Hydroxypropyl methyl cellulose HPMC for wall putty

HPMC plays the three roles of thickening, water retention and construction in putty powder. Thickening: Cellulose can be thickened to suspend, keep the solution uniform up and down, and resist sagging. Water retention: Make the putty powder dry slower and assist the gray calcium to react under the action of water. Construction: Cellulose has a lubricating effect, which allows the putty powder to have good construction properties. HPMC does not participate in any chemical reactions and only plays an auxiliary role. Adding water to the putty powder and applying it to the wall is a chemical reaction, because new substances are formed. If you remove the putty powder from the wall, grind it into powder, and then use it again, 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 Gray calcium is in water and air Under the action of CO2, calcium carbonate is generated, while HPMC only retains water to assist the gray calcium to react better, and does not participate in any reaction itself.