Sodium Naphthalene Sulfonate

1. SNF superplasticizer is widely used in the construction industry to prepare free-flowing and pumpable concrete mixtures, also can be used as a raw material for composite accelerator, antifreeze and retarder in different construction industries.
2. Poly naphthalene sulfonate PNS can be used to improve the rheological and mechanical properties of concrete. For example, by dispersing cement particles and destroying cement agglomerates, the use of water is reduced, the water-cement ratio is reduced by up to 30%, which is especially necessary in the case of high-strength concrete.
3. Naphthalene sulfonic acid can be used in the prestressed components and high-range concrete for the construction of highways, bridges, tunnels, water conservancy and hydropower projects, ports, wharves, skyscrapers, power engineering, industrial and civil buildings.
4. Naphthalene based superplasticizer is suitable for many types of concretes. Including high-strength concrete, high-performance concrete, steamed concrete, large-fluid concrete, pumped concrete, etc.
5. Meanwhile, naphthalene sulphonate is also widely used in agriculture, plastics, rubber, papermaking, construction, textile, petroleum and other industries.
6. Polynaphthalene sulfonate is an anionic surfactant, its molecular chain length is between small molecules and macromolecules, and the degree of polymerization is about 7-15, that is, the molecular weight of its molecules is not uniform, it is two kinds of small molecules the condensate. It doesn’t affect the setting time of concrete, has low air entrainment, and can greatly reduce the water-cement ratio of concrete. Therefore, under the condition that the workability of the concrete is not affected, the high grade concrete with fluidity can be prepared.

When using porous aggregate, it is advisable to add water and stir first, then add naphthalene sulfonate formaldehyde water reducing agent.

When the slump is large, the vibrating time should not be too long to prevent bleeding and stratification.

It can be used after being formulated into a solution of the concentration.

SNF powder can be used directly, or it can be added after the cement aggregate is fully moistened with 60% mixing water.

The sulphonated naphthalene formaldehyde superplasticizer has good adaptability with other concrete chemical admixtures. It can be widely used as the composition of composite additives, and compounded into special functional additives, such as pumping agent, waterproofing agents, air-entraining water reducer admixtures, antifreeze agent, etc.

Naphthalene-based superplasticizer can be divided into high-concentration PNS with NaSO4 content<5% and low concentration PNS with Na2SO4 content>5%. When mixing concrete on construction site, powder admixture is generally added, and the content of Na2SO4 has little effect. The naphthalene sulfonate for sale in our company includes SNF-A, SNF-B, SNF-C with different Na2SO4 content.

• Increasing the content of Na2SO4 in the concrete naphthalene superplasticizer can improve the fluidity of the cement paste, increase the compressive and flexural strength of the concrete, the resistance to chloride ion penetration, and the resistance to carbonization. But it will adversely affect the shrinkage and deformation properties of concrete.
• With the increase of sodium sulfate content in naphthalene-based water reducing agent, the corresponding dispersibility will decrease, and the compressive strength of concrete at different ages will decrease.
• Excessive incorporation of Na2SO4 will increase the alkali content in the concrete, accelerate the hydration, hardening and water loss in the cement paste, generate greater restraint stress and weaken the crack resistance. The incorporation of sodium sulfate will accelerate the hydration rate of cement, release a large amount of heat of hydration quickly and concentratedly, which leads to an increase in internal temperature, causes greater temperature stress and cracks.
• The content of Na2SO4 within a certain range(3%-19%) can improve the fluidity of the cement paste. If it exceeds this range, the fluidity will drop sharply.
• Under the premise of a certain amount of water reducing agent, adding sodium sulfate can increase the early strength of concrete, but the strength growth rate after 28d will decrease.
• As the content of sodium sulfate increases, the early drying shrinkage of concrete increases significantly. At 28d, the effect of sodium sulfate content on the drying shrinkage of concrete varies. Among them, when the Na2SO4 content is 10%, the drying shrinkage value of concrete reaches the maximum.
• The cracking property of concrete gradually increases with the increase of Na2SO4 content, and the crack width shows an increasing trend.
• When the Na2SO4 content is increased in a lower range, the ability of concrete to resist carbonization and chloride ion penetration can be improved.

Naphthalene based superplasticizer are generally produced from industrial naphthalene, sometimes refined naphthalene. The production process is as follows. Naphthalene is sulfonated, hydrolyzed, condensed, neutralized, filtered and spray-dried to get powdery sodium naphthalene sulfonate. The production of SNF superplasticizer is mature and its performance is stable.

The concrete water reducer can be used directly in concrete, and the effect of over-mixing or under-mixing on concrete performance can be predictable. In addition, naphthalene based superplasticizer has good adaptability with other admixtures and can be widely used as the composition of composite admixtures, such as, pumping agents, waterproofing agents, air entraining water reducing agents and antifreeze agents, etc.