Phosphorus-containing bisimide resins

US4276344A · kind A · utility

Inventors

• Indra K. Varma · Mountain View, US
• George M. Fohlen · Millbrae, US
• John A. Parker · Los Altos, US
• Robert A. Administrator of the National Aeronautics and Space Frosch · La Cañada Flintridge, US

Key dates

• Filing date: Aug 5, 1980
• Grant date: Jun 30, 1981
• Expiry date: Aug 5, 2000

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T442/2984
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Fire-resistant resins particularly useful for making laminates with inorganic fibers such as graphite fibers, are made by (1) condensation of an ethylenically unsaturated cyclic anhydride with a bis(diaminophenyl)phosphine oxide, and (2) by addition polymerization of the bisimide so obtained. Up to about 50%, on a molar basis, of benzophenonetetracarboxylic acid anhydride can be substituted for some of the cyclic anhydride to alter the properties of the products. Graphite cloth laminates made with these resins have shown 800.degree. C. char yields greater than 70% by weight in nitrogen. Limiting oxygen indexes (LOI) of more than 100% have been determined for these resins, as per ASTM D 2863-4.