The role of hydroxypropyl methyl cellulose in putty powder?

Hydroxypropyl methyl cellulose plays three roles in the putty powder: thickening, water retention and construction.

Thickening: Cellulose can be thickened to suspend, keep the solution uniform up and down, and resist sagging.

Water retention: make putty powder dry more slowly, and assist lime calcium to react under the action of water.

Construction: Cellulose can lubricate and make putty powder have good workability. Hydroxypropyl methylcellulose does not participate in any chemical reaction, only plays an auxiliary role. Adding water to the putty powder and putting it on the wall is a chemical reaction. Because of the formation of new substances, it is impossible to remove the putty powder from the wall, grind it into powder, and then reuse it, because a new substance (calcium carbonate) has been formed. The main components of calcium ash powder are: a mixture of Ca (OH) 2, CaO and a small amount of CaCO3. CaO+H2O=Ca (OH) 2-Ca (OH) 2+CO2=CaCO3 ↓+H2O calcium ash generates calcium carbonate under the action of CO2 in water and air, while hydroxypropyl methyl cellulose is only water retaining, which helps calcium ash react better and does not participate in any reaction itself.