Patent · US Expired

Process to produce bimodal polyolefins with metallocene catalysts using two reaction zones

US6380311B1 · kind B1 · utility

19Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 7, 2000
Grant dateApr 30, 2002
Priority date
Expiry dateFeb 7, 2020

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08L2314/06
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process for the preparation of polyolefins having a bi- or multimodal molecular weight distribution, the process comprising the steps of: (i) contacting an olefin monomer and a first co-reactant with a catalyst system in a first reaction zone under first polymerization conditions to produce a product comprising a first polyolefin having a first molecular weight distribution; and (ii) contacting an olefin monomer and a second co-reactant with a catalyst system in a second reaction zone under second polymerization conditions to produce a product comprising a second polyolefin having a second molecular weight distribution different from the first molecular weight distribution; wherein the first and second polyolefins are mixed together, wherein one of the co-reactants is hydrogen and the other is a comonomer selected from butene, methylpentene, hexene or octene, and wherein each catalyst system comprises (a) a metallocene catalyst component comprising a bis tetrahydroindenly compound of the general formula (IndH4)2R″MQ2 in which each Ind is the same or different and is indenyl or substituted indenyl, R″ is a bridge which comprises a C1-C4 alkylene radical, a dialkly mern…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.