Two binuclear late transition metal -LTM- catalysts -A=2,4,6-trimetyl-C6H2-N=C--C10H6- -C=N-C6-CH3-4-N=C--C10H6--C=N-2,4,6-trimetyl-C6H2}-NiBr2-2 and B=2,4,6-trimetyl-C6H2-N=C--C2H6--C=N-C6-CH3-4-N=C--C2H6--C=N-2,4,6-trimetyl-C6H2}-NiBr2-2- were used in 1-hexene homopolymerization. The experiments carried out using A/EASC and B/EASC catalytic systems at the optimum conditions of each catalyst.The productivity of each catalyst, viscosity average molecular weight -Mv- and polydispersity index -PDI- of obtained poly-1-hexene- were compared. The activity of A was higher than B due to presence of acenaphthene group on C-C bond through the increasing of steric hindrance, decreasing of N-Ni-N bond angel leading to block axial sites by methyl groups and high cooperative effect of metal centers in the A. Moreover, the Mv of resulted poly-1-hexene-in presence of catalyst -A- was 2.32×105 g.mol-1 and PDI=2.11 which were higher and broader than B catalyst -Mv=1.56×105 g.mol-1, PDI=1.94-. These results can be attributed to steric and electronic effects of backbone which can control the rate of propagation to chain transfer reactions.

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