Elastic fabric comprising a polyurethane elastic fiber made from a polyether based polyol

Abstract

To provide elastic fabric that has comfortable wear and fit even in thin and light fabric by using a high-powered polyurethane elastic fiber that has at least 1.5 times the active force and recovery per unit fineness at the time of 100 to 200% elongation compared to conventional polyurethane elastic fiber. Resolution means an elastic fabric comprising a polyurethane elastic fiber made of a polyol, with a molecular weight between 450 and 1600 with a ratio of weight average molecular weight to number average molecular weight of at least 1.8, an organic diisocyanate compound, and a diamine compound.

Claims

1. An elastic fabric comprising a polyurethane elastic fiber made of a polyether based polyol with a minimum number average molecular weight of about 450 and a maximum of about 1600, an organic diisocyanate compound, and a diamine compound, wherein the reaction equivalent ratio (molar ratio or capping ratio) of the organic diisocyanate compound to the polyol is in the range of 1.3:1 to 1.7:1.

2. The elastic fabric according to claim 1, wherein the ratio of the weight average molecular weight to the number average molecular weight of the polyol is a minimum of 1.8:1.

3. The elastic fabric according to claim 1, wherein a polyol of low molecular weight is blended with a polyol of high molecular weight.

4. The elastic fabric according to claim 1, wherein the reaction equivalent ratio (molar ratio or capping ratio) of the organic diisocyanate compound to the polyol is in the range of 1.4:1 to 1.6:1.

5. The elastic fabric according to claim 1, wherein the polyurethane elastic fiber is spun from a solution-polymerized polyurethane polymer solution by the prepolymer method.

6. The elastic fabric according to claim 1, wherein the polyurethane polymer is derived from a diamine compound and has a terminal group concentration of 5 to 50 meq/kg.

7. The elastic fabric according to claim 1, wherein the number average molecular weight of the polyurethane polymer is between 40000 to 150000 calculated with polystyrene as the standard.

8. The elastic fabric according to claim 1, wherein the polyurethane elastic fiber is spun by dry spinning the polyurethane polymer solution.

9. The fabric according to claim 1 wherein the polyurethane has a % NCO range of the prepolymer of 2.6 to 3.8.

Description

EXAMPLES

(1) The present invention will be described in detail using the following examples. However, the present invention is not restricted by these embodiments.

(2) Measurement of the Active Force and Recoverability of the Polyurethane Elastic Fiber

(3) The polyurethane elastic fiber was measured by using an Instron 550 tensile strength testing machine to get the active force and recoverability of the polyurethane elastic fiber.

(4) A 5 cm length of test material was stretched 200% at a tensile strength of 50 cm/min and repeated 5 times. The active force of the first time and the active force and recoverability of the fifth time were measured.

(5) Creation and Evaluation of the Elastic Fabric

(6) A 44 dtex polyurethane elastic fiber was elongated to three times its length and covered with a polyamide processed yarn (trademark Kupe made by Toray, Inc. 33 DTEX, 26 Filaments) at a twist rate of 800 T/m, to make a single covered yarn (SCY) with S-twists and Z-twists.

(7) In addition, S-twist SCY is fed into a feed opening 1,3 of a Panst knitting machine (Lonati, 400 needle count) at 1.0 g knitting tension, and the Z-twist SCY is fed into a 2,4 opening to knit knitted fabric.

(8) Next, dye processing of the knit fabric is performed as indicated below to obtain knitted tights.

(9) (1) Preset: vacuum dried, 90 C.10 min.

(10) (2) Dye; 2.0 owf % of Laneset (registered trademark) Black B is used for the dye made by Chiba Specialty Chemicals, Inc. and processed for 60 min at 90 C. to dye black. Acetic acid and ammonium sulfate were implemented for pH adjustment at the time of dying.
(3) Finally, softening processing is performed and completed through set processing (Panst Setting Machine, Set: 115 C.10 sec, dry; 120 C.30 sec).

(11) The stretch ability and support strength of the obtained knitted fabric underwent the following sensory evaluations.

(12) Stretch Ability Evaluation Points 3: Excellent stretch ability

(13) 2: Slightly lacking stretch ability 1: Lacks stretch ability
Support Strength Evaluation Points: 3: Excellent support 2: Slightly lacking support 1: Lacks Support

Example 1

(14) A prepolymer is obtained by reacting 390 g of polytetramethylene ether glycol (PTMEG) with a molecular weight of 1000 with 151.12 g of 4,4-diphenylmethane diisocyanate (MDI) in a nitrogen atmosphere in a nonsolvent state at 80 C. for 3 hours. The residual isocyanate group after the reaction was 3.33 wt %.

(15) 540 g of the obtained prepolymer is dissolved in 1166 g of DMAc, and the chain extender solution in which 132.48 g of 10 wt % ethylenediamine/DMAc solution is blended with 9.76 g of 10 wt % diethylamine/DMAc solution is added while stirring vigorously at 40 C. to obtain a viscosity adjusted polymer solution of 30 wt % concentration. The terminal group concentration derived by the diamine compound of this polymer solution was 24 meq/kg.

(16) A polyurethane solution generated by reacting t-butyldiethanolamine with methylene-bis(4-cyclohexylisocyanate) is blended with a condensation polymer of p-creosol and divinyl benzene in a 2 to 1 weight ratio into this polyurethane polymer solution, then DMAc is added, to prepare a 30 wt % additive solution. 96 parts by weight of the polyurethane polymer solution is blended with 4 parts by weight of the additive solution to make the spinning concentrate solution. This is dry spun at a speed of 650 m/min with a speed ratio for the Godet roller to winding machine at 1.25 to obtain a 33 DTEX 4 filament yarn.

(17) The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the obtained knit fabric are shown in Table 2.

(18) TABLE-US-00001 TABLE 1 Comp Comp Comp Comp Comp Ex 1 Ex 2 Ex 3 Ex 4 Ex 5 Ex 6 Ex 1 Ex 2 Ex 3 Ex 4 Ex 5 PTMG molecular 1000 1000 650 1400 1400 1200 1800 1800 1800 1800 1800 weight Molecular weight 2.6 2.6 2.4 2.6 2.6 2.5 8.0 2.0 2.0 2.0 2.1 ratio Molecular weight 6.95 6.95 7.66 2.95 2.95 3.06 1.77 1.77 1.77 1.77 4.66 distribution Diamine 24 meq/ 24 meq/ 19.5 meq/ 31 meq/ 31 meq/ 26 meq/ 28 meq/ 28 meq/ 40 meq/ 40 meq/ 24 meq/ terminal group kg kg kg kg kg kg kg kg kg kg kg concentration Polymer weight 108000 108000 106000 118000 118000 120000 112000 112000 103000 103000 121000 average molecular weight Fineness (DTEX) 44 22 22 44 22 22 44 22 44 22 22 1 cycle 100% 4.2 2.1 2.5 3.5 1.7 1.8 2.2 1.1 2.0 1.0 2.1 stress (cN) 1 cycle 200% 7.9 4.0 6.8 8.0 3.9 4.0 5.0 2.5 5.1 2.5 3.9 stress (cN) 5 cycle 100% 3.5 1.8 1.7 2.2 1.1 1.1 1.4 0.7 1.3 0.6 0.7 stress (cN) 5 cycle 200% 6.6 3.4 3.2 6.9 3.3 3.4 4.3 2.1 4.1 2.0 3.3 stress (cN) 5 cycle 100% 1.5 0.8 0.8 1.6 0.8 0.8 1.0 0.5 0.9 0.4 0.5 recovery (cN) 5 cycle 200% 5.0 2.6 2.6 5.6 2.6 2.7 3.5 1.7 3.3 1.7 2.0 recovery (cN) Breaking 430 430 390 460 450 440 470 470 440 435 410 elongation (%) Breaking 0.9 0.9 0.7 1.0 1.0 1.0 1.0 1.0 0.9 0.9 0.7 strength (cN/DTEX)

(19) TABLE-US-00002 TABLE 2 Support Fineness Stretch Ability Strength Overall (DTEX) Evaluation Evaluation Evaluation Example 1 44 2.5 3.0 5.5 Example 2 22 2.5 2.2 4.7 Example 3 22 2.4 2.0 4.4 Example 4 44 2.8 3.0 5.8 Example 5 22 2.6 2.2 4.8 Example 6 22 2.8 2.4 5.2 Comparative 44 2.7 2.4 5.1 Example 1 Comparative 22 2.6 1.0 3.6 Example 2 Comparative 44 2.7 2.6 5.3 Example 3 Comparative 22 2.4 1.0 3.4 Example 4 Comparative 22 1.2 1.8 3.0 Example 5

Example 2

(20) With the exception of using PTMEG adjusted to a molecular weight of 1000 by blending 35 parts by weight of PTMEG with a molecular weight of 650 with 65 parts by weight of PTMEG with a molecular weight 1400, spinning was performed to prepare spinning concentrate solution by adding an additive solution to the polymerized polyurethane polymer solution under the same conditions as Example 1.

(21) The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the knit fabric are shown in Table 2.

Example 3

(22) A prepolymer is obtained by reacting 390 g of PTMEG with a molecular weight of 650 with 210 g of MDI in a nitrogen atmosphere in a nonsolvent state at 80 C. for 3 hours. The residual isocyanate group after the reaction was 3.36 wt %.

(23) 600 g of the obtained prepolymer is dissolved in 1294.78 g of DMAc, and the chain extender solution in which 149.04 g of 10 wt % ethylenediamine/DMAc solution is blended with 8.78 g of 10 wt % diethylamine/DMAc solution is added while stirring vigorously at 40 C. to obtain a viscosity adjusted polymer solution of 30 wt % concentration. The terminal group concentration derived by the diamine compound of this polymer solution was 19.5 meq/kg.

(24) The additive solution was blended into the polyurethane polymer solution in the same manner as Example 1 to prepare a spinning concentrate solution and perform spinning. The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the knit fabric are shown in Table 2.

Example 4

(25) A prepolymer is obtained by reacting 400 g of PTMEG with a molecular weight of 1400 with 121.42 g of MDI in a nitrogen atmosphere in a nonsolvent state at 80 C. for 3 hours. The residual isocyanate group after the reaction was 3.22 wt %.

(26) 520 g of the obtained prepolymer is dissolved in 1122.66 g of DMAc, and the chain extender solution in which 123.86 g of 10 wt % ethylenediamine/DMAc solution is blended with 12.16 g of 10 wt % diethylamine/DMAc solution is added while stirring vigorously at 40 C. to obtain a viscosity adjusted polymer solution of 30 wt % concentration. The terminal group concentration derived by the diamine compound of this polymer solution was 31 meq/kg.

(27) The additive solution was blended into the polyurethane polymer solution in the same manner as Example 1 to prepare a spinning concentrate solution and perform spinning. The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the knit fabric are shown in Table 2.

Example 5

(28) With the exception of using PTMEG adjusted to a molecular weight of 1400 by blending 50 parts by weight of PTMEG with a molecular weight of 1000 with 50 parts by weight of PTMG with a molecular weight 1800, spinning was performed to prepare spinning concentrate solution by adding an additive solution to the polymerized polyurethane polymer solution under the same conditions as Example 4.

(29) The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the knit fabric are shown in Table 2.

Example 6

(30) A prepolymer is obtained by reacting 400 g of PTMEG adjusted to a molecular weight of 1200 by blending 62.5 parts by weight of PTMEG with a molecular weight of 1000 with 37.5 parts by weight PTMEG with a molecular weight of 1800, with 137.50 g of MDI in a nitrogen atmosphere in a nonsolvent state at 80 C. for 3 hours. The residual isocyanate group after the reaction was 3.38 wt %.

(31) 535 g of the obtained prepolymer is dissolved in 1152.04 g of DMAc, and the chain extender solution in which 133.92 g of 10 wt % ethylenediamine/DMAc solution is blended with 10.52 g of 10 wt % diethylamine/DMAc solution is added while stirring vigorously at 40 C. to obtain a viscosity adjusted polymer solution of 30 wt % concentration. The terminal group concentration derived by the diamine compound of this polymer solution was 26 meq/kg.

(32) The additive solution was blended into the polyurethane polymer solution in the same manner as Example 1 to prepare a spinning concentrate solution and perform spinning. The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the knit fabric are shown in Table 2.

Comparative Example 1

(33) A prepolymer is obtained by reacting 400 g of PTMEG with a molecular weight of 1800 with 87.78 g of MDI in a nitrogen atmosphere in a nonsolvent state at 90 C. for 2 hours. The residual isocyanate group after the reaction was 2.22 wt %.

(34) 485 g of the obtained prepolymer is dissolved in 1071.67 g of DMAc, and the chain extender solution in which 79.58 g of 10 wt % ethylenediamine/DMAc solution is blended with 10.41 g of 10 wt % diethylamine/DMAc solution is added while stirring vigorously at 40 C. to obtain a viscosity adjusted polymer solution of 30 wt % concentration. The terminal group concentration derived by the diamine compound of this polymer solution was 28 meq/kg.

(35) The additive solution was blended into the polyurethane polymer solution in the same manner as Example 1 to prepare a spinning concentrate solution and perform spinning. The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the knit fabric are shown in Table 2.

Comparative Example 2

(36) A prepolymer is obtained by reacting 400 g of PTMEG with a molecular weight of 1800 with 105.56 g of MDI in a nitrogen atmosphere in a nonsolvent state at 90 C. for 2 hours. The residual isocyanate group after the reaction was 3.32 wt %.

(37) 505 g of the obtained prepolymer is dissolved in 1084.80 g of DMAc, and the chain extender solution in which 124.06 g of 10 wt % ethylenediamine/DMAc solution is blended with 16.24 g of 10 wt % diethylamine/DMAc solution is added while stirring vigorously at 40 C. to obtain a viscosity adjusted polymer solution of 30 wt % concentration. The terminal group concentration derived by the diamine compound of this polymer solution was 40 meq/kg.

(38) The additive solution was blended into the polyurethane polymer solution in the same manner as Example 1 to prepare a spinning concentrate solution and perform spinning. The properties of the obtained yarn are shown in Table 1, and the results of sensory evaluation for stretch ability and support strength for the knit fabric are shown in Table 2.

(39) For Examples 7-19 the following test methods were used:

(40) The NCO content of the capped glycols was determined according to the method of S. Siggia, Quantitative Organic Analysis via Functional Group, 3rd Edition, Wiley & Sons, New York, pages 559-561 (1963).

(41) The strength and elastic properties of the spandex fibers were measured in accordance with the general method of ASTM D 2731-72. Three threads, a 2-inch (5-cm) gauge length and a 0-300% elongation cycle were used for each of the measurements. The samples were cycled five times at a constant elongation rate of 50 centimeters per minute. Load power (TP2), the stress on the spandex during initial extension, was measured on the first cycle at 200% extension and is reported as grams/denier. Unload power (TM2) is the stress at an extension of 200% for the fifth unload cycle and is also reported in grams/denier. Percent elongation at break (ELO) and tenacity (TEN) were measured on a sixth extension cycle. Percent set was also measured on samples that had been subjected to five 0-300% elongation/relaxation cycles. The percent set, % Set, was then calculated as
% Set=100(L.sub.fL.sub.o)/L.sub.o,
where Lo and Lf are respectively the filament (yarn) length when held straight without tension before and after the five elongation/relaxation cycles.

(42) Additionally, instead of 0-300% stretch cycles, the spandex threads of 140 denier were stretched and cycled to a fixed tension, e.g., 15 grams of force. The stress-strain properties including load power, unload power and % Set were measured and recorded.

(43) Alternatively, the tensile properties of the spandex fibers were measured in the first cycle to the breaking point using an Instron tensile tester equipped with a Textechno grip. The load power at 200% stretch (TT2), breaking elongation (TEL) and breaking tenacity (TTN) were recorded.

Example 7

(44) To a 2000 ml Pyrex glass reaction kettle, which was equipped with an air pressure driven stirrer, a heating mantle and a thermocouple temperature measurement, was charged 250.0 grams of Terathane 1000 glycol (commercially available from Invista, S. . r. L., of Wichita, Kans. and Wilmington, Del.) and 93.88 grams of molten Isonate 125MDR (commercially available from the Dow Company, Midland, Mich.). The reaction mixture was stirred and heated to 90 C. in a glove box with nitrogen atmosphere, and was held at this temperature for 120 minutes with continuous stirring to complete the reaction for the formation of the prepolymer. The NCO content, or % NCO, of the capped glycol prepolymer was determined to be 2.962. To the viscous prepolymer, 628.91 grams of N,N-dimethylacetamide (DMAc) was added with vigorous stirring. Once the prepolymer was fully dissolved in the solvent, a mixture of 123.35 grams of the chain extender solution (containing ethylenediamine and 2-methyl-1,5-pentanediamine at the mole ratio of 90 to 10) and 4.75 grams of the chain terminator solution (containing diethylamine), both at the concentration of 2.0 miliequivalent per gram of DMAc solution, was added into the diluted and dissolved prepolymer solution within 10 seconds with stirring. The resulted viscous polymer solution was allowed to mix for another 15 minutes through continued stirring, and was then stored in a Nalgene plastic bottle for spinning into fibers.

Example 8

(45) Same procedures and ingredients as Example 7 were used to prepare Example 8 polymer solution, except for the changes in ingredient quantities and the determined % NCO of the prepolymer as shown below:

(46) TABLE-US-00003 Terathane 1000 250.00 grams Isonate 125MDR 100.12 grams Determined % NCO 3.505% DMAc 622.13 grams Extender solution 148.32 grams Terminator solution 5.04 grams

Example 9

(47) Same procedures and ingredients as Example 7 were used to prepare Example 9 polymer solution, except for the changes in ingredient quantities and the determined % NCO of the prepolymer as shown below:

(48) TABLE-US-00004 Terathane 1000 250.00 grams Isonate 125MDR 96.99 grams Determined % NCO 3.235% DMAc 625.17 grams Extender solution 135.73 grams Terminator solution 5.35 grams

Example 10

(49) Same procedures and ingredients as Example 7 were used to prepare Example 10 polymer solution, except for the changes in ingredient quantities and the determined % NCO of the prepolymer as shown below:

(50) TABLE-US-00005 Terathane 1000 250.00 grams Isonate 125MDR 90.73 grams Determined % NCO 2.665% DMAc 632.51 grams Extender solution 110.82 grams Terminator solution 4.35 grams

Example 11

(51) Same procedures and ingredients as Example 7 were used to prepare Example 11 polymer solution, except that Terathane650 glycol (commercially available from Invista, S. . r. L., of Wichita, Kans. and Wilmington, Del.) was used instead of Terathane1000. Accordingly, changes in ingredient quantities and the determined % NCO of the prepolymer were also made as shown below:

(52) TABLE-US-00006 Terathane 650 250.00 grams Isonate 125MDR 130.22 grams Determined % NCO 2.818% DMAc 697.78 grams Extender solution 133.78 grams Terminator solution 4.87 grams

Example 12

(53) Same procedures and ingredients as Example 11 were used to prepare Example 12 polymer solution, except that the ingredient quantities and the determined % NCO of the prepolymer were changed as showed below:

(54) TABLE-US-00007 Terathane 650 250.00 grams Isonate 125MDR 135.26 grams Determined % NCO 3.201% DMAc 691.60 grams Extender solution 153.89 grams Terminator solution 5.93 grams

Example 13

(55) Same procedures and ingredients as Example 11 were used to prepare Example 13 polymer solution, except that the chain extender solution, still at the concentration of 2.0 miliequvalent per gram, was made up with a mixture of ethylenedaimine and 2-methyl-1,5-pentanediamine at the mole ratio of 80 to 20. Changes in ingredient quantities and the determined % NCO of the prepolymer were also made as shown below:

(56) TABLE-US-00008 Terathane 650 250.00 grams Isonate 125MDR 135.26 grams Determined % NCO 3.316% DMAc 700.15 grams Extender solution 133.78 grams Terminator solution 4.87 grams

Example 14

(57) Same procedures and ingredients as Example 7 were used to prepare Example 8 polymer solution, except that the ingredient quantities and the determined % NCO of the prepolymer were changed as showed below:

(58) TABLE-US-00009 Terathane 650 250.00 grams Isonate 125MDR 140.44 grams Determined % NCO 3.585% DMAc 688.33 grams Extender solution 174.53 grams Terminator solution 7.05 grams

Example 15

(59) Same procedures and ingredients as Example 11 were used to prepare Example 15 polymer solution, except that the chain extender solution, still at the concentration of 2.0 miliequvalent per gram, was made up with ethylenediamine only in DMAc. Changes in ingredient quantities and the determined % NCO of the prepolymer were also made as shown below:

(60) TABLE-US-00010 Terathane 650 250.00 grams Isonate 125MDR 125.33 grams Determined % NCO 2.603% DMAc 669.81 grams Extender solution 114.20 grams Terminator solution 6.129 grams

Example 16

(61) Same procedures and ingredients as Example 15 were used to prepare Example 16 polymer solution, except that the ingredient quantities and the determined % NCO of the prepolymer were changed as showed below:

(62) TABLE-US-00011 Terathane 650 250.00 grams Isonate 125MDR 130.22 grams Determined % NCO 2.845% DMAc 693.59 grams Extender solution 133.78 grams Terminator solution 6.99 grams

Comparative Example 3

(63) Same procedures and ingredients as Example 7 were used to prepare the Comparative Example 3 polymer solution, except that Terathane1800 glycol (commercially available from Invista, S. . r. L., of Wichita, Kans. and Wilmington, Del.) was used instead of Terathane1000. Accordingly, changes in ingredient quantities and the determined % NCO of the prepolymer were also made as shown below:

(64) TABLE-US-00012 Terathane 1800 250.00 grams Isonate 125MDR 58.68 grams Determined % NCO 2.614% DMAc 578.12 grams Extender solution 93.93 grams Terminator solution 3.94 grams

(65) The above polymer solutions made in the laboratory were spun into 40-denier, 3-filament yarns through a drying spinning process. The DMAc solvent was removed with heated nitrogen gas of 400 C. flushing through the spinning cell at a rate of 15 lbs/hr. The cell wall temperatures were controlled between 290 and 210 C. in multiple heating zones. The dried yarn was applied with a lubricating finish and wound up on a tube at the bottom of the spinning cell at the speed of 667 yards per minute (ypm). The tensile properties of the as-spun yarn, after 24 hours ageing on the tube at room temperatures, were measured and given in Table 3 below.

(66) TABLE-US-00013 TABLE 3 EXAM- TP2 TM2 ELO TEN Set TT2 TEL TTN PLES (gpd) (gpd) (%) (gpd) (%) (g) (%) (g) Compara- 0.1027 0.0261 578 1.139 25.50 5.41 517 55.65 tive 3 Example 0.1462 0.0372 476 1.275 36.85 7.21 418 61.34 7 Example 0.1693 0.0367 453 1.001 43.10 9.64 336 37.91 8 Example 0.1488 0.0360 486 1.126 42.56 7.71 397 49.28 9 Example 0.1412 0.0392 450 1.192 32.93 6.70 424 71.68 10 Example 0.3398 0.0359 349 1.127 40.52 15.15 325 63.33 11 Example 0.4092 0.0385 354 1.330 44.81 20.24 292 61.73 12 Example 0.3492 0.0346 346 0.949 45.55 20.12 316 71.85 13 Example 0.4752 0.0307 339 0.908 51.21 24.08 292 63.43 14 Example 0.2743 0.0427 356 1.103 42.70 11.75 340 63.96 15 Example 0.2595 0.0395 372 1.075 45.81 13.51 342 62.28 16

(67) It can be seen that the examples 7-16 of the present invention exhibit significantly higher modulus (load power TP2 and TT2) and higher recovery power (unload power TM2) than the comparative example 3.

Example 17

(68) The polymer solution was made in the same way as Example 9, and it was spun into 140-denier, 10-filament yarn. The heated nitrogen gas delivered to the spinning cell was at 400 C. with a flow rate of 20 lbs/hr. The cell wall temperatures were controlled between 290 and 210 C. in multiple heating zones. The dried yarn was applied with a lubricating finish and wound up on a tube at the bottom of the spinning cell at the speed of 667 yards per minute (ypm).

Example 18

(69) The polymer solution was made in the same way as Example 11, and it was spun into 140-denier, 10-filament yarn using the same spinning conditions as Example 17 except that the wound-up speed was at 600 yards per minute (ypm).

Example 19

(70) The polymer solution was made in the same way as Example 12, and it was spun into 140-denier, 10-filament yarn using the same spinning conditions as Example 18.

Comparative Example 4

(71) The polymer solution was obtained from the commercial production in making LYCRA T162C spandex fibers, and it was spun into 140-denier, 10-filament yarn using the same spinning conditions as Example 17.

Comparative Example 5

(72) The polymer solution was obtained from the commercial production in making LYCRA T127 spandex fibers, and it was spun into 140-denier, 10-filament yarn using the same spinning conditions as Example 17.

(73) The tensile properties of the as-spun 140-denier yarn, after 24 hours ageing on the tube at room temperatures, were measured and given in Table 4.

(74) TABLE-US-00014 TABLE 4 TP2 EXAMPLES (gpd) TM2 (gpd) ELO (%) TEN (gpd) Set (%) Comparative 4 13.96 3.53 525 120.9 22.18 Comparative 5 12.66 3.31 547 104.8 24.15 Example 17 18.01 4.35 433 90.8 42.13 Example 18 28.12 4.64 333 88.1 39.02 Example 19 29.57 4.73 371 110.8 47.19

(75) It can be seen from Table 4 that the examples 17-19 from the present invention have substantially higher modulus (or load power TP2) and higher recovery power (or unload power TM2) in comparison to incumbent commercial products (comparative 4 and 5).