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CN-121974595-A - High-solid-content polycarboxylate superplasticizer and preparation method thereof

CN121974595ACN 121974595 ACN121974595 ACN 121974595ACN-121974595-A

Abstract

The invention relates to the technical field of water reducer preparation, in particular to a high-solid-content polycarboxylate water reducer and a preparation method thereof. The preparation method comprises the steps of mixing tea polyphenol and inorganic base in an organic solvent under inert atmosphere and ice water bath conditions, heating, dropwise adding sulfonate monomers for nucleophilic ring-opening sulfonation reaction, separating and purifying to obtain a tea polyphenol-based polybasic sulfonic acid solubilizer, mixing and dissolving a polyether macromonomer and water, adding the solubilizer, then carrying out copolymerization reaction with an unsaturated monomer under the action of an initiator and a molecular weight regulator, and regulating pH after the reaction is finished to obtain the polycarboxylic acid water reducer with the solid content of 70% -80%. According to the invention, the tea polyphenol-based polybasic sulfoacid solubilizer is introduced, so that the viscosity of a high-solid-content system is effectively reduced, the problem of mutual restriction of solid content and viscosity in the traditional process is solved, and the obtained product has high water reduction rate, excellent slump retaining property and good storage stability.

Inventors

  • YU FEIYU
  • CHEN LIYUAN
  • GUAN MENGQIN
  • KANG XIANG
  • LI XIANGHE
  • GAN FUPING
  • LI WEITENG
  • YAO XIAOYANG
  • ZHU QIAOYONG
  • ZHANG JIAYAN

Assignees

  • 科之杰新材料集团有限公司

Dates

Publication Date
20260505
Application Date
20251202

Claims (10)

  1. 1. The preparation method of the high-solid-content polycarboxylate superplasticizer is characterized by comprising the following steps of: S1, under the inert atmosphere and ice water bath conditions, adding water, an organic solvent, tea polyphenol and inorganic alkali, uniformly stirring, heating, slowly dropwise adding a sulfonate monomer, and separating and purifying after the reaction is finished to obtain a tea polyphenol-based polybasic sulfonic acid solubilizer; S2, after uniformly mixing and dissolving the polyether macromonomer M and water, adding the prepared tea polyphenol based polybasic sulfoacid solubilizer, after uniformly mixing, dropwise adding the unsaturated monomer, the initiator aqueous solution and the molecular weight regulator aqueous solution, and after the reaction is finished, regulating the pH value of the system to obtain the high-solid-content polycarboxylic acid water reducer.
  2. 2. The preparation method according to claim 1, wherein in the step S1, the mass ratio of the tea polyphenol, the sulfonate monomer, the inorganic base and the organic solvent is 1 (1.8-5.0): 0.5-2.0): 5-10.
  3. 3. The method according to claim 1, wherein in the step S1, the sulfonate monomer is one or more of 1, 3-propane sultone, 1, 4-butane sultone and 2, 4-butane sultone.
  4. 4. The method according to claim 1, wherein in step S1, the inorganic base is potassium hydroxide or sodium hydroxide, and the organic solvent is tetrahydrofuran.
  5. 5. The preparation method of claim 1, wherein in the step S2, the mass ratio of the polyether macromonomer M, the tea polyphenol based polybasic sulfoacid solubilizer and the unsaturated small monomer is 200 (2-12): 10-45.
  6. 6. The method according to claim 1, wherein in the step S2, the polyether macromonomer M is one or more of 3-methyl-3-butene-1-polyethylene glycol, 2-methylallyl polyethylene glycol, ethylene glycol monovinyl polyethylene glycol ether and 4-hydroxybutyl vinyl polyoxyethylene ether having a molecular weight of 600 to 6000.
  7. 7. The method according to claim 1, wherein in the step S2, the initiator is a water-soluble inorganic peroxy initiator or a water-soluble redox initiation system; The water-soluble redox initiation system comprises an oxidant and a reducing agent, wherein the oxidant is selected from hydrogen peroxide or persulfate, and the reducing agent is selected from one or a combination of more of sodium metabisulfite, ascorbic acid, glucose or sodium bisulfate.
  8. 8. The method according to claim 1, wherein in the step S2, the molecular weight regulator is one or more of thioglycollic acid, mercaptopropionic acid, mercaptoethanol, isopropanol, sodium hypophosphite, trisodium phosphate, sodium formate, sodium acetate and dodecyl mercaptan; the unsaturated monomer is unsaturated carboxylic acid and/or unsaturated carboxylic anhydride, and the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is one or a combination of more of acrylic acid, methacrylic acid, itaconic acid, maleic anhydride, acrylic anhydride and itaconic anhydride.
  9. 9. The preparation method of the water-based composite material is characterized in that in the step S1, the temperature of the ice water bath is 0-5 ℃, the temperature is raised to 30-50 ℃ after the ice water bath is uniformly stirred, the time for slowly dropwise adding the sulfonate monomer is 0.5-2h, the reaction is continued for 12-20h after the dropwise adding is finished, and then the temperature is reduced for separation and purification; In the step S2, when the polyether macromonomer M is mixed and dissolved with water, the temperature is raised to 20-45 ℃, and then the temperature is regulated to the initial reaction temperature, wherein the initial reaction temperature is 5-60 ℃; the dropping time of the unsaturated monomer, the initiator aqueous solution and the molecular weight regulator aqueous solution is 0.5-2.0h, the reaction temperature is controlled at 5-60 ℃, the reaction is continued for 0.5-1.0h after the dropping is finished, and the pH value of the regulating system is regulated to 5-7 by alkali.
  10. 10. A high solid content polycarboxylate superplasticizer is characterized by being prepared by the preparation method of any one of claims 1-9.

Description

High-solid-content polycarboxylate superplasticizer and preparation method thereof Technical Field The invention relates to the technical field of water reducer preparation, in particular to a high-solid-content polycarboxylate water reducer and a preparation method thereof. Background Polycarboxylic acid high-efficiency water reducer has become the mainstream of current research and application due to its excellent performance and environmental friendliness. The performance of the concrete is influenced by the synthesis process, raw materials and the mixing ratio of concrete, and the solid content is a key index, so that the high solid content can obviously reduce the long-distance transportation cost and better meet the construction requirements of large-scale engineering. However, the solid content of the current commercial polycarboxylate water reducer is generally maintained at a lower level of 40% -50%, and the economical efficiency and the industrial application of the commercial polycarboxylate water reducer are severely restricted. The bottleneck is mainly caused by the technical problems of rapid increase of system viscosity along with polymerization, uneven dispersion and accumulation of reaction heat, easy initiation and polymerization risks, fluctuation of product quality, aggravation of load of a material conveying pump and hidden trouble of equipment damage. Therefore, development of a polycarboxylate water reducer with high solid content and low viscosity has become a key technical problem to be broken through in industry. In the prior art, although high-solid content polycarboxylate water reducers are reported, such as the invention patent with publication numbers of CN107721232A and CN105778014B, the solid content is still limited to 55% -65%, and the problem of high viscosity is not solved effectively. Therefore, there is still a need for a novel high solids content, low viscosity polycarboxylate superplasticizer and a method for preparing the same. Disclosure of Invention In order to solve the defects in the prior art, the preparation method of the high-solid-content polycarboxylate superplasticizer provided by the invention comprises the following steps: S1, under the inert atmosphere and ice water bath conditions, adding water, an organic solvent, tea polyphenol and inorganic alkali, uniformly stirring, heating, slowly dropwise adding a sulfonate monomer, and separating and purifying after the reaction is finished to obtain a tea polyphenol-based polybasic sulfonic acid solubilizer; S2, after uniformly mixing and dissolving the polyether macromonomer M and water, adding the prepared tea polyphenol based polybasic sulfoacid solubilizer, after uniformly mixing, dropwise adding the unsaturated monomer, the initiator aqueous solution and the molecular weight regulator aqueous solution, and after the reaction is finished, regulating the pH value of the system to obtain the high-solid-content polycarboxylic acid water reducer. In step S1, the mass ratio of the tea polyphenol to the sulfonate monomer to the inorganic base to the organic solvent is 1 (1.8-5.0) (0.5-2.0) (5-10). Further, in step S1, the sulfonate monomer is one or more of 1, 3-propane sultone, 1, 4-butane sultone and 2, 4-butane sultone. In step S1, the inorganic base is potassium hydroxide or sodium hydroxide, and the organic solvent is tetrahydrofuran. In the step S2, the mass ratio of the polyether macromonomer M to the tea polyphenol based polybasic sulfoacid solubilizer to the unsaturated small monomer is 200 (2-12) to 10-45. Further, in the step S2, the polyether macromonomer M is one or more of 3-methyl-3-butene-1-polyethylene glycol, 2-methylallyl polyethylene glycol, ethylene glycol monovinyl polyethylene glycol ether and 4-hydroxybutyl vinyl polyoxyethylene ether with molecular weight of 600-6000. Further, in the step S2, the initiator is a water-soluble inorganic peroxy initiator or a water-soluble redox initiation system; The water-soluble redox initiation system comprises an oxidant and a reducing agent, wherein the oxidant is selected from hydrogen peroxide or persulfate, and the reducing agent is selected from one or a combination of more of sodium metabisulfite, ascorbic acid, glucose or sodium bisulfate. Further, in step S2, the molecular weight regulator is one or more of thioglycollic acid, mercaptopropionic acid, mercaptoethanol, isopropanol, sodium hypophosphite, trisodium phosphate, sodium formate, sodium acetate and dodecyl mercaptan; the unsaturated monomer is unsaturated carboxylic acid and/or unsaturated carboxylic anhydride, and the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is one or a combination of more of acrylic acid, methacrylic acid, itaconic acid, maleic anhydride, acrylic anhydride and itaconic anhydride. Preferably, in the step S2, the total amount of water is such that the mass concentration of the solid polymer (copolymerization product) in the final product high-s