Why Do You Need HPMC in Dry Mix Mortar?

HPMC is often used in dry mix mortar as water retention and thickening agent. It can increase the wet viscosity of fresh mortar and prevent segregation. Water retention is also important; as it allows the cementitions material to have more time to hydrate after the mortar has been applied. A significant increase in water retention can be achieved by adding a small amount of HPMC to the dry mix mortar. When the content reaches a certain level, the tendency to increase water retention slows down. As the ambient temperature increases, the water retention capacity of HPMC generally decreases. However, some modified HPMCs have better water retention capacity even at high temperatures. It also has air-entraining properties, which improve mortar’s workability by introducing fine air bubbles.