摘要 |
Polycarbonate oligomers are prepared by oxidative carbonylation of a dihydroxyaromatic compound such as bisphenol A in the presence of a catalyst comprising a Group VIII metal such as palladium, an inorganic and/or an organic co-catalyst, a halide source and an alcohol-free solvent comprising at least one liquid aromatic hydrocarbon, optionally in combination with a dipolar aprotic liquid such as N-methylpyrrolidinone. These oligomers may be further polymerized by melt polymerization to precursor polycarbonate oligomers which may be converted to high molecular weight polycarbonates by melt or solid state polymerization. |