Dissolution Method and Precautions for HPMC

Hydroxypropyl methyl cellulose is almost insoluble in anhydrous ethanol and acetone. The aqueous solution is quite stable at room temperature and can gel at high temperature. Most of the Hydroxypropyl methyl cellulose on the market now belong to cold water (room temperature water, tap water) instant type. Cold water instant HPMC will be more convenient and safer to use. When HPMC needs to be added directly to the cold water solution after ten to ninety minutes to gradually thicken, if it is a special model, you need to use hot water to stir and disperse first, then into the cold water after cooling can be dissolved.

HPMC products added directly to water will produce coagulation, then dissolve, but this dissolution is very slow and difficult. The following three dissolution methods are suggested, users can choose the most convenient method according to the use situation (mainly for cold water instant HPMC).

1、Cold water method: When it needs to be added directly to room temperature aqueous solution, it is better to use cold water dispersion type, after adding viscosity, consistency slowly increase to the index requirements.

2, powder mixing method: HPMC powder particles with equal or greater amounts of other powdered ingredients, through dry mixing to fully disperse, after adding water to dissolve, then the HPMC can be dissolved at this time, and not cohesive. In fact, no matter which type of hydroxypropyl methyl cellulose. It can be directly dry mixed into other materials.

3, organic solvent wetting method: HPMC with organic solvents, such as ethanol, ethylene glycol or oil pre-dispersion or wetting, and then add water to dissolve, then HPMC can also be smoothly dissolved.

In the dissolution process, if you encounter the phenomenon of lumps, it will be wrapped, which is the result of uneven stirring, so you need to speed up the speed of stirring, if the dissolution of air bubbles, is due to the stirring of air, the solution is left for 2-12 hours (the specific time by the solution consistency) or vacuum, pressure and other methods to remove, adding the appropriate amount of defoamer can also eliminate this situation. Adding appropriate amount of defoamer can also eliminate this situation.

Since hydroxypropyl methyl cellulose is used in a variety of industries, it is important to master the dissolution method of hydroxypropyl methyl cellulose for its correct use. In addition, users are reminded that in the process of use, we should pay attention to sunlight, rain and moisture, avoid direct light, sealed in a dry place for storage. Avoid contact with fire sources, and avoid the formation of large amounts of dust in a closed environment to prevent explosive hazards.