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The initiation of radical polymerization of methyl methacrylate in the presence of benzoyl perox ide-metallocene (Cp 2 Fe, Cp 2 ZrCl 2 , and Cp 2 TiCl 2 ; (C 5 Me 5 ) 2 Fe, (C 5 Me 5 ) 2 ZrCl 2 , and (AcC 5 H 4 )(C 5 H 5 )Fe) systems is studied. It is shown that a metallocene affects the rate of initiation and the initial rate of polymer ization. On the basis of quantum chemical calculations, a new mechanism of the initiation reaction may be advanced: Namely, the decomposition of benzoyl peroxide proceeds via the stage of complexation with a metallocene, while the nature of a metallocene determines the probability of complexation and decomposi tion.

Modeling of the addition of various radicals to C 60 fullerene is currently an active research area. However, the radicals considered are not able to adequately model polymeric radicals. In this work, we have performed a theoretical study of the possible reactions of C 60 fullerene with 1-n-phenylpropyl radicals, which are used to model polystyrene radicals. Several possible ways of subsequent addition of up to four 1-phenylpropyl radicals to C 60 have been analyzed, the structures of the intermediates have been defined and thermal properties, such as the activation enthalpies of the corresponding reactions, have been calculated using density functional theory with the approximation of PBE/3z. It is shown that the topology of the spin density distribution on the fullerenyl radical causes regioselectivity for further radical addition. According to the energetic characteristics of the reactions, we assume the possibility of formation of products of one-, two-, three-, and four-addition of the growth radical to the fullerene core in radical polymerization of styrene in the presence of C 60 fullerene.

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.

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