Patent ID: 6291609
Filing Date: 2001-09-18
Classification: C08F,C08L,Y10S

Abstract:
A polymerization process for ethylene copolymers having a density of about 0.87 to about 0.93 comprising contacting, under homogeneous polymerization conditions at a reaction temperature at or above 140.degree. C. to 220.degree. C., ethylene and one or more comonomers capable of insertion polymerization with a hafnocene catalyst complex derived from:(A) a biscyclopentadienyl hafnium organometallic compound having:(i) one unsubstituted cyclopentadienyl ligand and one aromatic fused-ring substituted cyclopentadienyl ligand, or two aromatic fused-ring substituted cyclopentadienyl ligands; and(ii) a covalent bridge connecting the two cyclopentadienyl ligands, said bridge comprising a single carbon or silicon atom; and(B) an activating cocatalyst precursor ionic compound comprising a halogenated tetraaryl-substituted Group 13 anion wherein each aryl substituent contains at least two cyclic aromatic rings.