Aminophenoxycyclotriphosphazene cured epoxy resins and the composites, laminates, adhesives and structures thereof

US4668589A · kind A · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• Devendra Kumar · Rochester Hills, US
• George M. Fohlen · Millbrae, US
• John A. Parker · Los Altos, US

Key dates

• Filing date: Nov 21, 1985
• Grant date: May 26, 1987
• Expiry date: Nov 21, 2005

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31525
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Aminophenoxycyclotriphosphazenes such as hexakis(4-aminophenoxy)cyclotriphosphazene and tris(4-aminophenoxy)-tris phenoxyclyclotriphosphazene are used as curing agents for epoxy resins. These 1,2-epoxy resins are selected from di- or polyepoxide-containing organic moieties of the formula (CH.sub.2 --CHO--CH.sub.2).sub.m --W--R--W--(CH.sub.2 CH--CH.sub.2 O).sub.m where R is diphenyldimethylmethane, diphenylmethane, bis(dibromophenyl)dimethylmethane, or ##STR1## W is a nitrogen or oxygen atom; and m is 1 when W is oxygen and 2 when W is nitrogen. The resins are cured thermally in stages at between about 110.degree. to 135.degree. C. for between about 1 and 10 min, then at between about 175.degree. to 185.degree. C. for between about 0.5 to 10 hr and post-cured at between about 215.degree. and 235.degree. C. for between abut 0.1 and 2 hr. These resins are useful for making fire-resistant elevated temperature stable composites, laminates (e.g. graphite fiber or fiberglass), molded parts, and adhesives and structures, usually for aircraft secondary structures and for spacecraft construction.