Patent ID: 9139701
Filing Date: 2015-09-22
Classification: C08G

Abstract:
1. A method for continuous production of a polycarbonate-polyorganosiloxane copolymer, comprising: (A) withdrawing a polymerization reaction solution obtained by polymerizing a dihydric phenol compound of formula (1), a carbonate precursor, and a polyorganosiloxane of formula (2) in the presence of an alkaline compound aqueous solution and a water-insoluble organic solvent continuously or intermittently from a reactor; (B) separating the polymerization reaction solution withdrawn in the withdrawing (A) into an aqueous phase and a water-insoluble organic solvent phase; and (C) after washing the water-insoluble organic solvent phase separated in the separating (B) with an acidic aqueous solution, separating the resultant into an aqueous phase and a water-insoluble organic solvent phase, wherein a content of the polycarbonate-polyorganosiloxane copolymer in the aqueous phase separated in the separating (C) is controlled to not more than 2% by mass, and a part or the whole of an extract obtained by extracting the aqueous phase separated in the separating (C) with a water-insoluble organic solvent is reused for the withdrawing (A): wherein R X is a single bond, an alkylene group having from 1 to 8 carbon atoms, an alkylidene group having from 2 to 8 carbon atoms, a cycloalkylene group having from 5 to 15 carbon atoms, a cycloalkylidene group having from 5 to 15 carbon atoms, —S—, —SO—, —SO a and b are each independently an integer of from 0 to 4, wherein R Y is a single bond, or an organic residue comprising an aliphatic or aromatic moiety; n is an average repeating number; Z is a halogen atom, —R R Z′ represents an alkylene group having from 1 to 8 carbon atoms, an alkylidene group having from 2 to 8 carbon atoms, a cycloalkylene group having from 5 to 10 carbon atoms, or a cycloalkylidene group having from 5 to 10 carbon atoms; and m is 0 or 1.