HPMC plays three roles in water retention, thickening and construction in putty powder.
1. Thickening: Cellulose can thicken, keep the solution uniform and consistent, and resist sagging.
2. Water retention: Make the putty powder dry slowly, and assist the ash calcium to react under the action of water.
3. Construction: cellulose has a lubricating effect, which can make the putty powder have good construction.
HPMC does not undergo any chemical reactions and only plays an auxiliary role. Adding putty powder to water on the wall is a chemical reaction, because new substances are formed,
The relationship between the viscosity of HPMC and temperature, the viscosity of HPMC is inversely proportional to the temperature, the viscosity increases with the decrease of temperature, we usually say the viscosity of a product refers to the detection of 2% aqueous solution at a temperature of 20 degrees Celsius result. In practical applications, it should be noted that in areas with large temperature differences between summer and winter, it is recommended to use products with relatively low viscosity in winter, which is more conducive to construction. Otherwise, when the temperature is low, the viscosity of cellulose will increase, and the hand feeling will be heavy when scraping. The medium viscosity of 75000-100000 is mainly used for putty. The reason: good water retention and high viscosity.
