| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high-quality arom. polycarbonate resin excellent in color tone and heat stability by using a rare earth element compd. as a catalyst for transesterification of an arom. dihydroxy compd. with a carbonate precursor. SOLUTION: A rare earth element compd. of the formula (wherein Ln is scandium, yttrium, lanthanum, and a lanthanoid element; X is a monovalent or bivalent element, atomic group or substituent; R<1> to R<3> are each a 1-20C alkyl group or an aryl group; and 0<q+r+s<=3; provided that kp+q+r+s=3 wherein k is the valence of X) is used in an amt. of 1×10<-4> to 1×10<-8> mol in terms of rare earth element per mol of an arom. hydroxy compd. as a catalyst for transesterification of the arom. hydroxy compd. with a carbonate precursor to prepare an arom. polycarbonate resin.
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