Patent · US Expired

Method for producing aliphatic oligocarbonate diols

US6833433B1 · kind B1 · utility

1Cited by

13References

24Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Andreas Schlemenat · Neuss, DE
Jörg Tillack · Bensberg, DE
Jörg Laue · Olfen, DE
Herbert Witossek · Leipzig, DE

Key dates

Filing date	Dec 4, 2002
Grant date	Dec 21, 2004
Priority date	—
Expiry date	Feb 13, 2023

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08G18/44
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

A process for the production of aliphatic oligocarbonate diols is disclosed. The optionally catalyzed high yield process entails the multistage transesterification of aliphatic diols with dimethyl carbonate. In the process DMC-methanol mixtures that have been distilled off are recycled to the reaction solution with further conversion and depletion of the contained DMC in the same or in a following reaction batch.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.