Preparation of Polyvinylamine by the Hofmann Degradation of Polyacrylamide

Abstract

Abstract Polyvinylamine which contained 95.6 mol% amine units was obtained when the Hofmann degradation was applied to polyacrylamide by use of a very slight excess of sodium hypochlorite and a large excess of sodium hydroxide at 0 to −15 °C for about 15 h. Polyvinylamine hydrochloride (PVAm·HCl) was isolated almost quantitatively as a white powder. PVAm·HCl was freely soluble in water, but insoluble in organic solvents such as methanol, acetone, dioxane, N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO). The desalting of PVAm·HCl was performed by passing its aqueous solution through columns of ion exchange resins. The product containing 30.5% nitrogen was obtained in reasonable yield. Polyvinylamine was freely soluble in water, acetic acid, or lower alcohols, but insoluble in solvents such as acetone, dioxane, DMF, and DMSO.