Bicomponent fibers in a sheath-core structure comprising fluoropolymers and methods of making and using same

• US 6,174,601 B1
• Filed: 02/26/1999
• Issued: 01/16/2001
• Est. Priority Date: 09/12/1997
• Status: Expired due to Fees

• Current Assignee: Solvay Solexis SPA (Solvac SA)
• Original Assignee: Ausimont U.S.A., Inc.
• Inventors: Stanitis, Gary E., Fagan, Joseph P.
• Primary Examiner(s): Edwards, N.
• Application Number:
  US09/147,946
• Time in Patent Office: 690 Days
• Field of Search: 428/370, 428/373, 264/172.15, 264/172.11
• US Class Current: 428/373
• CPC Class Codes: D01F 8/06 with at least one polyolefin as constituent
• CPC Class Codes: D01F 8/12 with at least one polyamide as constituent
• CPC Class Codes: D01F 8/14 with at least one polyester as constituent
• CPC Class Codes: Y10T 428/2924 Composite
• CPC Class Codes: Y10T 428/2929 Bicomponent, conjugate, composite or collateral fibers or filaments [i.e., coextruded sheath-core or side-by-side type]

Abstract

A composite, bicomponent, sheath-core fiber (8) and methods of making (FIGS. 1 and 2) and using such fiber by it self or in a multifilament form are described in which the sheath comprises E-CTFE and the core is any spinnable polymer similara to Nylon, PET and copolymers thereof.

Claims

1. A sheath-core bicomponent fiber comprising:

a core component of a first spinnable polymer material, said first polymer material being selected from the group consisting of nylon, nylon and polyester copolymer, and nylon and polyolefin copolymer; and

a sheath component of a second polymer material said second polymer material being selected from the group consisting of a co-polymer of at least ethylene and chlorotrieluoroethylene wherein said co-polymer of ethylene and has a non 1;

1 molar ratio of ethylene to chlorotrifluoroethylene and a volume crystallinity between about 1% and 49%.

2. A sheath-core bicomponent fiber according to claim 1 wherein said sheath component has a volume crystallinity between about 10% and 49%.

3. A sheath-core bicomponent fiber according to claim 1 wherein said sheath component has a volume crystallinity between about 20% and 30%.

4. A sheath core bicomponent fiber according to claim 1 wherein the molar ratio of chlorotrifluoroethylene to ethylene is about 55:

45.

5. A process for forming sheath-core bicomponent fibers of claim 1 suitable for spinning of multifilament yarn bundles of less than 100 denier comprising:

feeding a core component via a first spinnerette plate to a second spinnerette plate in a plurality of individual streams;

enveloping each individual stream of core component in a region between said first and second spinnerette plates with a sheath component fed onto said core component;

feeding composite sheath-core elements through said second spinnerette plate to provide individual sheath-core filaments; and

spinning, drawing and winding up the composite sheath-core filament output of said second spinnerette plate, characterized in that;

said core component is selected from the group consisting of nylon, nylon and polyester copolymer, and nylon and polyolefin copolymer; and

said sheath component is selected from the group consisting of a co-polymer of at least ethylene and chlorotrifluoroethylene.

6. A process according to claim 5 for forming sheath-core bicomponent fibers suitable for spinning of multifilament yarn bundles of less than 100 denier wherein said sheath component has a volume crystallinity between about 10% and 49%.

7. A process according to claim 5 for forming sheath-core bicomponent fibers suitable for spinning of multifilament yarn bundles of less than 100 denier wherein said sheath component has a volume crystallinity between about 1% and 49%.

8. A process according to claim 5 for forming sheath-core bicomponent fibers suitable for spinning of multifilament yarn bundles of less than 100 denier wherein said sheath component has a volume crystallinity between about 20% and 30%.

9. A process according to claim 5 for forming sheath-core bicomponent fibers suitable for spinning of multifilament yarn bundles of less than 100 denier wherein said copolymer of ethylene and chlorotrifluoroethylene has a non 1:

1 molar ratio.

10. A process according to claim 5 for forming sheath-core bicomponent fibers suitable for spinning of multifilament yarn bundles of less than 100 denier wherein the molar ratio of chlorotrifluoroethylene to ethylene is approximately 55:

45.

11. The sheath-core bicomponent fiber according to claim 1 wherein said polyolefin is selected from the group consisting of polyethylene, polypropylene or combinations thereof.

12. A sheath-core bicomponent fiber comprising:

a core component of a first spinnable polymer material, said first polymer material being selected from the group consisting of nylon, nylon and polyester copolymer, and nylon and polyolefin copolymer; and

a sheath component of a second polymer material being a co-polymer of ethylene and chlorotrifluoroethylene and co-polymerizable olefinic monomers for reducing crystallinity of said sheath component wherein said sheath component has a volume crystallinity between about 20% and 30%.

13. The sheath-core bicomponent fiber according to claim 12 wherein said olefinic monomers are fluorinated monomers.