What are the main technical indicators of Hydroxypropyl Methyl Cellulose (HPMC)
Hydroxypropyl content and viscosity, most users are concerned about these two indicators. With high hydroxypropyl content, water retention is generally better. Large viscosity, water retention, relatively (but not absolute) is better, and high viscosity, better use in cement mortar.
What are the main raw materials of hydroxypropyl methylcellulose (HPMC)?
The main raw materials of hydroxypropyl methylcellulose (HPMC): refined cotton, methyl chloride, propylene oxide, and other raw materials, such as lye, acid, toluene, isopropyl alcohol, etc.
What is the application of HPMC in putty powder? Does it occur chemistry?
HPMC plays three roles in thickening, water retention and construction in the putty powder. Thickening: Cellulose can be thickened to suspend, keep the solution uniform and consistent, and resist sagging. Water retention: make the putty powder dry more slowly, and help the gray calcium react under the action of water. Construction: Cellulose has a lubricating effect, which can make putty powder have good construction properties.
HPMC does not participate in any chemical reaction, only plays a supporting role. Putting water on the wall and putting it on the wall is a chemical reaction. Because there is a new substance generated, the putty powder on the wall is removed from the wall, ground into powder, and then used, it will not work because a new substance (calcium carbonate) has been formed. ).
The main components of gray 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 Under the action of CO2, calcium carbonate is formed, while HPMC only retains water and assists the better response of gray calcium, which itself does not participate in any reaction.