Process for preparing a poly-1-olefin

US5798309A · kind A · utility

Assignee

• Hostalen Polyethylen GmbH · DE

Inventors

• Werner Breuers · Eppstein, DE
• Rainer Lecht · Kelkheim, DE
• Ludwig Bohm · Mainz, DE

Key dates

• Filing date: Dec 22, 1995
• Grant date: Aug 25, 1998
• Expiry date: Dec 22, 2015

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S526/904
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Process for preparing a poly-1-olefin By means of a highly active spherical Ziegler catalyst based on a dialkylmagnesium, spherical polymers can be obtained in the polymerization of alpha-olefins. A further advantage of the catalyst of the invention lies in the high catalyst activity, so that only very small amounts of the catalyst are required for the polymerization. The residual titanium and/or zirconium content in the polymers prepared according to the invention is less than 10 ppm. Owing to its good responsiveness to hydrogen, the catalyst is particularly suited to two-stage processes for preparing polymers having a broad bimodal molecular weight distribution. The replacement of sulfur-containing electron donors such as diethyl sulfite by alcohols such as ethanol leads to less odor problems and broadened opportunities for use of the polymer. Owing to the spherical shape of the particles and the associated very good flow behavior of the polymers and copolymers, considerable simplification and advantages in handling, drying and processing are achieved.