Stabilized polyimides
Abstract
Abstract DISCLOSED HEREIN ARE RESIN SYSTEMS CHARACTERIZED BY IMPROVED OXIDATIVE THERMAL STABILITY WHICH ARE OBTAINED BY INCORPORATING A BENEFICIATING STABILIZING ADDITIVE INTO A POLYMER FORMING COMPOSITION COMPRISING (1) AROMATIC POLYCARBOXYLIC COMPONENTS CONTAINING FROM THREE TO FOUR CARBOXYLIC ACID GROUPS PER MOLECULE SELECTED FROM THE GROUP CONSISTING OF FREE POLYCARBOXYLIC ACIDS, ESTERS OF POLYCARBOXYLIC ACIDS AND AMMONIUM SALTS OF POLYCARBOXYLIC ACIDS AND (2) A POLYAMINE COMPONENT HAVING AT LEAST TWO PRIMARY AMINO GROUPS PER MOLECULE. THE BENEFICIATING STAILIZING ADDITIVES USED IN THE PRACTICE OF THE PRESENT INVENTION INCLUDE BORIC ACID, PHOSPHORIC ACID, SULFURIC ACID AND THEIR ACID DERIVATIVES AND ESTERS AND AMMONIUM SALTS OF THE FOREGOINING ACIDS.
Inventors
- 👤 Edward Lavin
- 👤 Albert H Markhart
- 👤 Irving Serlin
- 👤 John R Le Blanc
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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