Patent ID: 6777509
Filing Date: 2004-08-17
Classification: C08F

Abstract:
A process for preparing thermoplastic ethylene alpha olefin copolymer having a molecular weight distribution, Mw/Mn, of greater than 2.0, said process comprising polymerizing ethylene and at least one other C3 to 10 alpha olefin under medium pressure solution polymerization conditions at a temperature of greater than 170Â° C. and less than 300Â° C. in a single polymerization reactor in the presence of a catalyst system comprising:a phosphinimine catalyst defined by the formula: (Cp)aM(Pl)b(L)c wherein Pl is a phosphinimine ligand; Cp is selected from the group consisting of unsubstituted cyclopentadienyl, substituted cyclopentadienyl, unsubstituted indenyl, substituted indenyl, unsubstituted fluorenyl and substituted fluorenyl; L is selected from the group consisting of a hydrogen atom, a halogen atom, a C1-10 hydrocarbyl radical, a C1-10 alkoxy radical, a C5-10 aryl oxide radical; each of which said hydrocarbyl, alkoxy, and aryl oxide radicals may be unsubstituted by or further substituted by a halogen atom, a C1-18 alkyl radical, a C1-8 alkoxy radical, a C6-10 aryl or aryloxy radical, an amido radical which is unsubstituted or substituted by up to two C1-8 alkyl radicals; a phosphido radical which is unsubstituted or substituted by up to two C1-8 alkyl radicals; M is a metal selected from Ti, Hf and Zr; and wherein a is 1; b is 1; c is 1 or 2; and a+b+c=the valence of the metal M;2) a four coordinate boron activator; and 3) at least one trialkyl aluminum.