PURPOSE: To obtain a polycarbonate having excellent hue and heat stability by reacting an aromatic diol with 4 carbonic acid diester in the presence of a specific boron compound as a transesterification catalyst.
CONSTITUTION: This polycarbonate is obtained by reacting (A) an aromatic diol compound such as a compound of formula II [A is single bond and bifunctional 1-15C (substituted)hydrocarbon group, O, S, etc.; X and Y are halogen or 1-6C hydrocarbon group; (p) and (q) are 02] with (B) a carbonic acid diester such as a compound of formula III (Ar is monofunctional aliphatic group or monofunctional aromatic group) in the presence of a boron compound (metal salt) of formula ] [R1 and R2 are 1-4C alkyl or (substituted)phenyl; M is alkaline (earth) metal compound; (n) is 0-4] as a transesterification catalyst.
HAYASHI KATSUSHIGE
HONDA HISASHI
HIRASHIMA ATSUSHI
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