title: Self-assembly directed synthesis of poly(ortho-toluidine)-metal(gold and palladium) composite nanospheres.
abstract: Poly(ortho-toluidine) (POT)-gold (Au) and palladium (Pd) composite nanospheres were successfully synthesized by the reaction of o-toluidine with the corresponding metal (Au or Pd) colloidal solution through self-assembly process in the presence of dodecylbenzenesulfonic acid (DBSA), which acts as both a dopant and surfactant, and ammonium peroxydisulfate as an oxidizing agent. The composites (POT-DBSA/Au or Pd) were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, UV-Visible (UV-Vis) spectroscopy, and electrical conductivity measurements. TEM images of the nanocomposites reveal that metal (Au or Pd) nanoparticles were well dispersed on POT spheres. TGA and XRD results show that the composites exhibit high thermal stability and are more crystalline compared with pristine POT. It was found that the electrical conductivity of the POT-DBSA/Au or Pd composites is 2 orders of magnitude higher than that of pristine polymer. Also, the POT-DBSA/Pd composite exhibits magnetic property. The formation mechanism of the POT-DBSA/Au or Pd composite nanosphere is discussed.
authors.affiliation: Department of Chemistry Graduate School, Kyungpook National University, Daegu 702-701, South Korea.
authors.forename: Kakarla Raghava
authors.initials: KR
authors.lastname: Reddy
authors.forename: Kwang-Pill
authors.initials: KP
authors.lastname: Lee
authors.forename: Anantha Iyenger
authors.initials: AI
authors.lastname: Gopalan
mesh_terms: D003911:Dextrans / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D054118:Nanospheres / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010100:Oxygen / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013449:Sulfonamides / Q000737:chemistry; D013818:Thermogravimetry / Q000379:methods; D014052:Toluidines / Q000138:chemical synthesis / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D003911:Dextrans; D011108:Polymers; D013449:Sulfonamides; D014052:Toluidines; C076040:dextran-bound sulfonamide; D010165:Palladium; D006046:Gold; C023622:2-toluidine; D010100:Oxygen