Preparation of propylene/ethylene polymers of the toughened polypropylene type

US4977210A · kind A · utility

Assignee

• BASF SE

Inventors

• Juergen Kerth · Eisenberg (Pfalz), DE
• Rainer A. Werner · Annaberg-Buchholz, DE
• Ralf Zolk · Bad Dürkheim, DE
• Klaus-Dieter Ruempler · Monsheim, DE
• Guenther Schweier · Friedelsheim, DE
• Rudolf Mueller-Mall · Schifferstadt, DE
• Wolfgang Gruber · Bischofswerda, DE

Key dates

• Filing date: Aug 4, 1989
• Grant date: Dec 11, 1990
• Expiry date: Aug 4, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F297/083
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Propylene/ethylene block copolymers are prepared by a continuous process in which, in each case in an agitated fixed bed of finely divided polymer from the gas phase, first (I) in a first polymerization zone, propylene is homopolymerized by feeding in a Ziegler-Natta catalyst system consisting of (1) a titanium component which contains titanium, magnesium, chlorine and a phthalic acid derivative, (2) an aluminumalkyl component and (3) a silane component, and (II) in a second polymerization zone, a mixture of propylene and ethylene is polymerized with the propylene homopolymer present in the reaction mixture obtained in the first polymerization zone by feeding in the said reaction mixture. In the process, (A) a titanium component (1) is used which is obtained by a method in which (1.1) first, (1.1.1) in a liquid hydrocarbon, (1.1.2) a finely divided magnesium halide, (1.1.3) an alkanol, (1.1.4) a certain phthalic acid derivative and (1.1.5) titanium tetrachloride are reacted with one another under certain conditions, (1.2) the solid intermediate obtained from (1.1) is extracted with titanium tetrachloride or a liquid alkylbenzene until the remaining solid substance has become substa…