Gypsum retarder is mainly used for plaster building materials such as plaster gypsum, bonded gypsum, gypsum putty, gypsum products, etc. It is mainly used to reduce the setting rate of gypsum.

There are three main types of retarders commonly used: organic acids and their soluble salts, alkaline phosphates, and proteins. Organic acid and its soluble salt retarders mainly include citric acid, sodium citrate, tartaric acid, potassium tartrate, acrylic acid and sodium acrylate, etc. Among them, citric acid and its salts are the most studied. Citric acid and its salt can achieve a strong retarding effect when the dosage is very small. Phosphate retarders mainly include sodium hexametaphosphate and sodium polyphosphate.

Performance: Gypsum retarder is white, brown, powdery, and soluble in water.

Light color: yellow powder

Density: about 380kg/m³—500kg/m³