Cellulose ether is a major additive in the dry-mix mortar. Although the addition amount is very low, it can significantly improve the performance of mortar. It can improve the consistency, working performance, bonding properties and water retention properties of mortar, and plays a very important role in the field of dry-mix mortar. Its main features are as follows:
- Excellent Water Retention
Water retention is one of the important indicators to measure the quality of the cellulose ether and becomes even more important especially in the thin layer construction. Improving the water retention of mortar can effectively prevent the drying cased by too fast water loss, and the phenomena of strength decrease and cracking resulting from insufficient cement hydration. The factors affecting the water retention of mortar include the dosage, viscosity, fineness and use environment of cellulose ether. In general, the higher the viscosity is; the finer the fineness is; and the greater the dosage is, the better the water retention will be. The water retention of cellulose ether is related to the degree of etherification. When the content of methoxy group is the highest, the water retention is the best.
- Strong Adhesive Force and Good Sag Resistance
Cellulose ether has a very good thickening effect. Adding cellulose ether into dry-mix mortar can make the viscosity increase by several thousand times, the mortar have better adhesion and pasted tiles have better sag resistance. The viscosity degree of cellulose ether can affect the bond strength, fluidity, structural stability and constructability of mortar.
Generally speaking, the higher the viscosity is, the better the water retention effects will be. But the higher the viscosity is, the higher the molecular weight of cellulose ether will be. Its dissolution performance will be reduced accordingly, which has a negative effect on the strength and construction performance of mortar. The higher the viscosity is, the stickier the wet mortar will be. It is easy to stick the scraper, of little help to increase the structural strength of wet mortar itself, and not obvious in improving anti-sagging effects.
- Good Solubility
Since the surface particle of cellulose ether is specially processed, it is very good in the solubility whether in cement mortar, plaster or coatings system, not easy to agglomerate, and fast in the dissolution speed.