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The influence of bis[4,6-di- tert-butyl- N-(2,6-dimethylphenyl)- o-iminobenzosemiquinonato]cobalt( ii) and 4,6-di- tert-butyl- N-(2,6-diisopropylphenyl)- o-iminobenzosemiquinonato]-[4,6-di- tert-butyl- N-(2,6-diisopropylphenyl)- o-amidophenolate]manganese( iii) on polymerization of methyl methacrylate and acrylonitrile in the presence of azobisisobutyronitrile (as a traditional radical initiator) and alkyl halides (used for initiation of controlled atom transfer radical polymerization process) was studied. The effect of the nature of the activating agents (amines) and the temperature conditions on the overall polymerization rate of the indicated monomers, as well as molecular weight characteristics of the synthesized polymers, were analyzed. The optimal conditions for the synthesis of polyacrylonitrile and poly(methyl methacrylate) with a relatively narrow molecular weight distribution were selected. [ABSTRACT FROM AUTHOR]

Polymerization of methyl methacrylate and styrene in the presence of manganese cyclopentadienylcarbonyl complexes containing π-alkene (methyl methacrylate), vinylidene, and allenylidene ligands was investigated. It was found that metal complex ligand environment plays a key role in the initiation of the polymerization and in the regulation of the molecular weight characteristics of synthesized polymers. In particular, the manganese complexes with cumulenylidene ligands are capable to initiate spontaneously polymerization of vinyl monomers. The process of polymerization proceeds to high conversions (over 90%), and the resulting polymers are characterized by high values of molecular weight and relatively broad molecular weight distribution. [ABSTRACT FROM AUTHOR]