Concerted Steric and Electronic Strategy in Thermostable Salicylaldiminato Nickel Catalysts for Ethylene (Co)polymerization

Olefin polymerization is one of the most important chemical reactions in industry. This work presents a strategy that emphasizes the synergistic meta/para-steric hindrance of N-aryl groups and electronic effects in newly synthesized neutral salicylaldiminato nickel catalysts. These nickel(II) catalysts exhibit exceptional thermostability, ranging from 30 °C to 130 °C, demonstrating enhanced catalytic activities and broad ly regulated polyethylene molecular weights (3−341 kg·mol−1) and controlled polymer branch density (2−102 brs/1000C). The preferred catalyst Ni3 with concerted steric and electronic effects enables the production of solid-state semi-crystalline polyethylene materials at temperatures be low 90 °C. Notably, Ni3 exhibits an impressive tolerance of 110 °C and can withstand even the challenging polymerization temperature of 130 °C, leading to the production of polyethylene wax and oil. Also, functionalized polyethylene is produced.