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Ethyl cellulose is a derivative of cellulose in which some of the hydroxyl groups on the repeating glucose units are converted into ethyl ether groups. The number of ethyl groups can vary depending on the manufacturer.
E 2977 (OTTO) Ethyl cellulose, 48.0-49.5% (w/w) ethoxyl basis Cas 9004-57-3 - used as a thin-film coaterial.