| 摘要 |
A process is described to make continuos multifilament yarns andstaple fibers from melt processalbe perfluoropolymers at shear rates higher than the published critical shear rate of the polymer. The fibers produced can be made in many geometrices including round, elliptical, angular, hollow, multilobal, sheath/core, segmented pie, islands-in-the-sea, as well as micro fibers. The technology is applicable to many different fiber producing techniques, including melt spinning, melt blowing and spun bonding. Fibers produced can be further processed such as drawing, heat trating, texturing, air entanglin, spot bonding, hydro-entanglin, and calendaring. Any melt processable perfluoropolymer can be used, including those selected fro mthe group consisting of copolymers of tetrafluoroethylene with 1 to 5 mole % of a least one perfluoroalkoxyvinylether where the alkyl group has from 1 to 4 carbon atoms, copolymers of tetrafluoroethylene with 2 to 20 mole % of at least one perfluoroolefin haivng 3 to 8 carbon atoms, at well as copolymers of tetrafluoroethylene and cyclic perfluorinated dioxoles.
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