Patent ID: 7262258

Claim:
A process for producing a copolymer of ethylene, an α-olefin having from 3 to 20 carbon atoms and optionally a polyene, which comprises the step of copolymerizing in a polymerization reactor ethylene, the α-olefin having from 3 to 20 carbon atoms and optionally the polyene by feeding to the polymerization reactor: (A) a transition metal complex, (B) an organic aluminum compound, (C1) a halogen-containing compound, and (D) a Lewis base, wherein the transition metal complex (A), the organic aluminum compound (B), the halogen-containing compound (C1) and the Lewis base (D) are fed to the polymerization reactor without a preliminary contact of (1) the transition metal complex (A) with the organic aluminum compound (B), (2) the transition metal complex (A) with the halogen-containing compound (C1), (3) the organic aluminum compound (B) with the halogen-containing compound (C1), and (4) the organic aluminum compound (B) with the Lewis base (D).