Ionic Cluster Catalyst Assembly Strategy for Ethylene Polymerization and Copolymerization

The performance regulation of polyolefin catalysts typically relies on complex ligand design and synthesis, which limits the rapid development of high-performance polyolefins. The heterogenization of homogeneous catalysts presents a promising and industrially favorable approach to modulate and enhance the performance of transition-metal catalysts. This work introduces a general ionic cluster catalyst assembly (ICCA) strategy to achieve efficient in situ heterogenization without the need for any catalyst supports. It transforms known hydroxyl-functionalized transition-metal catalysts into ionic cluster assemblies by a simple one-step reaction. The steric hindrance of the catalyst metal center can be easily tuned by varying the feed ratios for assembly, without requiring the synthesis of new catalysts. This ICCA strategy enables up to 20 times higher activity during ethylene homo- and copolymerization while significantly improving the molecular weight and mechanical properties of the resulting copolymers. Furthermore, the in situ heterogeneous polymerization facilitated by this strategy demonstrates efficient heat transfer, lower system viscosity, and excellent fouling resistance during polymerization, indicating great potentials for scale-up polymerization. This work provides a general and efficient platform for tuning polyolefin catalyst performance.