Reactions of fullerene C₆₀ with methyl methacrylate radicals: A density functional theory study

Abstract

We have investigated the stepwise addition of four growing methyl methacrylate (MMA) radicals to C60 fullerene, taking into account all possible types of the formed adducts. This reaction set is a reliable approximation for understanding the MMA polymerization process in the presence of C60 fullerene. We have analyzed the structures of the fullerene‐MMA adducts and energy parameters of their formation (heat effects and activation enthalpies). We found that up to three MMA growing radicals are favorably attached to C60 as the fullerene‐MMA trisadduct is a stable radical of the allyl type. It is inactive for further radical addition, and the elimination of the hydrogen atom from the growing MMA radical becomes preferable. The effects of steric factors and structures of the products of multiple growing MMA radical additions to C60 on the radical polymerization of MMA in the presence of C60 fullerene are considered.

Thermal decomposition of polymethylmethacrylate and its composite with fullerene C-=SUB=-60-=/SUB=- after ultraviolet irradiation

“…Since at the selected irradiation dose the neat PMMA spectrum features in the stage C range are less intense than those of the composite, the composite spectrum in this temperature range may be assumed to be caused by the UV−induced formation of the C 60 covalent bonds with macromolecular side groups. The possibility of formation of these bonds is consistent with the quantum chemistry calculations [16]. The increase in the stage C intensity in the composite spectra prior to irradiation may evidence for that a similar binding mechanism takes place also upon heating.…”

Computational insights into the Multi-Diels-Alder reactions of neutral C60 and its Li+ encapsulated analogue: A DFT study

“…Since its discovery, buckminsterfullerene [1 ] has been considered as an important precursor for several chemical compounds which have wide-scale applications [2][3][4][5][6][7] , ranging from material science to biological sciences [8][9][10] . The functionalization of the fullerene cages including polymeric derivatives has sorted out some of the problems associated with low solubility and miscibility of corresponding C 60 systems [11 ] .In the past decades, a large number of fullerene derivatives have been synthesized and characterized with desirable applications [12][13][14][15] , such as photoelectric conversion [16 ] , magnetic resonance imaging [17 ] , cancer therapy [18 ] and so on. Among the experimental and theoretical methods implemented for fullerene modifications, Diels-Alder cycloaddition reaction [19][20][21][22][23] on the fullerene surface and encapsulation of atom/metal cluster/small molecules into the hollow cage of fullerene [24][25][26][27] are drawing great scientific attention.…”

Reactivity of short radicals at the initial stages of radical polymerization of allyl chloride: Chain growth versus addition to fullerene

“…The calculations were performed with the PBE/3z [12] method implemented in the Priroda 09 program [13]. According to previous works [14][15][16][17], this method accurately describes both the energy and structural parameters of the C 60 fullerene and its derivatives.…”

“…[atoms 16 and 29], respectively) relative to the position of the first radical addition (the numeration is according to IUPAC recommendations [19] [Figure 2]). Previous experimental and computational works [14,15,[21][22][23][24][25][26] revealed that the second radical mainly reacts with monoadduct C 60 R • via positions 4 or 4 0 and 16 or 16 0 of the fullerene core. We have previously shown that the model polystyrene and polymethylmethacrylate radicals are attached via positions 4 and 4 0 [14,15].…”

“…Previous experimental and computational works [14,15,[21][22][23][24][25][26] revealed that the second radical mainly reacts with monoadduct C 60 R • via positions 4 or 4 0 and 16 or 16 0 of the fullerene core. We have previously shown that the model polystyrene and polymethylmethacrylate radicals are attached via positions 4 and 4 0 [14,15]. Thus, in the present work, we consider these positions (atoms labeled 4 and 11 according to IUPAC) as the only reaction sites of the bisadduct С 60 R 2 formation due to the AC radical attachment.…”