Miscible blends of polybenzimidazoles and polyamide-imides having fluorine-containing linking groups and process for preparation of the blends
US5137985A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 22, 1989 |
| Grant date | Aug 11, 1992 |
| Priority date | — |
| Expiry date | Sep 22, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2379/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A miscible blend comprising from about 5 to about 95 weight percent of a polybenzimidazole and from about 95 to about 5 weight percent of a polyamide-imide having fluorine-containing linking groups, total weight percent of the two polymers being 100. A process for preparing the blends comprises dissolving in a mutual solvent from about 5 to about 95 weight percent of the aromatic polybenzimidazole to about 95 to about 5 weight percent of the polyamide-imide having fluorine-containing linking groups, based on the total weight of those polymers and subsequently evaporating the solvent, thereby producing a dried blend of a polybenzimidazole and a polyamide-imide having fluorine-containing linking groups. The blends, particularly in the form of films, fibers or fibrets, may be post-treated with heat or sulfuric acid in order to minimize their shrinkage when subsequently subjected to heat and in order to increase their resistance to solvents and acid. The polyamide-imides having fluorine-containing linking groups are prepared by forming the polycondensation product of one or more aromatic diamines, one or more trifunctional acid anhydride monomers, and one or more tetrafunctional aromat…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.