JPH10226921A - Polyurethane fiber and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain polyurethane fiber that is composed of a polyurethane having a specific chemical structure, high resistance to light, yellowing, abrasion and mildew and is rich in stretchability. SOLUTION: This fiber comprises a polyurethane represented by the formula (R1 is a modified polycarbonate diol residue composed of a polycarbonate diol of 1,6-hexanediol and other diol; R2 is an alicyclic diisocyanate residue; R3 is a diamine residue). For example, a modified polycarbonate diol containing a polycarbonate diol of 1,6-hexanediol and other diols at a weight ratio of 95/5-65/35 is allowed to react with an alicyclic diisocyanate, for example, methylenebis(cyclohexyldiisocyanate) in the absence of solvent, then the resultant polyurethane copolymer is dissolved in dimethyl formamide or acetamide. Then, ethylenediamine is added to the solution and they are allowed to react with each other at room temperature to 60 deg.C and the polyurethane solution is subjected to dry-spinning to produce the objective polyurethane fiber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soft stretchable polyurethane fiber having excellent durability and a method for producing the same.

More specifically, it has high light resistance and high yellowing resistance, and also has excellent mechanical durability such as abrasion resistance, excellent shape fixation, and has sufficient resistance to mold and the like. In addition, the present invention relates to a soft stretchable polyurethane fiber and a method for producing the same.

[0003]

2. Description of the Related Art At present, high molecular weight diols are used as polyurethane diols, for example, as disclosed in JP-A-57-100778, JP-A-57-100779 and JP-A-5-05.
As disclosed in JP-A-1428 and JP-A-5-032754, mainly polyester diols,
Polyether diols and polycarbonate diols are disclosed. On the other hand, aromatic diisocyanates, particularly 4,4'-diphenylmethane diisocyanate (hereinafter, referred to as MDI) are mainly used as diisocyanate compounds because of their high reactivity with active hydrogen. In addition, a low molecular weight diamine or a low molecular weight diol is used as a chain extender.

[0004] There are three spinning methods: dry, wet, and melt. From the viewpoint of productivity and the like, the spinning is mainly performed by a dry or melt spinning method capable of spinning at a high winding speed. I have.

[0005]

However, for example, for example, "Latest Polyurethane Application Technology" supervised by Keiji Iwata, CMC (198
According to reviews such as 5), polyurethane fibers using polyester diol are inferior in hydrolysis resistance and mold resistance. Polyurethane fibers using polyether diol are said to improve hydrolysis resistance and mold resistance, but are inferior in light resistance and heat resistance. Further, polyurethane fibers using polycarbonate diol are said to have low flexibility and low elongation because polycarbonate diol is crystalline. On the other hand, polyurethane fibers using MDI are inferior in light resistance and yellowing resistance due to nitrogen oxides. An object of the present invention is to improve the disadvantages of the prior art and to provide a polyurethane fiber having excellent durability and soft stretchability.

[0006]

The present invention adopts the following means in order to solve the above-mentioned problems. That is, the present invention relates to a polyurethane fiber comprising a polyurethane having a chemical structure represented by the following formula (I) and a method for producing the same.

[0007]

Embedded image Here, R1 is a polycarbonate diol residue of 1,6-hexanediol, or a modified polycarbonate diol residue of 1,6-hexanediol and another diol, R2 is an alicyclic diisocyanate residue, R3 represents a diamine residue.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The polymer diol used in the present invention is a polycarbonate diol obtained by subjecting 1,6-hexanediol to a transesterification reaction with a dialkyl carbonate, or a polycarbonate diol comprising 1,6-hexanediol and another diol. Although it is a modified polycarbonate diol obtained by copolymerizing a diol, it is preferable to use a modified polycarbonate diol. By using the modified polycarbonate diol, a polyurethane fiber having a high elongation can be obtained.
Examples of the diol to be mixed with the polycarbonate diol composed of 1,6-hexanediol include 1,3-propanediol, 2-methyl-1,4-butanediol, neopentyl glycol, 1,5-pentanediol, cyclohexanediol, Examples include polytetramethylene ether glycol, polycaprolactone diol, and the like. The copolymerization ratio is preferably from 95: 5 to 65:35 by weight, more preferably from 90:10 to 70:30, in view of the elongation and spinnability of the yarn. The number average molecular weight of the modified polycarbonate diol is preferably from 1,000 to 8,000 for the same reason, and is preferably from 1,000 to 8,000.
More preferably, it is 5000. Further, when the number average molecular weight is set to 1500 to 3000, the strength and elongation of the yarn can be made equal to or higher than those of the conventional yarn, and it is particularly preferable.

From the viewpoint of the melting point and elongation of the yarn, the molar ratio of the modified polycarbonate diol to the alicyclic diisocyanate is 1:
It is preferably in the range of 1.3 to 1: 3.0. Particularly preferred molar ratios are in the range of 1: 1.5 to 1: 2.2. Within this range, a polyurethane fiber having a high elongation and a high melting point is obtained.

The diisocyanate compound used in the present invention is an alicyclic diisocyanate. As the alicyclic diisocyanate to be used, for example, methylene bis (cyclohexyl isocyanate) (hereinafter referred to as H12MDI), isophorone diisocyanate, methylcyclohexane-
2,4-diisocyanate, methylcyclohexane-
2,6-diisocyanate, cyclohexane-1,4-
Examples include diisocyanate, hexahydroxylylene diisocyanate, hexahydrotolylene diisocyanate, octahydro-1,5-naphthalenediisocyanate, and the like. One or more of these diisocyanate compounds can be selected and used. Among them, H12MDI is particularly preferred. H12MD
Although the cause is unknown when I is used, the stress in the low elongation region is low and the fiber has high elongation. The chain extender used in the present invention is a low molecular weight diamine. Use of a low molecular weight diol is not preferred because it causes problems such as a decrease in the melting point of the yarn and a long reaction time. In addition, you may use together a low molecular weight diol in the range which does not prevent the effect of this invention. Examples of the low molecular weight diamine include ethylene diamine, 1,2-propane diamine, 1,3-propane diamine, hexamethylene diamine, 1,4-cyclohexyl diamine, and 1,3-cyclohexyl diamine. One or two or more of these can be selected and used. The polyurethane fiber has excellent elongation and elastic recovery, and the polyurethane solution before spinning has excellent stability. It is particularly preferable to use ethylene diamine. The polyurethane fiber of the present invention preferably has a molecular weight of 40,000 to 150,000. Within this range, the fiber will have high durability and strength. In addition, the molecular weight in this invention is measured by GPC, and is converted by polystyrene.

The melting point of the polyurethane fiber on the high temperature side is from 200 ° C. to 2 ° C. because of its excellent shape fixability and heat resistance during processing.
Preferably it is 50 ° C. In addition, the melting point in the present invention is a value of the second run measured by DSC after the fiber is finely cut.

The stress when the polyurethane fiber is stretched by 100% is preferably about 0.020 to 0.070 times the breaking strength. More preferably, 0.020 to 0.04
It is 0 times. The stress at the time of elongation by 200% is preferably about 0.035 to 0.150 times the breaking strength. More preferably, it is 0.035 to 0.070 times.

[0013] By doing so, the fiber has a smooth stretch property and a moderate wiping force.

The fineness and cross-sectional shape of the fiber of the present invention are not particularly limited. For example, the cross section of the yarn may be circular or flat. Further, the fiber of the present invention has no problem even if it contains various stabilizers and pigments. For example, hindered phenolic drugs such as so-called BHT and Sumitomo GA-80 manufactured by Sumitomo Chemical, benzotriazole-based drugs including various tinuvins, Sumitomo Chemical Sumitomo P- Phosphorus drugs including 16
Various types of hindered amines including tinuvin, inorganic pigments including titanium oxide, zinc oxide and carbon black, metal soaps including magnesium stearate, and sterilization including silver, zinc and their compounds Agents, deodorants, lubricants such as silicone and mineral oil, barium sulfate, cerium oxide, various antistatic agents such as betaine and phosphoric acid, etc. I don't care.

In order to further increase the durability especially against light and various types of nitric oxide, a nitric oxide supplement such as HN-150 manufactured by Nippon Hydrazine, a thermal oxidation stabilizer such as Sumilizer GA- manufactured by Sumitomo Chemical Co., Ltd. 80, it is effective to use a light stabilizer such as Sumizob 300 # 622 manufactured by Sumitomo Chemical.

The method of addition is not particularly limited, and a conventionally known method such as a static mixer method can be applied.

Next, the method for producing polyurethane in the present invention will be described in detail. The polyurethane in the present invention uses ethylenediamine as a chain extender and has a significantly different reactivity to a diisocyanate compound than a modified polycarbonate diol. A terminal urethane prepolymer is synthesized, a solvent inert to isocyanate groups and a chain extender diluted with the solvent are added to the prepolymer, and the mixture is further reacted at room temperature to 60 ° C. to obtain a high molecular weight thermoplastic polyurethane. It is particularly preferred to produce by the prepolymer method for obtaining

Examples of the solvent inert to the isocyanate group include dimethylformamide, dimethylacetamide, dimethylsulfoxide, methylethylketone, toluene, xylene, dioxane, tetrahydrofuran, ethyl acetate, N-methylpyrrolidone and the like. One or more of these solvents can be used, but it is preferable to use an amide-based solvent such as dimethylformamide or dimethylacetamide which can increase the solvent concentration.

For the purpose of adjusting to a desired molecular weight or viscosity, for example, diethylamine, butylamine,
Ethanol, propanol, butanol and the like may be used as a reaction terminator. Particularly preferred are secondary monoamines such as diethylamine.
For some reason, a highly durable yarn can be obtained by using a secondary monoamine.

The melt concentration is preferably from 30% to 40% from the viewpoint of spinnability during spinning and polymer viscosity. Also,
The polymer viscosity ranges from 1200 poise to 65 due to spinnability during spinning and gel formation in the high temperature region of the spinning machine header.
It is preferably set to 00 poise, more preferably 2000 poise to 6000 poise. The melting point on the high temperature side of the polymer is 200 because of its excellent shape fixability and heat resistance when formed into fibers.
It is preferably from 250C to 250C. The melting point in the present invention is a value of a second run measured by DSC after a film of the polyurethane solution is prepared using an applicator having a thickness of 12 μm, the solvent is dried under a nitrogen atmosphere. Further, the molecular weight of the polymer is preferably from 40,000 to 150,000, since durability and strength when formed into fibers are increased. In addition, the molecular weight in this invention is measured by GPC, and is converted by polystyrene.

The spinning can be carried out by using either a wet spinning method or a dry spinning method, but it is preferable to perform the spinning by a dry spinning method capable of increasing the spinning speed.

During spinning, the speed ratio between the godet roller and the winder is between 1.30 and 1.65, which allows the elongation and strength of the yarn to be equal to or higher than that of a conventional yarn. Is preferred.

[0023]

EXAMPLES The present invention will be described in more detail with reference to Examples. However, the present invention is not limited by these examples. The evaluation method used in the present invention is described below.

1. Measurement of Elongation at Break and Strength Using an Instron 4502 type tensile tester, a sample having a length of 5 cm was subjected to 300 times at a tensile speed of 50 cm / min five times.
% Elongation, then elongate until the sixth break,
The elongation at break and the strength were measured. The stress at the time of 100% elongation and the stress at the time of 200% elongation in the present invention are the same at the time of 100% elongation in the first tensile test.
This is the stress at the time of elongation by 200%. The elongation at break and strength are 6
The elongation and strength at the time of the second break.

2. Measurement of Durability After irradiation with a sunshine weather meter for 15 hours at 63 ° C. and 60% RH, the breaking elongation and the strength were measured.

3. Measurement of yellowing resistance Using a Scott tester, NO2 gas 7 ppm, 40
The yarn was irradiated with an ultraviolet lamp under the conditions of 60 ° C. and 60% RH, and the yellowing degree (Δb value) of the yarn after 50 hours was measured using a color master.

Example 1 A modified polycarbonate diol obtained by copolymerizing a mixture of a polycarbonate diol composed of 1,6-hexanediol and poly-ε-caprolactone diol at a weight ratio of 9: 1 was used. NCO-terminated urethane prepolymer (manufactured by Sanyo Chemical Co., Ltd., produced by reacting 4,4'-methylenebis (cyclohexyl isocyanate) at a molar ratio of 1: 1.8.
% = 2.69%) in 21 separable flasks.
After taking 2 g and dissolving in 1094 g of DMAc, 10.
A solution obtained by diluting a mixed solution of 62 g of ethylenediamine and 0.52 g of diethylamine with 100.2 g of DMAc was dropped over 20 minutes to perform a chain extension reaction,
A viscous polymer solution was obtained. HN- as an additive used
1.7 (manufactured by Nippon Hydrazine) 1.7% by weight, GA-8
0 (Sumitomo Chemical) 0.9% by weight, Sumizob 300 # 6
22 was used in an amount of 0.4% by weight. (The same additives were used in the same content in the following examples.) The viscosity of the polymer solution was measured by a falling ball viscometer and was measured at 40 ° C. at 35 ° C.
It was 40 poise. Next, polymer solution (solid content 32%)
Was dry-spun at a speed of 530 m / min with a speed ratio of a godet roller and a winder of 1.45, and a 18 denier / monofilament yarn was wound around a normal cardboard tube. Stress at 100% elongation of this yarn, stress at 200% elongation, elongation at break, strength, (stress at 100% elongation) / (breaking strength),
Table 1 shows the results of (stress at 200% elongation) / (rupture strength), durability and yellowing resistance.

(Example 2) A modified polycarbonate diol obtained by copolymerizing a mixture of a polycarbonate diol composed of 1,6-hexanediol and poly-ε-caprolactone diol at a weight ratio of 9: 1 was used. NCO-terminated urethane prepolymer (manufactured by Sanyo Chemical Co., Ltd., NCO) prepared by reacting 4,4'-methylenebis (cyclohexyl isocyanate) at a molar ratio of 1: 1.9.
% = 3.03%) into 55 separate separable flasks.
After taking 0 g and dissolving in 1080 g of DMAc, 11.
A chain elongation reaction was carried out by dropping a solution obtained by diluting a mixed solution of 92 g of ethylenediamine and 0.58 g of diethylamine with 112.5 g of DMAc over 20 minutes,
A viscous polymer solution was obtained.

The viscosity of this polymer solution was measured with a falling ball viscometer and was 1986 poise at 40 ° C. Next, the polymer solution (solid content: 32%) was dry-spun at a speed of 530 m / min with the speed ratio of the godet roller and the winder set to 1.45.
The 8 denier / monofilament yarn was wound onto a conventional cardboard tube. Stress at 100% elongation of this yarn, stress at 200% elongation, elongation at break, strength, (stress at 100% elongation) / (breaking strength), (stress at 200% elongation) / (breaking strength) , Durability and yellowing resistance are shown in Table 1.

Example 3 A modified polycarbonate diol obtained by copolymerizing a mixture of a polycarbonate diol composed of 1,6-hexanediol and poly-ε-caprolactone diol at a weight ratio of 9: 1 was used. An NCO-terminated urethane prepolymer (manufactured by Sanyo Chemical Co., Ltd.) obtained by reacting a mixture of 4,4'-methylenebis (cyclohexyl isocyanate) and isophorone diisocyanate at a weight ratio of 9: 1 at a molar ratio of 1: 1.8. NCO% = 2.68%) was taken in a separable flask (21) in an amount of 536.9 g, dissolved in 1067 g of DMAc, and dissolved in 10.30 g of ethylenediamine and 0.53 g of DMAc.
A mixture of 0 g of diethylamine was mixed with 97.2 g of DMAc.
Was added dropwise over 20 minutes to carry out a chain elongation reaction to obtain a viscous polymer solution. The viscosity of this polymer solution was measured with a falling ball viscometer,
Poise. Next, the polymer solution (solid content 32%)
The speed ratio between the godet roller and the winder is 1.45, and the speed ratio is 5
Dry spinning was performed at a speed of 30 m, and the 18 denier / monofilament yarn was wound around a conventional cardboard tube. 10 of this thread
Stress at 0% elongation, stress at 200% elongation, elongation at break,
Strength, (stress at 100% elongation) / (rupture strength), (2
Table 1 shows the results of stress at 00% elongation) / (rupture strength), durability and yellowing resistance.

Example 4 A modified polycarbonate diol obtained by copolymerizing a mixture of a polycarbonate diol composed of 1,6-hexanediol and poly-ε-caprolactone diol at a weight ratio of 9: 1 was used. An NCO-terminated urethane prepolymer (manufactured by Sanyo Chemical Co., Ltd.) obtained by reacting a mixture of 4,4'-methylenebis (cyclohexyl isocyanate) and isophorone diisocyanate at a weight ratio of 9: 1 at a molar ratio of 1: 1.9. NCO% = 2.96%) was placed in a separable flask (21, 534.9 g), dissolved in 1051 g of DMAc, and dissolved in 11.33 g of ethylenediamine and 0.53 g of DMAc.
A mixture of 5 g of diethylamine was mixed with 106.9 g of DMA.
By dropping the solution diluted in c over 20 minutes,
A chain extension reaction was performed to obtain a viscous polymer solution. The viscosity of this polymer solution was measured with a falling ball viscometer,
It was 6 poise. Next, polymer solution (solid content 32%)
Was spin-dried at a speed of 530 m / min with a speed ratio of a godet roller and a winder of 1.45, and an 18 denier / monofilament yarn was wound up on a normal cardboard tube. Stress at 100% elongation of this yarn, stress at 200% elongation, elongation at break, strength, (stress at 100% elongation) / (breaking strength),
Table 1 shows the results of (stress at 200% elongation) / (rupture strength), durability and yellowing resistance.

(Comparative Example 1) An NCO-terminated urethane prepolymer was obtained by reacting polytetramethylene glycol having a molecular weight of 1800 with MDI at a temperature of 90 ° C and no solvent at a molar ratio of 1: 1.58 for 2 hours. Was. The NCO% was 2.22%. After cooling this prepolymer to room temperature, 500 g was put into a separable flask of 21 and 100
After dissolving in 0 g of DMAc, a mixed solution of 7.80 g of ethylenediamine and 1.17 g of diethylamine was added.
By adding a solution diluted with 7 g of DMAc, a chain extension reaction was performed to obtain a viscous polymer solution. The viscosity of this polymer solution was measured with a falling ball viscometer,
Poise. Next, the polymer solution (solid content 32%)
Dry spinning was performed at a speed of 733 m / min, and a yarn of 20 denier / 2 filaments was wound around a normal cardboard tube. Stress at 100% elongation of this yarn, stress at 200% elongation, elongation at break, strength, (stress at 100% elongation) / (breaking strength),
Table 1 shows the results of (stress at 200% elongation) / (rupture strength), durability and yellowing resistance together with examples.

[0033]

[Table 1]

[0034]

According to the present invention, the durability of the polyurethane fiber obtained according to the present invention is remarkably improved as compared with the conventional polyurethane fiber. Moreover, the elongation is almost the same as that of the conventional polyurethane fiber. Because of these excellent properties, in addition to being used alone, in combination with various fibers, for example, socks, stockings, circular knits, tricots, swimwear, ski pants, work clothes, smoke suits, clothes, golf pants, Tightening materials for various textiles including wet suits, bras, girdles, gloves and socks,
Tightening material for preventing leakage of sanitary products such as paper diapers,
Tightening materials for waterproof materials, fake bait, artificial flowers, electrical insulation,
It can be applied to various uses such as wiping cloth, copy cleaner, gasket, etc.

Claims (8)

[Claims] 1. A polyurethane fiber comprising a polyurethane having a chemical structure represented by the following formula (I). Embedded image Here, R1 is a polycarbonate diol residue of 1,6-hexanediol, or a modified polycarbonate diol residue of 1,6-hexanediol and another diol, R2 is an alicyclic diisocyanate residue, R3 represents a diamine residue. 2. The polyurethane fiber according to claim 1, wherein the copolymerization ratio of the polycarbonate diol comprising 1,6-hexanediol to another diol is 95: 5 to 65:35 by weight. 3. The polyurethane fiber according to claim 1, wherein a mixing ratio of the polymer diol and the alicyclic diisocyanate compound is from 1: 1.3 to 1: 3.0 in molar ratio. 4. The method according to claim 1, wherein the other diol is poly-ε-caprolactone diol, at least the alicyclic diisocyanate compound is methylene bis (cyclohexyl diisocyanate), and at least the chain extender is ethylene diamine. 4. The polyurethane fiber according to 3. 5. The polyurethane fiber according to claim 1, wherein the high-temperature side has a melting point of 200 ° C. to 250 ° C. and a number average molecular weight of 40,000 to 150,000. 6. (Stress at 100% elongation) / (rupture strength) = 0.020 to 0.070, (stress at 200% elongation) / (rupture strength) = 0.035 to 0.150 The polyurethane fiber according to any one of claims 1 to 5, characterized in that: 7. A modified polycarbonate diol and an alicyclic diisocyanate are reacted under solvent-free conditions, then dissolved in dimethylacetamide, and ethylenediamine and a secondary monoamine as a reaction terminator are added to the solution. React at -60 ° C and adjust the solution concentration to 30-4
Polyurethane fiber obtained by dry-spinning a polyurethane solution having a solution viscosity of 2000 to 6000 poise, a high-temperature side melting point of 200 ° C. to 250 ° C. and a number average molecular weight of 40,000 to 150,000. Recipe. 8. The speed ratio between the godet roller and the winder is 1.3.
8. The method for producing a polyurethane fiber according to claim 7, wherein the polyurethane fiber is wound from 0 to 1.65.