| 摘要 |
A polymerization activator for polymerizing ethylene comprising a dialkylaluminum monofluoride mixed with minor amounts of at least one of dialkylaluminum hydride or halide and a trialkylaluminum. The activator preferably corresponds to the general formula (AlR2F)(AlR2H)b(AlR3)c or the general formula (AlR2F)(AlR2X)a wherein R is an alkyl group having 1 to 12 carbon atoms, 0.1</=b</=0.4, 0.05</=c</=0.2, X is a halogen other than fluorine, and 0.1</=a</=0.4. The activator is used in a catalytic system including at least one halide of a transition metal of Group IVB to VIB, the valency of the metal in the halide being not more than 3 and the atomic ratio of aluminum in the activator to transition metal in the catalyst lying between 0.1 and 10. The catalytic system is used in a high pressure and temperature process for polymerizing or copolymerizing ethylene. |
