| 摘要 |
PROBLEM TO BE SOLVED: To provide aromatic polycarbonates excellent in color tone without deterioration in color tone. SOLUTION: In the process for producing a polycarbonate by transesterification reaction, the transesterification reaction is carried out by selecting reaction temperature T, reaction pressure P, viscosity average molecular weight M of a polycarbonate prepolymer to be obtained, and average residence timeτin such a manner that A in the formula:τ=2.52 A/ 3.816×1010×EXP0.01T×EXP [(-0.009P+(87964P+2.2462×107)M-2.3011)-28.6]) [whereinτis an average residence time (unit:hour); M is a viscosity average molecular weight; P is a reaction pressure (unit:Torr), T is a reaction temperature (unit:K) ; and A is a coefficient] is in the range of 0.8-1.4 to produce a polycarbonate prepolymer which is further polymerized to form a polycarbonate.
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