Production of polycaproamide fiber wherein polycaproamide is reacted with phenylene bis-(3-butane-1,2-dicarboxylic anhydride)
US4075271A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 1976 |
| Grant date | Feb 21, 1978 |
| Priority date | — |
| Expiry date | Oct 27, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G69/48
- 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.