Low density bismaleimide-carbon microballoon composites
US4135019A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 1977 |
| Grant date | Jan 16, 1979 |
| Priority date | — |
| Expiry date | Mar 16, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31721
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process for the preparation of composite laminate structures of glass cloth preimpregnated with polybismaleimide resin and adhered to a polybismaleimide glass or aromatic polyamide paper honeycomb cell structure filled or partially filled with a syntactic foam consisting of a mixture of bismaleimide resin and carbon microballoons. The carbon microballoons are prepared by pyrolyzing phenolic microballons and subsequently bonded using a 2% bismaleimide solution. The laminate structures are cured for two hours at 477.degree. K and are ahered to the honeycomb bismaleimide adhesive using a pressure of 700kN/m.sup.2 pressure at 450.degree. K. The laminate composite is then post-cured for two hours at 527.degree. K to produce a composite laminate having a density in the range from about 95 kilograms per cubic meter to 130 kilograms per cubic meter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.