Radiation-cured polyisoprene/C60 fullerene nanocomposite. Part 1: Synthesis in hexane and in toluene

Fullerene C60 can be grafted onto polyisoprene chains by γ irradiation in n-hexane or in toluene. The resulting polyisoprene/C60 nanocomposites can be easily recovered from the solutions and have been characterized by electronic absorption and Fourier transform-infrared (FT-IR) spectroscopy. The electronic absorption spectroscopy clearly shows that C60 undergoes addition reaction from the polyisoprene macroradicals formed by γ radiolysis. FT-IR spectroscopy supports the grafting reaction of polyisoprene on C60 and additionally it shows that C60 acts as a sensitizer for the partial cis–trans isomerization of the polyisoprene monomeric units. Relatively high levels of C60 lead the polyisoprene-based nanocomposite to a crosslinked gel.The thermal behaviour of the polyisoprene/C60 nanocomposites has been studied by the thermogravimetric analysis (TGA-DTG). It is shown that the radical adducts polyisoprene/C60 are thermally reversible and regenerate free C60 during the pyrolysis under N2.