Sodium Carboxyl Methyl Cellulose

Brief Overview
Sodium carboxy methyl cellulose is the sodium salt of carboxy methyl cellulose (CMC), and the carboxy methyl cellulose derivative (-CH2-COOH) is bonded to some of the hydroxy groups of the glucopyranose monomer constituting the cellulose backbone. It is synthesized from the base-catalyzed reaction of cellulose with chloroacetic acid. The polar (organic acid) carboxyl groups make the cellulose soluble and chemically reactive. The functional properties of CMC depend on the degree of substitution of the cellulose structure (i.e., how many hydroxyl groups participate in the substitution reaction), the chain length of the cellulose backbone structure, and the degree of clustering of the Carboxymethyl substituents.
Manufacturing Process
For sodium carboxymethyl cellulose (CMC), the manufacturing process is as follows: raw materials (refined cotton, caustic soda, alcohol) mixed, alkalify, etherification, washing neutralization, squeezing, washing, rake the dry, drying, crushing, and package. The main chemical reactions of sodium carboxymethyl cellulose are the alkalization reaction of cellulose with alkali to generate alkali cellulose and the etherification reaction of alkali cellulose with monochloro acetic acid.
Step 1: Alkalization: [C6H7O2(OH)3]n + nNaOH→ [C6H7O2(OH)2ONa]n + nH2O
Step 2: Etherification: [C6H7O2(OH)2ONa]n + nClCH2COONa → [C6H7O2(OH)2OCH2COONa]n + nNaCl