali-free setting accelerator has a solidification phenomenon after being placed for one week, cannot be poured out of a measuring cylinder, and cannot meet the field requirement of actual concrete spraying. Although the viscosity of the alkali-free setting accelerator was greatly reduced by the modified nanosilica, the viscosity was still 1603 cp. The alkali-free setting accelerator provided by the invention is modified by the nano-silica polymer, so that the direct compatibility and bonding strength of cement particles and the polymer can be improved, and meanwhile, the alkali-free setting accelerator containing the nano-silica can also fill bonding gaps among hydrated products C-S-H gel, so that the interface microstructure of cement and aggregate is improved, and the 1d compressive strength of the product is improved.
The foregoing shows and describes the basic principles, principal features and advantages of the present method. It will be understood by those skilled in the art that the present method is not limited to the embodiments described above, which are merely illustrative of the principles of the method, but that various changes and modifications may be made to the method without departing from the spirit and scope of the method, which changes and modifications are within the scope of the method as claimed. The scope of the method claimed is defined by the appended claims and equivalents thereof.
Claims (3)
1. A preparation method of a high-strength alkali-free chlorine-free accelerator is characterized by comprising the following steps:
ultrasonically dispersing and uniformly mixing 2-acrylamide-2-methylpropanesulfonic acid, acrylic acid, modified nano silicon dioxide, an initiator and water, heating to 60-80 ℃, and reacting for 5-8h to obtain a mixed solution A;
heating aluminum sulfate, alcohol amine, water and the mixed solution A to 60-80 ℃ to react for 1-5h to obtain a mixed solution B; cooling to room temperature, and then dispersing at high speed for 10 minutes by using an emulsifying machine to obtain the high-strength alkali-free chlorine-free accelerator, wherein the mixed solution A in the step (1) comprises the following components in percentage by mass:
2-acrylamide-2-methylpropanesulfonic acid 10-15%
Acrylic acid 1-5%
20 to 30 percent of modified nano silicon dioxide
0.1 to 1 percent of initiator
Balance of water
The initiator is ammonium persulfate and sodium bisulfite, wherein the molar ratio of the ammonium persulfate to the sodium bisulfite is 2-5: 1;
the mixed solution B in the step (2) comprises the following components in percentage by mass:
40 to 60 percent of aluminum sulfate
2 to 12 percent of alcohol amine
The mixed solution A is 6 to 12 percent
The balance of water;
the preparation method of the modified nano silicon dioxide comprises the following steps:
(1) adding 2g of vacuum-dried nano silicon dioxide into 40ml of N-methyl pyrrolidone, and then dispersing for 1h by using an ultrasonic instrument to obtain uniformly dispersed suspension;
(2) adding 4g of gamma-methacryloxypropyltrimethoxysilane into 40ml of N-methylpyrrolidone, uniformly stirring, and adding into the suspension in the step (1) in three batches;
(3) and transferring the mixed solution into a flask under the protection of nitrogen, stirring and reacting for 24 hours at the temperature of 80 ℃, then carrying out centrifugal separation, washing for 5 times by using ethanol, and finally carrying out vacuum drying at the temperature of 60 ℃ to obtain the modified nano silicon dioxide.
2. The method for preparing a high-strength alkali-free and chlorine-free accelerator according to claim 1, wherein the alcohol amine is one of diethanolamine or triethanolamine.
3. The method for preparing the high-strength alkali-free chlorine-free accelerator as claimed in claim 1 or 2, wherein the high-strength alkali-free chlorine-free accelerator is used in the field of shotcrete, and the addition amount thereof is 6-10wt% of the amount of cement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811138388.6A CN109265064B (en) | 2018-09-28 | 2018-09-28 | Preparation method of high-strength alkali-free chlorine-free accelerator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811138388.6A CN109265064B (en) | 2018-09-28 | 2018-09-28 | Preparation method of high-strength alkali-free chlorine-free accelerator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109265064A CN109265064A (en) | 2019-01-25 |
| CN109265064B true CN109265064B (en) | 2021-04-20 |
Family
ID=65198742
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811138388.6A Active CN109265064B (en) | 2018-09-28 | 2018-09-28 | Preparation method of high-strength alkali-free chlorine-free accelerator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109265064B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110606695A (en) * | 2019-10-17 | 2019-12-24 | 江苏兆佳建材科技有限公司 | Modified polycarboxylate superplasticizer and preparation method thereof |
| CN110981266B (en) * | 2019-11-27 | 2022-03-18 | 江苏苏博特新材料股份有限公司 | Special anti-settling agent for alkali-free accelerator, and preparation method and application thereof |
| CN111646728B (en) * | 2020-07-01 | 2021-11-09 | 中建材中岩科技有限公司 | Quick-setting high-strength alkali-free liquid accelerator |
| CN112723787A (en) * | 2020-12-30 | 2021-04-30 | 山西佳维新材料股份有限公司 | Fluorine-free liquid accelerator and preparation method and application thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102037023A (en) * | 2008-05-21 | 2011-04-27 | 巴斯夫欧洲公司 | Graft copolymer, method for the production thereof, and use thereof |
| CN103664034A (en) * | 2013-11-15 | 2014-03-26 | 交通运输部公路科学研究所 | Liquid accelerator for sprayed concrete and preparation method and application thereof |
| JP2014152055A (en) * | 2013-02-06 | 2014-08-25 | Denki Kagaku Kogyo Kk | Liquid quick setting agent, cement composition using the same, and spraying method |
| CN104386976A (en) * | 2014-10-13 | 2015-03-04 | 中铁二院重庆勘察设计研究院有限责任公司 | Modified accelerator and composite quick-setting cement slurry with easy-to-control viscosity, and preparation method thereof |
| CN104762077A (en) * | 2014-12-09 | 2015-07-08 | 西南石油大学 | High-temperature-resistant salt-resistant polymer oil-displacement agent |
| CN106632917A (en) * | 2016-12-23 | 2017-05-10 | 卫辉市化工有限公司 | Preparation method of polymer fluid loss agent for sulphoaluminate cement |
| CN108101403A (en) * | 2017-12-28 | 2018-06-01 | 科之杰新材料集团有限公司 | A kind of preparation method of environment-friendly type alkali-free liquid accelerator |
-
2018
- 2018-09-28 CN CN201811138388.6A patent/CN109265064B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102037023A (en) * | 2008-05-21 | 2011-04-27 | 巴斯夫欧洲公司 | Graft copolymer, method for the production thereof, and use thereof |
| JP2014152055A (en) * | 2013-02-06 | 2014-08-25 | Denki Kagaku Kogyo Kk | Liquid quick setting agent, cement composition using the same, and spraying method |
| CN103664034A (en) * | 2013-11-15 | 2014-03-26 | 交通运输部公路科学研究所 | Liquid accelerator for sprayed concrete and preparation method and application thereof |
| CN104386976A (en) * | 2014-10-13 | 2015-03-04 | 中铁二院重庆勘察设计研究院有限责任公司 | Modified accelerator and composite quick-setting cement slurry with easy-to-control viscosity, and preparation method thereof |
| CN104762077A (en) * | 2014-12-09 | 2015-07-08 | 西南石油大学 | High-temperature-resistant salt-resistant polymer oil-displacement agent |
| CN106632917A (en) * | 2016-12-23 | 2017-05-10 | 卫辉市化工有限公司 | Preparation method of polymer fluid loss agent for sulphoaluminate cement |
| CN108101403A (en) * | 2017-12-28 | 2018-06-01 | 科之杰新材料集团有限公司 | A kind of preparation method of environment-friendly type alkali-free liquid accelerator |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109265064A (en) | 2019-01-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109265064B (en) | Preparation method of high-strength alkali-free chlorine-free accelerator | |
| CN105293974B (en) | A kind of concrete is combined super instant coagulant and its application method | |
| CN111807804B (en) | Sand-free paste-based self-leveling mortar and preparation method thereof | |
| CN108623741A (en) | A kind of organic low alkali accelerator of formation inierpeneirating network structure and preparation method thereof | |
| CN110627397B (en) | High-strength alkali-free liquid accelerator, preparation method and application thereof | |
| CN111018392B (en) | Method for synthesizing fluoride-free alkali-free accelerator at normal temperature | |
| CN109369859B (en) | Concrete tackifying type viscosity regulator and preparation method thereof | |
| CN110395939B (en) | Waterproof enhanced alkali-free liquid accelerator and preparation method thereof | |
| CN104876468A (en) | Functionalized polycarboxylic acid water reducer matched with silica fume and preparation method thereof | |
| CN109180133B (en) | Polymer anti-crack dry powder plastering mortar and polymer anti-crack plastering mortar | |
| CN111377649A (en) | Low-sulfur polyaluminum type alkali-free accelerator and preparation method thereof | |
| CN108821640B (en) | Concrete mortar anti-cracking additive and preparation method thereof | |
| CN108328977A (en) | A kind of concrete repairing material | |
| CN115215574B (en) | Aluminum-based concrete microcrack self-repairing material, composition, preparation method and application thereof | |
| CN110156398B (en) | High-strength concrete and preparation method thereof | |
| CN113372083B (en) | Graphene oxide based layered material modified self-leveling mortar and preparation method thereof | |
| CN111377655B (en) | Covalent bond type alkali-free accelerator and preparation method thereof | |
| CN111377654B (en) | Hybrid alkali-free accelerator and preparation method thereof | |
| CN111003964B (en) | Alkali-free liquid accelerator and production process thereof | |
| WO2024082735A1 (en) | Organic-inorganic composite toughening material and use thereof in concrete | |
| CN111943560A (en) | Low-resilience alkali-free liquid accelerator and preparation method thereof | |
| CN111606625A (en) | Formula and preparation method of C70 high-strength self-compacting concrete | |
| CN114853433B (en) | Fluorine gypsum composite cementing material and preparation method thereof | |
| CN110330280A (en) | A kind of wet-mixing plastering mortar and preparation method thereof | |
| CN112811849B (en) | Retarder for cement-based materials |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |