Process for the production of high

Claim 1

IN THE PROCES OF PRODUCING HIGHLY POLYMERIC FIBRE AND FILM FORMING POLYCARBONATES BY INTERESTERIFYING REACTION MIXTURES SELECTED FROM THE GROUP CONSISTING OF (A) DICARBONATES SELECTED FROM THE GROUP CONSISITING OF ALIPHATIC, CYCLOALIPHATIC AND AROMATIC DIESTRS OF CARBONIC ACID AND ORGANIC DIHYDROXY COMPOUNDS SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC, CYCLOALIPHATIC AND AROMATIC DIHYDROXY COMPOUNDS, (B) BIS-CARBONATES SELECTED FROM THE GROUP CONSISTING OF BIS-ALKYL, BIS-CYCLOALKYL AND BISARYL CARBONATES OF AROMATIC DIHYDROXY COMPOUNDS AND SAID ORGANIC DIHYDROXY COMPOUNDS, AND (C) SAID BIS-CARBONATES OF AROMATIC DIHYDROXY COMPOUNDS WITH THEMSELVES, AT TEMPERATURES FROM ABOUT 50 TO ABOUT 330*C. IN THE PRESENCE OF A BASIC INTERESTERIFICATION CATALYST UNTIL HIGHLY POLYMERIC POLYCARBONATES ARE OBTAINED, IN IMPROVEMENT WHICH COMPRISES NEUTRALIZING THE BASIC CATALYST AT THE END OF THE INTERESTERIFICATION REACTION BY ADDING TO THE MELT A BASE-NEUTRALIZING COMPOUND SELECTED FROM THE GROUP CONSISTING OF PHENYCHLOROFORMATE, AROMATIC SULFONIC ACID HALIDE W-CHLOROACETOPHENONE, DIALKYL SULPHATE AND AMMONIUM HYDROGEN SULPHATE INANAMOUNT AT LEAST EQUIVALENT TO THE AMOUNT OF THE BASIC CATALYST EMPLOYED IN SAID INTERESTERIFICATION REACTION.