| 摘要 |
<p>A process for producing polyethylene having improved crack resistance, the process comprising copolymerising ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms, in the presence of a chromium-based catalyst in a first reactor, feeding the polyethylene copolymer thereby produced and the chromium-based catalyst to a second reactor, and in the second reactor copolymerising ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms, in the presence of the chromium-based catalyst thereby to produce a second polyethylene product, the first and second polyethylene products forming a combined polyethylene having a monomodal molecular weight distribution.</p> |
