Claims
- 1. The method of forming textile yarn filaments including the steps of
- cospinning through an orifice and a hollow needle therein and drawing a core comprising a slurry of particulate sorptive material in a liquid carrier with a surrounding sheath comprising a blend of a polymeric material and an open-cell pore-forming material which is compatible with the polymeric material during cospinning and incompatible therewith to form a discrete phase after leaving the orifice, said drawing reducing the outer diameter of the extrudate to between 0.001 and 0.01 inch,
- extracting the pore-forming material to porosify the sheath of the resulting filament, and
- extracting the liquid carrier from the core of the filament.
- 2. The method according to claim 1, in which the cospinning includes melt-blending the polymeric material and the pore-forming material.
- 3. The method according to claim 1, in which the liquid carrier is selected to exclude low boiling constituents capable of flashing during cospinning.
- 4. The method according to claim 1, in which the slurry comprises activated carbon in triethylene glycol.
- 5. The method according to claim 4, in which the slurry is heated prior to cospinning to a temperature sufficient to cause substantial removal of ethylene glycol traces and water.
- 6. The method according to claim 1, in which the slurry is sieved prior to cospinning.
- 7. The method according to claim 1, in which the pore-forming material is crystallizable.
- 8. The method according to claim 1, in which the pore-forming material comprises paraffin wax.
- 9. The method according to claim 1, in which the pore-forming material comprises between 5 and 50 percent by weight of the melt blend.
- 10. The method according to claim 2, including melt drawing the filament to a ratio exceeding 10:1.
- 11. The method according to claim 1, including spin drawing the filament and thereafter further drawing the filament in a liquid bath.
- 12. The method according to claim 8, in which the paraffin wax is extracted with pentane.
- 13. The method according to claim 4, in which the triethylene glycol is extracted with methanol.
- 14. The method according to claim 4, in which the triethylene glycol is extracted with boiling methanol followed by a furtehr extraction with pentane.
- 15. The method according to claim 1, in which the pore-forming material and liquid carrier are simultaneously extracted.
- 16. The method according to claim 15, in which the pore-forming material comprises paraffin wax, the liquid carrier comprises triethylene glycol, and the wax and triethylene glycol are extracted by a plurality of pentane and methanol washes.
- 17. The method according to claim 15, in which the pore-forming material comprises paraffin wax, the liquid carrier comprises triethylene glycol, and the wax and triethylene glycol are extracted by a plurality of pentane and water washes.
- 18. The method according to claim 4, in which the triethylene glycol is extracted with boiling water followed by drying.
- 19. The method according to claim 1, including the step of drawing the extrudate to a ratio between 2:1 and 20:1 at a temperature below the melting point of the polymeric material.
Parent Case Info
This is a division of application Ser. No. 14,071, filed Feb. 22, 1979 now abandonded.
US Referenced Citations (15)
Non-Patent Literature Citations (2)
Entry |
"Phase Separation Spinning of PP", Williams et al., SPE Journal, vol. 28, pp. 51-57 (1967). |
"Preparation of High Clearance Sorbent-Filled Hollow Fibous", Hein, Gulf South Res. Zustitukerert, (7-77), p. 42. |
Divisions (1)
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Number |
Date |
Country |
Parent |
14071 |
Feb 1979 |
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