CN114276499B - 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 PDFInfo
- Publication number
- CN114276499B CN114276499B CN202110415153.2A CN202110415153A CN114276499B CN 114276499 B CN114276499 B CN 114276499B CN 202110415153 A CN202110415153 A CN 202110415153A CN 114276499 B CN114276499 B CN 114276499B
- Authority
- CN
- China
- Prior art keywords
- water
- parts
- slump
- acrylic acid
- tpeg
- 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
- 229920005646 polycarboxylate Polymers 0.000 title claims abstract description 54
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 239000008030 superplasticizer Substances 0.000 title claims description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 116
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 83
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 claims abstract description 46
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims abstract description 46
- 239000006087 Silane Coupling Agent Substances 0.000 claims abstract description 37
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 claims abstract description 36
- DKIDEFUBRARXTE-UHFFFAOYSA-N 3-mercaptopropanoic acid Chemical compound OC(=O)CCS DKIDEFUBRARXTE-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910001870 ammonium persulfate Inorganic materials 0.000 claims abstract description 18
- 239000008367 deionised water Substances 0.000 claims abstract description 17
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 17
- AEQDJSLRWYMAQI-UHFFFAOYSA-N 2,3,9,10-tetramethoxy-6,8,13,13a-tetrahydro-5H-isoquinolino[2,1-b]isoquinoline Chemical compound C1CN2CC(C(=C(OC)C=C3)OC)=C3CC2C2=C1C=C(OC)C(OC)=C2 AEQDJSLRWYMAQI-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000003513 alkali Substances 0.000 claims abstract description 10
- 239000007788 liquid Substances 0.000 claims abstract description 10
- 229940005574 sodium gluconate Drugs 0.000 claims abstract description 10
- 235000012207 sodium gluconate Nutrition 0.000 claims abstract description 10
- 239000000176 sodium gluconate Substances 0.000 claims abstract description 10
- HRZFUMHJMZEROT-UHFFFAOYSA-L sodium disulfite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])(=O)=O HRZFUMHJMZEROT-UHFFFAOYSA-L 0.000 claims abstract description 3
- 229940001584 sodium metabisulfite Drugs 0.000 claims abstract description 3
- 235000010262 sodium metabisulphite Nutrition 0.000 claims abstract description 3
- 238000006243 chemical reaction Methods 0.000 claims description 32
- 239000000463 material Substances 0.000 claims description 26
- 238000000034 method Methods 0.000 claims description 11
- 238000003756 stirring Methods 0.000 claims description 11
- 238000002156 mixing Methods 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 6
- DKGAVHZHDRPRBM-UHFFFAOYSA-N Tert-Butanol Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 4
- 230000008569 process Effects 0.000 claims description 3
- CSMWJXBSXGUPGY-UHFFFAOYSA-L sodium dithionate Chemical compound [Na+].[Na+].[O-]S(=O)(=O)S([O-])(=O)=O CSMWJXBSXGUPGY-UHFFFAOYSA-L 0.000 claims 1
- 239000002253 acid Substances 0.000 abstract description 22
- 230000014759 maintenance of location Effects 0.000 abstract description 14
- 230000009467 reduction Effects 0.000 abstract description 8
- 238000004519 manufacturing process Methods 0.000 abstract description 4
- 239000004568 cement Substances 0.000 description 45
- 239000012986 chain transfer agent Substances 0.000 description 16
- 239000006185 dispersion Substances 0.000 description 13
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 11
- 239000004567 concrete Substances 0.000 description 9
- 230000007423 decrease Effects 0.000 description 8
- 230000000694 effects Effects 0.000 description 8
- 238000002474 experimental method Methods 0.000 description 8
- 239000003999 initiator Substances 0.000 description 8
- 239000000178 monomer Substances 0.000 description 8
- 239000007800 oxidant agent Substances 0.000 description 8
- 230000001590 oxidative effect Effects 0.000 description 8
- 238000006722 reduction reaction Methods 0.000 description 7
- 230000015572 biosynthetic process Effects 0.000 description 5
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 5
- 238000003786 synthesis reaction Methods 0.000 description 5
- 239000004576 sand Substances 0.000 description 4
- 239000007787 solid Substances 0.000 description 3
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229920000056 polyoxyethylene ether Polymers 0.000 description 2
- 229940051841 polyoxyethylene ether Drugs 0.000 description 2
- 238000010526 radical polymerization reaction Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 230000002194 synthesizing effect Effects 0.000 description 2
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229920005551 calcium lignosulfonate Polymers 0.000 description 1
- RYAGRZNBULDMBW-UHFFFAOYSA-L calcium;3-(2-hydroxy-3-methoxyphenyl)-2-[2-methoxy-4-(3-sulfonatopropyl)phenoxy]propane-1-sulfonate Chemical compound [Ca+2].COC1=CC=CC(CC(CS([O-])(=O)=O)OC=2C(=CC(CCCS([O-])(=O)=O)=CC=2)OC)=C1O RYAGRZNBULDMBW-UHFFFAOYSA-L 0.000 description 1
- 239000011083 cement mortar Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000002687 intercalation Effects 0.000 description 1
- 238000009830 intercalation Methods 0.000 description 1
- QVDTXNVYSHVCGW-ONEGZZNKSA-N isopentenol Chemical compound CC(C)\C=C\O QVDTXNVYSHVCGW-ONEGZZNKSA-N 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 230000033116 oxidation-reduction process Effects 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 150000003254 radicals Chemical class 0.000 description 1
- 238000006479 redox reaction Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 150000003384 small molecules Chemical class 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Landscapes
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention provides a high water-reducing slump-retaining polycarboxylate water reducer and a preparation method thereof, wherein the high water-reducing slump-retaining polycarboxylate water reducer comprises the following components in parts by weight: 320-340 parts of TPEG, 450-490 parts of deionized water, 3.2-3.4 parts of ammonium persulfate, 33-35 parts of acrylic acid, 0.8-1 part of mercaptopropionic acid, 4.4-4.6 parts of silane coupling agent, 0.9-1.1 parts of sodium metabisulfite, 19-21 parts of sodium gluconate, 19-21 parts of liquid alkali and 110-120 parts of water. The polycarboxylic acid water reducer with high water reduction and slump retention provided by the invention is synthesized at normal temperature, has the advantages of simple production process, excellent performance and high cost performance, and can simultaneously meet the requirements of high water reduction and slump retention.
Description
Technical Field
The invention relates to a high water-reducing slump-retaining polycarboxylate superplasticizer and a preparation method thereof.
Background
The development of the water reducer is divided into three stages: a first-generation common water reducing agent stage represented by calcium lignosulfonate; a second generation high efficiency water reducing agent stage represented by naphthalene; and a third-generation high-performance water reducing agent stage represented by polycarboxylic acid series.
In the synthetic process, the polycarboxylic acid type high-performance water reducer adopts unsaturated monomer free radical polymerization, and the synthetic raw materials are very many, and generally acrylic acid, polyoxyethylene ether and the like. In the molecular structure, the molecular structure of the polycarboxylic acid high-performance water reducer is a linear comb structure, and a main chain is polymerized with a plurality of different active groups, such as carboxyl (-cooh), hydroxyl (-oh), sulfonic group (-so 3 na) and the like, so that electrostatic repulsion effect can be generated, and the side chain of the polycarboxylic acid high-performance water reducer is provided with a hydrophilic nonpolar active group and has a higher steric hindrance effect. Because of the wide raw material sources and unique molecular structure, the composite material belongs to a green environment-friendly product, and becomes one of the key points and hot spots in the field of concrete admixture research.
The polycarboxylic acid ether on the market is mainly divided into two types of water-reducing type and slump-retaining type, the water-reducing rate of the water-reducing type polycarboxylic acid ether can reach more than 30%, but the water-reducing type polycarboxylic acid ether has no slump-retaining capacity, but the slump-retaining capacity of the slump-retaining type polycarboxylic acid ether is strong, but the water-reducing rate is only about 10%, so that two or more polycarboxylic acid ethers are required to be compounded into a finished product, certain inconvenience factors exist in production, a storage tank is required to be additionally arranged, and the production is complicated.
Disclosure of Invention
The invention aims to solve the technical problems, firstly provides a water reducer with high water reducing rate and slump retaining capacity, and secondly provides a simpler preparation method of the water reducer.
In a first aspect, a high water-reducing slump-retaining polycarboxylate superplasticizer is provided, which comprises the following components in parts by weight:
320-340 parts of TPEG, 450-490 parts of deionized water, 3.2-3.4 parts of ammonium persulfate, 33-35 parts of acrylic acid, 0.8-1 part of mercaptopropionic acid, 4.4-4.6 parts of silane coupling agent, 0.9-1.1 parts of sodium metabisulfite, 19-21 parts of sodium gluconate, 19-21 parts of liquid alkali and 110-120 parts of water.
Preferably, the molar ratio of acrylic acid to TPEG is 2.7:1.
preferably, the molar ratio of the silane coupling agent to TPEG is 0.3:1.
preferably, the mass ratio of mercaptopropionic acid to TPEG is 0.003:1.
preferably, the mass ratio of ammonium persulfate to the white hanging block is 1.65:1.
Preferably, TPEG330, deionized water 470, ammonium persulfate 3.3, acrylic acid 34, mercaptopropionic acid 0.9, silane coupling agent 4.5, sodium gluconate 20, liquid alkali 20, water 116.
In a second aspect, a preparation method of the high water-reducing slump-retaining polycarboxylate superplasticizer is provided, and the high water-reducing slump-retaining polycarboxylate superplasticizer comprises the following components in parts by weight:
s10: adding all TPEG (t-butyl alcohol), 40% -45% of deionized water, 48% -52% of ammonium persulfate and 18% -23% of acrylic acid into a reaction kettle, and sealing the reaction kettle;
preparing the material A and uniformly mixing: 23% -28% of deionized water, 57% -62% of acrylic acid, all mercaptopropionic acid and all silane coupling agents;
preparing material B and uniformly mixing: the rest deionized water and all hanging white blocks;
s20: opening the reaction kettle under the normal temperature condition, adding the rest ammonium persulfate and the rest acrylic acid, and closing the kettle opening;
s30: stirring the mixture in a reaction kettle for 2-3min, and uniformly dripping the materials A and B;
s40: after the dripping is finished, preserving the heat for 1 to 1.5 hours at the temperature of between 36 and 40 ℃;
s50: adding all water, all sodium gluconate and all liquid alkali into a reaction kettle, stirring for 10-15min, and ending the reaction.
Preferably, the preparation method of the high water-reducing slump-retaining polycarboxylate superplasticizer comprises the following steps:
s10: adding 330 kg of TPEG, 200 kg of deionized water, 1.65 kg of ammonium persulfate and 7 kg of acrylic acid into a reaction kettle, and sealing the reaction kettle;
preparing the material A and uniformly mixing: 120 kg of deionized water, 20 kg of acrylic acid, 0.9 kg of mercaptopropionic acid and 4.5 kg of silane coupling agent;
preparing material B and uniformly mixing: 150 kg of deionized water and 1 kg of white hanging block;
s20: opening the reaction kettle at normal temperature, adding 1.65 kg of ammonium persulfate and 7 kg of acrylic acid, and closing the kettle opening after the addition;
s30: stirring the mixture in a reaction kettle for 2-3min, and uniformly dripping the materials A and B;
s40: after the dripping is finished, preserving the heat for 1 hour within the temperature range of 36-40 ℃;
s50: 116 kg of water, 20 kg of sodium gluconate and 20 kg of liquid alkali are added into the reaction kettle, and the reaction is finished after stirring for 10-15 min.
Preferably, in S30, the material a is added dropwise (180±10) min, and the material B is added dropwise (210±10) min.
Preferably, in the step S30, the stirring of the reaction kettle is continuously or halfway stopped in the process of dripping the material a and the material B.
As can be seen from the description of the invention, the polycarboxylic acid water reducer with high water reduction and slump retention provided by the invention is synthesized at normal temperature, has simple production process, excellent performance and high cost performance, and can simultaneously meet the requirements of high water reduction and slump retention.
Detailed Description
In order to make the technical problems, technical schemes and beneficial effects to be solved more clear and obvious, the invention is further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The polycarboxylate water reducer is usually a water reducer with controllable molecular chains, which is formed by polymerizing an unsaturated monomer and a polyether polyester macromonomer through free radicals, and has different molecular structures, and the water reducer has different dispersion performance and dispersion retention performance in cement. According to the invention, under an oxidation-reduction reaction system, isopentenol polyoxyethylene ether is taken as a large monomer, small molecules such as acrylic acid, a silane coupling agent and the like are added, and a chain transfer agent is used for regulating the molecular weight, so that the polycarboxylic acid water reducer with water reducing and slump retaining performances is synthesized, a large amount of carboxyl is provided for the molecules of the water reducer by adding the acrylic acid, and the initial water reducing rate of the water reducer is ensured. The silane coupling agent containing double bonds is a good chemical bond bonding monomer, the hydrolyzed silicic acid oligomer can be chemically bonded with silicate in cement to play a role in surface bonding stronger than adsorption, so that the anchoring capability is obviously improved, meanwhile, the organosilicon monomer containing double bonds with a large molecular size is prepared through hydrolysis reaction, and the prepared organosilicon monomer is used for a polycarboxylate water reducer synthesis system, so that the molecular size of the polycarboxylate water reducer is increased, the polycarboxylate water reducer is difficult to enter an intercalation structure of soil, the effects of resisting mud and slowing down consumption are achieved, and the dispersion retaining capability of the post-stage water reducer is ensured.
The embodiment synthesizes the polycarboxylic acid water reducer with high water reduction and slump retaining by adopting a free radical polymerization method, and the specific preparation steps comprise:
firstly, putting a certain amount of TPEG-2400 and water into a four-neck flask, and stirring until the TPEG-2400 and the water are completely dissolved;
secondly, slowly adding ammonium persulfate into the four-necked flask, and stirring for 20min;
thirdly, preparing an aqueous solution A material of acrylic acid, mercaptopropionic acid and a silane coupling agent according to a certain proportion. Preparing the aqueous solution B material of the hanging white block according to a certain proportion.
And fourthly, simultaneously dripping the material A and the material B into a four-neck flask, wherein the dripping time of the material A is 180min, the dripping time of the material B is 210min, preserving the heat for 1 hour after the dripping is finished, adding a certain proportion of liquid alkali to adjust the pH value to 5-6, and finally diluting the synthesized polycarboxylate superplasticizer to 40% of solid content.
Different synthesis conditions such as the consumption of Acrylic Acid (AA), the consumption of a Silane Coupling Agent (SCA), the consumption of mercaptopropionic acid, the reaction temperature and the like are adopted to prepare the high water-reducing slump-retaining polycarboxylate superplasticizer, and an optimal synthesis scheme is searched by a single factor experiment method.
The effect of the polycarboxylic acid water-reducing agent on the cement dispersing action with respect to the amount of different Acrylic Acid (AA) is as follows:
the basic formula is as follows: n (TPEG): n (AA): n (SCA) =1:2.3:0.3, initiator amount accounting for 0.8% of the mass of the macromer, where m ((NH 4) 2S2O 8): m (nahso2.hcho) =1.5:1, chain transfer agent amount accounting for 0.25% of the mass of the macromer, and reaction temperature is 36-40 ℃. The other factors are kept unchanged, and only the molar ratio of n (AA) to n (TPEG) (1.5, 1.8, 2.1, 2.4, 2.7 and 3.0 respectively) is changed to synthesize different polycarboxylate water reducers.
Through cement paste fluidity experiments, the influence of the polycarboxylic acid water reducer synthesized by different acrylic acid dosages on cement paste fluidity is compared, and the results are shown in table 1.
TABLE 1
As can be seen from Table 1, as the amount of acrylic acid increases, the initial paste fluidity tends to increase, and when the molar ratio of n (AA): n (TPEG) is 1.5, the cement dispersibility of the water reducing agent is poor, and when n (AA): n (TPEG) increases to 2.1, the cement initial paste fluidity increases greatly, and as the n (AA): n (TPEG) cement initial paste fluidity increases, the increase continues. However, when n (AA): n (TPEG) =2.7, the cement paste fluidity increases gradually. Then when n (AA): n (TPEG) =3.0, the initial fluidity of the cement paste does not substantially increase.
This is mainly because the acid-ether ratio is small, the carboxyl group content in the water-reducing agent is low, the cement dispersibility is poor, and the carboxyl group content in the water-reducing agent is gradually increased with the increase of the acid-ether ratio, and the cement dispersibility is enhanced. When the carboxyl content reaches a certain amount, the molecular chain of the polycarboxylate water reducer is sparse, the steric hindrance effect is small, and the phenomenon that the fluidity of cement initial paste is not increased or even reduced occurs.
To further characterize the cement dispersion retention properties of the synthesized polycarboxylate water reducer, the loss of fluidity over time of 1h and 2h of cement paste was observed.
From the experimental results, it can be seen that n (AA) n (TPEG) increased from 1.5 to 3.3, and that the cement paste dispersion retention property increased first and then decreased. When n (AA): n (TPEG) =2.4, the 2-hour time loss rate was 14.7%, reached the minimum value, and the 2-hour time loss rate increased significantly by continuing to increase the amount of acrylic acid.
In view of the above, the cement paste initial paste fluidity and the rate of loss of fluidity with time are considered to synthesize a water-reducing slump-retaining complex polycarboxylate water reducer, so n (AA): n (TPEG) =2.7 is selected as the optimal acid-ether ratio.
The effect of the polycarboxylate water reducers used in different amounts of Silane Coupling Agent (SCA) on the cement dispersion is as follows:
the optimized formula is as follows: n (TPEG): n (AA): n (SCA) =1:2.7:0.3, initiator amount accounting for 0.8% of the mass of the macromer, where m ((NH 4) 2S2O 8): m (nahso2.hcho) =1.5:1, chain transfer agent amount accounting for 0.25% of the mass of the macromer, and reaction temperature is 36-40 ℃. The other factors are kept unchanged, and only the molar ratio of n (SCA) to n (TPEG) (0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 respectively) is changed to synthesize different polycarboxylate water reducers. Through cement paste fluidity experiments, the influence of the polycarboxylic acid water reducer synthesized by different acrylic acid dosages on cement paste fluidity is compared, and the results are shown in Table 2:
TABLE 2
As can be seen from table 2, the initial paste fluidity of the synthesized polycarboxylate water reducer tends to be continuously increased with the increase of the amount of the silane coupling agent, but the increasing trend is to increase and then decrease. When n (SCA): n (TPEG) =0.1:1, the dispersibility of the synthesized polycarboxylate water reducer in cement is poor, and as n (SCA): n (TPEG) increases, the cement initial paste fluidity increases and the dispersibility increases. Continuing to increase the value of n (SCA): n (TPEG), the cement initial paste fluidity increases slowly or even decreases.
As can be seen from the above table, as n (SCA): n (TPEG) increases, the initial paste fluidity of the synthesized polycarboxylate water reducer tends to increase and then decrease, and when n (SCA): n (TPEG) =0.3, the initial paste fluidity of the synthesized polycarboxylate water reducer is 276mm at maximum, and as n (SCA): n (TPEG) continues to increase, the initial paste fluidity starts to decrease. The cement dispersion retention properties of the polycarboxylate water reducer increase and decrease with increasing n (SCA): n (TPEG) value. When n (SCA): n (TPEG) =0.3, the 2-hour cement paste fluidity loss rate was minimal with time.
Combining the initial paste fluidity and the loss of fluidity over time of the above cement paste, n (SCA): n (TPEG) =0.3 was selected as the optimum silane coupling agent amount.
The following concerns the effect of different amounts of mercaptopropionic acid (MPA) on the cement dispersion of polycarboxylate water reducers:
the optimized formula is as follows: n (TPEG): n (AA): n (SCA) =1:2.7:0.3, initiator amount accounting for 0.8% of the mass of the macromer, where m ((NH 4) 2S2O 8): m (nahso2.hcho) =1.5:1, chain transfer agent amount accounting for 0.25% of the mass of the macromer, and reaction temperature is 36-40 ℃. The flow properties of the polycarboxylic acid water reducer were affected by the cement paste fluidity versus the amount of the different mercaptopropionic acid (MPA) by adjusting the amount of the chain transfer agent mercaptopropionic acid (0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0,4% by mass of the macromonomer), respectively, and the results are shown in Table 3.
TABLE 3 Table 3
As can be seen from the above table, as the amount of the chain transfer agent increases, the initial fluidity of the cement paste increases and then decreases, which means that the chain transfer agent has different initial water reduction rates by controlling the molecular weight of the polycarboxylate water reducer. It can be seen that the initial fluidity of the synthesized polycarboxylate superplasticizer was maximized when M (MPA): m (TPEG) =0.25%.
Further examining the influence of the amount of the chain transfer agent on the cement dispersion retention property of the polycarboxylate water reducer, the experimental result shows that the cement dispersion retention property of the polycarboxylate water reducer is also increased and then decreased along with the increase of the chain transfer agent. The 2h cement paste flow rate loss rate was 19.7% when the amount of the chain transfer agent was 0.25% of the mass of the macromonomer, and 15.3% when the amount of the chain transfer agent was increased to M (MPA): m (TPEG) =0.3%, reaching the minimum. The chain transfer agent is continuously added, the flow rate loss rate is gradually increased, and the cement dispersion maintaining performance is deteriorated.
The above initial paste fluidity and the 2-hour cement paste fluidity loss with time were combined, and the chain transfer agent M (MPA): m (TPEG) =0.3% was selected as the optimum chain transfer agent amount.
The following concerns the effect of polycarboxylic acid water reducers of different oxidant to reductant mass ratios on cement dispersion:
the optimized formula is as follows: n (TPEG): n (AA): n (SCA) =1:2.7:0.3, initiator amount accounting for 0.8% of the mass of the macromer, where m ((NH 4) 2S2O 8): m (nahso2.hcho) =1.5:1, chain transfer agent amount accounting for 0.3% of the mass of the macromer, and reaction temperature is 36-40 ℃. Keeping other factors unchanged, researching the optimal mass ratio of the oxidant (ammonium persulfate) and the reducing agent (white suspending block) in the oxidation-reduction system, keeping the total initiator accounting for 0.8% of the total amount of the large monomers unchanged, adjusting the mass ratio of the oxidant ammonium persulfate and the reducing agent white suspending block (1.2, 1.35, 1.5, 1.65, 1.8 and 1.95 respectively), synthesizing different polycarboxylic acid water reducers, and comparing the influence of the polycarboxylic acid water reducers with the mass ratio of the oxidant and the reducing agent on the flow property of cement paste by the flow property of the cement paste, wherein the results are shown in table 4.
TABLE 4 Table 4
As can be seen from the above table, as m ((NH 4) 2S2O 8): m (NaHSO2.HCHO) increases, the initial net slurry fluidity of the synthesized polycarboxylate superplasticizer tends to increase and then decrease.
When m ((NH 4) 2S2O 8): m (nahso2.hcho) =1.65:1, the initial fluidity of the cement paste of the synthesized polycarboxylate water reducing agent is 273mm at maximum, and the initial fluidity of the cement paste starts to decrease as m ((NH 4) 2S2O 8): m (nahso2.hcho) continues to increase. The cement dispersion retention performance of the polycarboxylate water reducer is increased and then reduced with the increase of the mass ratio of the oxidant to the reducer. When the mass ratio of the oxidant to the reducing agent is 1.65:1, the loss rate of the fluidity of the cement paste after 2 hours is minimum.
And (3) combining the initial paste fluidity and the time-lapse loss of fluidity of the cement paste, and selecting the optimal initiator dosage which is 0.8% of the total amount of the initiator and the total amount of the large monomer, wherein the mass ratio of the oxidant to the reducer is 1.65:1, and the optimal oxidant and the reducer are used.
The cement paste fluidity and the loss of the fluidity with time are used for representing the water reducing and slump retaining performances of the polycarboxylate water reducer, and finally, an optimal synthesis scheme for synthesizing the high water reducing slump retaining polycarboxylate water reducer is determined:
n (TPEG): n (AA): n (SCA) =1:2.7:0.3, initiator amount accounting for 0.8% of the mass of the macromer, where m ((NH 4) 2S2O 8): m (nahso2.hcho) =1.65:1, chain transfer agent amount accounting for 0.3% of the mass of the macromer, and reaction temperature is 36-40 ℃.
The following pilot plant experimental data for the high water-reducing slump-retaining polycarboxylate water reducer 50L are table 5:
TABLE 5
In the experiment, the sodium gluconate is added to improve the product performance and the solid content of the product to about 40 percent.
Through the synthesis experiment, the 50L polycarboxylic acid water reducer with high water reduction and slump retaining performance is successfully synthesized, and the performance indexes are tested according to national standards GB8076-2008 and GB/T8077-2012 as shown in tables 6 and 7 (the doping amounts are 0.5 percent)
TABLE 6 homogeneity index
TABLE 7 concrete Performance index
From tables 5 and 6, the performance indexes of the self-made high water-reducing slump-retaining polycarboxylate water reducer product meet the national standard requirements.
In order to characterize the water reducing and slump retaining properties of the self-made polycarboxylate superplasticizer, cement mortar experiments are adopted to observe the initial mortar fluidity, fluidity 1h and time loss rate 2h of the self-made polycarboxylate superplasticizer PC01, the commercially available water reducing polycarboxylate superplasticizer PC02 and the pure slump retaining polycarboxylate superplasticizer PC 03. In the experiment, PC02 and PC03 are mixed in different proportions (8:2, 6:4, 4:6 and 2:8 are respectively expressed as PC04, PC05, PC06 and PC 07) and PC01, the solid content is diluted to 20%, the mixing amount of the water reducer is 1.0% of the mixing amount of the cementing material, and the experimental results are shown in the following table 8:
TABLE 8 comparison of the Performance of self-made Water reducing agent PC01 and commercially available Water reducing agent
As can be seen from table 8, the initial gum sand fluidity of the self-made water reducer PC01 is higher than that of the commercial water reducer PC03 and all the mixed water reducers, but lower than that of the commercial water reducer PC 02; the gum sand fluidity 2h time loss rate of the self-made water reducer PC01 is inferior to that of the commercial water reducer PC03 and the mixed water reducer PC07, so that the self-made water reducer PC01 is seen to have good water reducing and slump retaining performances.
The following relates to the application of the high water-reducing slump-retaining polycarboxylate water reducer in concrete:
because the construction method of the underwater pile foundation concrete is different from that of ordinary concrete, the concrete mixture is required to have good construction performance and fluidity retention capacity, and the polycarboxylic acid water reducer which is doped is required to have good adaptability, high water reduction rate and strong fluidity retention capacity. The experiment examines the adaptability of the self-made water reducer PC01 in the C30 underwater pile foundation concrete to different cements and sands.
Table 9.C30 underwater pile foundation concrete mix ratio
TABLE 10 self-made Water reducing agent PC01 concrete Performance
From tables 9 and 10, it can be seen that the self-made polycarboxylate water reducer PC01 has good workability and fluidity retention capability, and has good adaptability to various brands of cement, whether river sand or machine-made sand.
While the invention has been described above with reference to exemplary embodiments, it will be apparent that the invention is not limited to the above embodiments, but is intended to cover various insubstantial modifications, either as applying the inventive concepts and technical solutions to the method or as applying the inventive concepts and technical solutions directly to other applications without modification, within the scope of the invention.
Claims (7)
1. The preparation method of the high-water-reduction slump-retaining polycarboxylate water reducer is characterized by preparing materials according to the components of the high-water-reduction slump-retaining polycarboxylate water reducer and the parts by weight of the components, wherein the high-water-reduction slump-retaining polycarboxylate water reducer comprises the following components in parts by weight: 320-340 parts of TPEG, 450-490 parts of deionized water, 3.2-3.4 parts of ammonium persulfate, 33-35 parts of acrylic acid, 0.8-1 part of mercaptopropionic acid, 4.4-4.6 parts of silane coupling agent, 0.9-1.1 parts of sodium metabisulfite, 19-21 parts of sodium gluconate, 19-21 parts of liquid alkali and 110-120 parts of water; the silane coupling agent is a silane coupling agent containing double bonds; the molar ratio of acrylic acid to TPEG was 2.7:1, a step of; the molar ratio of silane coupling agent to TPEG was 0.3:1, a step of;
the method comprises the following steps:
s10: adding all TPEG (t-butyl alcohol), 40% -45% of deionized water, 48% -52% of ammonium persulfate and 18% -23% of acrylic acid into a reaction kettle, and sealing the reaction kettle;
preparing the material A and uniformly mixing: 23% -28% of deionized water, 57% -62% of acrylic acid, all mercaptopropionic acid and all silane coupling agents;
preparing material B and uniformly mixing: residual deionized water and all suspended white blocks;
s20: opening the reaction kettle under the normal temperature condition, adding the rest ammonium persulfate and the rest acrylic acid, and closing the kettle opening after the rest acrylic acid is added;
s30: stirring the mixture in a reaction kettle for 2-3min, and uniformly dripping the materials A and B;
s40: after the dripping is finished, preserving the heat for 1 to 1.5 hours at the temperature of between 36 and 40 ℃;
s50: adding all water, all sodium gluconate and all liquid alkali into a reaction kettle, stirring for 10-15min, and ending the reaction.
2. The method for preparing the high water-reducing slump-retaining polycarboxylate superplasticizer as claimed in claim 1, wherein the method comprises the following steps:
s10: adding 330 kg of TPEG, 200 kg of deionized water, 1.65 kg of ammonium persulfate and 7 kg of acrylic acid into a reaction kettle, and sealing the reaction kettle;
preparing the material A and uniformly mixing: 120 kg of deionized water, 20 kg of acrylic acid, 0.9 kg of mercaptopropionic acid and 4.5 kg of silane coupling agent;
preparing material B and uniformly mixing: 150 kg of deionized water and 1 kg of white hanging block;
s20: opening the reaction kettle at normal temperature, adding 1.65 kg of ammonium persulfate and 7 kg of acrylic acid, and closing the kettle opening after the addition;
s30: stirring the mixture in a reaction kettle for 2-3min, and uniformly dripping the materials A and B;
s40: after the dripping is finished, preserving the heat for 1 hour within the temperature range of 36-40 ℃;
s50: 116 kg of water, 20 kg of sodium gluconate and 20 kg of liquid alkali are added into the reaction kettle, and the reaction is finished after stirring for 10-15 min.
3. The method for preparing the high water-reducing slump-retaining polycarboxylate superplasticizer as claimed in claim 1, wherein in S30, A is added dropwise (180+ -10) min, and B is added dropwise (210+ -10) min.
4. The method for preparing the high water-reducing slump-retaining polycarboxylate superplasticizer as claimed in claim 1, wherein in the step S30, the reaction kettle is continuously or halfway stirred during the process of dropwise adding the material A and the material B.
5. The preparation method of the high water-reducing slump-retaining polycarboxylate superplasticizer as claimed in claim 1, wherein the mass ratio of mercaptopropionic acid to TPEG is 0.003:1.
6. the preparation method of the high water-reducing slump-retaining polycarboxylate superplasticizer as claimed in claim 1, wherein the mass ratio of ammonium persulfate to white hanging block is 1.65:1.
7. The preparation method of the high water-reducing slump-retaining polycarboxylate superplasticizer as claimed in claim 1, wherein the water-reducing polycarboxylate superplasticizer is characterized by comprising TPEG330, deionized water 470, ammonium persulfate 3.3, acrylic acid 34, mercaptopropionic acid 0.9, silane coupling agent 4.5, sodium metabisulfate 1, sodium gluconate 20, liquid alkali 20 and water 116.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110415153.2A CN114276499B (en) | 2021-04-17 | 2021-04-17 | High-water-reduction slump-retaining polycarboxylate superplasticizer and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110415153.2A CN114276499B (en) | 2021-04-17 | 2021-04-17 | High-water-reduction slump-retaining polycarboxylate superplasticizer and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114276499A CN114276499A (en) | 2022-04-05 |
| CN114276499B true CN114276499B (en) | 2024-01-12 |
Family
ID=80868493
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110415153.2A Active CN114276499B (en) | 2021-04-17 | 2021-04-17 | High-water-reduction slump-retaining polycarboxylate superplasticizer and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114276499B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106632881A (en) * | 2016-09-29 | 2017-05-10 | 湖北工业大学 | Low water-reducing and high slump loss resistant type polycarboxylate superplasticizer master batch |
| CN110759663A (en) * | 2019-10-23 | 2020-02-07 | 安徽海螺新材料科技有限公司 | Preparation method and application of anti-mud polycarboxylate superplasticizer |
| CN111620594A (en) * | 2020-06-23 | 2020-09-04 | 安徽海螺新材料科技有限公司 | Polycarboxylate superplasticizer and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111718447B (en) * | 2019-03-19 | 2021-12-03 | 江苏奥莱特新材料股份有限公司 | Fluorescent polycarboxylic acid water reducer and preparation method thereof |
-
2021
- 2021-04-17 CN CN202110415153.2A patent/CN114276499B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106632881A (en) * | 2016-09-29 | 2017-05-10 | 湖北工业大学 | Low water-reducing and high slump loss resistant type polycarboxylate superplasticizer master batch |
| CN110759663A (en) * | 2019-10-23 | 2020-02-07 | 安徽海螺新材料科技有限公司 | Preparation method and application of anti-mud polycarboxylate superplasticizer |
| CN111620594A (en) * | 2020-06-23 | 2020-09-04 | 安徽海螺新材料科技有限公司 | Polycarboxylate superplasticizer and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 高减水高保坍聚羧酸减水剂的合成与性能研究;周红;廖声金;王伟;;商品混凝土(第12期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114276499A (en) | 2022-04-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110845672B (en) | Polycarboxylic acid type concrete glue reducing agent and preparation method thereof | |
| CN105837763B (en) | Silane polycarboxylic acid water reducing agent and preparation method thereof | |
| CN108948288B (en) | Preparation method of crosslinking type polycarboxylate superplasticizer by adopting carboxyl functional monomer | |
| CN107777910B (en) | Normal-temperature early-strength polycarboxylate superplasticizer for prefabricated parts and preparation method thereof | |
| CN111944101A (en) | Preparation method of high-adaptability polycarboxylate superplasticizer suitable for low-quality aggregate | |
| CN106832154B (en) | A kind of thickening type function polycarboxylate water-reducer and preparation method thereof | |
| CN108409193A (en) | A kind of Machine-made Sand C120 super high strength concrete polycarboxylic admixtures and preparation method thereof | |
| CN104876468A (en) | Functionalized polycarboxylic acid water reducer matched with silica fume and preparation method thereof | |
| CN105585673B (en) | A kind of concrete sticking enhancing water-loss reducer and the preparation method and application thereof | |
| CN111019057B (en) | Viscosity-reducing polycarboxylate superplasticizer and preparation method thereof | |
| CN102503221B (en) | Cyclohexanol grafted polycarboxylic acid water reducing agent and preparation method thereof | |
| CN114349914B (en) | Ferrocene modified anti-mud polycarboxylate water reducer and preparation method thereof | |
| CN111154046A (en) | Polycarboxylate superplasticizer | |
| CN113444210B (en) | Low-sensitivity water-reducing slump-retaining polycarboxylic acid water reducer and preparation method thereof | |
| CN112194432B (en) | High-dispersion high-adhesion shield grouting material | |
| CN114230726A (en) | Polycarboxylate superplasticizer with strong adsorption and fast dispersion and preparation method thereof | |
| CN112979214B (en) | Polyether water-retaining agent, preparation method thereof and cement-based building material | |
| CN114276499B (en) | High-water-reduction slump-retaining polycarboxylate superplasticizer and preparation method thereof | |
| CN109320668B (en) | Viscosity-reducing polycarboxylate superplasticizer and preparation method thereof | |
| CN109762114B (en) | Early-strength viscosity-reduction type polycarboxylate superplasticizer containing double viscosity-reduction functional groups and preparation method thereof | |
| CN108892756B (en) | Preparation method of high-adaptability polycarboxylate superplasticizer based on 3000-molecular-weight polyether | |
| CN111087552A (en) | Synthetic method of polycarboxylic acid water reducer with high water reducing rate and mud resistance | |
| CN108084358B (en) | Preparation method of collapse-proof polycarboxylate superplasticizer | |
| CN115850603A (en) | Aromatic ring-containing end-capped polyether, preparation method thereof and application thereof in slump-retaining water reducer | |
| CN109535347B (en) | Preparation method of block water-retaining concrete admixture |
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 | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20220816 Address after: No. 8, Yuanxi Road, Nanshan Area, Petrochemical Park, Nanpu Town, Quangang District, Quanzhou City, Fujian Province, 362100 Applicant after: FUJIAN ROAD AND BRIDGE XIANGTONG BUILDING MATERIAL TECHNOLOGY CO.,LTD. Address before: 361101 room 304t, Xinye building, Pioneer Park, torch hi tech Zone, Xiamen City, Fujian Province Applicant before: Xiamen xinrunyan New Material Co.,Ltd. |
|
| TA01 | Transfer of patent application right | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |