JP2001172822A - Polyurethane urea elastic fiber with excellent heat resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyurethane urea elastic fiber which is excellent in elastic function and heat resistance and does not cause trouble in a production process. SOLUTION: Ethylenediamine and the following general formula (1)
A polyurethane urea polymer chain-extended with a mixed diamine consisting essentially of a diamine represented by the formula: wherein the content of the diamine of the general formula (1) is 10 to 10
A polyurethane urea elastic fiber characterized by being in a range of 30 mol%. Embedded image (Wherein X and Y are each - (CH ₂₎ n-a shows, n represents an integer of 1 to 3).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyester fiber having high elasticity, high elongation and high heat resistance, and maintains high elasticity and high elongation even when dyed under high temperature, high pressure and wet heat conditions. The present invention relates to a polyurethane urea elastic fiber having excellent moisture and heat resistance suitable for the production of mixed garments such as mixed knitted fabrics.

[0002]

2. Description of the Related Art Polyurethane elastic fibers are mainly knitted and knitted with nylon fibers, and are widely used in the fields of foundation, pantyhose, sock opening rubber and the like. However, the use of cross-knitted fabrics of polyester fibers and polyurethane elastic fibers, which are typical general-purpose synthetic fibers, in clothing in the outer field is limited. The main reason is that the dyeing of polyester fibers requires much more severe wet and heat temperature (about 130 ° C) than the dyeing of nylon fibers dyed at dyeing temperature of about 100 ° C, and the mixed polyurethane elasticity. The heat resistance of the fibers was not sufficient. Therefore, when the polyester fiber / polyurethane elastic fiber mixed product manufactured by the conventional technology is dyed under the general dyeing conditions of general-purpose polyester fiber, the polyurethane elastic fiber is largely heat-set (heat set), and the power is greatly reduced. In addition, the breaking strength was significantly reduced, or in some cases, the material was thermally cut. In addition, when the heat resistance of the polyurethane elastic fiber is not sufficient, there is a risk that the polyurethane elastic fiber may be thermally cut during high-temperature molding such as coupling of a bra.

However, in recent years, in the field of outer clothing and the field of sports (skiing, skating, golfing, etc.), a composite fabric material comprising stretchable polyester fibers of various colors and polyurethane elastic fibers has been desired. Polyurethane urea used for the production of polyurethane urea fiber is a polymer prepared by reacting a polymer diol with an excess molar amount of diisocyanate to synthesize a prepolymer having a terminal isocyanate group, and then chain-extending with a diamine compound. Since the urea group contained in the polymer forms a hard segment containing strong intermolecular hydrogen bonds, as is well known, the hard segment in the polymer forms a physical cross-linking point, and the heat resistance of the polyurethane urea is increased. Improve the quality. A polymer formulation in which the ratio of the molar amount of diisocyanate / the molar amount of polymer diol (n value) is increased to increase the hard segment content in order to improve heat resistance and elastic properties can be easily envisioned. In the formulation, the viscosity of the polymer solution must be high, and the viscosity of the polymer solution becomes unstable with time and sometimes gels, so that industrial use is difficult.

[0004] In order to improve the heat setting property, a diamine such as a urethane urea polymer chain-extended with an 80/20 mol mixture of ethylenediamine and hydrogenated m-phenylenediamine (1,3-diaminocyclohexane) is used in the chain extension step. The use of a mixture is described in US Pat.
No. 803, U.S. Pat. No. 3,507,834, and U.S. Pat. No. 3,549,596. Urethane urea polymers using diamine mixtures used in these known techniques are generally known to have reduced viscosity and improved stability over time. However, the combination of these known diamines reduces the elastic function of the resulting polyurethane urea elastic fiber,
When used in a mixed state such as cross-knitting with polyester fibers that require high-temperature and high-pressure dyeing, there is a problem that generally desired elastic performance is insufficient.

[0005] 2-methyl-1,
JP-A-3-97915 discloses a method in which 5-pentanediamine is used for chain extension in a range of 28 to 32 mol%. However, in this combination of diamines, the n value is 1.7 or more and the number average molecular weight of the polymer is 45,000.
When it is designed to be 0 or more, the viscosity stability of the polymer is not sufficient.

[0006]

An object of the present invention is to provide a polyurethane urea elastic fiber having high elasticity, high elongation and high heat resistance. A more specific object of the present invention is to provide a polyurethane urea elastic material having excellent heat resistance such that a mixed fabric product such as a knitting of polyester fiber and polyurethane urea elastic fiber does not lose its elastic performance even under high temperature and high pressure dyeing. To provide fibers.

[0007]

Means for Solving the Problems The inventors of the present invention have added a general formula (1) described below to a part of a chain extender in the preparation of polyurethane urea in the production of polyurethane urea elastic fiber.
By using the polyurethane urea obtained by mixing the specific diamine shown in with a commonly used diamine such as ethylene diamine, the elastic performance of the polyurethane urea elastic fiber decreases even when the fiber is exposed to high temperature and high humidity. It was found not to do so, and the idea of the present invention was obtained.

[0008] That is, an object of the present invention is to provide a prepolymer comprising a polymer diol having a number average molecular weight of 1,000 to 10,000 and a diisocyanate, comprising a mixture consisting essentially of ethylenediamine and a diamine represented by the general formula (1). A polyurethane urea elastic fiber chain-extended with a diamine, which is achieved by a polyurethane urea elastic fiber in which the content of the diamine represented by the general formula (1) is in the range of 10 to 30 mol% based on all diamines.

[0009]

Embedded image

Wherein X and Y are each-(C
H ₂₎ n-a shows, n represents an integer of 1 to 3). The polyurethane urea elastic fiber according to the present invention has a high elasticity and a high elongation, and the high elasticity performance does not impair the fiber under high temperature and high humidity fiber processing conditions. It is a urea elastic fiber.

The polyurethane urea elastic fiber according to the present invention further has a molar ratio (n) of diisocyanate to poimerdiol constituting the polyurethane urea of 1.7 to 1.7.
Even a polymer solution having a high n value in the range of 2.3 can be spun while maintaining a stable viscosity during the production process. The polyurethane urea elastic fiber according to the present invention comprises a solution of polyurethane urea prepared according to the design described above,
Generally, it can be prepared by applying a wet spinning or dry spinning method.

The polyurethane urea used for fiber formation is prepared by first reacting an isocyanate prepolymer at both ends with an organic diisocyanate and a polymer diol having a number average molecular weight of 1,000 to 10,000, and then having an isocyanate at both ends. It is prepared by reacting a prepolymer with a chain extender comprising a diamine mixture containing the above-mentioned specific diamine.

The embodiment will be described below. First, an excess mole of diisocyanate groups is reacted with a polymer diol to synthesize a prepolymer which is an intermediate polymer having isocyanate groups at both terminal groups. The excess mole referred to in the present invention is the ratio of the molar amount of the diisocyanate used in the present invention / the molar amount of the polymer diol, that is, the molar ratio (n value) is 1.7 to 2.3, preferably 1.72 to 2.3.
2.0. When the composition has an n value smaller than 1.7, the elasticity in the high-temperature heat treatment is significantly reduced. Further, the n value is 2.3.
With larger compositions, it is difficult to prevent gelling of the polymer.

Usually, a diisocyanate is added to a polymer diol in the presence or absence of a solvent at a reaction temperature of 0.
The reaction is carried out at a suitable temperature of from 100 ° C. to 100 ° C. to obtain a prepolymer having both ends having isocyanate groups. In this case, a catalyst that promotes a urethanization reaction such as a tin-based organic compound or a negative catalyst that is formed of an acidic inorganic or organic compound that suppresses a side reaction such as allophanate or buret can also be used.

Here, as the diisocyanate, many examples of compounds including the following compounds are known. For example, m- and p-phenylenediisocyanate, 2,
4- and 2,6-tolylene diisocyanate, m- and p-xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyl-dimethylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, naphthylene-1 , 5-diisocyanate, 1,6-hexamethylene diisocyanate, 4,4'-cyclohexylene diisocyanate,
1,3-bis (α, α-dimethyl isocyanatomethyl)
Examples include benzene, 1,4-bis (α, α-dimethylisocyanatomethyl) benzene, tetrachloro-m- and p-xylylene diisocyanate, and isophorone diisocyanate. Preferably, a diisocyanate compound having a benzene ring or a cyclohexane ring is 4,4'-diphenylmethane diisocyanate.

The number average molecular weight of the present invention is from 1,000 to 1,000.
Examples of 10,000 polymer diols include homopolymers and copolymers obtained by polymerizing ring-opening-polymerizable monomers such as ethylene oxide, propylene oxide, tetrahydrofuran, methyltetrahydrofuran, oxetane, methyloxetane, and dimethyloxetane. A polymer or a compound having two or more hydroxyl groups in one molecule, such as a linear or branched alkylene glycol having 2 to 10 carbon atoms, and a specific example of tetrahydrofuran Polyether diols such as copolymers obtained by polymerizing neopentyl glycol; and one or more dibasic acids selected from adipic acid, sebacic acid, maleic acid, itaconic acid, etc., and ethylene glycol, propylene glycol, , 4-butanediol, hexamethylene glycol Call, neopentyl glycol, and polyester diols obtained from one or more such glycols as diethylene glycol, poly -ε-
It is a homo- or copolymer of caprolactone diol, a polycarbonate diol, a polyether ester diol, a polyether carbonate diol, a polyester carbonate diol, or the like made from a straight or branched alkylene glycol having 2 to 10 carbon atoms as a raw material.
A preferred example is a number average molecular weight of 1,000 to 10,000.
Polyether diols, particularly preferred are polytetramethylene ether glycols (PTMG) having a number average molecular weight of 1,500 to 2,200.

After synthesizing the intermediate polymer, that is, the prepolymer, a chain extension reaction is then carried out with a mixture of a prepolymer having isocyanate groups at both terminal groups and a bifunctional diamine to obtain a polyurethane urea. In this case, in the present invention, as described above, the chain extender uses a mixture of two kinds of diamines. It is important to use ethylenediamine as the first diamine and diamine represented by the general formula (1) as the second diamine. By this combination, hydrogen bonding in the hard segment in the polymer is suppressed, and no increase in viscosity with time is observed even in a polymer composition having a high n value. Among the diamines of the general formula (1), X
= 1, Y = 1, the compound 1,3-bisaminomethylcyclohexane (1,3-BAC) is particularly preferred. A diamine compound in which X or Y is 4 or more tends to significantly reduce the effect of suppressing the increase in viscosity.

Examples of the diamine to be mixed are:
Examples include 3-diaminocyclohexane, 1,3-propylenediamine, and 2-methyl-1,5-pentanediamine. However, these diamine mixtures have n values of 1.
With a prepolymer composition of 7 or more, if the number average molecular weight of the polymer is 45,000 or more, the effect of suppressing the increase in the viscosity of the polyurethane urea solution is not sufficient. Also, 1,3-diaminocyclohexane, 1,3-propylenediamine, 2-
By increasing the content of methyl-1,5-pentanediamine, the effect of suppressing the increase in polymer viscosity is increased.
It was recognized that the elastic properties were reduced and the heat resistance was reduced.

The mixing ratio of ethylenediamine and the diamine of the general formula (1) in the present invention is preferably in the range of 10 to 30 mol% of the diamine of the general formula (1) with respect to all diamines. More preferably, the content is 15 to 20 mol%. When the content of the diamine of the general formula (1) is 10
If it is less than mol%, the effect of suppressing the increase in viscosity is insufficient, and gelation of the polymer solution occurs. On the other hand, if it is 30 mol% or more, the heat-resistant cutting seconds are reduced, and the yarn is broken in the heat setting step.

When a chain extender is added, a monofunctional amine compound is added and the molecular weight of the polymer is adjusted by a terminal termination reaction to obtain a polyurethane urea polymer.
In this case, the amino-reactive group equivalent of the difunctional diamine mixture or the total amino-reactive group equivalent of the bifunctional diamine mixture and the monofunctional amine compound with respect to the isocyanate group equivalent in the prepolymer is substantially equal or the amino-reactive group The equivalent may be excessive.

It is also possible to use the bifunctional diamine mixture in excess of the isocyanate groups and react the bifunctional diamine mixture as a monofunctional amine compound. That is, in this case, an excess amino group equivalent of the bifunctional amine compound relative to the isocyanate group equivalent remains unreacted with the polymer terminal group as one terminal amino group, and functions as a polymer molecular weight modifier.

As another modified embodiment, when a monofunctional amine compound is used as a polymer molecular weight modifier during the polymerization of polyurethane urea, examples of the monofunctional amine compounds include diethylamine, dimethylamine, methylethylamine, methylisopropyl Amine, methyl-n-
Propylamine, diisopropylamine, methyl-n-
Butylamine, methyl-isobutylamine, methylisoamylamine and the like. When a monofunctional amine compound is used, it may be added to the prepolymer and reacted before the bifunctional diamine mixture, or may be added and reacted simultaneously. The amount of the monofunctional amine compound used is 40% of the total amine equivalent supplied to the prepolymer.
% Equivalent or less is appropriate.

The reaction between the prepolymer and the amine compound is as follows:
Extremely fast. In order to carry out the reaction gently, a low temperature can be used as long as the reaction temperature is not lower than the melting point of the reaction solvent to be used and the temperature does not cause the prepolymer to precipitate from the solvent. When using a low melting polymer diol,
Reaction at a low temperature of several tens of degrees below freezing is also possible. A solvent may optionally be used during the synthesis of the prepolymer or during the reaction between the prepolymer and the amine compound. Examples of solvents include dimethylformamide, dimethylacetamide,
Dimethyl propionamide, dimethyl sulfoxide,
N-methylpyrrolidone and the like.

When a solvent is used, the polymer solid content concentration is usually 25 to 50% by weight. 30-40% is more preferred. If it is 25% or less, a long spinning cylinder is required to evaporate the solvent in the dry spinning method, which is not industrial. If it is 50% or more, it is difficult to prevent gelation of the polymer. Polymer solution applied to spinning, further, known antioxidants, anti-coloring agents, stabilizers such as ultraviolet absorbers,
Additives and fillers (metal stearates, magnesium oxide, hydrotalcite, zinc oxide) such as pigments such as titanium oxide, antistatic agents and fungicides, and dry or wet the fiber with a spinning machine. Obtainable. After the spun yarn is false-twisted, a stearic acid salt or the like of an oil agent or a lubricant is applied. The type of the oil agent is not particularly limited, but is modified by introducing polydimethylsiloxane, diorganosiloxane in which a part of the methyl group of the polydimethylsiloxane is substituted with another alkyl group or phenyl group, amino group, vinyl group, epoxy group, etc. Polysiloxane organopolysiloxanes and mineral oils are preferred.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. The method of measuring the characteristic values in the examples will be described below. [1] Measurement of Molecular Weight of Polymer The polymer is dissolved and diluted in dimethylacetamide (DMAC) to prepare a 0.5% by weight sample solution. Gel permeation chromatography (GPC)
The measurement was performed under the following conditions using a system 11 manufactured by Shodex.

Column: SB-806 manufactured by Shodex
M (2) and SB-802.5 (1) Solvent: DMAC Flow rate: 1.0 ml / min Column bath temperature: 60 ° C. Sample volume: 100 μl Detector: RI Number average molecular weight (Mn) and weight average molecular weight (Mw)
Was determined from calibration values obtained with standard PTMG samples. [2] Measurement of viscosity of polymer solution Measured at 30 ° C. using an E-type viscometer RE110U system manufactured by Toki Sangyo Co., Ltd. [3] Measurement of fiber breaking strength and elongation The fiber was measured using a Tensilon UTM-III-100 type tensile tester manufactured by Orientec, at a temperature of 20 ° C and a humidity of 65%. A sample having a sample length of 5 cm is measured for strength and elongation at break when the sample is stretched at a speed of 50 cm / min. [4] Heat resistance test of fiber High temperature and high pressure dyeing machine (NISSEN CORPORATION)
(N TYPE 12LMP-E). Elongate the test yarn of 50 mm to 80% by 90%
mm, and immersed in ion-exchanged water in a pot inside the dyeing machine for treatment. The processing conditions are as follows.
The temperature was raised at a rate of 5 ° C./min, kept at 130 ° C. for 3 hours, and then cooled and depressurized. The specimen taken out from the dyeing machine
The fabric was air-dried all day and night in an atmosphere of a temperature of 20 ° C. and a humidity of 65%, and the following properties of the treated fiber were measured.

Measurement of elongational stress recovery rate (residual strain) of fiber: Tensilon UTM-III-10 manufactured by Orientec
The measurement was performed using a 0-type tensile tester under the conditions of a temperature of 20 ° C. and a humidity of 65%. Pull at 1,000% / min.
The recovery was stopped at a rate of 1000% / minute, and the recovery was repeated three times, and the residual strain was measured when the tension became zero.

Measurement of the Fiber Retention Strength The ratio (%) of the rupture strength after heat treatment to the rupture strength before heat treatment was defined as the strength retention. Strength retention (%) = (Tsa / Tsb) × 100 Tsa: breaking strength after heat treatment (g) Tsb: breaking strength before heat treatment (g) [5] Measurement of heat-resistant cutting seconds of fiber 140 mm Elongate the test yarn by 50% to 210
mm and pressed against a 180 ° C heat source (contact
m), the number of seconds until disconnection was measured.

Example 1 P having a number average molecular weight of 2,000
223 g of TMG and 50.4 g of 4,4'-diphenylmethane diisocyanate were dried under dry nitrogen at 80 ° C. for 3 hours.
The reaction was performed under stirring to obtain a prepolymer. After cooling to room temperature, 414.4 g of dimethylacetamide was added and dissolved with stirring at room temperature to obtain a uniform prepolymer solution. On the other hand, ethylenediamine, 4.30 g, 1,
3-BAC, 0.43 g, diethylamine, 0.88 g
Was dissolved in 17.53 g of DMAC to prepare an amine solution. The molar ratio of the mixed diamine in this amine solution is ethylenediamine / 1,3BAC = 80/20. The amine solution was added at a stretch to 707.4 g of the prepolymer solution under high-speed stirring, and then 120.7 g of DMAC was further added. The mixture was allowed to react at room temperature for 1 hour, at a concentration of 34.1% by weight and an n value of 1.
75 polyurethaneurea solutions were obtained.

The molecular weight of this polyurethane urea solution is represented by G
When measured by PC, Mw = 139,440, Mn = 4
6,480. The viscosity of the polymer solution immediately after the polymerization (day 0) was 2,930 poise. When this polymer solution was stored at 25 ° C., the time-dependent change in viscosity (1 day, 4 days,
Table 1 shows the measurement results obtained on day 7). Example 2 In Example 2, polymerization was carried out while changing the mixing ratio of diamine and the final polymer concentration. That is, according to the method of Example 1, ethylenediamine / 1,3-BA
C = 80/20 (molar ratio), n value = 1.75, concentration 3
0.4% by weight of polymer and ethylenediamine / 1,
3-BAC = 90/10 (molar ratio), n value = 1.70,
A polymer solution having a concentration of 35% by weight was synthesized. Daily changes in molecular weight, solution viscosity and viscosity of these polymers (1.
Days, 4 days, and 7 days) are shown in Table 1.

Comparative Example 1 1, 3 in Examples 1 and 2
A polyurethaneurea solution was synthesized according to Example 1 using 1,3-diaminocyclohexane (1,3-DACH) and 1,3-propylenediamine (PDA) instead of -BAC. That is, ethylenediamine /
1,3-DACH = 90/10 (molar ratio), n value = 1.
70, 35% by weight polymer and ethylenediamine / PDA = 80/20 (molar ratio), n value = 1.75,
A polymer having a concentration of 30.4% by weight was synthesized. Table 1 shows the molecular weight, solution viscosity and change over time of the viscosity of these polymers.
Shown in

In the polymer using 1,3-DACH and PDA as the mixed diamine, the viscosity of the polymer increased with time, and the polymer gelled after 10 days. Example 3 and Comparative Example 2 The viscous polymer solutions obtained in Examples 1 and 2 and Comparative Example 1 were added with 4,4'-butylidene-bis (3
-Methyl-6-t-butylphenol) 2%), 2-
0.7% of (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chloro-benzotriazole
To which a spinning dope was added.

[0033]

[Table 1]

Polyurethane urea fibers of 44 dtex were obtained from these spinning stock solutions by ordinary dry spinning at a spinning speed of 400 m / min. Table 2 shows the measurement results of the breaking strength, breaking elongation, and heat-resistant cutting seconds. These polyurethane fibers were heat-treated, and the results of measuring the strength retention before and after the treatment and the elongation stress recovery after the treatment are shown in Table 2. In the polymer using 1,3-DACH and PDA as the mixed diamine, the spinning solution was partly gelled, so that the spinning state was unstable and thread breakage often occurred. Also,
The urethane urea elastic yarn obtained from the polymer using 1,3-DACH and PDA showed a larger decrease in elastic properties due to the heat treatment than 1,3-BAC.

[0035]

[Table 2]

[0036]

The polyurethane urea elastic fiber according to the present invention is a polyurethane urea elastic fiber having excellent elasticity and heat resistance and capable of withstanding polyester dyeing conditions of high temperature, high pressure and humidity. The polyurethane urea elastic fiber according to the present invention has excellent storage stability of polyurethane urea, and can prepare a spinning solution having a small change in viscosity during storage at room temperature. Can be manufactured under

Continued on front page F term (reference) 4J034 BA08 CA15 CB03 CC03 CC05 CC23 CC26 CC45 CC52 DA01 DB03 DB07 DC50 DF01 DF02 DF12 DG01 DG02 DG03 DG04 DG06 DG08 DG10 HA07 HC12 HC17 HC22 HC46 HC52 HC61 HC64 JA42 QA03 QA05 QB03B BB11 DD14 EE01 EE08 EE20 GG04 HH01 HH04 HH10 MH02 MH09 MH13

Claims (2)

[Claims] 1. A number average molecular weight of 1,000 to 10,000.
Is a polyurethaneurea elastic fiber obtained by chain-extending a prepolymer comprising a polymer diol and a diisocyanate with a mixed diamine consisting essentially of ethylenediamine and a diamine represented by the general formula (1). The polyurethane urea elastic fiber is characterized in that the content of the diamine is in the range of 10 to 30 mol% based on the total diamine. Embedded image (Wherein X and Y are each - (CH ₂₎ n-a shows, n represents an integer of 1 to 3). 2. The molar amount of diisocyanate / the molar amount of polymer diol (n value) is in the range of 1.7 to 2.3, and the number average molecular weight of the polymer is 45,000 or more. The polyurethane urea elastic fiber according to claim 1, wherein