Chemical modification of cotton with chloroacetamide

Abstract Chemically modified cellulosic textile materials have been prepared by treatment of cotton with chloroacetamide in the presence of strong alkali by a variety of techniques. Ether groups bearing carboxyl and amide functions were attached to the cellulose. The effects of process variables on the chemical and physical properties of the products are discussed. These variables include time and temperature of reaction, concentration of reactants, choice of solvent, and method of application. Nucleophilic reaction of cellulose with chloroacetamide introduces carbamoylmethyl ether groups along the polymer chain. In the alkaline reaction media employed the hydrolysis of these substituents proceeds with loss of ammonia, yielding carboxymethyl ether groups. The amount and ratio of the carboxymethyl and carbamoylmethyl substituents introduced can be altered by varying the reaction conditions. In general, low temperature and a high ratio of chloroacetamide to alkali in the reaction medium favor carbamoylmethylation, whereas at higher temperatures the overall reaction kinetics favor amide hydrolysis, and carboxymethylation predominates. Chloroacetamide is an excellent carboxymethylating agent for cellulose; in some instances greater carboxymethyl substitution was achieved with this agent than with chloroacetic acid. Degrees of substitution can be attained that render the cotton soluble in dilute aqueous alkali. However, the original fibrous nature of the cotton was retained even in products with relatively high degrees of substitution.