1. Lignosulfonate
It can be subdivided into three components: calcium lignosulfonate, sodium lignosulfonate, and magnesium lignosulfonate. The order decreases from calcium salt to magnesium salt, but Compatibility with Portland cement varies. The raw materials for production are paper-making waste liquids from wood, reed, bamboo, wheat straw, and rice straw.
2. Polyols
Can be subdivided into grain honey, grain calcium and oligomeric grain. The raw material for production is waste honey leftover from sugar cane or sugar beet grain production. Oligopolymer grains are intermediate products of dextrin or cellulose hydrolysis. Grain and honey have strong retarding properties.
3. Hydroxycarboxylate
Sodium humate produced from natural raw materials such as lignite and peat is a kind of common hydroxycarboxylate water-reducing agent. Due to various technical properties It is not as good as grain honey and oligopolymer grain, and is worse than lignosulfonate water-reducing agent. It is now rarely used. Sodium gluconate made of natural raw materials has strong retarding properties, but has the effect of reducing water and enhancing the 28d strength of concrete. It is a hydroxycarboxylate admixture currently widely used. </p