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Carboxymethyl cellulose (CMC) or cellulose gum is a cellulose derivative with carboxymethyl groups (-CH2-COOH) bound to some of the hydroxyl groups of the glucopyranose monomers that make up the cellulose backbone.
S 5774 (OTTO) Sodium carboxymethyl cellulose average Mw ~90,000 Cas 9004-32-4 - used as its sodium salt, sodium carboxymethyl cellulose.