| 摘要 |
The present invention relates to a process for the precipitation of aromatic, high-molecular-weight polycarbonates from their solutions in chlorinated hydrocarbons by delayed precipitation by means of methyl ethyl ketones as precipitant or a mixture of methyl ethyl ketone with chlorinated hydrocarbons. The process gives a nicely grained, solvent-free product which can be granulated in an extruder without complications. The invention furthermore relates to a circulation route of the filtrate, in which only a sub-stream need be separated into solvent and precipitant by distillation.
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