All questions about Hydroxypropyl Methylcellulose(HPMC), all here!
All questions about Hydroxypropyl Methylcellulose(HPMC), all here!(2)
All questions about Hydroxypropyl Methylcellulose(HPMC), all here!(3)
12.What is the difference between the cold water soluble type and the hot soluble type of hydroxypropyl methyl cellulose?
–A: HPMC cold water fast dissolving type is treated with glyoxal surface treatment, it is rapidly dispersed in cold water, but not really dissolved, the viscosity comes up, then it is dissolved. The hot soluble type is not surface treated with glyoxal. If the amount of glyoxal is large, it will be dispersed quickly, but the viscosity will come up slowly, if the amount is small, it will be the opposite.
13.What is the smell of hydroxypropyl methyl cellulose (HPMC)?
–A: HPMC produced by the solvent method uses toluene and isopropyl alcohol as solvents, if the washing is not very good, there will be some residual smell.
14.How to choose the suitable hydroxypropyl methyl cellulose (HPMC) for different applications?
–A: For putty powder, the requirement is low, 100,000 viscosity is sufficient.
For mortar applications: higher requirements, high viscosity, 150,000 – 200,000 is better. For glue applications: fast dissolving products with high viscosity are required.
15.What are the causes of air bubbles in putty powder?
–A: HPMC plays three roles in putty powder: thickening, water retention and construction. It is not involved in any reaction.
Reasons for bubbles.
1. Too much water has been put in.
2. Scraping another layer on top before the bottom layer is dry is also prone to bubbling.
16.The relationship between the viscosity and temperature of HPMC, what should be noted in practical application?
–A: The viscosity of HPMC is not inversely proportional to the temperature, that is to say, the viscosity increases as the temperature decreases. When we refer to the viscosity of a product, we mean the result of testing a 2% aqueous solution at a temperature of 20 degrees Celsius. In practice, where there is a large temperature difference between summer and winter, it should be noted that it is recommended to use a relatively low viscosity in the winter months, which is more favourable for construction. Otherwise, the viscosity of the cellulose increases when the temperature is low, and the scraping will feel heavy.