Patent · US Expired

Method for producing an aromatic polycarbonate

US7479258B2 · kind B2 · utility

3Cited by
6References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 14, 2005
Grant dateJan 20, 2009
Priority date
Expiry dateDec 16, 2025

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01J2219/1946
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

It is a task of the present invention to provide a method for producing a high quality, high performance aromatic polycarbonate (which is colorless and has excellent mechanical properties) from a molten aromatic polycarbonate prepolymer obtained by reacting an aromatic dihydroxy compound with a diaryl carbonate, wherein the polycarbonate can be stably produced on a commercial scale at 1 to 50 t/hr for a long time. In the present invention, this task has been accomplished by a method for producing an aromatic polycarbonate by the melt transesterification process, in which the prepolymer is polymerized by a guide-wetting fall polymerizer device having a specific structure, whereby a high quality, high performance aromatic polycarbonate as mentioned above can be stably produced on a commercial scale at 1 to 50 t/hr for a long time (more than several thousand hours, e.g., more than 5,000 hours) without fluctuation of the molecular weight thereof.

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