Catalyst component and catalyst for the production of very high molecular weight polyolefins
US5070051A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1991 |
| Grant date | Dec 3, 1991 |
| Priority date | — |
| Expiry date | Feb 22, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F10/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A solid catalyst component for the low-pressure polymerization of ethylene and C.sub.3 -C.sub.10 alpha-olefins into very high molecular weight polyolefins is in the form of a spherical granular solid having a surface area of between 20 and 40 m.sup.2 /g, a mean pore radius of between 5,000 and 40,000 .ANG. and a porosity of between 40 and 90 vol %, and is definable by the following formula (in atomic proportions: EQU X (1), Mg (1-8), Al (0.2-0.8), Cl (5-20), (Et+OEt+OR) (1-3); where: X=Hf or Zr; Et=ethyl group; OEt=ethoxy group; and OR=alkoxy group containing from 2 to 8 carbon atoms in the linear or branched alkyl portion. Such a catalyst component is obtained by preparing a solid spherical granular support by spray-drying an ethanolic solution of magnesium chloride, reacting said support with a hafnium or zirconium alkoxide or halogenalkoxide, and finally reacting the thus treated support with an alkyl aluminum chloride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.