Formation and Thermal Stabilities Research of Ionic Liquids/α-ZrP Antibacterial Materials

Three different ionic liquids/alpha-zirconium phosphonates (IL-ZrP) composites antibacterial materials were prepared by introducing quarternary ammonium type ionic liquids (1-hexadecyl-3-methylimidazolium bromide, C(16)MIMBr; hexadecyl dimethyl benzyl ammonium chloride, C(16)HDBACCl; hexadecyl trimethyl ammonium chloride, C(16)CTACCl) into the interlayer of alpha-zirconium phosphonates (alpha-ZrP). The structure, components and thermal stability of composites was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscope (FTIR), Thermogravimetric-Fourier transform infrared spectroscope analysis (TG-FTIR). XRD patterns show that the interlayer spacing of IL-ZrP are larger than the original alpha-ZrP. It represents that the ionic liquids are intercalated into the layer of alpha-ZrP. TG-FTIR shows that the mass fraction of C(16)MIMBr, C(16)HDBACCl and C(16)CTACCl in three IL-ZrP are 53.11wt%, 50.65wt% and 51.25wt%, respectively. The onset temperatures of the decomposition for C(16)MIMBr, C(16)HDBACCl and C(16)CTACCl are 174 degrees C, 198 degrees C and 219 degrees C, while the onset temperatures of the decomposition for C(16)MIMBr-ZrP, C(16)HDBACCl-ZrP and C(16)CTACCl-ZrP are 219 degrees C, 225 degrees C and 263 degrees C. The existing of alpha-ZrP improves the thermal stability of ionic liquids. Among the three IL-ZrP, the C(16)MIMBr-ZrP has excellent antibacterial activity, (i.e. within 24 h, the minimal inhibitory concentration of C(16)MIMBr pillared alpha-zirconium phosphonates against S. aureus and E. coli is less than 19 mg/L).