Perfluoroisopropylidene dianhydride and polyimides prepared therefrom

Abstract

This invention relates to a novel aromatic dianhydride and more particularly to the use of said dianhydride for the preparation of thermally stable high-molecular weight polymers including, for example, polybenzimidazoles, polypyrrones, polyimides, and the like. This dianhydride is obtained by reacting a stoichiometric amount of a disodium salt of 2,2-bis(4-hydroxyphenyl) hexafluoropropane with 4-chloro-N-phenylphthalimide to obtain an intermediate, 2,2-bis[4-(3,4-phenylphthalimidephenoxy)phenyl] hexafluoropropane, which is oxidized to the corresponding bis[4-(3,4-dicarboxyphenoxy)phenyl]perfluoroisopropylidene dianhydride.

Dependencies are inferred from the claim text.