| 摘要 |
A practical process for stable production of a high quality/high performance aromatic polycarbonate not stained and having excellent mechanical properties from a dialkyl carbonate and an aromatic dihydroxy compound on an industrial scale in large amount (for example, 1 ton or more per hour) over a prolonged period (for example, 1000 hours or longer, preferably 3000 hours or longer, or still preferably 5000 hours or longer). The production of the aromatic polycarbonate from the dialkyl carbonate and the aromatic dihydroxy compound can be attained by the process comprising the step (I) of producing diphenyl carbonate by using two reactive distillation columns with specified structures, step (II) of obtaining high purity diphenyl carbonate therefrom by using a high boiling point substance separation column (A) and diphenyl carbonate purification column (B) with specified structures, and step (III) of producing an aromatic polycarbonate from a molten prepolymer obtained from an aromatic dihydroxy compound and the high purity diphenyl carbonate with the use of a guide contact flow-down type polymerizer with specified structure, and step (IV) of recycling phenol produced as by-product to the step (I). |
