What factors affect the water retention of hydroxypropyl methyl cellulose?

Hpmc Powder Uses can be uniformly and effectively dispersed in cement mortar and gypsum based products, wrapping all solid particles and forming a wetting film. The moisture in the base is gradually released over a considerable period of time, and undergoes hydration reaction with inorganic cementitious materials, thereby ensuring the bonding strength and compressive strength of the materials.

Therefore, in high temperature summer construction, in order to achieve water retention effect, it is necessary to add sufficient amounts ofhydroxypropyl methyl celluloseaccording to the formula, otherwise quality problems such as insufficient hydration, reduced strength, cracking, hollowing, and detachment caused by rapid drying will occur, and it will also increase the difficulty of workers in construction. As the temperature decreases, the amount of hydroxypropylmethylcellulose can be gradually reduced, and the same water retention effect can be achieved.

The water retention of hydroxypropyl methyl cellulose is influenced by temperature and the following factors:

1. Homogeneity of hydroxypropyl methyl cellulose

Homogeneoushydroxypropyl methyl cellulose, Methoxy group and hydroxypropyl are evenly distributed, and the water retention rate is high.

2. Temperature of HPMC thermal gel

The thermal gel has high temperature and high water retention rate; On the contrary, the water retention rate is low.

3. Hydroxypropylmethylcelluloseviscosity

When the viscosity ofHPMCincreases, the water retention rate also increases; When the viscosity reaches a certain level, the increase in water retention tends to be gradual.

4. Addition amount of hydroxypropyl methyl cellulose

The larger the amount of hydroxypropyl methyl cellulose added, the higher the water retention rate and the better the water retention effect. In the range of 0.25-0.6% addition, the water retention rate increases rapidly with the increase of addition amount; As the addition amount further increases, the increasing trend of water retention rate slows down