| abstract |
A process for the production of polyolefins which comprises polymerizing or copolymerizing olefins in the presence of a catalyst composition which at least comprises:n a catalyst component (I) resulting from mutual contact of sub-components (A) and (B),n said sub-component (A) being of the formula n n R 1 p Me 1 X 1 4-p and/or R 1 2 Me 1 X 1' n nwherein Me 1 is a transition metal of the IVa Group in the Periodic Table, R 1 is either of cyclopentadienyl, substituted cyclopentadienyl, indenyl, substituted indenyl, fluorenyl and substituted fluorenyl groups which may be bonded through a C 2 -C 18 hydrocarbon group and/or a silylene group, X 1 is a halogen atom, a hydrogen atom or a C 1 -C 24 hydrocarbon group, p is an interger of 1≤p≤4, and X 1' is a C 1 -C 20 alkylidene group, and said sub-component (B) being a modified organoaluminum compound having Al-a-Al bonds; and a catalyst component (II) selected from the group of sub-components (C) and (E),n said sub-component (C) being a transition metal elemental compound belonging to the IV-VIII Groups in the Periodic Table and selected specifically from the group consisting of oxides, halides, carbonates, acetates, alkoxides, acetylacetonates, metallocenes, hydrogen complexes, alkyl complexes, phosphine complexes, cyano complexes, pyridyl complexes and carbonyl complexes of said transition metal elemental compound, or a compound resulting from mutual contact of said transition metal elemental compound and a compound (D) of the formula n n Me'R' m (OR") n X' z-m-n n nwherein R' and R" each are a C 1 -C 24 hydrocarbon group, X' is a halogen or hydrogen atom, Me' is an element of the I-III Groups in the Periodic Table, z is a valence of Me', m and n are 0<m≤z and 0≤n≤z, respectively and 0<m+n≤z; and said sub-component (E) being a transition metal of the IV-VIII Groups in the Periodic Table. nEither of the catalyst components (I) and (II) is contacted, during or after the preparation thereof, with an inorganic compound carrier and/or a particulate polymer carrier. The disclosed catalysts find application particularly in the production of polyolefins having enhanced molecular weights and a relatively wide molecular weight distribution and olefin copolymers having a relatively narrow composition distribution at increased rate of yield. |