Effect of polymerization parameters including cocatalyst concentration, polymerization time, temperature and free solvent (bulk) technique on the behavior of a dinuclear α–diimine Ni-based catalyst ((1E,1’E,2E,2’E)-N1,N1’-(2,3,5,6-tetramethyl-1,4- phenylene)bis(N2-(2,6-diisopropylphenyl)acenaphthylene-1,2-diimine) dinickel tetra bromide) was investigated. As there was an optimum [Al]/[Ni] molar ratio, it also observed that higher concentration of diethyl aluminum chloride (DEAC) could decrease the normal insertion through the chain walking. Although, polymerization temperature showed an optimum point (25 °C), monomer conversion increased by time. Branching density (BD) for bulk polymerization was higher indicating normal insertion which led to greater butyl branches on microstructure. Distribution of branches along with BD disclosed that they could reduce the glass transition temperature (Tg) due to increasing chain mobility. Complete chain walking was a reason to reach lower BD, and subsequently, to create methylene sequence and melting area.

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