Studies on the Distribution of Substituents in Hydroxyethylcellulose

Abstract

Cellulose is a naturally-occurring linear polymer of β-d-glucopyranose residues (anhydroglucose units) joined through 1→4-glucosidic linkages. Each anhydroglucose unit (AGU) in every molecular chain (except those at chain ends) contains three hydroxyl groups, one primary and two secondary. Cellulose derivatives, usually ethers or esters, are obtained by substituting some of these hydroxyls with the desired substituent groups under appropriate conditions. Since most substitution reactions take place under heterogeneous conditions, the substitution pattern which develops is nonuniform.