Method for alcoholysis of acrylonitrile-butadiene-styrene-containing polycarbonate compositions

Abstract

The disclosure provides a method for recovering a dihydroxy aromatic compound and a dialkyl carbonate from a polycarbonate-containing composition comprising a polycarbonate and acrylonitrile-butadiene-styrene. The method comprises heating the composition in the presence of an alcohol and a transesterification catalyst at a temperature of 70° C. to 200° C. and a pressure of 50 mbar to 40 bar in a reactor for a time sufficient to depolymerize the polycarbonate producing a dihydroxy aromatic compound and a dialkyl carbonate; removing the dihydroxy aromatic compound and the dialkyl carbonate from the reactor, the acrylonitrile-butadiene-styrene remaining as a coating on the surfaces of the reactor; adding a solvent to the reactor; and heating the solvent to remove the acrylonitrile-butadiene-styrene from the surfaces of the reactor.

Dependencies are inferred from the claim text.