Patent · US Expired

Method for producing polycarbonates

US6887970B2 · kind B2 · utility

7Cited by

9References

11Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Silke Kratschmer · Krefeld, DE
Uwe Hucks · Alpen, DE
Michael Prein · Brasschaat, BE

Key dates

Filing date	Mar 13, 2002
Grant date	May 3, 2005
Priority date	—
Expiry date	Mar 13, 2022

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08G64/307
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

The invention relates to a continuous method for producing polycarbonates by transesterifying diaryl carbonates with dihydroxyaryl compounds in the presence of quaternary onium compounds. The invention also relates to polycarbonates produced thereby and products produced from said polycarbonates.

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