Process for producing ethylene-based polymers with low hexane extractables

US10494460B2 · kind B2 · utility

Assignee

• DOW GLOBAL TECHNOLOGIES LLC · US

Inventors

• Otto J. Berbee · Hulst, NL
• Cornelis F. J. Den Doelder · Terneuzen, NL
• Stefan Hinrichs · Wondelgem, BE
• Teresa P. Karjala · Lake Jackson, US
• John O. Osby · Lake Jackson, US

Key dates

• Filing date: Jun 23, 2016
• Grant date: Dec 3, 2019
• Expiry date: Sep 10, 2036

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/582
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Ethylene-based polymers comprising the following properties: (A) a density from 0.9190 g/cc to 0.9240 g/cc; (B) a hexane extractable level that is less than or equal to the lower of: (1) (A+(B*density (g/cc))+(C*log(MI) dg/min)) based on total weight of the ethylene-based polymer; where A=250.5 wt %, B=−270 wt %/(g/cc), C=0.25 wt %/[log(dg/min)], or (2) 2.0 wt %; (C) a G′ (at G″=500 Pa, 170° C.) that meets the following equation: G′≥D+E[log (12)], where D=150 Pa and E=−60 Pa/[log(dg/min)]; and (D) a melt index (12) from 1.0 to 20 dg/min; are made in process comprising the step of contacting in a reaction configuration, comprising a first tubular reaction zone 1 and a last tubular reaction zone i, in which i is greater than or equal to (≥) 3, under high pressure polymerization conditions, and in which the first reaction zone 1 has a peak polymerization temperature greater than the peak temperature of the ith reaction zone, and wherein the difference in these two peak temperatures is ≥30° C.