The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 1998
Filed:
Jun. 27, 1996
Hoechst Aktiengesellschaft, , DE;
Abstract
A process is described for the preparation of polyesters by polycondensation of dicarboxylic acid-diol precondensates (oligomers) at elevated temperature in a liquid heat transfer medium in the presence of customary polycondensation catalysts and, if appropriate, cocondensable modifying agents, wherein the liquid heat transfer medium is inert and free of aromatic structural groups and has a boiling point in the range from 200.degree. to 320.degree. C., wherein the weight ratio of dicarboxylic acid-diol precondensate (oligomers) employed to liquid heat transfer medium is in the range from 20:80 to 80:20 and wherein the polycondensation is carried out in the reaction mixture at 200.degree. to 320.degree. C. in the presence of a dispersion stabilizer. Furthermore, the polyesters and copolyester which can be prepared by the process and their use are described.