Process for the purification of polycarbonate
US9617382B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2014 |
| Grant date | Apr 11, 2017 |
| Priority date | — |
| Expiry date | Jul 25, 2034 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G64/406
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
In an embodiment, a process of purifying a polycarbonate from an interfacial polymerization product mixture comprising an aqueous phase and an organic phase comprising a first organic solvent, the polycarbonate, a catalyst, and ions, the process comprises: separating the aqueous phase and the organic phase to form a separated aqueous feed stream and a separated organic stream; extracting the catalyst and the ions from the separated organic stream to form a purified polycarbonate stream and an extracted aqueous feed stream, wherein at least one of the separated aqueous feed stream and the extracted aqueous feed stream comprise an organic portion and an aqueous portion; purifying an aqueous stream comprising one or both of the separated aqueous feed stream and the extracted aqueous feed stream by adjusting a viscosity of the organic portion to be less than or equal to 40 centipoise by adding a second organic solvent to the aqueous stream to form a combined stream; optionally, adjusting a ratio of the aqueous portion to the organic portion to 1.0 to 20.0 by adding an aqueous solution to the aqueous stream; and separating the combined stream to form a purified aqueous stream, wherein l…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.