| 摘要 |
<p>Compounds which are bis-(N-alkylphthalimides) are prepared by a new process in which a halogen-containing precursor is heated in the presence of a nickel compound, a reducing agent, for example, metallic zinc, and an organic solvent. The resulting compound is useful in a process for the preparation of copolymer, in which the compound is reacted with alkali to form a tetraacid, the acid is dehydrated to form a dianhydride, and the dianhydride is reacted with a second dianhydride and a diamine under copolymer-forming conditions.</p> |
