ИСТИНА

The metallocene is represented by a formula I, wherein M = Group 3, 4, 5 or 6 transition metal, a lanthanide metal, or actinide metal, preferably a Group 4 transition metal selected from titanium, zirconium or hafnium; E = substituted or unsubstituted monocyclic or polycyclic arenyl ligand pi-​bonded to M; A = substituted or unsubstituted polycyclic arenyl ligand that is pi-​bonded to M and has a different ring structure with the E ligand; ≥1 of the A and E ligands includes ≥1 halogen substituent directly bonded to an sp2 carbon at a bondable ring position; Y = bridging group contg. ≥1 Group 13, 14, 15, or 16 element and any single position of the ring structure of A and to any single position of the ring structure of E; and y = 0 or 1; and each X = a univalent anionic ligand, or two X are joined and bound to the metal atom to form a metallocycle ring, or two X are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand. Thus, 3.05 g 2-​methyl-​7-​bromoindene was reacted with Bu lithium, added with 4.86 g pentamethylcyclopentadienyl zirconium trichloride heated at 100° for 20 h to give 5.17 g (η5-​2-​methyl-​4-​bromoindenyl)​(η5-​pentamethylcyclopentadienyl)​zirconium dichloride after the workup, which was combined with MAO to polymerize ethylene to give polyethylene with activity 21.686 g​/(mmol·h·atm)​.