Hot water dissolution method: Since HPMC does not dissolve in hot water, HPMC can be evenly dispersed in hot water at the beginning, and then quickly dissolve when cooled. Two typical methods are described as follows:
1) Put the required amount of hot water in the container and heat it to about 70℃. Add hydroxypropyl methylcellulose gradually under slow stirring. HPMC will float on the surface of the water at first, and then gradually form a slurry. Cool the slurry under stirring.
2) Add 1/3 or 2/3 of the required amount of water to the container and heat it to 70℃. Disperse HPMC according to method 1) to prepare hot water slurry; then add the remaining amount of cold water to the hot water slurry, stir and cool the mixture. Powder mixing method: Mix HPMC powder with a large amount of other powdered ingredients with a mixer, then add water to dissolve. At this time, HPMC can be dissolved without agglomeration, because there is only a little HPMC powder in each tiny corner, which will dissolve immediately when it encounters water. --Putty powder and mortar manufacturers use this method. [Hydroxypropyl methylcellulose (HPMC) is used as a thickener and water-retaining agent in putty mortar.
