Microscopical Properties of Some Cellulose Ethers

Abstract

Microscopical features of partially etherified cotton fibers are described through examination of benzyl, benzhydryl, and trityl celluloses. Reaction appeared to be uniform throughout the fibers. Refractive indices generally increased with increase in degree of substitution (DS). Both benzhydryl and trityl celluloses exhibited zero birefringence at intermediate levels of reaction. The birefringence of tritylated cotton increased at higher levels of substitution. Sub stituted cotton fibers are diflicult to beat apart in water; in common with the cellulose esters, the ethers yielded on beating less and less fibrillar material as DS was increased. Solubility of cross sections in 0.5 M Cupriethylenediamine hydroxide (Cuen) and in chloroform indicated slight differences in fibrillar architecture among the cellulose ethers, and marked differences between ethers and esters attributable to differences in methods of preparation.