Process for the production of thermoplastic polycarbonates
    93.
    发明授权
    Process for the production of thermoplastic polycarbonates 失效
    用于生产热塑性聚碳酸酯的方法

    公开(公告)号:US5373082A

    公开(公告)日:1994-12-13

    申请号:US155309

    申请日:1993-11-19

    CPC分类号: C08G64/30

    摘要: A process for the production of polycarbonates by melt transesterification is disclosed. Accordingly, polycarbonate waste is dissolved in monophenols and at an elevated temperature and in the presence of a catalyst degraded to yield oligocarbonates, diaryl carbonates and diphenols. Following the optional separation of fillers and other additives there is produced by partial recondensation and the distillation of monophenol a higher viscosity oligocarbonate having a OH and aryl carbonate terminal groups and a weight average molecular weight of 8000 to 18000, the oligocarbonate thus produced is then polycondensed to form a polycarbonate resin.

    摘要翻译: 公开了通过熔融酯交换法生产聚碳酸酯的方法。 因此,将聚碳酸酯废物溶解在单酚中并在升高的温度下并在催化剂存在下降解以产生低聚碳酸酯,碳酸二芳基酯和二酚。 在填充剂和其它添加剂的任选分离之后,通过部分重新缩合和单酚蒸馏产生具有OH和芳基碳酸酯末端和重均分子量为8000至18000的较高粘度的低聚碳酸酯,然后将如此生产的低聚碳酸酯进行缩聚 以形成聚碳酸酯树脂。