Action of Acids on Cellulose Ethers

Action of acids on cellulose ethers. Cellulose ethers, like cellulose, are hydrolyzable by acids. Methods for viscosity reduction of the ethers have been proposed which involve treatment of the ether with sulfuric acid31 or with gaseous hydrogen chloride.32... 

Cellulose ethers generally are very stable. Many etherified cottons are highly resistant to hydrolytic removal of substituent groups under both acidic and alkaline conditions. Because of this stability, many of the most practical chemical treatments of cotton are based on etherification reactions [9,328-331]. These treatments provide cotton products with useful, durable properties including wrinkle resistance, water repellency, flame resistance, and antimicrobial action. 

Collodions are liquid preparations composed of pyroxylin (soluble gun cotton, collodion cotton) dissolved in a solvent mixture composed of alcohol (94% ethanol) and ether with or without added medicinals. Pyroxylin is obtained by the action of nitric and sulfuric acids on cotton or other ceUulosic material to produce cellulose tetranitrate. Pyroxylin is completely soluble in 25 parts of a mixture of 3 volumes of ether and 1 volume of alcohol. It is extremely flammable and must be stored in a well-closed container away from flame, heat, and light. Collodions are intended for external use as a protective coating to the skin. When medicated, it leaves a thin layer of that medication firmly placed against the skin. 

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