| 摘要 |
PURPOSE:To inhibit effectively undesirable polymerization from occurring after the polymerization reaction, by adding a specified deactivator to the polymerization reaction mixture in the high-temperature high-pressure polymerization of ethylene with the aid of a Ziegler catalyst. CONSTITUTION:In polymerizing ethylene or a mixture of ethylene with a 3C or higher alpha-olefin at a temperature >=125 deg.C and a pressure >=200kg/cm<2> in the presence of a catalyst obtained from a transition metal derivative and an organoaluminum compound; a deactivator comprising silica having hydroxyl groups on its surface (e.g., tetraethoxysilane) and an alkoxyaluminum (e.g., isopropoxyalminum) is added to the polymerization reaction mixture, whereby the catalyst is deactivated and undesirable polymerization of ethylene after the polymerization reaction step is inhibited. The deactivator used does not inhibit the polymerization reaction of ethylene because it is not incorporated into ethylene which is recirculated from the separator to the polymerization reactor.
|
