Putty powder is generally 100,000 yuan, and the requirements for mortar are higher, and 150,000 yuan is required for easy use. Moreover, the most important function of HPMC is water retention, followed by thickening. In the putty powder, as long as the water retention is good and the viscosity is low (70,000-80,000), it is also possible. Of course, the higher the viscosity, the better the relative water retention. When the viscosity exceeds 100,000, the viscosity will affect the water retention. Not much anymore.

What is the main function of the application of HPMC in putty powder, and does it happen chemically?

In the putty powder, HPMC plays three roles of thickening, water retention and construction. Thickening: Cellulose can be thickened to suspend and keep the solution uniform up and down, and resist sagging. Water retention: make the putty powder dry slowly, and assist the ash calcium to react under the action of water. Construction: Cellulose has a lubricating effect, which can make the putty powder have good construction. HPMC does not participate in any chemical reactions, but only plays an auxiliary role. Adding water to the putty powder and putting it on the wall is a chemical reaction, because new substances are formed. If you remove the putty powder on the wall from the wall, grind it into powder, and use it again, it will not work because new substances (calcium carbonate) have been formed. ) too. The main components of ash calcium 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 ash calcium in water and air Under the action of CO2, calcium carbonate is generated, while HPMC only retains water, assisting the better reaction of ash calcium, and does not participate in any reaction itself

The relationship between the viscosity and temperature of HPMC, what should be paid attention to in practical application?

The viscosity of HPMC is inversely proportional to temperature, that is, the viscosity increases as the temperature decreases. The viscosity of a product we usually refer to refers to the test result of its 2% aqueous solution at a temperature of 20 degrees Celsius.

In practical applications, it should be noted that in areas with large temperature differences between summer and winter, it is recommended to use a relatively low viscosity in winter, which is more conducive to construction. Otherwise, when the temperature is low, the viscosity of the cellulose will increase, and the hand feel will be heavy when scraping.

Medium viscosity: 75000-100000 mainly used for putty
Reason: good water retention