Process for the preparation of heat-stable, antimony-free polyesters of neutral color and the products which can be prepared by this process

US6787630B1 · kind B1 · utility

Assignee

• Arteva North America S.A.R.L. · CH

Inventors

• Ligia Dominguez De Walter · Frankfurt, DE
• Banks Bryan Moore · Spartanburg, US
• Peter Klein · Burns Lake, CA

Key dates

• Filing date: Aug 28, 1995
• Grant date: Sep 7, 2004
• Expiry date: Aug 28, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G63/87
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Process for the preparation of heat-stable, antimony-free polyesters of neutral color and the products which can be prepared by this processA process for the preparation of heat-stable, antimony-free polyesters of neutral color by esterification of aromatic dicarboxylic acids or transesterification of lower aliphatic esters of aromatic dicarboxylic acids with aliphatic diols and subsequent polycondensation in which a possible transesterification is carried out in the presence of 20 to 120 ppm, based on the catalyst metal, of a transesterification catalyst, after the esterification or transesterification has ended, phosphoric acid, phosphorous acid and/or phosphonic acids or a derivative thereof are added to the esterification or transesterification batch as a completing agent in an amount which is 100% of the amount equivalent to the transesterification catalyst employed and up to 99% of the amount equivalent to the cobalt to be employed, up to 80 ppm of cobalt in the form of a cobalt compound are then added to the batch, and the polycondensation is carried out without the addition of antimony, in the presence of 1 to 10 ppm of titanium, which is added in the form of a titanium com…