Multistage process for the polymerization of ethylene
US8557931B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 2010 |
| Grant date | Oct 15, 2013 |
| Priority date | — |
| Expiry date | Apr 3, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F210/16
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention relates to a slurry process for preparing an ethylene polymer having a melt flow ratio F/P, according to ASTM 1238, of higher than 25, carried out in two or more stages of polymerization at temperatures in the range from 60 to 120° C., in which at least two of the said two or more polymerization stages are carried out under different concentration of a molecular weight regulator, said process being carried out in the presence of a catalyst system comprising the product obtained by contacting (A) a solid catalyst component comprising Ti, Mg, halogen, and having a porosity (PF), measured by the mercury method and due to pores with radius equal to, or lower than, 1 μm of at least 0.3 cm3/g and a surface area determined by BET method, of lower than 100 m2/g, and (B) of an organoaluminum compound.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.