Scalable Nickel Catalysts\nfor Carbonylative Terpolymerization\nof Ethylene/α-Olefin with High Efficiency

The carbonylative polymerization of olefin yields aliphatic\npolyketones,\nwhich are used as engineering plastics in the market due to their\nexcellent mechanical strength, chemical resistance, and surface and\nbarrier properties. However, the usage of precious palladium catalysts\nhas restricted their extensive application as commodity materials.\nHerein, we present a series of phosphine-sulfonate Ni catalysts with\na wide spectrum of electronic and steric substituents on the phosphorus\nmoiety for the carbonylative polymerization of ethylene. Such efficient\nnickel-catalyzed copolymerization shows the on-demand transformation\nof ethylene/CO gas to polyketones with quantitative yield and product\nspecificity. A remarkable productivity of up to 20 kg PK (g Ni)<sup>−1</sup> was obtained during ethylene/propylene/CO terpolymerization,\nand the polymerization productivity is independent of the type and\nfeeding amount of α-olefin. The resulting terpolymers show comparable\ncrystallinity, thermal stability, and tensile properties with commercial\nPOKETONE products from Hyosung. The nickel catalyst also features\nthe advantages of using cheap raw material sources and simple synthetic\nprocedures that can be scaled up easily, which enables it to be a\npromising candidate for industrial application.