Synthesis and applications of polyacrylamide derivatives in the wet end of papermaking (Part II. Reactive N-chloropolyacrylamide)

Abstract

N-chloropolyacrylamide (N-Cl-PAM) obtained from the N-chlorination of the Hofmann reaction of polyacrylamide is easily transferred to the amino group, even with a reaction temperature as low as 0 °C. In this study we investigated how the N-chlorination of polyacrylamide with a low reaction temperature, under low alkaline conditions to avoid the N-chloroamide group forming the amino group (Hofmann reaction), obtained high conversions of the reactive N-chloroamide group. N-Cl-PAM is a highly reactive polymer that easily promotes paper strength. It reacts with the cellulose’s hydroxyl and carboxyl groups to form covalent bonds establishing a strong bond between agents and fibers. The established networks of the strengthening agents increase the quantity and quality of the hydrogen bond structures, and therefore the molecule bonding arrangement. It has better properties than anionic and cationic wet end additives for the improvement of paper strength.