Gypsum boards are produced from gypsum plaster, water and additives for the gypsum core as well as cardboard on continuous conveyor lines.
Prior to diving into the chemistry of gypsum additives, a few basic principles of gypsum chemistry have to be recaptured. The chemical reaction of gypsum binder with water is a solution and precipitation process. The crystallization of gypsum follows the law of nucleation and crystal growth. The hydration of calcium sulphate hemihydrate to gypsum can be described with the equation
CaSO4 0.5 H2O + 1.5 H2O --> CaSO4 2 H2O (1)
Numerous partly desired...