Production of polycaproamide fiber from polycaproamide reacted with cyclic tetracarboxylic acid dianhydride
US4061621A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 10, 1975 |
| Grant date | Dec 6, 1977 |
| Priority date | — |
| Expiry date | Oct 10, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G69/14
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
It has been suggested that a high strength polycaproamide fiber having excess number of carboxyl end groups over amino end groups can be produced by melt spinning a polymer prepared by polymerizing e-caprolactam and reacting the polymer with a dibasic carboxylic acid containing at least six carbon atoms. However, with incorporation of this dicarboxylic acid reactant in continuous operation, serious problems have been encountered in melt-spinning of the polymer due to the frequent occurrence of "nubs" or enlarged places in the extruded polyamide filament. It has now been found that the occurrence of said nubs in the fiber can be greatly reduced by utilizing certain cyclic tetracarboxylic acid dianhydrides and reacting the dianhydride at the end of the polymerization. Moreover, dyeing properties of the fiber may be more readily controlled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.