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 rapidly dissolved 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°C. The hydroxypropyl methylcellulose was gradually added with slow stirring, initially the hpmc floated to the surface of the water and then gradually formed a slurry which was cooled with stirring.
2) Add the required amount of 1/3 or 2/3 of the water in the container, and heat it to 70 ° C, according to the method of 1), disperse hpmc, prepare hot water slurry; then add the remaining amount of cold water to hot water In the slurry, the mixture was cooled after stirring.
Powder mixing method: mix the hpmc powder with a large amount of other powdery substances, mix thoroughly with a mixer, and then add water to dissolve, then the hpmc can be dissolved at this time without clumping together, because every tiny little corner has only a little hpmc The powder will dissolve immediately in contact with water. ——This method is used by putty powder and mortar manufacturers. [Hydroxypropyl methylcellulose (hpmc) is used as thickener and water retention agent in putty powder mortar. ]