Method for preparing polyimide and polyimide prepared thereby
    32.
    发明授权
    Method for preparing polyimide and polyimide prepared thereby 有权
    由此制备聚酰亚胺和聚酰亚胺的方法

    公开(公告)号:US07053168B2

    公开(公告)日:2006-05-30

    申请号:US10683226

    申请日:2003-10-10

    IPC分类号: C08G73/00 C08F6/00 C08L79/00

    CPC分类号: C08G73/1028 C08G73/1032

    摘要: A method for preparing a polyimide includes introducing a mixture of an oligomer and a solvent to an extruder, removing solvent via at least one extruder vent, and melt kneading the oligomer to form a polyimide. The polyimide has a low residual solvent content. The method is faster than solution polymerization of polyimides, and it avoids the stoichiometric inaccuracies associated with reactive extrusion processes that use monomers as starting materials.

    摘要翻译: 制备聚酰亚胺的方法包括将低聚物和溶剂的混合物引入挤出机中,通过至少一个挤出机出口除去溶剂,并熔融捏合低聚物以形成聚酰亚胺。 聚酰亚胺的残留溶剂含量低。 该方法比聚酰亚胺的溶液聚合更快,并且避免了使用单体作为起始原料的反应挤出方法的化学计量不准确性。

    Method for removing impurities from oxidation products
    33.
    发明授权
    Method for removing impurities from oxidation products 有权
    从氧化产物中除去杂质的方法

    公开(公告)号:US06670487B1

    公开(公告)日:2003-12-30

    申请号:US10354402

    申请日:2003-01-30

    IPC分类号: C07D30789

    摘要: Disclosed is a method for removing impurities from products derived from oxidation of an ortho-dialkylaromatic compound which comprises at least one step selected from the group consisting of extraction of an aqueous solution comprising aromatic dicarboxylic acid product with an organic solvent and extraction of an organic solution comprising aromatic anhydride product with an aqueous bicarbonate solution for a time period insufficient to allow hydrolysis of anhydride to acid.

    摘要翻译: 公开了一种从邻二烃基芳族化合物的氧化衍生的产物中除去杂质的方法,该方法包括至少一种选自以下的步骤:将芳族二羧酸产物与有机溶剂的水溶液萃取和萃取有机溶液 包括芳族酸酐产物与碳酸氢盐水溶液一段时间不足以使酸酐水解成酸。