| 摘要 |
A supported Ziegler catalyst prepared by the following steps: (A) heating together at a temperature in the range 250 to 1100.degree.C a refractory oxide support material having surface hydroxyl groups and one or more halogen-free metal derivatives which are hydrides and/or organic derlvatives of the metal. (B) reacting the product from (A) with one or more organometallic compounds having the feneral formula MRIaQb-a wherein M is a metal atom, R1 is a hydrocarbon group, Q is a halogen or an oxyhdrocarbyl group, b is the valency of M and a is an integer from 1 to b and wherein the metal atom M is aluminium, boron, lithium, zinc or magnesium, (C) impregnating the solid protuct from step (B) with one or more halogen-containing transition metal compounds wherein the transition metal or metals comprise titsnium and/or vanadium and/or zirconium. |
