Polymerization of Fullerene in Solution with Free Electron Laser Irradiation

<jats:title>ABSTRACT</jats:title><jats:p>The free electron laser (FEL) of 450 or 500 nm was irradiated onto the pressed C<jats:sub>60</jats:sub>powder in vacuum. The grains with μm-order were observed showing the colors of blue, purple, yellow, and white in optical microscope images. The Ag(2) derived mode around 1460 cm<jats:sup>−1</jats:sup>in Raman spectra was observed from the grain, indicating the polymerization. The 100 μm-length grain was obtained just after dissolving the FEL irradiated specimens into the toluene and evaporating it. In order to expand the scale of C<jats:sub>60</jats:sub>polymer grains and to obtain an amorphous C<jats:sub>60</jats:sub>polymer, the FEL irradiation was carried out in solution to reduce the directivity for polymerization. Although polymerization was not promoted in C<jats:sub>60</jats:sub>precipitation in supersaturated solution due to low density of C<jats:sub>60</jats:sub>, the precipitation grown with the liquid-liquid interfacial precipitation (LLIP) method showed the 1454 cm<jats:sup>−1</jats:sup>Ag(2) derived mode in addition to the peaks around 1460 cm<jats:sup>−1</jats:sup>in toluene. In m-xylene with LLIP method, in a whole area of C<jats:sub>60</jats:sub>pillar-grains, polymerization was confirmed by the Raman analysis.</jats:p>