1-Hexene homopolymer samples produced by a series of mononuclear -MCn, n = 1–3- and rigid/flexible bridged dinuclear -BCn, n = 1–7- Ni-based catalysts were characterized by 13C NMR, DSC, and GPC-IR analyses. Mononuclear catalysts through normal insertion produced poly-1-hexene- with a high amount of butyl branches, while dinuclear catalysts were able to polymerize 1-hexene with a high level of rare branches -ethyl and propyl- due to the partial chain walking mechanism. Theoretical calculation was employed in order to study the dinuclear catalysts, which confirmed the presence of two stereoisomers via the broadening of MWD, a different mechanism of polymerization and short chain branch -SCB- curves. The effects of the cocatalyst type -DEAC, EASC and MMAO- and concentration, time and temperature along with the polymerization of higher a-olefins -1-octene and 1-decene- on the behavior of dinuclear catalyst BC2 and polymer properties were investigated. As a result, in addition to catalyst structure, the monomer length and polymerization temperature were the two factors controlling the stability of the stereoisomers due to agostic interaction and kinetic energy, respectively.

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