Hydroxyethyl cellulose (HEC) is a white or light yellow, odorless, non-toxic fibrous or powdery solid, which is prepared by etherification reaction of alkaline cellulose and ethylene oxide (or chlorohydrin). Nonionic soluble cellulose ethers. In addition to thickening, suspending, binding, floating, film-forming, dispersing, water-retaining and providing protective colloid, it has the following properties:
1. HEC is soluble in hot water or cold water, high temperature or boiling without precipitation, so that it has a wide range of solubility and viscosity characteristics, and non-thermal gelation;
2. It is non-ionic and can coexist with a wide range of other water-soluble polymers, surfactants, and salts. It is an excellent colloidal thickener for 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 ability is the strongest. Due to its good properties of thickening, suspending, dispersing, emulsifying, adhering, film-forming, protecting moisture and providing protective colloid, HEC has been widely used in oil exploration, coatings, construction, medicine, 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 it in water as long as the following items are paid attention to. the
1. Before and after adding hydroxyethyl cellulose, it must be stirred continuously until the solution is completely transparent and clear. the
2. It must be slowly sieved into the mixing tank, do not directly add a large amount of hydroxyethyl cellulose or hydroxyethyl cellulose that has formed lumps and balls into the mixing tank. the
3. Water temperature and PH value in water have obvious relationship to the dissolution of hydroxyethyl cellulose, so special attention must be paid. the
4. Do not add some alkaline substances to the mixture before the hydroxyethyl cellulose powder is warmed through the water. Raising the PH value after warming will help dissolve. the
5. As far as possible, add anti-fungal agent as early as possible. the
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, nor will it form insoluble spherical colloids after adding water.