Nickel Catalyst With Excellent Thermal Stability for Ethylene Polymerization and Copolymerization

Recently, a series of inexpensive nickel-based phosphine phenol catalysts have been synthesized for catalyzing the copolymerization of ethylene and polar monomers to prepare functionalized polyolefins. However, it is still challenging to achieve homogeneous nickel catalysts that catalyze ethylene polymerization or copolymerization at high temperatures (up to 150°C) with high activity. This work synthesized a series of phosphine phenol nickel catalysts with bulky steric hindrance and electron donating groups, which were used for catalyzing ethylene polymerization and coordination copolymerization of ethylene and a series of polar monomers at high temperatures. These nickel catalysts exhibited high ethylene polymerization activity and excellent thermal stability at 150°C, producing polyethylene with a molecular weight of up to 102.7 × 10⁴ g mol⁻¹. More importantly, these catalysts can catalyze the copolymerization of ethylene and a range of polar monomers at 120°C, improving the surface properties of polyolefins.