Morphology and structure of a one-dimensional graphite polymer, poly-peri-naphthalene

Abstract

Very fine fibers of 3,4,9,10‐perylenetetracarboxylicdianhydride heated above 520 °C in argon (Ar) or argon/hydrogen (Ar/H2) gas were grown on pressed pellets. The fibers synthesized in Ar had a rectangular cross section of about 0.1–0.4 μm on a side with lengths up to 10 mm. By contrast, the fibers synthesized in Ar/H2 had a flat‐ribbon like morphology with dimensions of 0.1–0.2 μm on one side and 0.4–2.0 μm on the side. Transmission electron microscopy revealed that component molecules roughly stacked parallel to the fiber axis. Infrared spectra of the fibers synthesized at around 520–550 °C exhibited aromatic C–H and C■C absorptions. The IR and laser–Raman spectra of the fibers can reasonably be explained by theoretically estimated vibrational modes of a poly‐peri‐naphthalene (PPN) structure. From these results together with elemental analysis data, we conclude that the fibers essentially consist of PPN molecules.