PROCESS FOR FORMING SYNTHETIC FIBER AND FIBER, YARNS AND CARPETS PRODUCED THEREBY

Abstract

Processes for forming synthetic fibers from polymer melts containing a first fiber forming polymer, a spin assist additive, and optionally a pigment additive are provided. Also provided are synthetic fibers of a first fiber forming polymer, a spin assist additive, and optionally a pigment additive, as well as articles of manufacture such as yarns, carpets and fabrics made up of these synthetic fibers.

Claims

1. A process for forming a synthetic fiber, said process comprising the steps of: (a) producing a polymer melt comprising a first fiber forming polymer and a spin assist additive, wherein the spin assist additive is present in a range from about 0.5 to about 5 percent by weight; and (b) forming a synthetic fiber from the polymer melt.

2. The process of claim 1, wherein the spin assist additive is a polyamide comprising at least one aliphatic diamine and at least two distinct aromatic dicarboxylic acids, and copolymers and blends thereof.

3. The process of claim 2, wherein the at least one aliphatic diamine is selected from a group consisting of 2-methyl-1,5-pentamethylene diamine, hexamethylene diamine, 2-methyl hexamethylene diamine, 3-methyl hexamethylene diamine, 2,5-dimethyl hexamethylene diamine, 2,2-dimethylpentamethylene diamine, 5-methylnonane diamine, dodecamethylene diamine, 2,2,4- and 2,4,4-trimethyl hexamethylene diamine, 2,2,7,7-tetramethyl octamethylene diamine and diaminodicyclohexyl methane.

4. The process of claim 2, wherein the aromatic dicarboxylic acids are selected from a group consisting of terephthalic acid, isophthalic acid and naphthalene dicarboxylic acid.

5. The process of claim 2, wherein the spin assist additive is selected from the group consisting of nylon DT/DI, nylon DT/6I, nylon DI/6T and nylon 6T/6I, and copolymers and blends thereof.

6. (canceled)

7. (canceled)

8. The process of claim 1, wherein the first fiber forming polymer is selected from the group consisting of a polyamide, polyester, polyolefin and combinations thereof.

9. The process of claim 8, wherein the first fiber forming polymer is polyethylene terephthalate or nylon-6,6.

10. (canceled)

11. The process of claim 1 further comprising addition of a pigment additive to the polymer melt, wherein the pigment additive is an organic or inorganic pigment and the pigment is present in a range from about 0.01 to about 5 percent by weight.

12. (canceled)

13. (canceled)

14. The process of claim 1, wherein forming a synthetic fiber comprises extruding said polymer melt through a spinneret to form one or a plurality of filaments, and drawing the one or a plurality of filaments to form a synthetic fiber.

15. The process of claim 14, wherein the fiber can be drawn at a draw ratio of 2.65 or higher.

16. The process of claim 15, wherein the number of broken filaments observed in a two minute interval while drawing the one or a plurality of filaments to form a synthetic fiber is less than 10.

17. A synthetic fiber comprising: (a) a first fiber forming polymer; and (b) a spin assist additive present in the synthetic fiber at a range from about 0.5 to about 5 percent by weight, wherein the spin assist additive is a polyamide comprising at least one aliphatic diamine and at least two distinct aromatic dicarboxylic acids, and copolymers and blends thereof.

18. (canceled)

19. The synthetic fiber of claim 17, wherein the at least one aliphatic diamine is selected from a group consisting of 2-methyl-1,5-pentamethylene diamine, hexamethylene diamine, 2-methyl hexamethylene diamine, 3-methyl hexamethylene diamine, 2,5-dimethyl hexamethylene diamine, 2,2-dimethylpentamethylene diamine, 5-methylnonane diamine, dodecamethylene diamine, 2,2,4- and 2,4,4-trimethyl hexamethylene diamine, 2,2,7,7-tetramethyl octamethylene diamine and diaminodicyclohexyl methane.

20. The synthetic fiber of claim 17, wherein the aromatic dicarboxylic acids is selected from a group consisting of terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid and 5-sulfoisophthalic acid.

21. The synthetic fiber of claim 17, wherein the spin assist additive is selected from the group consisting of DT/DI, DT/6I, DI/6T and 6T/6I, and copolymers and blends thereof.

22. (canceled)

23. (canceled)

24. The synthetic fiber of claim 21, wherein the spin assist additive does not substantially copolymerize with the first fiber forming polymer.

25. The synthetic fiber of claim 17, wherein the first fiber forming polymer is selected from the group consisting of a polyamide, polyester, polyolefin and combinations thereof.

26. The synthetic fiber of claim 25, wherein the first fiber forming polymer is selected from polyethylene terephthalate and nylon-6,6.

27. (canceled)

28. (canceled)

29. (canceled)

30. (canceled)

31. An article of manufacture comprising the synthetic fiber of claim 26.

32. (canceled)

33. (canceled)

34. (canceled)

Description

EXAMPLES

Example 1

Test Methods

[0053] Test methods used to evaluate the synthetic fibers and yarns produced in accordance with the methods of the present invention included:

[0054] Draw ratio-to-break test: In this test, the draw ratio, which is the ratio of chest roll speed to feed roll speed, is increased till the break of yarn is observed. That ratio-to-break is an indication of the effectiveness of spin assist additive.

[0055] Draw tension test: Yarn draw tension is measured between the feed roll and the draw roll. In general, a lower draw tension indicates improved spinnability.

[0056] The spinning performance was measured by broken filaments/2 minutes. The number of broken filaments was observed by counting the number of flashes observed during the yarn spinning process. Each flash correlated to a broken filament.

Example 2

1245 Denier BCF Pigmented Yarns Extrusion

[0057] A 1245 denier, 68 filament, 4-hole hollowfil, nylon 6,6 yarn was made according to a process well known in the art. Nylon 6,6 copolymer flake was conditioned to the desired RV, and fed into a twin screw extruder running at 190 rpm and a temperature profile of 230 C. at the feed and 285 C. at the discharge. The melted polymer was passed through a heated transfer line, spinning pump and filter pack and then to a spinneret which formed the polymer into individual filaments. The total time that the mixture spent in the melt phase was approximately 8 minutes. The filaments were air quenched and then passed by a touch roller where a suitable finish was applied. The finished filaments were then converged in a yarn bundle which was subsequently drawn, passed over heated rolls, bulk textured according the bulk texturing process described by Coon in U.S. Pat. No. 3,525,134, relaxed, and wound onto tubes. The nylon 6,6 base copolymer was then conditioned to 195 C. and remelted using a twin screw extruder. Control fiber (i.e. fiber spun without any additives), and additives nylon DT/6I, nylon DT/DI and nylon 6T/6I were premixed with base nylon, and fed into the extruder. The pigment concentrates and additives were fed through K-tron feeders and BCF yarn was spun using standard procedures.

Example 3

1245 Denier BCF Pigmented Yarns

[0058] A 1245 denier, 68 filament, 4-hole hollowfil, nylon 6,6 yarn was made according to a process well known in the trade: nylon 6,6 flake was fed into a twin screw extruder running at 190 rpm and a temperature profile of 230 C. at the feed and 285 C. at the discharge. The melted polymer was passed through a heated transfer line, spinning pump and filter pack and then to a spinneret which formed the polymer into individual filaments. The total time that the mixture spent in the melt phase was approximately 8 minutes. The filaments were air quenched and then passed by a touch roller where a suitable finish was applied. The finished filaments were then converged in a yarn bundle which was subsequently drawn, passed over heated rolls, bulk textured according the bulk texturing process described by Coon in U.S. Pat. No. 3,525,134, relaxed and wound onto tubes.

[0059] The yarns spun are shown in Table 1.

TABLE-US-00001 TABLE 1 Draw Tension @ Loading Additive Feed Feed Roll DR = 2.65 yarn Chest Roll Item Color ppm Additive rate, ppm DP Wrap (Front TL Only) needed Speed 2A Red 81- 4000 None NA 880 x 1250 1 doff 2425 25% 2B Red 81- 4000 nylon 15,000 878 x 1250 1 doff 2425 25% DT/6I 2C Red 81- 4000 nylon 30,000 790 x 1250 1 doff 2425 25% DT/6I 2D Red 81- 4000 nylon 15,000 890 x 1250 1 doff 2425 25% DT/DI 2E Red 81- 4000 nylon 30,000 875 x 1250 1 doff 2425 25% DT/DI 2F Red 81- 4000 nylon 15,000 875 x 1250 1 doff 2425 25% 6T/6I 2G Red 81- 4000 nylon 30,000 880 x 1250 1 doff 2425 25% 6T/6I

[0060] Draw ratio-to-break tests were performed on these yarns. In these tests, the draw ratio (DR) was varied till the yarn broke. The higher the draw ratio to break, the more robust is the yarn spinning. In addition, the number of flashes seen in hot chest roll over a 2 minute period was recorded for each draw ratio. The lower this number, the more robust is the spinning process. This data is shown in Table 2.

TABLE-US-00002 TABLE 2 DR = 2.65 DR = 2.70 DR = 2.80 DR = 2.90 DR = 3.0 DR = 3.1 DR = 3.2 Item Color BF BF BF BF BF BF BF 2A Red 81- 915 24 898 866 836 808 782 758 25% 2B Red 81- 915 6 898 4 866 4 836 0 808 1 782 4 758 15 25% 2C Red 81- 915 2 898 7 866 1 836 0 808 4 782 2 758 3 25% 2D Red 81- 915 3 898 2 866 6 836 2 808 0 782 4 758 2 25% 2E Red 81- 915 0 898 1 866 0 836 0 808 0 782 0 758 0 25% 2F Red 81- 915 4 898 0 866 2 836 2 808 0 782 0 758 1 25% 2G Red 81- 915 0 898 0 866 0 836 0 808 1 782 1 758 0 25% *BF represents the number of observed flashes in a 2 minute interval. Each flash is understood to represent a broken filament.

[0061] The pigment additive used in these yarns was Red-81 which is difficult to spin. As shown in Table 2, control yarn without spin assist additive had high broken filaments in 2 minutes even at a draw ratio of 2.65. Control yarn could not be spun at any higher draw ratio. However, when using spin assist additives nylon 6T/6I and nylon DT/DI, (see items 2D, 2E, 2F and 2G), fibers could be spun without significant broken filaments even at draw ratios as high as 3.20. This indicates that the spin performance in a commercial machine would be much better upon addition of spin assist additive agents in accordance with the present invention.