Forming techniques for shaping polyimide foams
US4639343A · kind A · utility
Inventors
Key dates
| Filing date | May 20, 1985 |
| Grant date | Jan 27, 1987 |
| Priority date | — |
| Expiry date | May 20, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249989
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method of re-shaping polyimide and modified polyimide foam sheets into selected shapes. Polyimide foam sheets can be made by any of a number of methods, some of which produce sheets of selected thicknesses directly and others of which produce blocks or buns of foam which are sliced into sheets. A sheet is placed in a mold having the desired configuration, such as a half-pipe. The sheet is compressed to about 0 to 99% of the original thickness with heating of one or both major surfaces of the sheet to a temperature of from about 250.degree. to 320.degree. C. for about 0.5 to 5 minutes. Upon removal from the mold, the polyimide foam is found to be self-supporting and to have taken on the mold shape. A moisture impervious densified skin is found on the heated side(s).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.