Abstract:

A New kind of modified montmoriUonite was prepared by introducing Zn²⁺ and quaternary ammonium cations into montmorillonite via the ion exchange,which was used as an antibacterial agent.The optimal preparation conditions were also investigated,and the mass fractions of Zn and tetradecyldimethyl benzyl ammonium were 2.95% and 12.18% ,respectively.The results of XRD and TG reveal a perfect exchange of Zn²⁺ and quaternary ammonium cations into montmorillonite as well as an onset decomposition temperature of the quaternary ammonium cation of about 210℃.Th e investigation into the antibacterial property of the prepared composite antibacterial agent shows that the minimal inhibitory concentrations(MIC)towards E.coli,S.aureus and P. aeruginosa are no more than 300 mg/L,which shows that the antibacterial agent possesses excellent antibacterial property and rather wide antibacterial spectrum.Moreover,the composite antibacterial agent exhibits good resistance to water-its antibacte.rial property remains excellent even after a dipping in deionized water at 50℃ for 30 h.

Key words: composite an tibacterial agent, quaternary ammonium cation, zinc ion, modified montmorillonite, preparation, antibacterial property