| 摘要 |
<p>A process for industrially producing a colorless, transparent polycarbonate with a high molecular weight efficiently by the melt polycondensation of a dihydroxy compound with a carbonic diester through transesterification, which comprises preparing a polycarbonate prepolymer in the first-stage reaction and conducting the polycondensation thereof either under the condition of a residence time ranging from 15 to less than 60 minutes or by using at least one self-cleaning twin-screw paddle extruder in the second-stage reaction.</p> |
