Hydroxypropyl methyl cellulose is generally used in degreasing coating/wall putty with a viscosity of 100,000, while cement mortar has relatively high requirements for viscosity, and it is better to choose a viscosity of 150,000. The most important role of hydroxypropyl methyl cellulose is water retention, followed by thickening. Therefore, in putty powder, as long as the water retention is achieved, the viscosity is lower. Generally speaking, the higher the viscosity, the better the water retention, but when the viscosity exceeds 100,000, the viscosity has little effect on the water retention.
Hydroxypropyl methyl cellulose is distinguished by viscosity, generally divided into the following types:
Low viscosity: 400-viscosity cellulose, mainly used for self-leveling mortar.
It has low viscosity and good fluidity. After adding, it will control the water retention of the surface, the bleeding is not obvious, the shrinkage is small, the cracking is reduced, it can also resist sedimentation, and enhance the fluidity and pumpability.
Medium and low viscosity: cellulose with a viscosity of 20,000 to 50,000, mainly used in gypsum products and joint fillers.
The viscosity is low, the water retention is reached, the workability is good, and the amount of water added is small.
Medium viscosity: 75,000 to 100,000 viscosity cellulose, mainly used for degreasing coating/wall putty, tile glue
Moderate viscosity, good water retention, good construction drape
High viscosity: 150,000-200,000, mainly used for EIFS&ETICS, thermal insulation mortar, vitrified microbead thermal insulation mortar
High viscosity, high water retention, mortar is not easy to fall ash, sag, improve construction.