Patent ID: 6538070
Filing Date: 2003-03-25
Classification: C08F,C08L

Abstract:
An interpolymer product made by a process comprising the steps of:(a) polymerizing a first homogeneous ethylene/alpha-olefin interpolymer using a first activated constrained geometry catalyst composition having a first reactivity such that the first interpolymer has from about 5 to about 30 weight percent alpha-olefin comonomer content, a melt index of from about 0.05 to about 50 grams/10 minutes measured according to ASTM D-1238 at 190 C./2.16 kg, a melting point less than about 110Â° C., wherein the first activated constrained geometry catalyst composition comprises (i) a metal coordination complex corresponding to the formula: â€ƒwherein: M is a metal of group 4 of the Periodic Table of the Elements; Cp* is a cyclopentadienyl or substituted cyclopentadienyl group bound in an &eegr;5 bonding mode to M; Z is a moiety comprising boron, or a member of group 14 of the Periodic Table of the Elements, and optionally sulphur or oxygen, said moiety having up to 20 non-hydrogen atoms, and optionally Cp* and Z together form a fused ring system; X independently each occurrence is an anionic ligand group having up to 30 non-hydrogen atoms; n is 0, 1, or 2 and is 2 less than the valence of M; and Y is an anionic ligand group bonded to Z and M comprising nitrogen, phosphorous, oxygen or sulphur and having up to 20 non-hydrogen atoms, optionally Y and Z together form a fused ring system; and (ii) an activating cocatalyst; (b) polymerizing at least one second homogeneous ethylene/alpha-olefin interpolymer using a second activated constrained geometry catalyst composition having a second reactivity such that the second ethylene/alpha-olefin interpolymer has from about 2 to about 10 weight percent alpha-olefin comonomer content, a melt index of from about 0.05 to about 50 grams/10 minutes measured according to ASTM D-1238 at 190 C./2.16 kg, a melting point greater than about 115Â° C., wherein the second activated constrained geometry catalyst composition comprises (i) a metal coordination complex corresponding to the formula: â€ƒwherein: M is a metal of group 4 of the Periodic Table of the Elements; Cp* is a cyclopentadienyl or substituted cyclopentadienyl group bound in an &eegr;5 bonding mode to M; Z is a moiety comprising boron, or a member of group 14 of the Periodic Table of the Elements, and optionally sulphur or oxygen, said moiety having up to 20 non-hydrogen atoms, and optionally Cp* and Z together form a fused ring system; X independently each occurrence is an anionic ligand group having up to 30 non-hydrogen atoms; n is 0, 1, or 2 and is 2 less than the valence of M; and Y is an anionic ligand group bonded to Z and M comprising nitrogen, phosphorous, oxygen or sulphur and having up to 20 non-hydrogen atoms, optionally Y and Z together form a fused ring system; and (ii) an activating cocatalyst; wherein the second reactivity differs from the first reactivity; and (c) combining from about 50 to about 95 weight percent of the first homogeneous ethylene/alpha-olefin interpolymer with from about 5 to about 50 weight percent of the second homogeneous ethylene/alpha-olefin interpolymer to form the ethylene/alpha-olefin interpolymer product, wherein the first homogeneous ethylene/alpha-olefin interpolymer and the second homogeneous ethylene/alpha-olefin interpolymer are combined in amounts effective to yield an interpolymer product having a Mw/Mn of from about 2 to about 6 and a crystallization onset temperature at least about 5Â° C. higher than the crystallization onset temperature of the interpolymer produced by the activated constrained geometry catalyst composition having the higher reactivity.