KR101167377B1 - Process for Preparing polyurethaneurea elastic fiber with improved heat settable properties - Google Patents

Abstract

The present invention provides an elastic yarn comprising a polyurethane urea based on a polyol, a first diisocyanate, a second diisocyanate and a chain extender, wherein the first diisocyanate is one selected from aromatic, aliphatic and alicyclic diisocyanates or At least two organic diisocyanates, wherein the second diisocyanate is isophorone diisocyanate, and the second diisocyanate is in the range of about 2 to about 25 mole% of the total diisocyanate. It is a way. Polyurethane urea elastic yarn prepared by the above method is excellent in thermal setting properties, the interwoven fabric using the elastic yarn is excellent in the touch (touch) of the fabric without generating the edge curl of the interwoven fabric even if the heat setting at a low temperature.

Polyurethaneurea elastic yarn, 1st diisocyanate, 2nd diisocyanate, curling edge, heat setting

Description

 Process for Preparing polyurethaneurea elastic fiber with improved heat settable properties

The present invention relates to a method for producing a polyurethane urea, and more particularly, the diisocyanate of the polyurethane urea is obtained by mixing isophorone diisocyanate with at least one diisocyanate including 4,4'-diphenylmethane diisocyanate. It relates to a polyurethane urea characterized in that it is produced and an elastic yarn having excellent heat setability produced using the same.

More specifically, by making an elastic yarn having excellent heat setability even at a low temperature, heat setting the heat sensitive fibers and interwoven fabrics at low temperature to prevent embrittlement of the heat sensitive fibers by heat and to avoid curling of the fabric. It's all about making technology.

 Polyurethaneurea is generally a primary polymerization reaction of reacting a polyol, a high molecular weight diol compound, with an excess of a diisocyanate compound to obtain a prepolymer having an isocyanate group at the end of the polyol, and the prepolymer in an appropriate solvent. After dissolving, the solution is added with a diamine-based or diol-based chain extender and reacted with a chain terminator such as monoalcohol or monoamine, followed by making a spinning solution of polyurethaneurea fiber, followed by dry and wet spinning. The elastic fiber is obtained by.

Polyurethane urea fibers are actively used for various applications because of their inherent characteristics with high elasticity, and as the range of applications thereof expands, new additional characteristics of existing fibers continue to be demanded.

In general, polyurethaneurea fibers had a problem that thermal embrittlement of heat-sensitive counterparts (nylon, cotton, silk, wool) occurs in post-processing after knitting due to high heat setting temperature. In order to prevent this problem and improve the appearance of the fabric, there is a growing demand for polyurethaneurea fibers that can be set at low temperatures.

In response, efforts have been made to improve the heat setability of polyurethane-based elastic fibers. For example, Japanese Patent Laid-Open Nos. 63-53287, 63-53288, 43-3939, Japanese Patent Laid-Open No. 7-316922, Korean Patent Laid-Open No. 2001-5854, and Korean Patent Laid-Open 2001 -16788 discloses a method for improving the thermosetability of polyurethane elastic yarns.

In addition, U.S. Patent No. 6,403,682, U.S. Patent 6,376,071, U.S. Patent 6,063,892, U.S. Patent 5,981,686,5,948,875 and the like disclose methods for improving the heat setability of polyurethane elastic yarns, but still at low temperatures. Because of this lack, it is not applicable to heat sensitive fibers and the like.

In addition, Japanese Patent Application Laid-open No. Hei 7-82608 and U.S. Patent No. 6,472,494 attempt to improve physical properties by applying 2,4'-diphenylmethane diisocyanate, but are accompanied by heat setability or a decrease in modulus and elastic recovery rate. .

The diisocyanate used in the production of the polyurethaneurea elastic yarn according to the present invention includes a first diisocyanate and a second diisocyanate, and the first diisocyanate is one or two selected from aromatic, aliphatic and alicyclic diisocyanates. At least one organic diisocyanate, wherein the second diisocyanate is isophorone diisocyanate and the second diisocyanate is present in the range of about 2 to about 25 mole percent of the total diisocyanate.

In this way, the elastic yarn having excellent heat setability is improved in the state of the fabric by heat setting the heat-sensitive fiber and interwoven fabric at low temperature so that thermal embrittlement does not occur, and edge curling does not occur.

The present invention is to produce a polyurethane urea elastic yarn with improved heat setability, by performing heat setting at a low temperature does not cause thermal embrittlement of the other company can improve the appearance of the fabric than the conventional, and the rim curl in the processed paper after heat setting Does not occur.

Hereinafter, the method of manufacturing the polyurethaneurea elastic yarn of this invention is demonstrated in detail. The segmented polyurethaneurea used in the preparation of the elastic yarn of the present invention is prepared by reacting an organic diisocyanate with a polymer diol to prepare a prepolymer, dissolving it in an organic solvent, and then reacting with a diamine and a monoamine.

The diisocyanate used in the production of the polyurethaneurea elastic yarn used in the present invention includes a first diisocyanate and a second diisocyanate. The first diisocyanate is one or two or more organic diisocyanates selected from aromatic, aliphatic and alicyclic diisocyanates, specifically 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate , 1,5'-naphthalene diisocyanate, 1,4'-phenylene diisocyanate, hexamethylene diisocyanate, 1,4'-cyclohexane diisocyanate, 4,4'-dicyclohexyl methane diisocyanate, isophorone diisocyanate Etc.

The second diisocyanate is isophorone diisocyanate, and the content of isophorone diisocyanate is suitably 2 to 25 mole% of the total diisocyanate.

In general, when producing a polyurethane urea elastic yarn, 4,4'- diphenylmethane diisocyanate is used due to the physical properties of the fiber. However, the isophorone diisocyanate used in small amounts in the present invention has a three-dimensional structure unlike the existing 4,4'-diphenylmethane diisocyanate. Hydrogen bonds are formed in a coarse shape, and have substantially the same effect as an increase in the content of the soft segment rather than the hard segment. Therefore, by forming a lot of soft domains (elastic fibers) excellent in the setability can be obtained. If the content of isophorone diisocyanate is less than 2%, the settability improvement effect is insufficient, and if the content of isophorone diisocyanate exceeds 25 mol%, the yarn modulus rapidly decreases. It is preferable to be inside.

In addition, the polymer diol may be exemplified as one kind or a mixture of two or more kinds thereof in polytetramethylene ether glycol, polypropylene glycol, polycarbonate diol and the like.

Diamines are used as chain extenders, and examples thereof include ethylenediamine, 1, 2-diaminopropane, 1, 3-diaminopropane, 1,4-diaminobutane, 2,3-diaminobutane, 1,5 One kind or a mixture of two or more kinds thereof, such as -diaminopentane, 1, 6-hexamethylenediamine and 1,4-cyclochlorodiamine, can be exemplified.

In order to control the molecular weight of the polyurethaneurea, amines having a monofunctional group, for example, diethylamine, monoethanolamine, dimethylamine and the like can be used.

In addition, in the present invention, in order to prevent discoloration and deterioration of the physical properties of the polyurethane urea due to ultraviolet rays, atmospheric smog, heat treatment process associated with spandex processing, etc., the steric hindrance phenol compound, benzofuran-one compound, and semicarbazide in the spinning stock solution. Type compound, a benzo triazole type compound, a polymeric tertiary amine stabilizer, etc. can be added combining them suitably.

Furthermore, the polyurethaneurea elastic yarn of the present invention may include additives such as titanium dioxide, magnesium stearate, and the like in addition to the above components.

Hereinafter, the present invention will be described in more detail with reference to examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

In Examples and Comparative Examples to be described later, the NCO% measurement method of the polyurethaneurea polymer, the heat setability of the yarn, and the edge curl of the fabric were measured as follows.

* NCO % Measurement

NCO% = [100 * 2 * NCO chemical formula * (capping ratio-1)] / {(diisocyanate molecular weight * capping ratio) + polyol molecular weight}

Where the capping ratio is the diisocyanate molar ratio / polyol molar ratio.

* Heat Setability of Yarn

The initial yarn (L0) was 100% elongated (L1) while exposed to the atmosphere, and then subjected to dry heat treatment at 170 ° C. for 1 minute, cooled to room temperature, and then the length (L2) of the yarn was measured. Dry heat-treated yarn was moist-heated at 100 ° C. for 30 minutes in a relaxed state and dried at room temperature to measure the length (L3) of the yarn. The dry heat setability and heat set efficiency of the yarn was determined according to the following equation. HSE) was calculated.

Dry Heat Setability (%) = {(L2-L0) / (L1-L0)} X 100

HSE (%) = {(L3-L0) / (L1-L0)} X 100

* Elongation of yarn

Using an automatic elongation measuring device (MEL machine, Textechno Co., Ltd.), measure the sample length as 10cm and tensile speed 100cm / min. At this time, the strength and elongation at break are measured, and the load on the yarn (200% modulus) at 200% elongation of the yarn is also measured.

* Edge curl (Curling)

The elastic knitted fabric and nylon yarn were manufactured using a circular knitting machine having a diameter of 32 inches, a 28 gauge, and a 96 feeder. The circular knitted fabric was knitted using 70 denier of nylon yarn and 40 denier of elastic yarn prepared above, and the content of elastic yarn was 8% of the total weight of the knitted fabric. to be.

The circular knitting fabric made of interlaced nylon / polyurethane urea elastic yarn is treated with pre-setting, dyeing, and final-setting to display an equilateral triangle with a length of 5 cm and then cut two sides. Was sprinkled onto the fabric and dried. After drying, it was calculated as the ratio of the area rolled up from the measurement fabric and the area of the initial equilateral triangle.

Curling% = (area of curled triangle / area of original equilateral triangle) X 100

If the ratio of the area to be rolled up within 10% generally means that the edge curl is good.

< Example  1>

Capping ratio (CR) was prepared at a content of 1.65, 5 mol% of isopron diisocyanate and 95 mol% of 4,4'-diphenylmethane diisocyanate. The chain extender used ethylenediamine and 1,2-diamino propane mentioned above, and the chain stopper used diethylamine. The ratio of the chain extender and the chain dispersant was 12.5: 1, and the ratio of ethylenediamine and 1,2-diamino propane was 80 mol% and 20 mol%. The amine used was prepared in a total concentration of 7 mol%, and dimethylacetamide was used as a solvent. That is, 0.64 kg of isophorone diisocyanate, 12.2 kg of 4,4'-diphenylmethane diisocyanate, and 55.8 kg of polytetramethylene ether glycol (molecular weight 1800) are reacted with stirring at 90 ° C. for 180 minutes in a nitrogen gas stream, and both terminals are reacted. Polyurethaneurea prepolymers with isocyanates were prepared. After cooling the prepolymer to room temperature, the prepolymer and dimethylacetamide at 65.66 g / min were fed at 44.57 g / min to obtain a polyurethaneurea prepolymer solution. Then, an amine solution prepared from 979 g of ethylene diamine, 301.9 g of 1,2-diaminopropane, 119.1 g of diethylamine, and 18.6 kg of dimethylacetamide was added to the prepolymer solution at 10 ° C. or lower to 122.8 g of polyurethaneurea per minute. A solution was obtained.

Ethylenebis (oxyethylene) bis- (3- (5- t -butyl-4-hydroxy- m -toyl) -propionate) 1.5% by weight, 5,7-di- t as an additive relative to the solid content of the polymer -Butyl-3- (3,4-dimethylphenyl) -3H-benzofuran-2-one 0.5% by weight, 1,1,1 ', 1'-tetramethyl-4,4'-(methylene-di- p 1 weight% of -phenylene) dicicacarbide, 1 weight% of poly (N, N-diethyl-2-aminoethyl methacrylate), and 0.1 weight% of titanium dioxide were added and mixed to obtain a polyurethaneurea spinning stock solution.

The spinning stock solution obtained as described above was prepared by polyurethane spinning yarns of 40 denia 3 filament at a speed of 900m / min, and the physical properties are shown in Table 1 below.

< Example  2>

It is the same as Example 1 except the polyurethaneurea polymer was manufactured by the ratio of 10 mol% of isophorone diisocyanate and 90% of 4,4'- diphenylmethane diisocyanate. The obtained spinning stock solution prepared a polyurethane urea elastic yarn of 40 denier 3 filament at a speed of 900m / min, and evaluated the physical properties are shown in Table 1 below.

< Example  3>

It is the same as Example 1 except the polyurethane urea polymer was manufactured by the content ratio of 25 mol% of isophorone diisocyanate and 75% of 4,4'- diphenylmethane diisocyanate. The obtained spinning stock solution prepared a polyurethane urea elastic yarn of 40 denier 3 filament at a speed of 900m / min, and evaluated the physical properties are shown in Table 1 below.

< Comparative example  1>

It was prepared under the same conditions as in Example 1 except that no isophorone diisocyanate was added. That is, 12.93 kg of 4,4'-diphenylmethane diisocyanate and 55.8 kg of polytetramethylene ether glycol (molecular weight 1800) are reacted with stirring at 90 ° C. for 90 minutes in a nitrogen gas stream, and polyurethaneurea having isocyanate at both ends. Prepolymers were prepared. After cooling the prepolymer to room temperature, the prepolymer and dimethylacetamide at 65.66 g / min were fed at 44.57 g / min to obtain a polyurethaneurea prepolymer solution. Then, an amine solution prepared from 979 g of ethylene diamine, 301.9 g of 1,2-diaminopropane, 119.1 g of diethylamine, and 18.6 kg of dimethylacetamide was added to the prepolymer solution at 10 ° C. or lower to 122.8 g of polyurethaneurea per minute. A solution was obtained. The spinning stock solution obtained as described above was prepared by polyurethane spinning yarn of 40 denier 3 filament at a speed of 900m / min, and the physical properties are shown in Table 1 below.

 Additive composition, spinning conditions, etc. of this polymer are the same as Example 1.

< Comparative example  2>

Except that the content of isopron diisocyanate 30 mol% was carried out in the same manner as in Example 1 to prepare a polyurethane urea elastic yarn, the physical properties are shown in Tables 1 and 2.

[Table 1]

As shown in [Table 1], the isophorone diisocyanate content was mixed at 5 mole% or more, and it was confirmed that the heat setability was improved. When the mixture is prepared by mixing at least 30 mole%, the heat setability is greatly improved, but the modulus decreases. It can be seen that the larger.

[Table 2]

Presetting temperature (℃) Finish setting temperature (℃) Fecal swelling (%) Touch Example 2 170 160 3 Great Example 3 170 160 0 Great Comparative Example 1 190 180 0 Bad Comparative Example 2 170 160 100 Great

When fabricating the nylon circular knitted fabric as shown in the [Table 2] Example 2 and Example 3 fabrics made of yarn compared to the fabric produced by Comparative Example 1 heat setting temperature lowered about 20 ℃ heat setting is The edge curl does not occur even if it is carried out. As a result, it does not generate thermal embrittlement of nylon, so the fabric has a very good appearance, and cost reduction is achieved by lowering the heat setting temperature.

Claims (4)

Polyurethane and diisocyanate were first polymerized to obtain a prepolymer, and then a polyurethane urea elastic yarn was prepared by adding a chain extender to the solution obtained by dissolving the prepolymer in an organic solvent to perform a second polymerization. In the method, The diisocyanate includes a capping ratio (CR) of 1.65, a first diisocyanate and a second diisocyanate, and the first diisocyanate is one or two or more organic diisocyanates selected from aromatic, aliphatic and alicyclic diisocyanates. Wherein the second diisocyanate is isophorone diisocyanate, and the second diisocyanate is mixed so as to exist in the range of 2 to 25 mol% of the total diisocyanate, but the chain extender and the chain terminator in a ratio of 12.5: 1. A method of producing a polyurethaneurea elastic yarn, characterized in that to obtain a polyurethane urea spinning stock solution and to obtain a polyurethane urea elastic yarn of 40 denia 3 filament at a speed of 900m / min by the spinning spinning solution obtained by using. The diisocyanate of claim 1, wherein the diisocyanate is 4,4'-diphenylmethane diisocyanate, 1,5'-naphthalene diisocyanate, 1,4'-phenylene diisocyanate, hexamethylene diisocyanate, 1,4'-cyclohexane A method for producing a polyurethaneurea elastic yarn, characterized in that one or two or more selected from the group consisting of diisocyanate, 4,4'-dicyclohexyl methane diisocyanate, and isophorone diisocyanate are used. The method of claim 1, wherein the polyol of the prepolymer is prepared by mixing one or two or more selected from the group consisting of polytetramethylene ether glycol, polypropylene glycol, and polycarbonate diol. The chain extender of claim 1 wherein the chain extender is ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 2,3-diaminobutane, 1,5-di A method for producing a polyurethaneurea elastic yarn prepared by mixing one or two or more selected from the group consisting of aminopentane, 1,6-hexamethylenediamine and 1,4-cyclohexanediamine.