Heterogenization of an Anilinonaphthoquinone‐Chelated Nickel Complex for Ethylene Polymerization Using Silica‐Supported Modified Methylaluminoxane

An anilinonaphthoquinone‐ligated nickel complex [Ni(C 10 H 5 O 2 NC 6 H 3– 2,6‐iPr 2 )(Ph)(PPh 3 )] ( 1 ) activated with silica‐supported modified methylaluminoxane is found to be effective for ethylene polymerization under atmospheric pressure at low Al/Ni ratio. The activity of this system becomes maximal at 60 °C with a steady polymerization rate. The molecular weight of the produced polymer monotonously decreases with raising polymerization temperature, but the high‐molecularweight polymer with the number‐average molecular weight of 119 000 g mol−1 is obtained even at 80 °C. The produced polymer possesses methyl branches, the content of which is increased by raising the polymerization temperature. Consequently, the melting point of the produced polymer decreases from 130 to 120 °C by raising the polymerization temperature from 40 to 80 °C.