Hot water dissolution method: Since hpmc does not dissolve in hot water, hpmc can be uniformly dispersed in hot water at the initial stage, and then quickly dissolve during cooling. Two typical methods are described as follows:
1) Put the required amount of hot water in the container and heat it to about 70°C. Gradually add hydroxypropyl methylcellulose with slow stirring, start hpmc floating on the surface of water, and then gradually form a slurry, and cool the slurry with stirring.
2) Add 1/3 or 2/3 of the required amount of water into the container and heat it to 70°C. According to the method of 1), disperse hpmc to prepare hot water slurry; then add the remaining amount of cold water to hot water In the slurry, cool the mixture after stirring.
Powder mixing method: Mix the hpmc powder with a large number of other powdery materials, mix them thoroughly with a mixer, and then add water to dissolve, then the hpmc can be dissolved without clumping, because each tiny corner has only a little hpmc The powder will dissolve immediately when it meets water. —— Putty powder and mortar manufacturers use this method. [Hydroxypropyl methylcellulose (hpmc) is used as a thickener and water-retaining agent in putty powder mortar. ]