Process for producing wholly aromatic polyamide fibers of high strength
US4075269A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1976 |
| Grant date | Feb 21, 1978 |
| Priority date | — |
| Expiry date | Sep 23, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G69/32
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An improved process for preparing wholly aromatic polyamide fibers of high performance charcteristics is provided. The process includes the steps of providing a spinning solution of a wholly aromatic polyamide, the polyamide having a sulfur content as sulfonic acid and/or sulfonate groups attached to the aromatic nuclei of at least 0.5 percent by weight based on the weight of the polyamide; spinning the spinning solution of the wholly aromatic polyamide to produce an as-spun fiber having an inherent viscosity of at least 1.0; and heat treating the as-spun fiber under sufficient tension to maintain a constant length or to elongate the fiber up to about 5 percent of the as-spun length while heating within a range of about 150.degree. C. to about 650.degree. C. The resulting fibers have a tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.