KR101620573B1 - Polyurethanurea elastic fiber with good unwinding performance and method of manufacturing the same - Google Patents

Abstract

The present invention relates to a polyurethane-urea elastic yarn excellent in marine property and a method for producing the same, and more particularly, to a polyurethane-urea elastic yarn excellent in marine property, Characterized in that the average value of the cross-sectional profile of the elastic yarn is 2.0 to 3.5 and the standard deviation thereof is 0.01 to 1.0. The polyurethane-urea elastic yarn has a peanut-shaped cross section and a method for producing the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a polyurethane-urea elastic yarn having excellent marine properties and a method for producing the same.

The present invention relates to a polyurethane-urea elastic yarn excellent in marine property and a method for producing the same, and more particularly, to a polyurethane-urea elastic yarn excellent in marine property, A polyurethane-urea elastic yarn having a peanut-shaped cross-section having an average value of cross-sectional heterogeneity of 2.0 to 3.5 and a standard deviation of cross-sectional heterogeneity of 0.01 to 1.0, and a method for producing the same.

Fibers and film-like polyurethaneureas with elastic properties are widely used in the textile industry. The term ' spandex ' as used to describe these elastic polyurethaneureas often refers to long chain synthetic polymers composed of at least 85% by weight of segmented polyurethanes. Spandex has been used in the textile industry for a variety of purposes, particularly underwear, form-guided clothing, swimwear and elastic garments or stockings.

The elastic yarn may itself be supplied as staple fiber, either as a core-spun elastomer yarn spun circularly with a filament or staple fiber yarn for the purpose of improving the wearing quality of the fabric having a low elasticity, or as a staple fiber mixed with non-elastic fibers.

The polyurethaneurea is prepared by reacting a polyol which is generally a high molecular weight diol compound with an excessive diisocyanate compound to obtain a prepolymer having isocyanate groups at both terminals of the polyol and a prepolymer obtained by reacting the prepolymer with an appropriate solvent After the solution is dissolved, a diamine-based or diol-based chain extender is added to the solution to react with a chain terminator such as a monoalcohol or a monoamine, etc. to prepare a spinning solution of the polyurethane-urea fiber, followed by drying and wet spinning To obtain a polyurethane-urea elastic yarn, that is, a spandex fiber.

Polyurethane-urea elastic yarns are used for various purposes due to their inherent properties of excellent elasticity and elastic restoring force, and as the range of applications thereof is expanded, new additional characteristics are continuously required in existing fibers.

Generally, the polyurethane-urea elastic yarn is loosened by rotating motion on the rotating body while knitting with a counter yarn (nylon, cotton, silk, wool, etc.), and the elastic yarn is loosened by a conventional circular or elliptical cross- In this case, a yarn flow problem in which the elastic yarn separates from the widthwise liner occurs, or the shape of the liner is disturbed, and a band is generated at the edge of the liner, thereby causing yarn breakage.

In order to solve the above problem, efforts have been continuously made to improve marine characteristics of polyurethane based elastic yarn. There have been some methods of improving the tackiness properties of the emulsion, which have been used most commonly in the elastic yarn manufacturer, but they have also been limited in their degree of improvement since they have the drawback that they can affect the physical properties such as refinability and marine properties.

Accordingly, the present invention relates to a process for producing a prepolymer for the production of elastic yarn, which comprises the steps of increasing the content of NCO in the range of 2.60 to 3.00% to increase the hard segment content, The use of ethylenediamine (100%) as a peanut-shaped cross-section of elastic fibers was attempted to solve the problem.

Particularly, when 100% of ethylenediamine is used as a chain extender in a polymer having an NCO% of 2.60 to 3.00%, fine phase separation increases due to an increase in the hard segment content in the polymer, The deviation of the solvent diffusion rate between the surfaces is increased, so that the cross section of the yarn can be manufactured as peanut type.

The present invention relates to a polyurethane resin composition having an NCO% of 2.60 to 3.00% in the polymerization of a polyol and a diisocyanate to produce a cross-sectional shape in a peanut shape and a polyurethane having an excellent marine property by applying 100% of ethylenediamine as a chain extender, A urea elastic yarn and a process for producing the same.

In order to accomplish the above object, the present invention provides a process for producing a polyurethane precursor, which comprises polymerizing a polyol and a diisocyanate to prepare a polyurethane precursor, and dissolving the polyurethane precursor in a solvent to prepare a prepolymer solution; Dissolving the chain extender and the chain extender in a solvent to prepare an amine solution; Stirring and chain extending the prepolymer solution and the amine solution to prepare a polyurethane-urea spinning solution; And a step of spinning and spinning the polyurethane-urea spinning stock solution, wherein the NCO% of the prepolymer is 2.5 to 3.0%, the yarn is cut perpendicular to the longitudinal direction, and the width of the cross section measured by a microscope (W / H, W: the longest straight line length crossing the yarn cross section, H: the longest straight line W of the constricted portion in the middle portion of the yarn cross section, A length of a shortest straight line intersecting vertically) of 2.0 to 3.5 and a standard deviation of a cross-sectional profile showing uniformity of the yarn thickness is 0.01 to 1.0. The present invention also provides a method for producing the polyurethaneurea elastic yarn.

At this time, it is preferable that the chain extender is 100% of ethylenediamine.

(W / H, W: cross section of the yarn (W / H, W: length of the yarn cross section) as a ratio of the width (W) the length of the shortest straight line intersecting perpendicularly with the longest straight line W of the constricted portion in the center portion of the yarn cross section) is 2.0 to 3.5 and the uniformity of the yarn thickness And the standard deviation of the cross-sectional profile is from 0.01 to 1.0.

The polyurethane-urea elastic yarn of the present invention can be manufactured in the form of peanuts in the cross-sectional shape, and the elastic yarn thus produced can provide excellent marine properties without yarn flow, thereby improving workability in post-processing such as knitting workability.

Hereinafter, the present invention will be described.

The present invention relates to a process for preparing a prepolymer solution by polymerizing a polyol and a diisocyanate to prepare a polyurethane precursor and then dissolving the polyurethane precursor in a solvent; Dissolving the chain extender and the chain extender in a solvent to prepare an amine solution; Preparing a polyurethane-urea spinning solution by stirring and chain-extending the prepolymer solution and the amine solution; And a step of spinning and spinning the polyurethane-urea spinning stock solution. The present invention also provides a method for producing a polyurethane-urea elastic yarn.

Non-limiting examples of the diisocyanate used in the production of the polyurethaneurea elastic yarn in the present invention include 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 1,5'-naphthalene diisocyanate , 1,4'-phenylene diisocyanate, hexamethylene diisocyanate, 1,4'-cyclohexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and isophorone diisocyanate. Of these diisocyanates, One or a mixture of two or more thereof, but is not limited thereto.

The polymer diol used in the present invention is a copolymer of polytetramethylene ether glycol, polytrimethylene ether glycol, polypropylene glycol, polycarbonate diol, a mixture of alkylene oxide and lactone monomer and poly (tetramethylene ether) glycol, 3- A copolymer of methyl-tetrahydrofuran and tetrahydrofuran, or a mixture of two or more thereof, but is not limited thereto.

At this time, it is preferable that the NCO% of the prepolymer is in the range of 2.6 to 3.0% in order to exhibit proper physical properties as the polyurethaneurea elasticity yarn to increase the hard segment content. If the NCO% of the prepolymer is less than 2.6% or exceeds 3.0%, a serious deterioration of the physical properties of the elastic yarn is caused.

On the other hand, as the chain extender, diamines are used, and in the present invention, it is preferable to use 100% of ethylenediamine.

As the chain terminator for the polyurethaneurea, an amine having one functional group such as diethylamine, monoethanolamine, dimethylamine, and the like can be used, but is not limited thereto.

Further, in the present invention, in order to prevent discoloration and deterioration of physical properties of polyurethane-urea by a heat treatment process accompanying ultraviolet rays, atmospheric smog and spandex processing, it is preferable to add a stereogenic phenolic compound, a benzofuran- Based compound, a benzotriazole-based compound, a polymeric tertiary amine stabilizer, and the like. Further, the polyurethane-urea elastic yarn of the present invention may contain additives such as titanium dioxide, magnesium stearate and the like in addition to the above components.

Particularly, as the cross-sectional deviation value is closer to 1.0, the elastic yarn has a uniform circular cross-section, and when the knitted fabric and the knitted fabric are knitted, when the elastic yarn is loosened by the rotational movement, the elastic yarn has a circular circular shape So that the shape of the lance is easily disturbed to form a band shape at the edge of the lance, or the lace is detached from the lace so as to cause the trimming when the lace is knitted.

The polyurethane-urea elastic yarn produced by the above-described production method is characterized in that the yarn cross-section having an average value of the cross-sectional heteromorphism of 2.0 to 3.5 and a standard deviation of the yarn cross-sectional profile of 0.01 to 1.0 is in the form of peanuts.

The polyurethane-urea elastic yarn of the present invention has the above-mentioned physical properties, so that it has excellent marine properties without causing a phenomenon such as yarn flow or band formation during knitting with a mating yarn (nylon, cotton, silk, wool, etc.) And the like.

Hereinafter, the present invention will be described concretely with reference to Examples. However, the following Examples and Experimental Examples are merely illustrative of one form of the present invention, and the scope of the present invention is not limited by the following Examples and Experimental Examples .

Example  One

Was prepared using 4,4'-diphenylmethane diisocyanate and polytetramethylene ether glycol (molecular weight 1800) such that the NCO% of the polyurethane prepolymer was 2.75%. As the chain extender, 100 mol% of ethylenediamine was used, and diethylamine was used as a chain termination agent. The ratio of the chain extender and the solvent was set at 10: 1, and the amine used was made to a total concentration of 7 mol%. Dimethylacetamide was used as the solvent, and polyurethaneurea having a solid content of 35 wt% A spinning solution was obtained.

1.5 wt% of ethylene bis (oxyethylene) bis- (3- (5-t-butyl-4-hydroxy-m-tolyl) -propionate) as an additive to the solids content of the polymer, 5,7- 0.5% by weight of 1,1,1 ', 1'-tetramethyl-4,4'- (methylene-di-p-butyl) -3- (3,4-dimethylphenyl) 1% by weight of poly (N, N-diethyl-2-aminoethyl methacrylate) and 0.1% by weight of titanium dioxide were added and mixed to obtain a polyurethane urea spinning stock solution.

The spinning solution obtained as described above was dry-spun at a temperature of 260 캜 at a rate of 1,000 m / min to prepare a polyurethane-urea elastic yarn of 20 denier 1 filaments.

Example  2

The procedure of Example 1 was repeated except that 4,4'-diphenylmethane diisocyanate and polytetramethylene ether glycol (molecular weight 1,800) were used so that the NCO% of the polyurethane prepolymer was 2.45%. The polyurethaneurea Elastic yarn was produced.

Example  3

The procedure of Example 1 was repeated except that 4,4'-diphenylmethane diisocyanate and polytetramethylene ether glycol (molecular weight 1,800) were used so that the NCO% of the polyurethane prepolymer was 2.81%. The polyurethaneurea Elastic yarn was produced.

Comparative Example  One

The procedure of Example 1 was repeated except that 4,4'-diphenylmethane diisocyanate and polytetramethylene ether glycol (molecular weight 1,800) were used so that the NCO% of the polyurethane prepolymer was 2.32%. The polyurethaneurea Elastic yarn was produced.

Comparative Example  2

4,4'-diphenylmethane diisocyanate and polytetramethylene ether glycol (molecular weight 1,800) were used so that the NCO% of the polyurethane prepolymer was 2.32%, and as the chain extender, 80 mol% of ethylene diamine and 1,2- A polyurethane-urea elastic yarn was prepared in the same manner as in Example 1, except that diaminopropane was used in an amount of 20 mol%.

Experimental Example

The physical properties of the polyurethane-urea elastic yarns prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated by the following methods, and the results are shown in Table 1 below.

(1) NCO% Calculation: NCO% = [100 * 2 * NCO chemical formula * (capping ratio-1)] / (diisocyanate molecular weight *

In the above formula, the capping ratio is the molar ratio of diisocyanate / polyol.

(2) Strength and elongation of the yarn: Measure the sample length 10 cm and tensile speed 100 cm / min using an automatic strength measuring device (MEL, Textechno). At this time, the strength and elongation at break are measured, and the modulus of 200% load applied to the yarn at 200% elongation of the yarn is also measured.

(3) Workability of knitting: A circular knitting machine was fabricated using a circular knitting machine having a diameter of 32 inches, 28 gauge, and 96 feeders using elastic yarn and nylon yarn. At this time, the nylon yarn was knitted using 70 denier, the elastic yarn 20 denier manufactured by the above, and the elastic yarn content was set to 8% with respect to the total knitted fabric weight so that the number of revolutions of the knitting machine was 5,000 counts, The thickness of the band was measured as follows.

[Figure] How to Measure Band Thickness in Librarian

(4) Method of measuring cross-sectional heterogeneity: The yarn is cut perpendicularly to the longitudinal direction, and the W and H lengths are measured with a microscope and the ratio is calculated. The closer to 1.0, the closer the cross section becomes.

Sectional Deformity = W / H

(W: longest straight line length crossing the yarn cross section, H: length of the shortest straight line perpendicularly intersecting with the longest straight line (W) of the constricted portion in the middle portion of the yarn cross section)

[Drawing] Yarn section length

NCO% EDA / 1,2PDA chain extension
(mole%) Strength (g / d) Shindo
(%) emulsion
Adhesion
(%) section
Heterogeneity
medium section
Heterogeneity
Standard Deviation Band thickness
(mm) Number of dead people
(Number of times) Example 1 2.75 100/0 1.01 478 4.5 2.87 0.50 No occurrence 0 Example 2 2.45 100/0 0.98 502 4.5 2.82 0.70 1-2 1 time Example 3 2.81 100/0 1.11 455 4.5 2.90 0.27 No occurrence 1 time Comparative Example 1 2.32 100/0 0.91 452 4.5 2.40 0.80 5 to 6 4-5 times Comparative Example 2 2.32 80/20 1.18 514 4.5 1.12 0.45 10-12 9 to 10 times

As can be seen from the above Table 1, the elastic yarn showing a peanut-shaped cross section having an NCO% of the prepolymer of 2.6 to 3.0% and a cross-sectional degree of elasticity of 2.0 to 3.5 using 100% of ethylenediamine as a chain extender was prepared The workability of knitting can be improved.

Claims (3)

Preparing a polyurethane precursor by polymerizing a polyol and a diisocyanate, and dissolving the polyurethane precursor in a solvent to prepare a prepolymer solution;
Dissolving the chain extender and the chain extender in a solvent to prepare an amine solution;
Stirring and chain extending the prepolymer solution and the amine solution to prepare a polyurethane-urea spinning solution; And
And spinning and winding the polyurethane-urea spinning stock solution,
The NCO% of the prepolymer is 2.5 to 3.0%
The emulsion adhered amount is 4.5% in the spinning step,
The chain extender is 100% ethylenediamine,
(W / H, W: length of the longest crossing yarn cross section), which is the ratio of the width (W) to length (H) Length of the shortest straight line intersecting perpendicularly with the longest straight line W of the constricted portion in the center portion of the yarn cross-section) is 2.0 to 3.5,

Wherein the standard deviation of the cross-sectional profile showing the uniformity of the yarn thickness is 0.01 to 1.0. delete A process for producing a compound of formula (I) according to claim 1,
(W / H, W: length of the longest crossing yarn cross section), which is the ratio of the width (W) to length (H) Length of the shortest straight line intersecting perpendicularly with the longest straight line W of the constricted portion in the center portion of the yarn cross-section) is 2.0 to 3.5,

Wherein the standard deviation of the cross-sectional profile showing the uniformity of the yarn thickness is 0.01 to 1.0.