Eco-friendly synthesis of regenerable antimicrobial polymeric resin with N-halamine and quaternary ammonium salt groups

An effective macroporous cross-linked antimicrobial polymeric resin containing N-halamine and quaternary ammonium salt moieties was synthesized in an eco-friendly and economical way. Commercially available macroporous crosslinked chloromethylated polystyrene (CMPS) resin reacted with the salt of 5,5-dimethylhydantoin (DMH) and trimethylamine (TMA) in water to produce a polymeric resin containing hydantoinyl and quaternary ammonium salt moieties, poly(p-methylstyrene)-3-(5,5-dimethylhydantoin)-co-trimethyl ammonium chloride (PSHTMA). The hydantoinyl groups in PSHTMA were converted to an antimicrobial N-halamine structure by a facile chlorination reaction in dilute NaOCl solution. The as-synthesized antimicrobial polymeric resin (Cl-PSHTMA) was characterized by FT-IR, X-ray photoelectron spectroscopy, and zeta-potential measurement. The antimicrobial tests showed that the as-synthesized antimicrobial polymeric resin was capable of 7-log inactivation of S. aureus and 8-log inactivation of E. coli within 1 minute contact time. Moreover, the N-halamine moieties in Cl-PSHTMA exhibited excellent regenerability.