Hydroxypropyl methylcellulose, also known as HPMC, is a non-ionic cellulose ether made from refined cotton, a natural polymer material, through a series of chemical processes. It is a white or slightly yellowish powder, easily soluble in water, let me talk about the dissolution method of hydroxypropyl methylcellulose.
First of all, hydroxypropyl methylcellulose is mainly used as an additive for putty powder, mortar, and glue. It can be used as a water-retaining agent and retarder to increase pumpability when added to cement mortar; it can be used as an adhesive when added to putty powder and glue. To improve spreadability and prolong operable time, let's take Qingquan cellulose as an example to explain the dissolution method of hydroxypropyl methylcellulose.
Ordinary hydroxypropyl methylcellulose is stirred and dispersed with hot water first, then it can be dissolved after adding cold water to stir and cool;
Specific: Take 1/5-1/3 of the required amount of hot water, stir to make the added product fully swell, then add the remaining part of hot water, which can be cold water, or even ice water, and stir to a suitable temperature (10°C ) to dissolve completely.
Disperse hydroxypropyl methylcellulose in an organic solvent or wet it with an organic solvent, and then add it to cold water or add cold water to dissolve it well. The organic solvent can be ethanol, ethylene glycol, etc.
If agglomeration occurs when dissolving, it is because the stirring is insufficient or the ordinary model is directly added to cold water. At this time, it should be stirred quickly.
If bubbles are generated during dissolution, they can be left to stand for 2-12 hours (the specific time is determined by the consistency of the solution) or removed by vacuuming, pressurizing, etc., or an appropriate amount of defoaming agent can be added.
Hydroxypropyl methylcellulose is divided into slow-dissolving type and instant-dissolving type. The instant-dissolving type of hydroxypropyl methylcellulose can be directly dissolved in cold water.