| 摘要 |
A high-temperature, high-pressure process for polymerizing ethylene in a reactor system having at least two reaction zones with a catalytic system including an activator (a), a compound (b), and a compound (c). Compounds (b) and (c) are injected into different reaction zones. Activator (a) is selected from hydrides and organometallic compounds of a metal of groups I to III of the Periodic Table. Compound (b) is represented by the formula (TiCla) (MgCl2)y (AlCl3)z (RMgCl)b in which 2</=a</=3, y>/=2, O</=z </=1/3, O</=b</=1 and R is an aliphatic or aromatic hydrocarbon radical. Compound (c) is represented by the formula TiCl3 (AlCl3)w (E, TiCl4)x in which O</=w</=1/3, O</=x</=0, 03 and E is a diisoamyl- or di-n-butylether. The amounts of (a), (b), and (c) are such that the ratio Al/Ti is between 1 and 10 in each reaction zone. The resulting polymers have a wide molecular weight distribution and a substantial proportion of very high molecular weights and are suitable for the blow-extrusion technique. |
