A STUDY ON THE THERMAL STABILITY OF THE PHOTOPOLYMER, THE OZOPOLYMER, AND THE PHOTOCHLORINATED DERIVATIVE OF C₆₀FULLERENE

Abstract

The thermal stability of the C 60 photopolymer, the C 60 ozopolymer, and photochlorinated C 60 was studied by thermogravimetric analysis (TGA) ultraviolet-visible (UV-vis) and TGAdifferential thermal analysis techniques up to 950 • C in comparison to graphite and pure C 60 . The ozopolymer was found to be the least stable material followed by C 60 Cl x . The resulting residual carbonaceous matter formed by the decomposition of the photopolymer and the ozopolymer has been studied by Fourier transform-infrared (F TIR) spectroscopy and has been found to be completely comparable to carbon black. The thermal decomposition of the C 60 photopolymer prepared in solution yields negligible amounts of C 60 . The main product is carbon black. 55

Structural Analogies and Differences Between Graphite Oxide and C60 and C70 Polymeric Oxides (Fullerene Ozopolymers)

“…[6] Of course X-ray pattern of C 60 -PFO does not correspond anymore to the pattern of the pristine C 60 [23] which in fact it is characterized by the most intense reflection at 2y ¼ 10.834 followed by other two intense peaks at 2y ¼ 17.698 and 20.776 . Other low intensity reflections of C 60 appear at 2y ¼ 21.711 , 27.432 , 28.190 , 30.882 , 32.823.…”

“…Both curves reach a incipient plateau at about 600-650 C. However, at that temperature, the weight loss of C 60 -PFO is roughly À60% vs. À40% of C 70 -PFO underlining the reduced content of adsorbed moisture in the case of C 70 -PFO and also a reduced degree of oxygenated groups in comparison to the other PFO. As discussed in a previous work, [6] the differential thermal analysis (DTA) of PFO is characterized by a strong endothermal peak at about 113 C due to the evaporation of the bound water and by a broad exothermal decomposition with a peak located at 300-350 C but with onset temperature for the decomposition at much lower temperature (around 200-220 C). Figure 1 also shows the thermal behavior of graphite oxide prepared in the present work and studied with the same thermobalance and under the same conditions as for the PFO samples.…”

“…In fact, upon exposure to air for months its original weight was doubled. [5] The TGA of PFO under an inert atmosphere [6,7] is characterized by a 10% weight loss at about 100 C due to elimination of trapped solvent and absorbed water. Exactly the same weight loss is reported in Ref.…”

“…[4,5] The polymeric nature and the chemical structure of the resulting product has already been studied. [4][5][6][7][8][9] We have named the polymeric materials obtained by prolonged ozonation of C 60 and C 70 ''fullerene ozopolymers'' [4][5][6][7][8][9] and also ''polymeric fullerene oxides'' PFO and they will be referred in this way in the subsequent part of this paper.…”