The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 25, 2018
Filed:
Sep. 11, 2015
Borealis Ag, Vienna, AT;
Borealis AG, Vienna, AT;
Abstract
A process for the preparation of a copolymer of propylene and ethylene comprising polymerizing propylene and ethylene in the gas phase in the presence of a solid particulate catalyst free from an external carrier comprising: (i) a symmetrical complex of formula (I), wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from —R'C—, —R′C—CR′—, —R′Si—, —R′Si—SiR′—, —R′Ge—, wherein each R′ is independently a hydrogen atom, C-C-alkyl, tri(C-C-alkyl)silyl, C-C-aryl, C-C-arylalkyl or C-C-alkylaryl; Ris a C-Chydrocarbyl radical; m is 2 to 5; Ris a H or C-Chydrocarbyl radical; Ris a hydrogen atom or a Chydrocarbyl radical; n is 0 to 3; Ris a C-Chydrocarbyl radical and optionally two adjacent Rgroups taken together can form a further mono or multicyclic ring condensed to Ph ring optionally substituted by one or two groups R; and Ris a C-Calkyl radical; and (ii) a cocatalyst, preferably comprising an organometallic compound of a Group 13 metal; wherein the xylene soluble fraction of the propylene ethylene copolymer has an ethylene content of at least 10 wt % and an intrinsic viscosity of at least 1.2 dl/g.