Advances in the initiation system and synthesis methods of cationic polyacrylamide: A review

Cationic polyacrylamide (CPAM) is a polyelectrolyte whose monomeric unit contains ionizable cationic groups. In recent years, CPAM has received increasing attention owing to its unique properties and superior performance compared with those of other conventional inorganic coagulants and organic polymeric flocculants. This review examined the recent advances in CPAM synthesis. The synthetic mechanisms include direct copolymerization and post-polymerization functionalization, and direct copolymerization mainly includes aqueous solution polymerization, micellar copolymerization, dispersion polymerization, inverse emulsion polymerization, and template polymerization. In addition, various choices for initiator preparation are summarized in this paper. In conclusion, we propose a future research prospect relating to CPAM synthesis and its application in water treatment.