Anti-adsorption agent for concrete and its preparation method and process Hubei anti-segregation agent manufacturer

Polycarboxylate water-reducing agent is a new generation of high-performance water-reducing agent due to its low dosage, high water-reducing rate, good fluidity and slump retention of fresh concrete, With a series of outstanding properties such as low shrinkage and environmental friendliness, it has been widely used in municipal administration, railways, highways, ports, bridges, hydropower and other fields.

However, as the country attaches great importance to environmental protection work, environmental protection inspections have been continuously strengthened, especially special inspections of aggregates used in concrete. Aggregates are in short supply, and the quality of aggregates and powders fluctuates more and more. The supply of sand is very tight in many places. Due to restrictions on material conditions, sand and gravel resources in various places are gradually becoming scarce and deteriorating. The polycarboxylate water-reducing agent has a strong adsorption tendency on clay minerals or porous structure materials, and is sensitive to the soil and stone powder in concrete aggregates. The aggregate contains mud or stone powder, which will affect the dispersion performance of the water-reducing agent. Significantly reduced, which has a great impact on concrete transportation, working conditions and strength. When the mud or powder content in the concrete system is high, the carboxylic acid water-reducing agent shows insufficient water reduction rate and large slump loss. Therefore, how to solve the problem of the sensitivity of polycarboxylate water-reducing agents to the mud content of sand and gravel is an urgent problem that needs to be solved in the admixture industry.

Technical implementation elements:

In view of the shortcomings of the existing technology, the third aspect of this technology One purpose is to provide a method for preparing an anti-adsorbent for concrete, which enables the prepared anti-adsorbent for concrete to better absorb mud and stone powder in concrete and reduce the impact of the mud or powder content of sand and gravel on polycarboxylic acid. Advantages of water reducing agents.

The second purpose of this technology is to provide an anti-adsorption agent for concrete, which can reduce the mud content or powder content of sand and gravel and reduce the water content of polycarboxylic acid. Advantages of the effects of agents.

To achieve the first purpose above, this technology provides the following technical solutions:

A method for preparing an anti-adsorption agent for concrete, including the following steps:

s1. Add deionized water and the composition in a reaction vessel according to the mass ratio. a. Raise the temperature to 70℃-90℃ and form a premix after composition a is completely dissolved;

s2. Add initiator to the premix , and add composition b dropwise, and at the same time, add a mixed solution of reducing agent and chain transfer agent dropwise, keep warm and stir the reaction for 2-2.5h;

s3, After the reaction, add alkali solution dropwise to adjust the pH to 6-8 to obtain the anti-adsorption agent for concrete;

The mass parts of each component are as follows:

1-3 parts of deionized water;

10-30 parts of composition a;

10-30 parts of composition a;

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3-5 parts of initiator;

30-50 parts of composition b;

1-3 parts of reducing agent;

1-3 parts of chain transfer agent;

The composition a is mixed with one or more monomers a, and the molecular structure of the monomer a is as follows:

Wherein, r3 is alkenyl;

The composition b is composed of one or more monomers b mixed , the molecular structure of monomer b is as follows:

Wherein, r1 and r2 are saturated hydrocarbon groups or unsaturated hydrocarbon groups.

Using the above technical solution, a specific ratio of composition a and composition b are used to react to form an anti-adsorption agent for concrete, and the anti-adsorption agent for concrete is formed Adding it to concrete will help the concrete anti-adsorbent to better absorb the mud or stone powder in the concrete, making it less likely that the mud or stone powder in the concrete will combine with the polycarboxylate water-reducing agent to affect the performance of the polycarboxylate water-reducing agent. The effect is conducive to better improving the fluidity of mortar, making the slump of concrete lower, and making the compressive strength of concrete higher.

This technology is further configured as follows: in the step s2, the composition b and the mixed solution of the reducing agent and the chain transfer agent are slowly dripped, and the dripping time is 2-4h.

Adopting the above technical solution, by controlling the dripping time of composition b and the mixed solution of reducing agent and chain transfer agent, it is beneficial to composition a and composition b. React more fully, which is conducive to improving the conversion rate of the reaction, making the prepared anti-adsorbent for concrete have a better effect of reducing the adsorption of polycarboxylate water-reducing agent and mud or stone powder, which is conducive to better improving the flow of mortar. degree, making the slump of concrete lower and the compressive strength of concrete higher.

This technology is further configured as follows: the composition a is uniformly mixed with propylene sulfonic acid, methacrylic sulfonic acid and vinyl sulfonic acid.

Using the above technical solution, propylene sulfonic acid, methacrylic sulfonic acid and vinyl sulfonic acid are uniformly mixed to form composition a, which is conducive to enhancing the reaction and generating The anti-adsorbent for concrete reduces the adsorption effect of polycarboxylate water-reducing agent and mud or stone powder, so that the role of the water-reducing agent in concrete is less likely to be affected, which is conducive to better improving the fluidity of the mortar, making Concrete has lower slumpThe effect is conducive to better improving the fluidity of mortar, making the slump of concrete lower, and making the compressive strength of concrete higher;

2. By uniformly mixing propylene sulfonic acid, methacrylic sulfonic acid and vinyl sulfonic acid in a mass ratio of 5:3:2 to form composition a, it is beneficial to better enhance the anti-adsorption resistance of the concrete obtained by the reaction. The effect of the agent on reducing the adsorption of polycarboxylate water-reducing agent to mud or stone powder is beneficial to the polycarboxylate water-reducing agent to play a better role in concrete, making the fluidity of the mortar less susceptible to being affected, and is conducive to better reducing the The slump of concrete makes the compressive strength of concrete higher;

3. By using divinyl ether and ethyl vinyl ether in parts by mass Mix evenly at a ratio of 7:3 to form composition b, which is conducive to better enhancing the resistance of the anti-adsorbent in concrete generated by the reaction of composition a and composition b. The polycarboxylate water-reducing agent and the mud in the concrete or The effect of stone powder adsorption makes the function of polycarboxylate water-reducing agent in concrete less susceptible to influence, which is conducive to better improving the fluidity of mortar, conducive to better reducing the slump of concrete, and is conducive to better Improve the compressive strength of concrete significantly.

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