| 摘要 |
A process for preparing a polycarbonate, which polycarbonate has improved resistance to thermal degradation and improved impact resistance and consists of reacting at least 70 weight percent of a stoichiometric amount of a carbonate precursor such as phosgene with a dihydric phenol such as bisphenol-A while simultaneously adding to the reaction medium an alkali metal hydroxide such as sodium hydroxide to maintain a pH of 6.0 to about 10.0. The pH is then raised to 11.0 by adding sufficient alkali metal hydroxide.
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