发明名称 |
HERSTELLUNG VON POLYETHYLEN MIT BIMODALER MOLEKULARGEWICHTSVERTEILUNG |
摘要 |
A process for producing high density polyethylene having a large molecular weight distribution, in particular a bimodal molecular weight distribution. The process comprises polymerisation ethylene or copolymerising ethylene and an alpha-olefinic comonomer comprising from 3 to 10 carbon atoms in the presence of a catalyst system comprising a chromium-based catalyst and an alkyl metal oxane. The alkyl metal oxane may comprise methyl aluminium oxide in an amount of around 2ppm based on the weight of the chromium-based catalyst. The chromium-based catalyst may comprise an activated chromium oxide on a support comprising silica and titania, the catalyst comprising around 1wt% chromium. The polymerisation or copolymerisation is preferably performed at a temperature of around 85 DEG C at a pressure of around 24 bar. There is further provided a catalyst system for polymerising ethylene or copolymerising ethylene and an alpha-olefinic comonomer to produce high density polyethylene, the catalyst system comprising in combination the chromium-based catalyst and the alkyl metal oxane. There is further provided the use of the catalyst system for increasing the bimodality of the molecular weight distribution of a high density polyethylene. |
申请公布号 |
AT200297(T) |
申请公布日期 |
2001.04.15 |
申请号 |
AT19970953880T |
申请日期 |
1997.12.19 |
申请人 |
FINA RESEARCH S.A. |
发明人 |
DEBRAS, GUY;BODART, PHILIPPE |
分类号 |
C08F4/69;C08F10/02;C08F210/16 |
主分类号 |
C08F4/69 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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