Thermal enhancement of the purification process for interfacial polycarbonate and copolymer polycarbonates

    公开(公告)号:US09617380B2

    公开(公告)日:2017-04-11

    申请号:US14907369

    申请日:2014-07-25

    CPC classification number: C08G64/403 C08G64/406

    Abstract: In an embodiment, a process of purifying a polycarbonate comprises: polymerizing a dihydroxy compound and a carbonate source via an interfacial reaction in the presence of a catalyst to form a product mixture comprising an aqueous phase and an organic phase, wherein the organic phase comprises the polycarbonate, the catalyst, ions, and a solvent having a boiling point Tb; heating the product mixture to greater than or equal to Tb; separating the aqueous phase and the organic phase at a temperature greater than or equal to Tb to form a separated organic phase and a separated aqueous phase; extracting the catalyst from the separated organic phase; and extracting the ions from the separated organic phase; wherein if a centrifuge is used in the extracting of the catalyst, the extracting of the ions, or both, the process further comprises cooling a stream entering the centrifuge to less than Tb.

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