Patent ID: 6323302
Filing Date: 2001-11-27
Classification: C08G

Abstract:
A method for producing a polycarbonate which comprisesa) supplying an aromatic dihydroxy compound powder and a carbonic acid diester into a raw material melting vessel through a transportation piping positioned directly before said raw material melting vessel wherein 90 volume % or more of atmospheric gas in the transportation piping is a non-oxidizing gas and wherein a linear velocity thereof is 0.5 cm/min. or higher;b) mixing and melting said aromatic dihydroxy compound powder and carbonic acid diester;c) followed by initiating a melt polymerization reaction in the presence or absence of a catalyst,wherein pressure of a gas phase of the raw material melting vessel is kept at 0 MPa to 0.05 MPa as gauge pressure.