Process for the preparation of a syndiotactic polyolefin

US5239022A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Andreas Winter · Königstein, DE
• Martin Antberg · Frankfurt am Main, DE
• Walter Spaleck · Bocholt, DE
• Jurgen Rohrmann · Kelkheim, DE
• Volker Dolle · Kelkheim, DE

Key dates

• Filing date: Oct 15, 1992
• Grant date: Aug 24, 1993
• Expiry date: Oct 15, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S526/943
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A very active catalyst system for olefin polymerization is composed of an aluminoxane and a metallocene of the formula I ##STR1## in which, preferably, M.sup.1 is Zr or Hf, R.sup.1 and R.sup.2 are alkyl or halogen, R.sup.3 and R.sup.4 are hydrogen, R.sup.5 and R.sup.6 are alkyl or haloalkyl, --(CR.sup.8 R.sup.9).sub.m --R.sup.7 --(CR.sup.8 R.sup.9).sub.n -- is a single-membered or multimembered chain in which R.sup.7 may furthermore be a (substituted) hetero atom, m+n is zero or 1 and R.sup.10 is hydrogen. The catalyst system gives polymers having high stereospecificity and a high melting point.