What is the choice of HPMC viscosity when producing putty powder dry mortar?

Methylcellulose MC and hydroxypropylmethylcellulose (HPMC) have stable chemical properties. mildew resistance and water retention, and are not affected by pH changes.

The viscosity can be used from 50,000 to 200,000, but in production.the higher the viscosity, the better. The viscosity is inversely proportional to the bond strength. The higher the viscosity, the smaller the strength.

Regarding the quality of cellulose, mainly viscosity, it can be tested using a rotational viscometer;or it can be compared by a simple method.

In the comparison, take 1 gram of cellulose of the same viscosity. add 100 grams of water, put it in a disposable cup, and pour it at the same time. Observe which one has faster dissolution speed, better transparency and better thickening effect. The better the transparency, the less impurities.

Used in the low-grade putty powder on the inner wall, it has a certain thickening and water retention effect, which can increase the leveling property. However, it cannot be used in waterproof putty and external insulation dry mix.
Because these celluloses react with cement, ash calcium powder, and gypsum powder, inorganic binders.

Many people think that these celluloses are alkaline, and generally cement and ash calcium powder are also alkaline. It is considered that it can be used in combination.but CMC and CMS are not single elements.

  The chloroacetic acid they use in the production process is acidic. The substances remaining in the process of producing cellulose react with cement and ash calcium powder. so they cannot be combined. Many manufacturers have suffered a lot of losses and should be taken seriously.