Polyamide acids and polyimides prepared from a mixture of polycarboxylic acid anhydrides
Abstract
Abstract DISCLOSED HEREIN ARE POLYMERIC MATERIALS CHARACTERIZED BY HAVING A PLURALITY OF RECURRING IMIDE LINKAGES AND DIRECT LINKAGES BETWEEN AROMATIC NUCLEI. THESE MATERIALS ARE THE POLYMERIC REACTION PRODUCT OF (1) A POLYCARBOXYLIC ANHYDRIDE HAVING A MOLECULAR STRUCTURE COMPRISING AT LEAST TWO UNITS (D) EACH DERIVED BY THE LOSS OF ONE OR MORE HYDROGEN ATOMS FROM THE NUCLEUS OF AN AROMATIC CARBOXYLIC ANHYDRIDE AND AT LEAST ONE UNIT (E) DERIVED BY THE LOSS OF TWO OR MORE HYDROGEN ATOMS FROM THE NUCLEUS OR THE NUCLEI OF AN AROMATIC COMPOUND CONTAINING ONE OR MORE NUCLEI, AND WHEREIN ANY D UNIT IS LINKED DIRECTLY TO ONE OR MORE E UNITS AND ANY E UNIT IS LINKED DIRECTLY TO AT LEAST TWO UNITS SELECTED FROM D UNITS AND B UNITS, WITH (2) A POLYAMINE CONTAINING TWO OR MORE PRIMARY AMINO GROUPS PER MOLECULE.
Inventors
- 👤 Frank Long
- 👤 Gordon Roy Ensor
Bibliographic Details
Claims Analysis
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