Cellulose ethers glucose derivatives

Most of the selective-etherification studies on polysaccharides have been made with cellulose, and nearly all of them have involved quantitative separation of the D-glucose derivatives formed on hydrolysis of the partially substituted celluloses. In view of their stability, ethers of polysaccharides are particularly suited to this approach. 

Ethers and water-soluble derivatives of cellulose have been assayed spectro-photometrically following reaction of D-glucose or substituted o-glucose derivatives released on hydrolysis with 4-hydroxybenzoylhydrazine. Hydrolysis of the polysaccharides was achieved more readily with trifluoroacetic acid than with sulphuric acid. 

Total hydrolysis of the polymers gave D-glucose only. Water-soluble derivatives (ethyl or carboxymethyl ethers) of the polymers were unaffected by a-amylase, but were partially hydrolyzed by a ceUulase preparation from Acdobader xylinum. The optical rotations of several preparations of this polyglucose and of cellulose (P 1150) in tetraethylammonium hydroxide were all 0°, thereby strongly suggesting that the polyglucoses are /S-D-linked.109... 

Lignin is an important component of wood, which functions primarily as an interfiber bonding agent. It is a three-dimensional, cross-linked polymer of heterogeneous structure composed of predominantly n-propylbenzene units joined by a variety of ether (C-O-C) and carbon-carbon (C-C) links (Fig. 15.3). Lignin is also biosynthetically derived from glucose, like cellulose. 

The separation of those methyl ethers of n-glucose likely to be encountered in research on cellulose derivatives has also been studied. ... 

A number of derivatives of cellulose are used commercially. Most of these are compounds in which two or three of the free hydroxyl groups of each glucose unit have been converted to an ester or an ether. This conversion substantially alters the physical properties of the material, making it more soluble in organic solvents and allowing it to be made into fibers and films. Treating cellulose with acetic anhydride produces the triacetate known as Arnel or acetate, used widely in the textile industry. Cellulose trinitrate, also called gun cotton or nitrocellulose, is used in explosives. 

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