Concrete anti-segregation agent manufacturer-what is the principle of anti-segregation agent

Contents of this article

• The best formula for concrete anti-segregation agent?

• What kind of ingredients are used to retain water in superplasticizers?

• What is the principle of dissociation solution?

• Principles and parameters of release agents?

• How to solve concrete bleeding and segregation? What admixtures can be adjusted?

• How do free radicals work?

• Measures to prevent concrete segregation?

What is the best formula for concrete anti-segregation agent?

Concrete, as the largest building material, has developed rapidly. In recent years, high-strength and high-performance concrete has been widely used in engineering. The fluidity of concrete has developed from the previous 70~90mm to the current slump of 180~230mm. Some projects also use self-compacting concrete, and the pumping height is getting higher and higher. However, the fluidity and cohesion of concrete are often incompatible, that is, it is difficult for concrete to maintain high cohesion properties under large flow conditions. In this way, concrete that pursues high fluidity is prone to bleeding and segregation. Moreover, with the gradual depletion of river sand resources and mineral resources in my country, the gradation and fineness of river sand fluctuate greatly, ordinary manufactured sand with poor particle size is used on a large scale, the water retention of cement fluctuates, and high water reduction but The more sensitive polycarboxylic acid-type water-reducing admixtures are constantly being promoted, and the quality control of ready-mixed concrete is facing increasingly severe challenges. The existing concrete anti-segregation agents have a strong flocculation effect, which will cause the concrete to settle quickly and the concrete to lose its flow properties instantly, which is detrimental to the workability of concrete. For this reason, we propose an anti-segregation agent for concrete and its preparation method.

Technical implementation elements:

The purpose of the present invention is to provide an anti-segregation agent for concrete and a preparation method thereof to solve the existing concrete anti-segregation problems proposed in the above background technology. The strong flocculation effect of the agent will cause the concrete to settle quickly, causing the concrete to lose its flow properties instantly, which is detrimental to the workability of the concrete.

In order to achieve the above object, the present invention provides the following technical solution: an anti-segregation agent for concrete, the composition of the anti-segregation agent for concrete is as follows:

Fly ash 5- 15 parts, mineral powder 5-15 parts, steel fiber 1-2 parts, polyethylene glycol 1-2 parts, polyhydroxy acid water reducing agent 20-30 parts, tackifier 0.8-1.2 parts, coagulant 0.5- 0.9 parts, 200-300 parts of deionized water, several parts of liquid alkali, 5-10 parts of silicone monomer, 3-5 parts of oxidizing agent, and 1-3 parts of reducing agent.

Preferably, the organosilicon monomer is propyltrichlorosilane or vinyltrichlorosilane or fluorosilicone monomer or a mixture of the three.

Preferably, the coagulant is powdered sodium sulfate.

Preferably, the tackifier is PAM, and the PAM is moistened with methanol or ethanol, deionized water is added for stirring, and the mixture is heated to 55 degrees Celsius during stirring to prepare a solution with a concentration of 4%.

Preferably, the oxidizing agent is one or a mixture of hydrogen peroxide, ammonium persulfate, and potassium persulfate.

Preferably, the reducing agent is ammonium persulfate-anhydrous sodium bisulfite or ammonium persulfate-sodium hypophosphite.

Preferably, the alkali solution is sodium hydroxide.

Preferably, the preparation method of the concrete anti-segregation agent includes the following steps:

S1: Mixing: combine silicone monomer, deionized water, polyhydroxyacid water-reducing agent and polyethylene glycol are added into the reaction kettle for mixing;

S2: Oxidation: Stir until the mixture in step S1 is evenly mixed, and add oxidant for oxidation;

S3: Reduction: Add fly ash, mineral powder and steel fiber to the oxidized mixture in step S2, and then add the reducing agent;

S4: Neutralization: Add a tackifier to the reduced mixture in step S3 and coagulant, stir continuously until the mixture is uniform, and then add liquid caustic soda to adjust the pH so that the pH is between 7-9, and then the anti-segregation agent for concrete can be obtained.

Compared with the existing technology, the beneficial effects of the present invention are: the invention adds fly ash, mineral powder and steel fiber to the anti-segregation agent, which can not only improve the compressive strength of concrete, but also It can also effectively improve the working performance and stratification of concrete, improve the segregation resistance of concrete, and reduce the expansion and slump of concrete. PAM is used as a tackifier because PAM has more -NH2. The tackifier has good hydrophilicity, making the concrete hydrophilic, water-retaining, thickening, resistance-reducing and viscosity-increasing. Adding calcium sulfate as a setting accelerator can promote concrete water splashing, accelerate hardening, and promote condensation. The invention has wide sources of raw materials, low cost, green and environmental protection, and simple operation.

What kind of materials are used to retain water in water reducing agents?

Concrete admixtures are divided into three generations. The first generation of lignins is basically no longer used. The second generation of naphthalene admixtures has certain environmental pollution. The current market share is not large. The third generation polycarboxylate water-reducing agent is the mainstream in the market. The main production raw materials are macromonomers (polyether polyols), the raw materials of macromonomers are ethylene oxide, the raw materials of ethylene oxide are ethylene, the raw materials of ethylene… Wait, basically the entire production process is There are no three waste emissions.

This is why the country actively advocates the application and promotion of third-generation water-reducing agents.

There are also some small ingredients, such as vc, sodium gluconate, sugar, and maltodextrin.

Generally speaking, the current application of water reducing agents is conducive to energy conservation and emission reduction. Even if there are certain environmental hazards. It’s also a pros and cons.

What is the principle of dissociation solution?

Dissociation solution

Dissociation solution��The other 2% of oxygen is converted into oxygen free radicals. Because this substance is very active, it can interact with almost any substance, causing a series of chain reactions that are destructive to cells.

Under normal circumstances, cells will not be killed by this molecular killer. This is because our human cells contain a large number of antioxidants, the nemesis of oxygen free radicals, such as fat-soluble vitamin E. , water-soluble vitamin C and some enzymes, etc. These natural antioxidants can undergo a redox reaction with oxygen free radicals, so that oxygen free radicals can be completely eliminated. However, only under certain circumstances, oxygen free radicals can kill cells or even the body.

Measures to prevent concrete segregation?

Concrete segregation is a phenomenon in which the cohesion between the components of the concrete mixture is insufficient to resist the sinking of the coarse aggregate, and the components of the concrete mixture separate from each other, resulting in uneven internal composition and structure. The reasons for segregation may be improper pouring and vibration, the maximum particle size of the aggregate is too large, the proportion of coarse aggregate is too high, the content of cementitious materials and fine aggregate is low, and the density of coarse aggregate is too high compared with fine aggregate. Too big, or the mixture is too dry or too thin, etc. The tendency to segregation can be reduced by using mineral admixtures or air-entraining agents.

<img src="/upfile/202304/2023041334528065.jpg"/