Propylene polymers

US5773516A · kind A · utility

Assignee

• BASF SE

Inventors

• Stephan Huffer · Birkenfeld, DE
• Meinolf Kersting · Neustadt, DE
• Franz Langhauser · Bad Dürkheim, DE
• Rainer A. Werner · Annaberg-Buchholz, DE
• Stefan Seelert · Bischofswerda, DE
• Patrik Müller · Gothenburg, SE
• Jurgen Kerth · Eisenberg (Pfalz), DE

Key dates

• Filing date: Dec 6, 1996
• Grant date: Jun 30, 1998
• Expiry date: Dec 6, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F210/06
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Propylene polymers which comprise from 25 to 97% by weight of a propylene polymer (I) containing from 0 to 15% by weight of copolymerized C.sub.2 -C.sub.10 -alk-1-enes and also comprise from 3 to 75% by weight of a further propylene polymer (II) containing from 15 to 80% by weight of copolymerized C.sub.2 -C.sub.10 -alk-1-enes, are obtainable by two-stage polymerization of propylene and C.sub.2 -C.sub.10 -alk-1-enes in the presence of a Ziegler-Natta catalyst system which comprises a titanium-containing solid component a) comprising a compound of magnesium, a halogen, silica gel as support and a carboxylic ester as electron donor compound, and also as cocatalysts an aluminum compound b) and a further electron donor compound c), where, in a first polymerization stage, propylene is polymerized in the presence or absence of further C.sub.2 -C.sub.10 -alk-1-enes at from 50.degree. to 100.degree. C., pressures in the range from 15 to 40 bar and a mean residence time of from 0.5 to 5 hours and subsequently, in a second polymerization stage, a mixture of propylene and further C.sub.2 -C.sub.10 -alk-1-enes is polymerized at from 30.degree. to 100.degree. C., pressures in the range from 15 …