Hydroxyethyl Cellulose (HEC)
Appearance: white or yellowish flowable liquid, odorless and smellless; Sieving efficiency(40 mesh):99% min. ; Softening temperature: 135-140°C; Apparent density: 0.35-0.61g/ml; Decomposition temperature: 205-210°C; slow combustion speed, balanced moisture content: 23°C, 50rh%: 6%£84rg%: 29%; Soluble in cold water and heat water, usually insoluble in most organic solvents. The viscosity become little when the PH ranges from 2 to 12, but the viscosity reduces beyond this range. The HEC treated on the surface is soluble only when the pH is from 8 to 10.
As a nonionic surfactant, HEC has the functions such as thickening, suspension, emulsification, adhesion, film formation, dispersion, water retention, providing protection and the following properties:
1. Hydroxyethyl Cellulose (HEC) is soluble in heat water or cold water, don't precipitate under high temperature or boiling, solubility and viscosity changes in a wide range;
2. Because of its nonionic property, it can coexist with other water-soluble polymer, surfactants and salts in wide range, is an excellent colloid thickener for high-concentration electrolyte solution;
3. Its water retention is twice of methyl cellulose, with excellent flow controllability;
4. Its dispersibility is the worst compared with methyl cellulose and hydroxypropyl cellulose, but the protection power for colloid is the strongest.
1. Used in Water Emulsion Coating:
HEC is used to protect colloid in acetic alkene emulsion polymerization, improve the stability of polymer in wide pH range, make pigment and additives uniformly disperse, stable and thicken in production of finished products. It is also used as dispersant in suspensive polymer such as styrene, acrylate, acrylonitrile, etc.
2. Used in Drilling Well:
As thickener used in all kinds of mud in drilling well, well cementation and fracturing operation, HEC can make mud excellent fluidity and stability, improve the carrying power of mud in drilling well and prevent water from going into oil layer from mud, make the output of oil layer stable.
3. Used in Building Materials:
Because of its strong water retention, Hydroxyethyl cellulose is an excellent thickener and adhesive for cement paste and mortar to improve fluidity and operation performance, lengthen vaporizing time of water, improve the beginning strength and avoid crack. It can effectively improve the water retention and adhesive strength when used in gypsum plastering, gypsum cementing and gypsum putty.
4. Used in Toothpaste:
Because of its strong salt resistance and acid resistance, Hydroxyethyl Cellulose (HEC) can make toothpaste stable; Because of its strong water retention and emulsification power, it make tooth not easy to dry;
5. Used in Water-soluble Ink, HEC can make ink dry fast and not penetrate.
Moreover, HEC is widely used in textile, printing, paper making, daily chemical, etc.
Dissolving and Preparing Method
1. Add clean water in vessel;
2. Add HEC under low-speed agitation, agitate to make all materials fully wet;
3. After HEC fully dissolve, add other needed ingredients;
4. Add alkali or ammonia to adjust pH to 8-10, form needed viscosity.
Mole Degree of Substitution (M.S) 1.8-2.0
Moisture: 10% max.
Water-insoluble Matter: 0.5% max
Ash: 5% max
Viscosity(mpa.s), 20°C aqueous solution: 5-60000
HEC's model is expressed as HS-6000, 6000 stands for nominal viscosity. If treated on the surface. its model is expressed as HS-6000S.