Essential information
| Chinese name | 减水剂 | Advantage | Reduce unit cement consumption and save cement |
| Foreign name | water-reducing admixture | Usefulness | Concrete admixtures |
| CAS No. | 1561-92-8 | formula | C4H7NaO3S |
Basic introduction
English name: water reducing administration, water reducer, plasticizer
The appearance is divided into water and powder. The solid content of water agent is generally 20%, 40% (also called mother liquor), 60%, and the solid content of powder agent is generally 98%.
According to the water reducing and strengthening capacity of water reducing agents, they are divided into ordinary water reducing agents (also known as plasticizers, with a water reducing rate of no less than 8%), high performance water reducing agents (also known as superplasticizers, with a water reducing rate of no less than 14%) and high-performance water reducing agents (with a water reducing rate of no less than 25%), and they are also divided into early strength type, standard type and retarding type.
It can be divided into:
(1) lignosulfonate; (2) Polycyclic aromatic salts; (3) Water soluble resin sulfonates.
Ordinary water reducing agent should be used for concrete with daily minimum temperature above 5 ℃. The superplasticizer should be used for concrete constructed at a daily minimum air temperature above 0 ℃, and is suitable for preparing high fluidity concrete, high strength concrete and steam curing concrete.
At present, several commonly used water reducing agents in the market are sodium lignosulfonate water reducing agent, naphthalene series superplasticizer, aliphatic superplasticizer, amino superplasticizer, polycarboxylic acid superplasticizer, etc.
Lignosulfonate: it is a common water reducing agent. Its raw material is lignin, which is generally extracted from coniferous wood. Lignin is polymerized from three kinds of lignin monomers, namely, oleoresin, coniferol and sinapinol. It can be used in mortar to improve workability and fluidity, improve strength, and reduce water by 5-10%.
Naphthalene sulfonate water reducer: it is the first highly effective water reducer used in China, which is the product of sulfonation of naphthalene with sulfuric acid and condensation with formaldehyde. It belongs to anionic surfactant. This type of water reducer can be light yellow to dark brown powder depending on the appearance of the product, and is easily soluble in water. It can disperse many powder materials such as cement well, with a water reduction rate of 25%.
Melamine series water reducer: it is the product of melamine sulfonated by sulfuric acid and condensed with formaldehyde, so its chemical name is sulfonated melamine formaldehyde resin, belonging to anionic surfactant. This kind of water reducing agent is white powder, easily soluble in water, well dispersed in powder materials, with high water reduction rate, and good fluidity and self repair performance.
Powder polycarboxylate: it is a new high-performance water reducing agent developed in recent years. It has excellent water reduction rate, fluidity and permeability. The strength of cement mortar is obviously enhanced, but the production process is complex and the price is generally high.
Casein: It is a kind of biopolymer, which is obtained after milk is precipitated with acid and dried in a cylinder.
polycarboxylates high performance water-reducing admixture
Polycarboxylic acid series high-performance water reducing agent is a kind of concrete superplasticizer (water reducing agent) with the most advanced technology content, the best application prospect and the best comprehensive performance in the world. Polycarboxylic acid series high-performance water reducing agent is a composite product of carboxylic acid type graft copolymer and other effective additives. The performance comparison with similar products at home and abroad shows that the polycarboxylic acid series high-performance water reducer has reached the international advanced level in terms of technical performance indicators and cost performance.
Scope of application
It is applicable to pumping or normal concrete works with strength grade of C15~C60 and above. It is especially suitable for preparing concrete projects with high durability, high flow state, high slump protection, high strength and high requirements for appearance quality. It is very beneficial for preparing high fluidity concrete, self compacting concrete and fair faced concrete.