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The solution structure of AlMe2F and its reactivity with a prototypical ansa-metallocene have been investigated by advanced NMR techniques, in an attempt to indirectly shed some light on the structure and working principles of methylalumoxane (MAO) mixtures in olefin polymerization. In solution, AlMe2F gives rise to a complex equilibrium of oligomeric species, including a heterocubane [(Me2Al)4F4] tetramer, resembling the behavior of MAO. This complex mixture reacts with (ETH)ZrMe2 (ETH= rac-[ethylenebis(4,5,6,7-tetrahydro-1-indenyl)]) to afford [(ETH)ZrMeδ+(μ-F)(AlMe2F)nAlMe3δ−] inner-sphere ion pairs through successive insertions/deinsertions of AlMe2F units into the Zr⋅⋅⋅(μ-F) bond. [ABSTRACT FROM AUTHOR]

The solution structure of AlMe 2 F and its reactivity with a prototypical ansa-metallocene have been investigated by advanced NMR techniques, in an attempt to indirectly shed some light on the structure and working principles of methylalumoxane (MAO) mixtures in olefin polymerization. In solution, AlMe 2 F gives rise to a complex equilibrium of oligomeric species, including a heterocubane [(Me 2 Al) 4 F 4 ] tetramer, resembling the behavior of MAO. This complex mixture reacts with (ETH)ZrMe 2 (ETH=rac-[ethylenebis(4,5,6,7-tetrahydro-1-indenyl)]) to afford [(ETH)ZrMe δ+ (μ-F)(AlMe 2 F) n AlMe 3 δ- ] inner-sphere ion pairs through successive insertions/deinsertions of AlMe 2 F units into the Zr⋅⋅⋅(μ-F) bond., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this review are reported some of the most relevant achievements in the chemistry of the ethylene⁻styrene copolymerization and in the characterization of the copolymer materials. Focus is put on the relationship between the structure of the catalyst and that of the obtained copolymer. On the other hand, the wide variety of copolymer architecture is related to the properties of the material and to the potential utility.