Manufacture of dihydroxy aromatic compounds by alcoholysis of flame retardant-containing polycarbonate compositions

摘要

The disclosure provides a method for recovering a dihydroxy aromatic compound and a dialkyl carbonate from a polycarbonate-containing composition comprising a polycarbonate and a phosphorus-containing flame retardant. The method comprises heating the composition in the presence of an alcohol and a transesterification catalyst having non-neutralizable groups at a temperature of 70°C to 200°C and a pressure of 50 mbar to 40 bar for a time sufficient to depolymerize the polycarbonate producing a dihydroxy aromatic compound and a dialkyl carbonate.