Method for the production of polybutylene terephthalate

US6967235B2 · kind B2 · utility

Assignee

• Zimmer, Inc. · US

Inventors

• Eckhard Seidel · Frankfurt, DE
• Fritz Wilhelm · Karben, DE

Key dates

• Filing date: Apr 16, 2002
• Grant date: Nov 22, 2005
• Expiry date: Jun 28, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G63/85
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

In a process of producing PBT, a mixture of BDO and TPA is esterified in the presence of a catalyst solution, and the esterification product is polycondensated. To avoid the formation of deposits in the PBT, the catalyst solution contains 0.05 to 10 wt-% alkyl titanate, 85 to 99 wt-% BDO, 50 to 50,000 ppm bifunctional carboxylic acid equivalents and/or monofunctional hydroxycarboxylic acid equivalents and not more than 0.5 wt-% water.