ИСТИНА

A catalyst system for the preparation of ethylene copolymers in a high temperature solution process comprising (I) a metallocene complex of formula (I) wherein M is Hf or Zr, X is a sigma ligand and L is of formula-SiR8 2A bridge of (a) wherein each R8Independently is C1‑C20-hydrocarbyl, tri (C)1‑C20Alkyl) silyl, C6‑C20-aryl, C7‑C20-aralkyl radical or C7‑C20-alkylaryl, n is 0,1 or 2, R1And R1′Identical or capable of being different and can be linear or branched C1‑C6-alkyl radical, R2And R2′Are the same or different and are CH2‑R9Group, wherein R9Is H or straight or branched C1‑C6-alkyl radical, R5And R5′Identical or different and can be H or straight-chain or branched C1‑C6-an alkyl group OR an OR group, wherein R is C1‑C6-alkyl radical, R6And R6′Identical or different and can be H or C (R)10)3Group, wherein R10Are the same or different and R10Can be H or straight or branched C1‑C6-an alkyl group, or R5And R6And/or R5′And R6′Together form an unsubstituted 4-7 membered ring fused to the phenyl ring of the indenyl moiety, provided that if R is5And R6And R5′And R6′Together form an unsubstituted 5-membered ring fused to the phenyl ring of the indenyl moiety, then R2And R2′Is other than C1-an alkyl group, and R7And R7′Can be identical or different and can be H or straight-chain or branched C1‑C6-an alkyl group; (ii) an aluminoxane cocatalyst; and (iii) optionally a boron-containing promoter.