PROCESS FOR PREPARING POLYOLEFINS

摘要

Olefins are polymerized in the presence of a catalyst which comprises the combination of: ¢I! a solid substance obtained by the reaction of: (i) a magnesium halide, (ii) at least one compound represented by the general formula Me(OR) X wherein Me is a Group I-VIII n z-n element in the Periodic Table, with the limitation that silicon, titanium and vanadium are excluded, R is a hydrocarbon radical having 1 to 24 carbon atoms, X is a halogen atom, z is the valence of Me and n is O < n < ?, and (iii) a titanium compound and/or a vanadium compound; ¢II! a silicon compound represented by the general formula R'msi(OR")nX4-m-n wherein R' and R" are each a hydrocarbon radical having 1 to 24 carbon atoms, X is a halogen atom, m is O < m <4 And n is O < n < 4, provided O < m + n < 4. ¢III! an organometallic compound.