To continue our previous researches on dinuclear late transition metal catalysts, a dinuclear catalyst based on cobalt (C) was prepared and used for polymerization of ethylene in the presence of modified methylaluminoxane (MMAO) as cocatalyst. The behavior of catalyst C was compared with its mononuclear analogue (M). The initial results showed higher in both activity and stability of the catalyst C in comparison to catalyst M. Based on this, the studies were focused on the catalyst C. The maximum activity of C observed at [Al]/[Co] molar ratio of 2000:1, reaction temperature of 60 °C that was equal to 6.8 × 106 g PE/mol Co.h. The GPC-IR results showed that the synthesized polyethylene has low Mw (Mw = 7.0 × 103 g/mol) along with a narrow MWD (2.56). Moreover, the polyethylene was containing low SCB (7.8 CH /1000C) in confirmation of high crystallinity obtained by DSC (χc3 = 60%). Due to layered morphology of the catalyst C observed through SEM images, the shape of PE was layered consistent on replication phenomenon. Besides, this morphology observed in SEM and TEM images of PE/xGnP composites with higher intensity. The presence of xGnP also led to a slightly greater activity of the catalyst C along with higher vinyl content and lower starting degradation temperature of the obtained PE.

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