CN-121990781-A - Low-carbon cement performance improver and preparation method and application thereof

CN121990781ACN 121990781 ACN121990781 ACN 121990781ACN-121990781-A

Abstract

The application relates to the technical field of cement additives, in particular to a low-carbon cement performance improver and a preparation method and application thereof. The modifier is prepared by compounding a component A, a component B and a component C according to a specific proportion, wherein the component A is a quaternary ammonium-quaternary phosphonium biscationic polymer, the component B is an esterified copolymer containing phosphoryl groups and hydrophobic ends, and the component C is an environment-friendly nonionic surfactant. The application forms a multiple mechanism of adsorption-anchoring-steric hindrance-compatibility by the synergistic effect of three components, effectively solves the problems of high adsorptivity and quick fluidity loss of low-carbon cement, and the modifier provided by the application is applied to the preparation of low-carbon cement, obviously improves the initial dispersibility and fluidity retention rate of the mortar, overcomes the incompatibility problem of a cation-anion compound system, has high stability, small required addition, controllable cost, environmental protection and no degradation of cement strength, is mature in preparation process, is suitable for industrial production, and has obvious economic and environmental protection benefits.

Inventors

LAI HUAZHEN
WANG ZHAOPENG
ZHAO HUI
CHEN HAO
GUO YUANQIANG
FANG YUNHUI
ZHANG YULIN
CHEN WENSHAN

Assignees

科之杰新材料集团有限公司

Dates

Publication Date: 20260508
Application Date: 20251223

Claims (10)

1. The low-carbon cement performance improver is characterized by comprising a component A, a component B and a component C; the mass ratio of the component A to the component B is 1 (10-100), and the addition amount of the component C is 0.2% -1.5% of the total dry basis mass of the component A and the component B; The component A is a quaternary ammonium-quaternary phosphonium biscationic polymer prepared by reacting a water-soluble polymer with a polymethyl quaternary phosphonium salt, wherein the water-soluble polymer is a water-soluble polymer with a main chain of olefin polymer and a side chain containing tertiary amine groups; the component B is an esterified copolymer prepared by esterification of a carboxyl-containing polymer and an ether macromonomer, wherein the ether macromonomer comprises a polyether macromonomer and a polyoxyethylene ether macromonomer, the polyether macromonomer is a polyether macromonomer with a phosphoryl group at the tail end, and the polyoxyethylene ether macromonomer is a polyoxyethylene ether macromonomer with a C8-C22 hydrocarbon-based hydrophobic end; the component C is an environment-friendly nonionic surfactant, and the environment-friendly nonionic surfactant is an alkyl glycoside compound containing polyhydroxy structures.
2. The low carbon cement performance improver according to claim 1, wherein: the mass ratio of the polyhydroxy methyl quaternary phosphonium salt to the water-soluble polymer is (2-4) 10; the water-soluble polymer is one or two of poly (N, N-dimethylallylamine) and poly (dimethylaminoethyl methacrylate), and the weight average molecular weight of the water-soluble polymer is 3000-30000; the polyhydroxy methyl quaternary phosphonium salt is one or two of tetramethyl phosphonium sulfate and tetramethyl phosphonium chloride.
3. The low carbon cement performance improver according to claim 1, wherein: the water-soluble polymer is poly (N, N-dimethylallylamine), and the weight average molecular weight of the water-soluble polymer is 8000-15000.
4. The low carbon cement property improver according to claim 1, wherein the total mass of the ether-based macromonomer is the sum of the mass of the polyether-based macromonomer and the mass of the polyoxyethylene ether; the mass ratio of the polyether macromonomer to the polyoxyethylene ether is (1.2-2.5): 1; the mass ratio of the total mass of the ether macromonomer to the carboxyl group-containing polymer is (10-20): 1.
5. The low carbon cement performance improver according to claim 1, wherein: The carboxyl-containing polymer is at least one of polyacrylic acid, polymethacrylic acid and acrylic acid-maleic anhydride copolymer, and the weight average molecular weight of the carboxyl-containing polymer is 2000-15000; the polyether macromonomer is polyethylene glycol phosphate, and the weight average molecular weight of the polyether macromonomer is 400-2000; the polyoxyethylene ether macromonomer is one or two of alkylphenol ethoxylates and fatty alcohol ethoxylates, and the weight average molecular weight of the polyoxyethylene ether macromonomer is 400-2500.
6. The low carbon cement performance improver of claim 1, wherein the environmentally friendly nonionic surfactant is an alkyl glycoside.
7. A method of preparing the low carbon cement property improving agent as claimed in any one of claims 1 to 6, comprising the steps of: Dissolving a water-soluble polymer in water, slowly dropwise adding a polymethylphosphate aqueous solution for 1-2 hours at a temperature of 40-50 ℃, heating to 60-75 ℃ after the dropwise adding is finished, and continuously reacting for 1-3 hours to obtain a quaternary ammonium-quaternary phosphonium biscationic polymer aqueous solution, thus obtaining the component A aqueous solution; The preparation method comprises the steps of (1) in the presence of a catalyst, carrying out esterification reaction on a carboxyl-containing polymer, a polyether macromonomer and a polyoxyethylene ether macromonomer for 3-8 hours at 100-130 ℃, and adding water for dissolution after the reaction is finished to obtain an esterified copolymer aqueous solution, thus obtaining the component B aqueous solution; And (3) compounding, namely adding the component C into the esterified copolymer aqueous solution under the stirring condition, uniformly mixing, slowly adding the quaternary ammonium-quaternary phosphonium double-cation polymer aqueous solution, and fully stirring to obtain the low-carbon cement performance improver.
8. The method of manufacturing according to claim 7, wherein: the catalyst is p-toluenesulfonic acid.
9. The use of a low-carbon cement property improver in low-carbon cement, characterized in that the low-carbon cement property improver is as set forth in any one of claims 1 to 6.
10. The method according to claim 9, wherein the performance modifier is added to the low-carbon cement in an amount of 0.05-0.2% by mass of the cement based on the dry matrix.

Description

Low-carbon cement performance improver and preparation method and application thereof Technical Field The application relates to the technical field of cement additives, in particular to a low-carbon cement performance improver and a preparation method and application thereof. Background With the deep implementation of the "two carbon" strategy, the development and application of low carbon cements (such as calcined clay cements, limestone powder portland cements, etc.) has become a necessary trend in the building material industry. The low-carbon cement generally adopts calcined clay, limestone powder and other auxiliary cementing materials to replace part of cement clinker so as to reduce carbon emission in the production process. However, these auxiliary gelling materials have the characteristics of large specific surface area, high surface energy, complex chemical composition and the like, so that the auxiliary gelling materials have extremely strong adsorption capacity on traditional chemical additives (especially main-stream polycarboxylic acid water reducer), thereby causing two main core problems: The dispersibility problem is that after the traditional water reducer molecules are adsorbed in a large quantity rapidly, the sufficient depolymerization of cement particles cannot be effectively realized, so that the water demand of low-carbon cement is increased by 15% -25% compared with that of ordinary cement, and even if the water cement ratio is improved, the initial fluidity is still difficult to meet the construction requirement; Secondly, the fluidity loss is fast with time, and because the active adsorption sites of the auxiliary cementing material are saturated and occupied in a short time, the fluidity retention rate of the low-carbon cement is very lower than 65% in 30 minutes, and the construction window period is compressed to be less than 20 minutes, so that the construction requirements of pouring, vibrating and the like cannot be met. The main solution to the problems in the prior art is to simply increase the mixing amount of the water reducer, and when the mixing amount of the water reducer is increased to more than 0.5%, the initial dispersing effect can be barely improved, but the main solution has the obvious defects that on one hand, the production cost of building materials is greatly increased, on the other hand, excessive anionic polycarboxylic acid molecules cannot be effectively anchored due to the electrostatic repulsive effect of the surfaces of cement particles, so that the dispersing efficiency is not increased, and the performance defect of low-carbon cement is difficult to fundamentally solve. In addition, in the prior related technical scheme, as in the Chinese patent application with the publication number of CN119751761A, the disclosed organic-inorganic binary copolymerization system depends on beta-cyclodextrin steric hindrance and polyoxometallate nano structure, only solves the problem of adsorption resistance and cannot consider both fluidity maintenance and system stability, the Chinese patent application with the publication number of CN119798557A discloses a bio-based single component, the core is a beneficial adsorption + space crossover network, the dispersion and fluidity maintenance of the heavy clay are realized, but the three components of cation-anion-nonionic are lacked, the synergistic effect is limited, the Chinese patent application with the publication number of CN120248243A discloses a diblock monomer copolymerization system, the mud resistance and the dispersibility are improved through a ring side chain, but the compatibility and the anchoring synergistic effect of the compound system are not realized, and the complex component environment of low-carbon cement is difficult to adapt. Therefore, developing a performance improver which can effectively solve the problems of high adsorptivity and quick fluidity loss of low-carbon cement, has controllable cost and good stability becomes a technical requirement to be solved in the field. Disclosure of Invention The application aims to overcome the defects of the prior art, and aims to solve the problems of strong adsorption of low-carbon cement to water reducer, quick loss of fluidity, high cost and limited effect of the prior art scheme, through the synergistic effect of the specific three components and the optimized compounding process, the high-efficiency improvement of the dispersion performance of the low-carbon cement and the long-acting maintenance of the fluidity are realized, and meanwhile, the stability of the system is ensured, so that the method is suitable for industrial production. The application provides a low-carbon cement performance improver, which has the following technical scheme: The modifier comprises a component A, a component B and a component C, wherein the mass ratio of the component A to the component B is 1 (10-100) and the component C is 0.2-1.5% of the total dry basis ma