Nanocomposites of Polyaniline with Silver Nanoparticles Prepared Using Water in Oil Microemulsions as Antibacterial Agents

摘要

Polyaniline (PAni) was synthesized by chemical oxidative polymerization of aniline monomer by ammonium peroxydisulfate using w/o microemulsion and from aqueous solution. Ag/PAni nanocomposites were then prepared using w/o microemulsion by the same polymerization method in pre-formed Ag nanoparticles prepared by the reduction of metal salts in microemulsion. PAni and Ag/PAni nanocomposites were characterized by UV-visible and Fourier transform infrared (FTIR) spectroscopy. Dynamic light scattering (DLS) results and scanning electron microscopic (SEM) SEM images showed that PAni synthesized in microemulsion was smaller in particle dimension than that obtained from the bulk. Thermogravimetric analysis (TGA) results showed that PAni from microemulsion has a lower thermal stability than PAni from bulk synthesis. Ag/PAni nanocomposites, however, showed somewhat better thermal stability compared to that of PANI from microemulsion. The antibacterial properties against Gram-negative, Escherichia coli and Gram-positive, Staphylococcus aureus were tested by zone of inhibition method and the results demonstrated that Ag/PAni nanocomposites have enhanced antibacterial efficiency compared to PAni generated in microemulsion which is more efficient than PAni prepared from aqueous solution.