Heterocyclic polyimides prepared from heterocyclic diamines
Abstract
Abstract NOVEL, HETEROCYCLIC RING-CONTAINING POLYIMIDES, USEFUL IN THE FORMATION OF FILMS AND FIBERS ARE FORMED BY REACTING AROMATIC TETRACARBOXYLIC ACID ANHYDRIDES WITH DIAMINES HAVING THE FOLLOWING FORMULA N2N-R-NH2 WHEREIN R IS A DIVALENT RADICAL CONTAINING FROM ONE TO TWO BENZOXAZOLE, BENZIMIDAZOLE, OR BENZOTHIAZOLE MOIETIES, SAID DIVALENT RADICAL CONTAINING AT LEAST TWO AROMATIC RING STRUCTURES, THE AMINE GROUPS OF SAID DIAMINE BEING ATTACHED TO AROMATIC CARBON ATOMS LOCATED IN DIFFERENT RING STRUCTURES, IN AN ORGANIC SOLVENT FOR AT LEAST ONE REACTANT AT A TEMPERATURE BELOW 150*C. TO FORM A POLYAMIDE-ACID INTERMEDIATE AND THEN CONVERTING SAID POLYAMIDE-ACID INTERMEDIATE TO THE POLYIMIDE.
Inventors
- 👤 Billy M Culbertson
Bibliographic Details
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