Wire-wetting fall polymonization process for the production of polycarbonates
US5589564A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 1996 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | Feb 1, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J2219/00162
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method for producing an aromatic polycarbonate comprises feeding to a feeding zone (having a foraminous plate) at least one polymerizing material selected from the group consisting of a) a molten monomer mixture of an aromatic dihydroxy compound and a diaryl carbonate, and b) a molten prepolymer obtained by a process comprising reacting an aromatic dihydroxy compound with a diaryl carbonate, and allowing the polymerizing material to pass downwardly through the foraminous plate and fall along and in contact with a wire through a wire-wetting fall polymerization reaction zone, thereby effecting polymerization of the polymerizing material during the wire-wetting fall thereof. Colorless and high quality aromatic polycarbonates are thus stably produced at a high polymerization rate for a prolonged period of time, using an apparatus which has excellent sealing properties under high vacuum and maintenance of which is easy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.