Improved transesterification process for the production of polycarbonates
    21.
    发明授权
    Improved transesterification process for the production of polycarbonates 失效
    改进的用于生产聚碳酸酯的酯交换方法

    公开(公告)号:US5444148A

    公开(公告)日:1995-08-22

    申请号:US155391

    申请日:1993-11-19

    IPC分类号: C08G64/20 C08G64/30 C08G64/00

    CPC分类号: C08G64/307 Y02P20/582

    摘要: An improvement to the transesterification process for the production of aromatic polycarbonates is disclosed. Into the melt which contains diphenols, carbonic acid diaryl esters and optionally branching agents and at temperatures of 130.degree. C. to 400.degree. C. and in the presence of catalysts there is mixed or passing thereover inert gas in a quantity of at least 0.5 Nm3 per kg of polycarbonate melt.

    摘要翻译: 公开了用于生产芳族聚碳酸酯的酯交换方法的改进。 在含有二酚,碳酸二芳基酯和任选的支化剂的熔体中,在130℃至400℃的温度下,在催化剂存在下,混合或通过至少为0.5Nm 3的量的惰性气体 每公斤聚碳酸酯熔体。

    Process for preparing diaryl carbonates and the polycarbonates
obtainable therefrom
    24.
    发明授权
    Process for preparing diaryl carbonates and the polycarbonates obtainable therefrom 失效
    制备碳酸二芳酯和由其获得的聚碳酸酯的方法

    公开(公告)号:US5739258A

    公开(公告)日:1998-04-14

    申请号:US804287

    申请日:1997-03-03

    CPC分类号: C08G64/307 C07C68/005

    摘要: The invention relates to a process for preparing a diaryl carbonate by oxidative carbonylation of the basic aromatic hydroxy compound, in which the aromatic hydroxy compound is the one which is eliminated during melt polycondensation of this diaryl carbonate with a bisphenol. Accordingly the invention also relates to the preparation of polycarbonates by melt polycondensation of diaryl carbonates with bisphenols in which the aromatic hydroxy compounds which is eliminated is used again to prepare the diaryl carbonate. In the event that the aromatic hydroxy compound eliminated is also the basic unit in the bisphenol used, proportions of it may be used to prepare both the diaryl carbonate and the bisphenol.

    摘要翻译: 本发明涉及通过碱性芳族羟基化合物的氧化羰基化制备碳酸二芳基酯的方法,其中芳族羟基化合物是在该碳酸二芳基酯与双酚的熔融缩聚期间被消除的。 因此,本发明还涉及通过碳酸二芳基酯与双酚的熔融缩聚制备聚碳酸酯,其中除去的芳族羟基化合物再次用于制备碳酸二芳基酯。 在除去芳族羟基化合物也是所用双酚中的基本单元的情况下,其比例可用于制备碳酸二芳基酯和双酚。

    Process for the preparation of thermoplastic polycarbonates
    27.
    发明授权
    Process for the preparation of thermoplastic polycarbonates 失效
    制备热塑性聚碳酸酯的方法

    公开(公告)号:US5340905A

    公开(公告)日:1994-08-23

    申请号:US191227

    申请日:1994-02-03

    CPC分类号: C08G64/307 C08G64/14

    摘要: A two step solvent-free process for the preparation of polycarbonates having a low degree of branching is disclosed. Accordingly, the process comprise(i) transesterifying in the melt, at temperatures of from 80.degree. to 250.degree. C. and under atmospheric pressure and for a time of up to five hours of diphenols and carbonic acid diaryl esters in the presence of a catalyst to form an oligocarbonate having a weight average molecular weight of from 8,000 to 18,000 and an OH-end group content of from 25 to 50%, and(ii) polycondensing of said oligocarbonate at temperatures of from 250.degree. C. to 295.degree. C. and pressures of from

    摘要翻译: 公开了一种用于制备具有低支化度的聚碳酸酯的两步无溶剂方法。 因此,该方法包括(i)在80℃至250℃的温度和大气压下在熔体中酯交换反应,并在催化剂存在下进行多达5小时的二酚和碳酸二芳基酯的酯交换反应 以形成重均分子量为8,000至18,000,OH-端基含量为25至50%的低聚碳酸酯,和(ii)所述低碳酸酯在250℃至295℃的温度下的缩聚反应。 和压力为<500毫巴至0.01毫巴,所述催化剂以每工具二酚的10-1至10-8工具的催化剂量存在,所述催化剂为选自以下的至少一种: 季铵化合物和季鏻化合物。