Hydroxyethyl cellulose (HEC) is a white or light yellow, odorless, non-toxic fibrous or powdery solid prepared by etherification of alkaline cellulose and ethylene oxide (or chlorohydrin). Nonionic soluble cellulose ethers. In addition to thickening, suspending, binding, flotation, film-forming, dispersing, water-retaining and providing protective colloids, it has the following properties:
1. HEC is soluble in hot or cold water, and does not precipitate at high temperature or boiling, so that it has a wide range of solubility and viscosity characteristics, and non-thermal gelation;
2. The non-ionic itself can coexist with a wide range of other water-soluble polymers, surfactants and salts, and is an excellent colloidal thickener containing high-concentration electrolyte solutions;
3. The water retention capacity is twice as high as that of methyl cellulose, and it has better flow regulation.
4. Compared with the recognized methyl cellulose and hydroxypropyl methyl cellulose, the dispersing ability of HEC is the worst, but the protective colloid has the strongest ability. Because HEC has good properties of thickening, suspending, dispersing, emulsifying, bonding, film-forming, protecting moisture and providing protective colloid, it has been widely used in oil exploration, coatings, construction, medicine and food, textile, paper and polymer Polymerization and other fields.
Precautions:
Since the surface-treated hydroxyethyl cellulose is powder or cellulose solid, it is easy to handle and dissolve in water as long as the following matters are noted.
1. Before and after adding hydroxyethyl cellulose, it must be stirred continuously until the solution is completely transparent and clear.
2. It must be sieved into the mixing barrel slowly, and do not directly add the hydroxyethyl cellulose that has been formed into lumps and balls into the mixing barrel.
3. The water temperature and the pH value of the water have an obvious relationship with the dissolution of hydroxyethyl cellulose, so special attention should be paid to it.
4. Never add some alkaline substance to the mixture before the hydroxyethyl cellulose powder is warmed by the water. Raising the PH value after warming is helpful for dissolution.
5. As far as possible, add antifungal agents as early as possible.
6. When using high-viscosity hydroxyethyl cellulose, the concentration of the mother liquor should not be higher than 2.5-3%, otherwise the mother liquor will be difficult to handle. The post-treated hydroxyethyl cellulose is generally not easy to form lumps or spheres, and it will not form insoluble spherical colloids after adding water.
Post time: Nov-15-2022