Synthesis and characterization of [60]fullerene-poly(3-azidomethyl-3-methyl oxetane) and its thermal decomposition

Abstract

A new functionalized fullerene derivative, [60]fullerene-poly(3-azidomethyl-3-methyl oxetane) (C₆₀-PAMMO), was synthesized for the first time using a modified Bingel reaction with [60]fullerene (C₆₀) and bromomalonic acid poly(3-azidomethyl-3-methyl oxetane) ester (BM-PAMMO). The product was characterized by Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis), and nuclear magnetic resonance (NMR) spectroscopy analyses. The results confirmed the successful preparation of C₆₀-PAMMO. Moreover, the thermal decomposition of C₆₀-PAMMO was analyzed by differential scanning calorimetry (DSC), thermogravimetric analysis coupled with infrared spectroscopy (TG-IR), and in situ FTIR spectroscopy. The decomposition of C₆₀-PAMMO showed a three-step thermal process. The first step at approximately 150 °C was related to the cycloaddition of the azido groups (–N₃) with [60]fullerene. The second step was ascribed to the decomposition of the remaining PAMMO main chain at approximately 320 °C. The final step was attributed to the burning decomposition of amorphous carbon, the main chain, N-heterocyclic components and the carbon cage around 510 °C.