What are the common types of naphthalene-based water-reducing agents? What are their differences and advantages compared with polycarboxylate water-reducing agents?

1. Naphthalene series ordinary admixture. Naphthalene series ordinary admixtures refer to admixtures with general water-reducing and reinforcing effects. They are mainly used in home construction, decoration and infrastructure fields that do not have high requirements for concrete water-reducing performance.

2. Naphthalene series additives. Compared with ordinary admixtures, naphthalene-based admixtures have the characteristics of large water reduction and good reinforcing effect. They are the best-selling mainstream admixture category on the market today.

3. Naphthalene series retarding admixture. Compared with other admixtures, naphthalene series retarding admixtures not only have water reduction and strengthening functions, but also have a retarding effect. They are suitable for use in some projects that have special requirements for concrete solidification.

4. Naphthalene-based air-entraining admixture. Naphthalene-based air-entraining admixture is a functional admixture. In addition to reducing water and enhancing functions, it also has an air-entraining effect.

Polycarboxylate water-reducing agent is the third generation of high-efficiency water-reducing agent developed after the ordinary water-reducing agent represented by wood calcium and wood magnesium and the high-efficiency water-reducing agent represented by naphthalene series and melamine series. The advantages of performance water-reducing agents compared to naphthalene series are briefly summarized as follows:

1. The water-reducing rate of polycarboxylate water-reducing agents is significantly higher than that of naphthalene-series water-reducing agents. When the same water reduction is achieved, Under the condition of water reducing rate, the dosage of polycarboxylate water reducing agent is much lower than that of naphthalene series water reducing agent, and its water reducing rate can be as high as 45%.

　2. Naphthalene-based water-reducing agents generally have relatively large slump losses. Generally speaking, increasing the dosage will help reduce slump loss, but adding a little more naphthalene-based water-reducing agents Concrete is easy to segregate, so it is difficult to adjust if the material is not good. However, concrete prepared with polycarboxylate superplasticizer can still meet the pumping requirements after 1 hour.

3. As the dosage increases, the ultimate water-reducing rate of polycarboxylate water-reducing agent is much higher than that of naphthalene-based water-reducing agent. When the dosage of naphthalene-based water-reducing agent is around 2.0%, Basically reached the limit, which shows that polycarboxylate superplasticizer is more suitable for formulating low water-cement ratio high-strength concrete.

4. When the dosage is appropriate, the concrete prepared with polycarboxylate superplasticizer has excellent workability, no segregation or bleeding, and the concrete has a uniform appearance and color. When used to prepare high-grade concrete, the concrete has good cohesion and is easy to mix.

5. Polycarboxylate superplasticizer products have good stability, no stratification or precipitation occurs during long-term storage, and no crystallization occurs at low temperatures.

6. The production process of naphthalene-based water-reducing agents has certain pollution to the environment, while polycarboxylate water-reducing agents adopt an environmentally friendly and green synthetic production process, which can save cement, improve concrete performance, and promote green concrete. , Sustainable development of low-carbon concrete technology.

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