title: Simple efficient synthesis of strongly luminescent polypyrene with intrinsic conductivity and high carbon yield by chemical oxidative polymerization of pyrene.
abstract: A wholly aromatic polypyrene was synthesized by direct chemical oxidative polymerization of pyrene with ferric chloride as oxidant in hexane/nitromethane. Successful synthesis of polypyrene was thoroughly confirmed by IR, UV/Vis, 1D (1)H NMR, 2D (1)H-(1)H COSY, 2D (1)H-(13)C HSQC, MALDI-TOF MS, elemental analysis, and X-ray diffraction methods. The results indicated that the polypyrene was formed mainly through dehydro coupling between 2- or 1- and 2'- or 1'-positions on pyrene rings having a degree of polymerization of around 24. The polypyrene was purified and then separated into THF-soluble (ca. 10 %) and THF-insoluble (ca. 90 %) fractions. Compared with insulating pyrene monomer, the polypyrene is a controllably conducting polymer that has low conductivity of 3.4x10(-8) S cm(-1) in its virgin state, moderate conductivity of 2.28x10(-4) S cm(-1) upon iodine doping, but much higher conductivity of up to 81.2 S cm(-1) after the insoluble polypyrene was heated up to 1300 degrees C in nitrogen with a high char yield of 70.6 %. In particular, the soluble polypyrene demonstrates much stronger visible color fluorescence and much lower toxicity than pyrene. The soluble polypyrene would be advantageous for detecting Fe(3+) with almost no interference of other metal ions. The soluble and insoluble polypyrene fractions have potential applications as intrinsically luminescent and highly conducting carbon materials, respectively.
authors.affiliation: Institute of Materials Chemistry, College of Materials Science and Engineering, Tongji University, 1239 Si-Ping Road, Shanghai 200092, China. adamxgli@yahoo.com
authors.forename: Xin-Gui
authors.initials: XG
authors.lastname: Li
authors.forename: You-Wei
authors.initials: YW
authors.lastname: Liu
authors.forename: Mei-Rong
authors.initials: MR
authors.lastname: Huang
authors.forename: Sai
authors.initials: S
authors.lastname: Peng
authors.forename: Ling-Zhi
authors.initials: LZ
authors.lastname: Gong
authors.forename: Mark G
authors.initials: MG
authors.lastname: Moloney