| 摘要 |
The invention aims at providing a specific process by which a high-quality and high-performance aromatic polycarbonate which is little discolored and is excellent in mechanical properties can be stably produced from a cyclic carbonate and an aromatic dihydroxyl compound industrially on a large scale (e.g., in an amount of at least one ton per hour) over a long period (e.g., over a period of 1000 hours or longer, preferably 3000 hours or longer, still preferably 5000 hours or longer). The aim can be attained by a process for the production of an aromatic polycarbonate from a cyclic carbonate and an aromatic dihydroxyl compound which comprises the step (I) of preparing a dialkyl carbonate and a diol by using a reaction-distillation column having specific structure, the step (II) of preparing a diaryl carbonate by using two reaction-distillation columns having specific structure, the step (III) of purifying the diaryl carbonate to obtain a high-purity diaryl carbonate, the step (IV) of converting a molten prepolymer prepared from an aromatic dihydroxyl compound and the high-purity diaryl carbonate into an aromatic polycarbonate by using a guide-contact flowing down type polymerizer having specific structure, and the step (V) recycling an aromatic monohydroxyl compound formed as by-product to the step (II).
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