JP4362803B2 - Polyurethane elastic fiber and method for producing the same - Google Patents

Description

【００９４】
【発明の効果】
本発明によれば、低温においても弾性的性質が損なわれず、ヘタリのない優れた低温特性を有し、かつ、良好な伸長性と回復性を兼ね備え、しかも熱セット性の良好なポリウレタン弾性繊維を得ることができる。本発明のポリウレタン弾性繊維を衣服などに使用した際、フィット性、外観品位、着用性、着用感などに優れたものを得ることができる。これらの優れた特性を有することから、単独での使用はもとより、各種繊維との組み合わせにより、例えばソックス、ストッキング、丸編、トリコット、水着、スキーズボン、作業服、煙火服、洋服、ゴルフズボン、ウエットスーツ、ブラジャー、ガードル、手袋や靴下をはじめとする各種繊維製品の締め付け材料、紙おしめなどサニタニー品の漏れ防止用締め付け材料、防水資材の締め付け材料、似せ餌、造花、電気絶縁材、ワイピングクロス、コピークリーナー、ガスケットなど、種々の用途に展開可能である。[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a polyurethane elastic fiber having excellent elastic properties that do not become sticky even at a low temperature, and having good stretchability and recoverability, and a method for producing the same.
[0002]
[Prior art]
Elastic fibers are widely used for stretchable clothing and industrial materials such as legwear, innerwear, and sportswear because of their excellent stretch properties.
[0003]
Polyurethane elastic fibers are used as such elastic fibers, and a copolymer of tetrahydrofuran and 3-methyltetrahydrofuran is disclosed in JP-A-63-235320, JP-A-5-239177, and JP-A-2-19511. A technique for spinning a polyurethane polymer composed of an organic diisocyanate and a diamine compound is disclosed.
[0004]
[Problems to be solved by the invention]
However, polyether-based polyurethane elastic fibers exhibit excellent rubber elasticity at room temperature, but when the environmental temperature decreases, the rubber elasticity decreases, and when knitting is performed in a low temperature environment in winter, the temperature changes. There has been a problem that the dimensions of the knitted product fluctuate and the finished product is not uniform.
[0005]
Also, at low temperatures, for example, temperatures below 0 ° C., the rubber elasticity is impaired, so it could not be used for materials such as aquaculture knitting that could be used under sub-freezing conditions. .
[0006]
Accordingly, there has been a demand for improvement in the elastic recovery characteristics (cold resistance) of polyether-based polyurethane elastic fibers at low temperatures.
[0007]
Furthermore, in the prior art, when an elastic fiber is used for clothes or the like, the appearance quality, fit, wearability, and wearing feeling are not improved.
[0008]
The present invention provides a product that has excellent elastic properties that are not stubborn even in a low temperature environment, and that is superior in appearance quality, fit, wearability, wear feeling, etc., that could not be obtained by conventional techniques. It is an object of the present invention to provide a polyurethane elastic fiber that can be manufactured and a method for producing the same.
[0009]
[Means for Solving the Problems]
The polyurethane elastic fiber of the present invention employs the following means in order to solve the above problems.
[0010]
That is, the main component is a polyol, a polyurethane is diisocyanate and ethylene glycol, a polyurethane elastic fiber characterized in that the polyol is a random copolymer of tetrahydrofuran and ethylene-oxa i de.
[0011]
Moreover, in order to solve the said subject, the manufacturing method of the polyurethane elastic fiber of this invention employ | adopts the following means.
[0012]
That is, a random copolymer of tetrahydrofuran and ethylene-oxa Lee de polyol, in the production method of polyurethane elastic fiber of polyurethane as a main constituent diisocyanate and ethylene glycol, characterized in that spinning a polyurethane solution as a solute is there.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the polyurethane elastic fiber of the present invention will be described in more detail.
[0014]
The polyurethane elastic fiber of the present invention is a polyurethane whose main constituent components are polyol, diisocyanate and diol.
[0015]
The method for synthesizing the polyurethane is not particularly limited. In particular, it is preferable to perform polymerization in a solution from the viewpoint of efficiently performing the reaction. In addition, trifunctional or higher polyfunctional glycols or isocyanates may be used as long as the effects of the present invention are not hindered.
[0016]
Here, the typical structural unit which comprises the polyurethane in this invention is demonstrated.
[0017]
Polyols for use in the present invention has excellent cold resistance and high extensibility, and, from the viewpoint of obtaining those equipped with a high recovery, tetrahydrofuran (hereinafter, abbreviated as THF) and ethylene-oxa Lee de irregularly Arranged so-called random copolymers are used.
[0018]
In the present invention, when a block copolymer is used, the resulting polyurethane elastic fiber has a remarkable water absorption, so that there is a problem that the physical properties during water absorption are lowered.
[0019]
That is, the polyol used in the present invention can also be expressed as poly (tetramethylene-co-ethylene ether) glycol.
[0020]
In such poly (tetramethylene-co-ethylene ether) glycol, the ethylene ether is preferably contained in an amount of 15 to 37 mol%, more preferably 20 to 35 mol%, based on the total alkylene ether.
[0022]
Furthermore, the polyol used in the present invention may be composed only of a random copolymer, may be copolymerized with another polyol, and is further mixed with another polyol. Also good.
[0023]
As other polyols, poly (1,4-tetramethylene glycol) (hereinafter abbreviated as PTMG) from the viewpoint of obtaining a product having excellent cold resistance, high extensibility, and high recoverability. , Po Li caprolactone diol, to use polyethylene ether glycol or the like. Such other polyols may be one kind or two or more kinds.
[0024]
In the present invention, preferably the molar fraction of ethylene-oxa Lee de Unit is in a range of 5% to 90% [0025]
The weight average molecular weight of the polyol used in the present invention is preferably in the range of 1000 or more and 6000 or less from the viewpoints of elongation, strength, heat resistance and the like when formed into a yarn.
[0026]
More preferably, it is the range of 1300-4500. By using a polyol having a molecular weight within this range, an elastic yarn having a balanced mechanical property can be obtained.
[0027]
Next, the diisocyanate used in the present invention is, for example, 5-isocyanate-1- (isocyanatemethyl) -1,3,3-trimethylcyclohexane, 1-isocyanate-4-[(4-isocyanatophenyl) methyl] benzene, 1- Isocyanate-2-[(4-isocyanate-phenyl) methyl] benzene, 1,1′-methylenebis (4-isocyanatecyclohexane), 4-methyl-1,3-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate (hereinafter, Aromatic diisocyanates such as 2,4-tolylene diisocyanate (hereinafter abbreviated as TDI), 1,4-diisocyanate benzene, xylylene diisocyanate, 2,6-naphthalene diisocyanate, Strong It preferred have for the synthesis of polyurethane.
[0028]
Further, as the alicyclic diisocyanate, for example, methylene bis (cyclohexyl isocyanate) (hereinafter abbreviated as H ₁₂ MDI), isophorone diisocyanate, methylcyclohexane 2,4-diisocyanate, methylcyclohexane 2,6-diisocyanate, cyclohexane 1,4-diisocyanate , Hexahydroxylylene diisocyanate, hexahydrotolylene diisocyanate, octahydro 1,5-naphthalene diisocyanate and the like are preferable. Aliphatic diisocyanates are preferably used particularly when yellowing of the polyurethane yarn is suppressed.
[0029]
And these diisocyanates may be used independently and may be used in combination of 2 or more types.
[0030]
The ratio of the molar amount of the diisocyanate is preferably in the range of 1.2 to 2.3 with respect to the polyol 1 from the viewpoint of strength characteristics of the resulting polyurethane elastic fiber.
[0031]
Next, a low molecular diol is used as the chain extender used in the present invention.
[0032]
The low molecular weight diol, preferably used ethylene glycol.
[0033]
In particular, high heat resistance as polyurethane diol extended, also from the viewpoint of obtaining a high elastic polyurethane fiber strength, it is preferable to use ethylene glycol.
[0034]
The polyurethane elastic fiber of the present invention includes hindered phenols such as UV absorbers, antioxidants, and gas-resistant stabilizers, such as so-called BHT and “Smizer” GA-80 manufactured by Sumitomo Chemical Co., Ltd. Drugs, various benzotriazole drugs such as "Tinuvin", phosphoric drugs such as "Sumilyzer" P-16 manufactured by Sumitomo Chemical Co., Ltd., and hindered amine drugs including various "Tinuvin" In addition, inorganic pigments such as titanium oxide, zinc oxide and carbon black, metal soaps such as magnesium stearate, and bactericides, deodorants, silicones and minerals containing silver, zinc and their compounds Various antistatic agents including lubricants such as oil, barium sulfate, cerium oxide, betaine and phosphates Etc. or contains, also to have reacted with the polymer are also preferred.
[0035]
And in order to further improve the durability to light and various nitric oxides in particular, a nitric oxide scavenger such as HN-150 manufactured by Nippon Hydrazine Co., Ltd., a thermal oxidation stabilizer such as manufactured by Sumitomo Chemical Co., Ltd. It is preferable to use “Sumilyzer” GA-80 and a light stabilizer such as “Sumisorb” 300 # 622 manufactured by Sumitomo Chemical Co., Ltd.
[0036]
The fineness and cross-sectional shape of the polyurethane elastic fiber of the present invention are not particularly limited. For example, the cross section may be circular or flat.
[0037]
In the polyurethane elastic fiber of the present invention, the residual strain at −5 ° C. is preferably 90% or less, more preferably 50% or less, and further preferably 26% or less.
[0038]
Next, the manufacturing method of the polyurethane elastic fiber of this invention is demonstrated in detail.
[0039]
In the present invention, it is preferable to prepare a polyurethane solution first.
[0040]
In the present invention, any method may be used for producing a polyurethane which is a solute of a polyurethane solution and for producing a polyurethane solution.
[0041]
That is, either a melt polymerization method or a solution polymerization method may be used. However, the solution polymerization method is more preferable. In the case of the solution polymerization method, the generation of foreign matters such as gel is small in the polyurethane. Of course, solution polymerization is preferable from the viewpoint of production efficiency because it saves labor to make a solution.
[0042]
And in the present invention is the use of a polyurethane polyol is a random copolymer of tetrahydrofuran and ethylene oxa Lee de, a diisocyanate and ethylene glycol as a main component.
[0043]
The weight average molecular weight of particular polyols among these is in the range of 1000 to 6000 or less, a diol which is a chain extender is ethylene glycol, diisocyanate polyurethane synthesized in solution MDI as the main raw material is preferred.
[0044]
Such polyurethane can be obtained, for example, by synthesis using DMAC, DMF, DMSO, NMP, or the like, or a solvent containing these as a main component, using the above raw materials.
[0045]
For example, each raw material is charged in such a solvent, dissolved, heated to an appropriate temperature and reacted to form polyurethane, a so-called one-shot method, or a polyol and MDI are first melt-reacted, and then the reactants are added. A particularly preferable method is a method of dissolving in a solvent and reacting with the diol to form polyurethane.
[0046]
In addition, when synthesizing such polyurethane, it does not matter at all if one or two or more amine catalysts or organometallic catalysts are mixed. Typical examples of these are amine catalysts such as N, N-dimethylcyclohexylamine, N, N-dimethylbenzylamine, triethylamine, N-methylmorpholine, N-ethylmorpholine, N, N, N. ', N'-tetramethylethylenediamine, N, N, N', N'-tetramethyl-1,3-propanediamine, N, N, N ', N'-tetramethylhexanediamine, bis-2-dimethylamino Ethyl ether, N, N, N ′, N ′, N′-pentamethyldiethylenetriamine, tetramethylguanidine, triethylenediamine, N, N′-dimethylpiperazine, N-methyl-N′-dimethylaminoethyl-piperazine, N— (2-dimethylaminoethyl) morpholine, 1-methylimidazole, 1,2-dimethylimidazole, N N-dimethylaminoethanol, N, N, N′-trimethylaminoethylethanolamine, N-methyl-N ′-(2-hydroxyethyl) piperazine, 2,4,6-tris (dimethylaminomethyl) phenol, N, N-dimethylaminohexanol, triethanolamine and the like can be preferably used. As the organometallic catalyst, tin octoate, dibutyltin dilaurate, lead dibutyl octoate and the like can be preferably used.
[0047]
Furthermore, in the present invention, it is also preferable to use a chain terminator in order to control the molecular weight of the polyurethane and the viscosity of the polyurethane spinning solution.
[0048]
As such a chain terminator, n-butanol, diethylamine, cyclohexylamine, n-hexylamine and the like are preferable.
[0049]
In general, the chain terminator is preferably used as a mixture with a chain extender.
[0050]
Small amounts of trifunctional materials such as diethylenetriamine and glycerol can also be used to control polymer viscosity.
[0051]
The concentration of the polyurethane solution thus obtained is not particularly limited, but it is usually preferably in the range of 30% by weight to 80% by weight.
[0052]
In the present invention, it is preferable to add the various additives described above to the polyurethane solution. Any method can be adopted as a method for adding the additive to the polyurethane solution. As a typical method, a method using a static mixer, a method using stirring, or the like can be used.
[0053]
Here, the additive is preferably added as a solution. When it is a solution, it can be uniformly added to the polyurethane solution.
[0054]
In the present invention, a polyurethane elastic fiber is obtained by spinning a polyurethane solution.
As the spinning method, any of a wet method, a dry method, and a melting method may be used.
[0055]
From the viewpoint of increasing the spinning speed, spinning by a dry method is preferred. In dry spinning, when a fiber is formed by discharging a polyurethane solution from a nozzle to a spinning cylinder provided with at least two gas supply units and a gas suction unit provided between the gas supply units, The temperature of the gas supplied from the gas supply unit provided at the lower part of the spinning cylinder is preferably 60 ° C. or less from the viewpoint of eliminating yarn unevenness.
[0056]
In spinning, the speed ratio between the godet roller and the winder is preferably determined according to the purpose of use of the yarn.
[0057]
In this invention, it is preferable to wind up by setting the speed ratio of a godet roller and a winder as 1.1 or more and 1.8 or less.
[0058]
The spinning speed is preferably from 300 m / min to 800 m / min.
[0059]
【Example】
The invention is explained in more detail by means of examples. However, the present invention is not limited to these examples.
[0060]
A method for quantifying stress relaxation, strength, elongation, residual strain, and heat setability in the present invention will be described.
[Stress relaxation, strength, elongation, residual strain]
Stress relaxation, strength, elongation, and residual strain were obtained by tensile testing polyurethane yarn using an Instron 4502 type tensile tester.
[0061]
The stress relaxation, strength, and elongation were measured at 22 ° C., and the residual strain was measured at −5 ° C.
[0062]
These are defined by:
[0063]
300% elongation of a 5 cm (L1) sample was repeated 5 times at a tensile speed of 50 cm / min. The stress at this time was defined as (G1).
[0064]
The length was then held for 30 seconds. The stress after holding for 30 seconds was defined as (G2).
[0065]
The sample length when the stress was 0 was (L2).
[0066]
Furthermore, it extended | stretched until the polyurethane yarn cut | disconnected 6th time.
[0067]
The stress at the time of rupture was defined as (G3), and the sample length at the time of rupture was defined as (L3).
[0068]
Hereinafter, the characteristics were obtained by the following formula.
[0069]
Strength = (G3)
Stress relaxation (%) = 100 × ((G1) − (G2)) / (G1)
Residual strain (%) = 100 × ((L2) − (L1)) / (L1)
Elongation (%) = 100 × ((L3) − (L1)) / (L1)
[Heat set property]
The yarn was free treated with 100 ° C. steam for 10 minutes, then free treated with 100 ° C. boiling water for 2 hours and dried at room temperature for one day. Next, the yarn (length = (L4)) was elongated 100% (length = 2 × (L4)). The length was treated with 115 ° C. steam for 1 minute. Furthermore, it was dry heat-treated at 130 ° C. with the same length, and further allowed to stand at room temperature for 1 day with the same length.
[0070]
Next, the stretched state of the yarn was removed, and the length (L5) was measured.
[0071]
Heat setting property (%) = 100 × ((L5) − (L4)) / (L4)
[Example 1]
A dimethylacetamide solution of polyurethane (40), a polyol (“Tetraxinol” manufactured by Sanyo Chemical Industries Co., Ltd.), MDI and ethylene glycol, which is a random copolymer having a ratio of THF / ethylene oxide of 70/30 and a molecular weight of 3300 % By weight) was used as a sample solution. The obtained solution was discharged into nitrogen gas having a dry atmosphere temperature of 380 ° C., and dry spinning was performed at a speed ratio of 540 m / min with a speed ratio of the godet roller and the winder of 1.42, whereby 20 decitex monofilament yarn Got. Spinnability was good.
[0072]
Table 1 shows the elongation, strength, stress relaxation, heat setability, and residual strain measured at -5 ° C.
[0073]
A product having excellent elastic properties without stickiness even at low temperatures and having excellent extensibility and recoverability was obtained.
[0074]
[ Reference Example 1 ]
A sample solution was a dimethylacetamide solution (38% by weight) of polyurethane consisting of polyol, MDI and ethylene glycol, which is a random copolymer having a ratio of THF to propylene oxide of 70/30 and a molecular weight of 3000. The obtained solution was discharged into nitrogen gas having a dry atmosphere temperature of 380 ° C., and dry spinning was performed at a speed ratio of 540 m / min with a speed ratio of the godet roller and the winder of 1.42, whereby 20 decitex monofilament yarn Got. Spinnability was good.
[0075]
Table 1 shows the elongation, strength, stress relaxation, heat setability, and residual strain measured at -5 ° C.
[0076]
A product having excellent elastic properties without stickiness even at low temperatures and having excellent extensibility and recoverability was obtained.
[0077]
[Example 2 ]
Polyurethane dimethylacetamide solution (38), which is a random copolymer having a ratio of THF to ethylene oxide of 90/10 and a molecular weight of 3,300 (“Tetraxinol” manufactured by Sanyo Chemical Industries, Ltd.), MDI and ethylene glycol. % By weight) was used as a sample solution. The obtained solution was discharged into nitrogen gas having a dry atmosphere temperature of 380 ° C., and dry spinning was performed at a speed ratio of 540 m / min with a speed ratio of the godet roller and the winder of 1.42, whereby 20 decitex monofilament yarn Got. Spinnability was good.
[0078]
Table 1 shows the elongation, strength, stress relaxation, heat setability, and residual strain measured at -5 ° C.
[0079]
A product having excellent elastic properties without stickiness even at low temperatures and having excellent extensibility and recoverability was obtained.
[0080]
[Example 3 ]
According to the method described in JP-A-1-98624, 811 parts (11.26 mol) of THF and 25 g (0.28 mol) of 1,4-butanediol were charged into a pressure reactor, and BF ₃ -THF In the presence of 6.6 g of the complex and 0.8 g of water, 154.2 g of ethylene oxide was reacted. Filtration etc. were performed by the method of the said gazette, and the obtained polyol was 620g. The addition rate of THF was 54%.
[0081]
The obtained polyol had a ratio of THF / ethylene oxide of 70/30, a weight average molecular weight of 3,300, and a number average molecular weight of 2,100.
[0082]
Polyol and MDI are reacted so that the molar ratio (capping ratio) of diisocyanate is 1.64 with respect to polyol to form capped (isocyanate-terminated) glycol and dissolved in DMAc, and ethylene as a chain extender. A sample solution (40% by weight) was formed using glycol and n-butanol as the chain terminator. As an additive, E.I. I. DuPont de Nemours and Company “Methacryl® 2462B” (2.2 wt%) and E.I. I. “Methacryl® 2390D” (0.9 wt%) from duPont de Nemours and Company was added to the sample solution.
[0083]
The sample solution is discharged into a nitrogen gas having a dry atmosphere temperature of 380 ° C., and dry spinning is performed at a speed of 540 m / min with a speed ratio of a godet roller and a winder of 1.42, whereby a 20 dtex 2-filament yarn is obtained. Obtained. Spinnability was good.
[0084]
The elongation of the yarn was 460%, the strength was 0.9 cN / dtex, the stress relaxation was 18%, the heat setting property was 78%, and the residual strain measured at -5 ° C was 20%.
[0085]
A product having excellent elastic properties without stickiness even at low temperatures and having excellent extensibility and recoverability was obtained.
[0086]
[ Reference Example 2 ]
A polyol was prepared in the same manner as described in Example 3 except that propylene oxide was used instead of ethylene oxide.
[0087]
The obtained polyol had a ratio of THF / propylene oxide of 70/30, a weight average molecular weight of 3000, and a number average molecular weight of 1900.
[0088]
Reaction of polyol and MDI (capping ratio 1.64) to form capped (isocyanate-terminated) glycol and dissolve in DMAc, sample solution using ethylene glycol as chain extender and n-butanol as chain terminator (38% by weight) was formed. The same additive as in Example 3 was used.
[0089]
The sample solution is discharged into a nitrogen gas having a dry atmosphere temperature of 380 ° C., and dry spinning is performed at a speed of 540 m / min with a speed ratio of a godet roller and a winder of 1.42, whereby a 20 dtex 2-filament yarn is obtained. Obtained. Spinnability was good.
[0090]
The elongation of the yarn was 480%, the strength was 1.0 cN / dtex, the stress relaxation was 20%, the heat setting property was 79%, and the residual strain measured at −5 ° C. was 23%.
[0091]
A product having excellent elastic properties without stickiness even at low temperatures and having excellent extensibility and recoverability was obtained.
[0092]
[Comparative Example 1]
By dry-spinning a polyurethane dimethylacetamide solution (39% by weight) consisting of PTMG, MDI and ethylene glycol having a molecular weight of 2100 at a speed ratio of 1.40 and a godet roller to a winder of 540 m / min, 20 decitex A monofilament yarn was obtained. Table 1 shows the elongation, strength, stress relaxation, heat setability, and residual strain measured at -5 ° C.
[0093]
[Table 1]

[0094]
【The invention's effect】
According to the present invention, a polyurethane elastic fiber having an excellent low-temperature characteristic without losing elasticity even at low temperatures and having good extensibility and recoverability, and also having good heat setting properties. Obtainable. When the polyurethane elastic fiber of the present invention is used for clothes or the like, it is possible to obtain a product excellent in fit, appearance quality, wearability, wear feeling and the like. Because of having these excellent characteristics, not only by itself, but also in combination with various fibers, for example, socks, stockings, circular knitting, tricot, swimsuit, ski pants, work clothes, smoke fire clothes, clothes, golf pants, Tightening materials for various textile products such as wet suits, bras, girdles, gloves and socks, fastening materials for preventing sanitary products such as paper diapers, fastening materials for waterproofing materials, imitation baits, artificial flowers, electrical insulation materials, wiping cloths It can be used for various applications such as copy cleaners and gaskets.

Claims (6)

A polyurethane which is the main constituent is a polyol, a diisocyanate and ethylene glycol, polyurethane elastic fiber characterized in that the polyol is a random copolymer of tetrahydrofuran and ethylene-oxa i de. The polyurethane elastic fiber according to claim 1, the mole fraction of ethylene-oxa Lee de Unit is characterized in that in the range of 5% to 90%. The polyurethane elastic fiber according to claim 1 or 2, wherein the molecular weight of the polyol is in the range of 1000 to 6000. The polyurethane elastic fiber according to any one of claims 1 to 3, wherein a residual strain at -5 ° C is 90% or less. Random copolymer and a polyol, producing a polyurethane elastic fiber characterized in that the polyurethane as a main constituent diisocyanate and ethylene glycol spinning a polyurethane solution as a solute of tetrahydrofuran and ethylene-oxa i de. 6. The method for producing a polyurethane elastic fiber according to claim 5, wherein the spinning method is dry.