Synthesis of Branched Polyethylene Wax Using Bulky Iminopyridyl Nickel‐Catalyzed Ethylene Chain‐Walking Polymerization

ABSTRACT Pyridine‐imine nickel catalysts have consistently attracted significant attention due to their highly efficient catalytic performance and excellent chemical tunability in ethylene polymerization reactions. This study designed and synthesized three imine pyridine nickel complexes Ni1 – Ni3 . Ethylene polymerization was conducted in the presence of the coordinating catalyst Et 2 AlCl. Results indicate that increased steric hindrance near the active site significantly enhanced catalytic activity, reaching a maximum of 11.16 × 10 6 g mol −1 h −1 , while producing highly branched polyethylene waxes. To further enhance the performance of pyridine‐imine nickel catalysts, the copolymerization of ethylene with α‐olefins catalyzed by Ni1 was investigated. Compared to homogeneous polymerization, the copolymerization of ethylene with α‐olefins yielded polymers with higher branching density and molecular weight. This provides new insights into the structure–performance relationship of pyridine‐imine nickel catalysts and offers a promising strategy for synthesizing high‐performance polyethylene waxes.