Hydroxypropyl methylcellulose is made from highly pure cotton fiber as raw material through special etherification under alkaline conditions. It is a white or yellowish powder, easily soluble in water, let me talk about the dissolution method of hydroxypropyl methylcellulose.
1. First of all, hydroxypropyl methylcellulose is mainly used as an additive for putty powder, mortar and glue, and when added to cement mortar, it can be used as a water-retaining agent and retarder to increase pumpability. Adding it to putty powder glue can be used as an adhesive to improve spreadability and prolong the use time. Let's take Qingquan cellulose as an example to explain the dissolution method of hydroxypropyl methylcellulose.
2. Ordinary hydroxypropyl methylcellulose is first stirred and dispersed with hot water, then stirred with cold water and cooled to dissolve.
Specifically: Take 1/5-1/3 of the required amount of hot water, stir until the added product is fully expanded, then add the remaining hot water, which can be cold water, or even ice water, and stir to a suitable temperature (10 ℃) to dissolve completely.
3. Organic solvent wetting:
Hydroxypropyl methylcellulose can be dissolved very well by dispersing or wetting with organic solvents and then adding or adding cold water. The organic solvent may be ethanol, ethylene glycol, or the like.
4. In case of agglomeration or wrapping during dissolution, it is caused by insufficient stirring or direct addition of common causes to cold water, and it should be stirred quickly.
5. If bubbles are generated during dissolution, it can be left to stand for 2-12 hours (the specific time depends on the consistency of the solution), vacuumize and pressurize, or add an appropriate amount of defoamer to remove.