Poly(amide-imide) prepreg and composite processing
US4898754A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 1988 |
| Grant date | Feb 6, 1990 |
| Priority date | — |
| Expiry date | May 5, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31721
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method is disclosed for forming poly(amide-imide) prepregs that permits forming void-free composites having residual solvent contents of less than 0.2% by weight. Such composite have improved glass transition temperatures near those of the pure polymer. In a preferred method, a poly(amide-imide) prepreg containing a residual N-methyl-2-pyrrolidone solvent is rapidly heated to about 650.degree. F. to evaporate residual solvent to less than 1.0% by weight. The prepreg is rapidly cooled before the thermoplastic poly(amide-imide) polymer begins to significantly advance in molecular weight. The prepreg may then be layed up to form composite articles that are consolidatable by application of further heat and pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.