Cellulose ethers

Powdered cellulose ethers are the main modifying additives in almost all types of dry building mixtures, due to their ability to retain water in the mass of the solution, in particular, to slow down the rapid transition of water into the absorbent base.

Already in a low concentration (usually: 0.1 - 0.5%), they allow you to control the properties of mortars based on cement, gypsum, latex and other binders.
The introduction of cellulose ethers into building mixtures allows:

improve their consistency, ease of laying and stability, achieve uniform adhesion
improve the adhesive properties of the mortar
increase the open time, while maintaining a plastic consistency
achieve high mortar strength