Basic properties of building material grade cellulose ether

Additives play a key role in improving the performance of building dry-mix mortar, accounting for more than 40% of the material cost in dry-mix mortar. A considerable part of the admixtures in the domestic market are supplied by foreign manufacturers, and the reference dosage of the products is also provided by the suppliers. As a result, the cost of dry-mix mortar products remains high, and it is difficult to promote ordinary masonry and plastering mortars with large quantities and wide coverage. High-end market products are controlled by foreign companies, and dry-mix mortar manufacturers have low profits and poor price tolerance; the application of admixtures lacks systematic and targeted research, and blindly follows foreign formulas.
Water retaining agent is a key admixture to improve the water retention performance of dry-mix mortar, and it is also one of the key admixtures that determine the cost of dry-mix mortar materials. The main function of cellulose ether is to retain water.
Cellulose ether is a general term for a series of products generated by the reaction of alkali cellulose and etherifying agent under certain conditions. Alkali cellulose is replaced by different etherifying agents to obtain different cellulose ethers. According to the ionization properties of the substituents, cellulose ethers can be divided into two categories: ionic (such as carboxymethyl cellulose) and non-ionic (such as methyl cellulose). According to the type of substituent, cellulose ether can be divided into monoether (such as methyl cellulose) and mixed ether (such as hydroxypropyl methyl cellulose). According to different solubility, it can be divided into water-soluble (such as hydroxyethyl cellulose) and organic solvent-soluble (such as ethyl cellulose). Dry-mixed mortar mainly uses water-soluble cellulose, which is further divided into quick-soluble type and delayed-soluble type after surface treatment.