Synthesis, characterization and ethylene polymerization behavior of binuclear iron complexes bearing N,N′-bis(1-(6-(1-(arylimino)ethyl) pyridin-2-yl)ethylidene)benzidines

Abstract

A series of N,N′-bis(1-(6-(1-(arylimino)ethyl)pyridin-2-yl)ethylidene)benzidines and the bi-metallic iron complexes thereof have been synthesized and fully characterized. All iron complexes, when activated by MAO or MMAO, exhibited high activities of up to 1.3 × 10⁷ g mol⁻¹ (Fe) h⁻¹ for the polymerization of ethylene. On comparison with their mononuclear counterparts, such bi-metallic complexes not only retain a relatively high activity at elevated temperatures (up to 70 °C), but also exhibit increased lifetimes. The polyethylenes obtained were characterized by GPC, DSC and high temperature NMR spectroscopy, which indicated multimodal and highly linear features.