Catalytic system for the (co)polymerization of alpha-olefins
AssigneeEnichem S.p.A.
InventorsRoberto Fusco, Luca Longo, Antonio Proto, Diego Vigliarolo, Gianfranco Guglielmetti, Liliana Gila
Life of this patent
Estimating the term…
Abstract
A catalytic system with an increased activity for the (co)polymerization of alpha-olefins comprises a catalyst of the metallocene type, which is capable of polymerizing olefins without aluminoxane, and a weak coordinating compound, which, when used in a polymerization process, enables a higher productivity than an analogous process carried out with the metallocene type catalyst per se.
Claims22
A process for the (co)polymerization of alpha-olefins, in the absence of organo-oxygenated compounds of metals of groups 13 or 14 of the Periodic Table of Elements, comprising feeding said alpha-olefin and optional co-monomers to a continuous or batch reactor, and (co)polymerizing the mixture in suspension or solution in a suitable liquid medium in the presence of a polymerization process wherein said process comprises the following components in contact with each other:
- (A) an ionic metallocene compound of a metal selected from the group consisting of titanium, zirconium and hafnium, wherein said compound has a cation and an anion, and wherein said metal is included in the cation, and wherein said compound has the property itself of promoting the polymerization of olefins without organo-oxygenated compounds of metals of groups 13 or 14 of the periodic table of elements,
- (B) a substance not containing metal atoms, and containing at least one heteroatom selected from the group consisting of O, N, P and S, characterized in that this substance (B) consists of an aprotic polar compound having a dielectric constant greater than or equal to 3 and co-ordinating capacity DN less than or equal to 10 kcal/mole.
Dependencies are inferred from the claim text.