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:
Jun. 18, 2024
Filed:
May. 30, 2019
Borealis Ag, Vienna, AT;
Anh Tuan Tran, Linz, AT;
Alexandra Romina Albunia, Linz, AT;
Joy Jie Cheng, Linz, AT;
Joseph Thorman, Porvoo, FI;
John Jamieson, Porvoo, FI;
Ravindra Tupe, Porvoo, FI;
BOREALIS AG, Vienna, AT;
Abstract
The invention provides a process for the preparation of a multimodal high density polyethylene (HDPE) having a melt flow rate (MFR) of 0.1 to 4.0 g/10 min, said process comprising: (i) polymerising ethylene in a first polymerisation stage in the presence of a Ziegler-Natta catalyst to prepare a first ethylene homopolymer having a MFRfrom 10 to 500 g/10 min; (ii) polymerising ethylene in a second polymerisation stage in the presence of said catalyst and said first ethylene homopolymer to prepare an ethylene homopolymer mixture comprising said first ethylene homopolymer and a second ethylene homopolymer, said mixture having a MFRfrom 50 to 1000 g/10 min; and (iii) polymerising ethylene and at least one alpha-olefin comonomer in a third polymerisation stage in the presence of said catalyst and said ethylene homopolymer mixture to prepare said multimodal HDPE.