KR20230152203A - Elastic fiber having improved heat setting property and method of manufacturing the same - Google Patents

Abstract

The present invention is a polyurethane-urea elastic yarn containing polyurethane-urea, which is a reaction product of a prepolymer and a chain extender. The prepolymer has a number average molecular weight (Mn) of 1000 to 5000, a functional group of 1.7 to 2.0, and CPR (Controlled). According to the present invention, the present invention relates to a polyurethane-urea elastic yarn with excellent heat-set properties, which is characterized by comprising a reaction product of diisocyanate and a polyol mixed with polypropylene glycol having a polymerization rate of -2.0 to 1.0, and a method for producing the same. Not only can the heat-set properties of polyurethane-urea elastic yarns be improved, but also the heat-set properties of fabrics knitted with polyurethane-urea elastic yarns can also be improved. In addition, the present invention can produce polyurethane-urea elastic yarn with excellent heat setting properties with excellent spinnability and productivity.

Description

Polyurethane urea elastic yarn with improved heat setting property and method of manufacturing the same {Elastic fiber having improved heat setting property and method of manufacturing the same}

The present invention relates to a polyurethane-urea elastic yarn with excellent heat-set properties and a method for manufacturing the same. More specifically, it provides a polyurethane-urea elastic yarn with excellent heat-set properties, spinnability and productivity, and a method for manufacturing the same.

Polyurethane-urea elastic yarn is widely used in elastic clothing, such as stockings, innerwear, and sportswear, sanitary products, as well as various industrial materials due to its excellent elasticity and recovery properties.

In general, polyurethane urea is obtained by reacting polyol with an excess of diisocyanate compound to obtain a prepolymer, and the prepolymer is subjected to an appropriate reaction to create a spinning solution of polyurethane urea fiber and then spun to obtain elastic yarn.

Polyurethane-urea elastic yarn is used in combination with various other fibers such as cotton, acrylic, wool, silk, etc. depending on the purpose, and especially for sports or innerwear, it is often blended with cellulose fibers such as cotton.

In general, polyurethane elastic yarn is knitted with counterpart yarns such as cotton, nylon, polyester, etc., and then subjected to a heat setting process to provide a fabric with good dimensional stability without curling due to its elastic properties. do. Typical heat setting temperatures used in commercial operations are 180°C for cotton and 190°C to 195°C for nylon. The higher the heat setting temperature, the worse the touch of the fabric containing polyurethane urea elastic yarn may occur. The higher the heat setting temperature, the higher the energy cost of the heat setting process, which reduces productivity.

KR 2008-0077126 A US 2007-0117953 A

The present invention is intended to solve the problems of the prior art described above, and one object of the present invention is to provide a polyurethane-urea elastic yarn that has excellent heat-set properties and improved touch feeling of the fabric.

Another object of the present invention is to provide a method for manufacturing polyurethane-urea elastic yarn that can improve productivity by lowering the energy cost of the heat set process.

One aspect of the present invention to achieve the above-described object is,

A polyurethane-urea elastic yarn containing polyurethane-urea, which is a reaction product of a prepolymer and a chain extender, wherein the prepolymer has a number average molecular weight (Mn) of 1000 to 5000, a functional group of 1.7 to 2.0, and a CPR (Controlled Polymerization Rate) It relates to a polyurethane-urea elastic yarn with excellent heat-set properties, characterized in that it contains a reaction product of diisocyanate and a polyol mixed with -2.0 to 1.0 polypropylene glycol.

In the present invention, the polyol may be one or more polyols selected from the group consisting of polycarbonate-based glycol, polyester-based glycol, polyether-based glycol, and combinations thereof. Preferably, the polyol may be polytetramethylene ether glycol.

The polyurethane-urea elastic yarn of the present invention may contain 3.0 to 50.0 mol% of the polypropylene glycol relative to the total polyol.

The polyurethane-urea elastic yarn of the present invention has a heat set property in the range of 55 to 80%.

Another aspect of the present invention to achieve the above-described object is,

In the step of producing a prepolymer of polyurethane-urea elastic yarn, polypropylene glycol with a number average molecular weight (Mn) of 1000 to 5000, a functional group of 1.7 to 2.0, and a CPR (Controlled Polymerization Rate) of -2.0 to 1.0 is added to the polyol. It relates to a method for manufacturing polyurethane-urea elastic yarn with excellent heat-set properties.

The polyol may be polytetramethylene ether glycol, and the polypropylene glycol may be mixed in an amount of 3.0 to 50.0 mol% based on the total polyol.

Another aspect of the present invention for achieving the above-mentioned object relates to a fabric with improved heat-set properties manufactured by knitting the polyurethane-urea elastic yarn and hard yarn of the present invention described above.

The hard yarn is selected from the group consisting of cotton, wool, linen, silk, polyester, nylon, olefin, and combinations thereof.

According to the present invention, by manufacturing a polyurethane-urea elastic yarn with improved heat setting properties, heat setting is possible at a low temperature after knitting fabric using the polyurethane-urea elastic yarn, thereby reducing heat damage to the counterpart yarn (e.g., cotton). This can improve the texture or feel of the finished fabric.

In addition, according to the present invention, the solubility of the polyurethane-urea polymer in the solvent is improved, so the solid content can be increased, and thus the drying efficiency during spinning can be improved, resulting in excellent spinnability.

In addition, according to the present invention, the energy cost of the heat setting process can be reduced to improve productivity in the production of polyurethane-urea elastic yarn and elastic fabric.

Hereinafter, the present invention will be described in more detail.

In this specification, 'including' a certain component means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

As used herein, the term “polyurethane-urea elastic yarn” refers to a synthetic fiber in which the fiber-forming material is a long-chain synthetic polymer composed of at least 85% by weight of segmented polyurethane or polyurethane-urea. As used herein, the terms “polyurethaneurea elastic yarn” and spandex are used interchangeably.

One aspect of the present invention relates to a polyurethane-urea elastic yarn with excellent heat-set properties comprising polyurethane-urea, which is a reaction product of a prepolymer and a chain extender, wherein the prepolymer has a number average molecular weight (Mn) of 1000 to 5000. , a functional group (functionality) of 1.7 to 2.0 (including boundary values), and a CPR (controlled polymerization rate) of -2.0 to 1.0. It is characterized in that it contains a reaction product of polyol and diisocyanate mixed with polypropylene glycol.

Compared to polytetramethylene ether glycol (PTMG), which has a linear chemical structure of four carbon elements, polypropylene glycol has one of the three carbon elements in the form of a side branch, so when polypropylene glycol is applied to polymerize polyurethane-urea polymer. It forms a bulky structure and has the effect of improving heat setting properties.

The polypropylene glycol used in the present invention must have a functionality of 1.7 to 2.0 and a controlled polymerization rate (CPR) of -2.0 to 1.0.

In the present invention, the functionality of polypropylene glycol can be obtained from the following formula.

[Formula 1]

Number of functional groups = (Number of moles of -OH terminal of polypropylene glycol)/(Number of moles of terminal of polypropylene glycol/2)

※ The case where both terminals of polypropylene glycol are -OH is set to 2.

If the number of functional groups of polypropylene glycol is less than 1.7, unreacted diisocyanate is generated during the primary polymerization of polyurethane-urea elastic yarn, resulting in the production of many short prepolymers and low reactivity, which takes a long time to apply to the process. There is a difficult problem. On the other hand, when the CPR of polypropylene glycol is less than -2.0 or more than 1.0, during the primary polymerization of polyurethane-urea elastic yarn, non-uniformity of polymerization occurs, making it difficult to control the polymerization process.

In the present invention, it is preferable to mix 3.0 to 50.0 mol% of polypropylene glycol based on the total polyol. If less than 3.0 mol% of polypropylene glycol is applied, improvement in the heat setting properties of polyurethane urea elastic yarn cannot be expected, and if it is applied in excess of 50.0 mol%, the physical properties of the elastic yarn will be seriously deteriorated and spinning will occur due to its too bulky chemical structure. Since mid-orientation crystallization does not occur, the process may be impossible to apply due to poor spinning workability.

The number average molecular weight of polypropylene glycol used in the present invention is preferably 1,000 or more and 5,000 or less. If the number average molecular weight of polypropylene glycol is less than 1,000, the spinning workability is insufficient due to the decrease in elongation of the polyurethane urea elastic yarn, and if it is more than 5000, the melting point is high and the storage stability of the polymer is insufficient, making process application difficult.

The polyol is preferably at least one polyol selected from the group consisting of polycarbonate-based glycol, polyester-based glycol, polyether-based glycol, and combinations thereof. In particular, polyether glycol is preferred from the viewpoint of providing flexibility and elongation to the elastic yarn. Examples of polyether glycols include polyethylene oxide, polyethylene glycol, polyethylene glycol derivatives, polypropylene glycol, polytetramethylene ether glycol (PTMG), modified PTMG (3M-PTMG), a copolymer of THF and 3-MeTHF, and THF. and modified PTMG, which is a copolymer of 2,3-dimethylTHF, are preferably used. Preferably the polyether-based polyol is polytetramethylene ether glycol. These polyether glycols may be used one type, or two or more types may be mixed or copolymerized.

The polyurethane-urea elastic yarn of the present invention may have a heat set property of 55 to 80% obtained by the following formula.

[formula]

Heat setability (%) = {(length after dry heat treatment and wet heat treatment - initial length)/(elongation length - initial length)}×100

(In the above formula, the elongation length is the length when the yarn is stretched 100% in the air, and the length after dry heat treatment and wet heat treatment is dry heat treatment at 190°C for 1 minute, cooled to room temperature, and then wet heat treatment in water at 100°C for 30 minutes. It is the length of time)

The diisocyanate used in the present invention is one or two or more organic diisocyanates selected from aromatic, aliphatic, and cycloaliphatic diisocyanates, such as 4,4'-dithenylmethane diisocyanate, 2,4'-diphenylmethanedi. Isocyanate, 1,5'-naphthalene diisocyanate, 1,4'-phenylene diisocyanate, hexamethylene diisocyanate, 1,4'-cyclohexane diisocyanate, 4,4'-dicyclohexyl methanedisocyanate, isophorone diisocyanate Isocyanate, etc.

Diamines can be used as chain extenders used to chain extend the prepolymer. Examples of such diamines include hydrazine, ethylenediamine, 1,2-propane diamine, 1,3-propane diamine, and 1,2-butanediamine (1 ,2-diaminobutane), 1,3-butanediamine (1,3-diaminobutane), 1,4-butanediamine (1,4-diaminobutane), 1,3-diamino 2,2- Dimethylbutane, 4,4'-methylene-bis-cyclohexyl amine, 1-amino-3,3,5-trimethyl-5-aminomethyl cyclohexane, 1,6-hexanediamine, 2,2-dimethyl1,3 -Diaminopropane, 2,4-diamino 1-methyl cyclohexane, N-methyl aminobis (3-propyl amine), 2-methyl-1,5-pentane diamine, 1,5-diaminopentane, 1, 4-cyclohexane diamine, 1,3-diamino4-methyl cyclohexane, 1,3-cyclohexane-diamine, 1, 1-methylene bis(4,4'-diaminohexane), 3-aminomethyl-3 , 5,5-trimethyl cyclohexane, 1,3-pentane diamine (1,3-diaminopentane), m-xylene diamine, and mixtures thereof, but are not necessarily limited to these.

In the present invention, chain terminators are generally used in chain extension reactions to control the molecular weight of polyurethane. Any chain terminator known in the art may be used. Examples of chain terminators include diethylamine (DEA), cyclohexylamine, butylamine, hexanol, butanol, and mixtures of two or more of these.

Solvents for improving radioactivity by controlling the solid concentration of the polymer include diethylacetamide, dimethylformamide, hexamethylphosphoformamide, dimethylnitrosoamine, dimethylpropionamide, methoxydimethylacetamide, and N-methylpyrrolidine. There are compounds such as , dimethyl sulfoxide, and tetramethylene sulfone, and dimethylformamide or dimethylacetamide is advantageous in terms of compatibility with polymers, radioactivity, and solvent recovery.

In addition, in the present invention, in order to prevent discoloration and deterioration of physical properties of polyurethane urea due to ultraviolet rays, atmospheric smog, and heat treatment process accompanying spandex processing, sterically hindered phenolic compounds, benzofuran-based compounds, and semicarbazide are added to the spinning solution. -based compounds, benzotriazole-based compounds, polymeric tertiary amine stabilizers, etc. can be added in appropriate combination. In addition to the above components, the polyurethane-urea elastic yarn of the present invention may contain additives such as titanium dioxide, magnesium stearate, etc.

In addition, the molecular weight of the polyurethane-urea elastic yarn of the present invention is preferably in the range of 40,000 to 150,000 as a number average molecular weight from the viewpoint of obtaining fibers with high durability and strength.

The polyurethane-urea elastic yarn may be used alone, or may be covered, braided, or mixed with any other counterpart. Counterfibres include, but are not necessarily limited to, nylon, polyester, cotton, wool, jute, hemp, flax, bamboo, polypropylene, polyethylene, rayon, any type of cellulosic fiber, and acrylic fiber. .

Another aspect of the present invention is that in the step of preparing a prepolymer of polyurethane-urea elastic yarn, the polyol has a number average molecular weight (Mn) of 1000 to 5000, a functional group number of 1.7 to 2.0, and a CPR (Controlled Polymerization Rate) of -2.0 to 1.0. It relates to a method for manufacturing polyurethane-urea elastic yarn with excellent heat setting properties, characterized by adding polypropylene glycol.

In the present invention, a prepolymer is prepared by mixing poly(tetramethylene ether) glycol and polypropylene glycol and then performing primary polymerization with at least one organic diisocyanate selected from aromatic, aliphatic, and cycloaliphatic diisocyanates, which is then prepared as an organic After dissolving in a solvent, a chain extender and a chain termination agent are added to perform secondary polymerization to prepare a spinning stock solution. At this time, the chain extender and chain termination agent may be added all at once or in two or more steps.

Next, the spinning solution is dry or wet spun to produce polyurethane-urea elastic yarn.

The polypropylene glycol used in the present invention has a functional group number of 1.7 to 2.0, and a CPR (Controlled Polymerization Rate) must be within the range of -2.0 to 1.0 to be used without problems in polymerizing polyurethane-urea for spandex. If the number of functional groups of polypropylene glycol is less than 1.7, unreacted diisocyanate is generated during the primary polymerization of polyurethane-urea elastic yarn, resulting in the production of many short prepolymers and low reactivity, which takes a long time to apply in the process. There is a problem that is difficult to solve. Also, if the CPR of polypropylene glycol is less than -2.0 or more than 1.0, there is a problem in that it is difficult to control the polymerization process due to non-uniformity of polymerization during the primary polymerization of polyurethane-urea elastic yarn.

The polypropylene glycol can be mixed in an amount of 3.0 to 50.0 mol% based on the total polyol.

In the process of dissolving spandex polymerization solids in an organic solvent and then obtaining spandex yarn through dry or wet spinning, applying polypropylene glycol improves the solubility of the polymer in the organic solvent due to its bulky chemical structure, resulting in spandex polymerization. The solid content can be increased. Drying efficiency during dry or wet spinning can be increased by increasing the spandex solid content.

Another aspect of the present invention relates to a fabric with improved heat set properties manufactured by knitting the polyurethane-urea elastic yarn and hard yarn of the present invention described above.

The hard yarn may be selected from the group consisting of cotton, wool, linen, silk, polyester, nylon, olefin, and combinations thereof, but is not necessarily limited thereto.

Hereinafter, the present invention will be described in detail through examples. The following examples are provided for illustrative purposes and are not intended to limit the invention in any way.

<Synthesis of polypropylene glycol>

Example 1

After mixing 87.3 kg of polytetramethylene ether glycol (PTMG, molecular weight 1800) with 3.0 mol% (3.0 kg) of polypropylene glycol (PPG-2000D, manufactured by Kumho Petrochemical Co., Ltd., molecular weight 2000, number of functional groups 2.0, CPR 0.4), 4 , 21.3 kg of 4'-diphenylmethane diisocyanate was added and reacted in a nitrogen gas stream at 90°C with stirring for 120 minutes to prepare a polyurethane prepolymer with isocyanate at both ends. After cooling the prepolymer to room temperature, 179.9 kg of dimethylacetamide was added as a solvent to obtain a polyurethane prepolymer solution.

Next, 2.2 kg of ethylenediamine as a chain extender and 0.2 kg of diethylamine as a chain terminator were dissolved in 31.8 kg of dimethylacetamide and added to the prepolymer solution at 10°C or lower to prepare a polyurethane-urea solution with a solid content of 35% by weight. got it At this time, 1.0% by weight of triethylene glycol-bis-3-(3-tertiarybutyl-4-hydroxy-5-methylphenyl)propionate as an antioxidant and melamine polyphosphate 1 as an inorganic chlorine agent were added to the polyurethane-urea solution. A polyurethane-urea spinning stock solution was prepared by mixing 2% by weight of coated hydrotalcite (Mg ₄ Al ₂ (OH) ₁₂ CO ₃ ·3H ₂ O) and 0.1% by weight of titanium dioxide as a light stopper.

The spinning stock solution obtained as above was spun by dry spinning at a speed of 900 m/min to produce polyurethane-urea elastic yarn of 40 denier 3 filaments.

Example 2

During the process of preparing the prepolymer of Example 1, 15.0 mol% (15.0 kg) of polypropylene glycol (molecular weight 2000, number of functional groups 2.0, CPR 0.4) was mixed with 76.5 kg of polytetramethylene ether glycol (PTMG, molecular weight 1800). Then, 21.3 kg of 4,4'-diphenylmethane diisocyanate was added and reacted in a nitrogen gas stream at 90°C with stirring for 120 minutes to prepare a polyurethane prepolymer with isocyanate at both ends. Polyurethane-urea elastic yarn was manufactured in the same manner as in 1.

Example 3

During the process of preparing the prepolymer of Example 1, 25.0 mol% (25.0 kg) of polypropylene glycol (molecular weight 2000, number of functional groups 2.0, CPR 0.4) was mixed with 67.5 kg of polytetramethylene ether glycol (PTMG, molecular weight 1800). Then, 21.3 kg of 4,4'-diphenylmethane diisocyanate was added and reacted in a nitrogen gas stream at 90°C with stirring for 120 minutes to prepare a polyurethane prepolymer with isocyanate at both ends. Polyurethane-urea elastic yarn was manufactured in the same manner as in 1.

Example 4

During the process of preparing the prepolymer of Example 1, 50.0 mol% (50.0 kg) of polypropylene glycol (molecular weight 2000, number of functional groups 2.0, CPR 0.4) was mixed with 45.0 kg of polytetramethylene ether glycol (PTMG, molecular weight 1800). After that, 21.3 kg of 4,4'-diphenylmethane diisocyanate was added and reacted in a nitrogen gas stream at 90°C with stirring for 120 minutes to prepare a polyurethane prepolymer with isocyanate at both ends. Polyurethane-urea elastic yarn was manufactured in the same manner as in Example 1.

Comparative Example 1

During the process of preparing the prepolymer of Example 1, 21.3 kg of 4,4'-diphenylmethane diisocyanate was added to 90.0 kg of polytetramethylene ether glycol (PTMG, molecular weight 1800), and the mixture was heated at 90° C. and 120° C. in a nitrogen gas stream. Polyurethane-urea elastic yarn was prepared in the same manner as in Example 1, except that the reaction was performed while stirring for a minute to prepare a polyurethane prepolymer with isocyanate at both ends.

Comparative Example 2

During the process of preparing the prepolymer of Example 1, 2.0 mol% (2.0 kg) of polypropylene glycol (molecular weight 2000, number of functional groups 2.0, CPR 0.4) was mixed with 88.2 kg of polytetramethylene ether glycol (PTMG, molecular weight 1800). Then, 21.3 kg of 4,4'-diphenylmethane diisocyanate was added and reacted in a nitrogen gas stream at 90°C with stirring for 120 minutes to prepare a polyurethane prepolymer with isocyanate at both ends. Polyurethane-urea elastic yarn was manufactured in the same manner as in 1.

Comparative Example 3

During the process of preparing the prepolymer of Example 1, 51.0 mol% (51.0 kg) of polypropylene glycol (molecular weight 2000, number of functional groups 2.0, CPR 0.4) was mixed with 44.1 kg of polytetramethylene ether glycol (PTMG, molecular weight 1800). Then, 21.3 kg of 4,4'-diphenylmethane diisocyanate was added and reacted in a nitrogen gas stream at 90°C with stirring for 120 minutes to prepare a polyurethane prepolymer with isocyanate at both ends. Polyurethane-urea elastic yarn was manufactured in the same manner as in 1.

Examples 5-6 and Comparative Examples 4-5

In Example 5-6 and Comparative Example 4-5, polyurethane elastic yarn was manufactured in the same manner as in Example 1, except that the number of functional groups of polypropylene glycol was changed as shown in Table 1 below, and then prepared in the same manner. The physical properties were evaluated and the results are shown in Table 1 below.

Example 7-8 and Comparative Example 6-7

In Examples 6 to 7 and Comparative Examples 5 to 6, polyurethane elastic yarn was manufactured in the same manner as in Example 1 except that the CPR of polypropylene glycol was changed as shown in Table 1 below, and then the physical properties were measured in the same manner. was evaluated and the results are shown in Table 1 below.

Experiment example

The polyurethane-urea elastic yarns obtained in the above-described Examples 1-8 and Comparative Examples 1-7 were evaluated for heat-set properties, elongation, spinning workability, and fabric touch, and the results are shown in Table 1 below.

* Heat setting properties of yarn

The produced yarn was stretched to 100% while exposed to the air and then subjected to dry heat treatment at 190°C for 1 minute. Afterwards, it was cooled to room temperature and then subjected to moist heat treatment in water at 100°C for 30 minutes. Afterwards, the length of the yarn was measured and the heat set property of the yarn was calculated according to the formula below.

[formula]

Heat setability (%) = {(length after dry heat treatment and wet heat treatment-initial length)/(elongation length-initial length)}×100

(In the above formula, the elongation length is the length when the yarn is stretched 100% in the air, and the length after dry heat treatment and wet heat treatment is dry heat treatment at 190°C for 1 minute, cooled to room temperature, and then wet heat treatment in water at 100°C for 30 minutes. It is the length of time)

* Strength and elongation of yarn

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

* Radiation workability

Spinning workability refers to the ratio of the amount of good yarn excluding defective products to the total amount of yarn produced per day. Higher workability means that good yarn is produced without defects such as thread cutting or plying.

* Fabric touch

The touch of the fabric was determined by the evaluator's visual and tactile senses through sensory evaluation.

division PPG
content
(mole%) PPG
Molecular Weight PPG
number of functional groups PPG CPR Heat setting property believer Max DR robbery The touch of the fabric Spinning workability Example 1 3 2000 2.0 0.4 55% 488 4.7 1.20 Great Good Example 2 15 2000 2.0 0.4 60% 500 4.8 1.11 Great Good Example 3 25 2000 2.0 0.4 65% 508 4.9 1.08 Great Good Example 4 50 2000 2.0 0.4 80% 517 5.0 1.01 Great Good Example 5 3 2000 1.9 0.4 55% 487 4.7 1.19 Great Good Example 6 3 2000 2.0 1.0 55% 488 4.7 1.20 Great Good Example 7 3 2000 2.0 -2.0 55% 489 4.7 1.19 Great Good Comparative Example 1 0 - - - 50% 470 4.5 1.25 error Good Comparative example 2 2 2000 2.0 0.4 51% 476 4.5 1.23 error Good Comparative Example 3 51 2000 2.0 0.4 81% 520 5.0 1.00 Great error Comparative Example 4 3 2000 1.6 0.4 - - - - - - Comparative Example 5 3 2000 2.0 1.1 - - - - - - Comparative Example 6 3 2000 2.0 -2.1 - - - - - -

From the experimental results in Table 1 above, it was confirmed that the heat setting properties of the yarn in the examples according to the present invention were superior to the comparative examples. In the case of Comparative Example 2, when 2 mol% of polypropylene glycol is applied, the effect of improving the heat setting property of the yarn is only 1% compared to the content without polypropylene glycol, which is minimal, and in Comparative Example 3, the effect of improving the heat setting property of the yarn is 1% compared to the content without polypropylene glycol. It can be seen that the process application is difficult due to poor workability during spinning due to excessive addition.

In Comparative Examples 4 to 6, polymerization was difficult and elastic yarns could not be manufactured, so physical properties could not be measured. Referring to Comparative Example 4, when the number of functional groups of polypropylene glycol is less than 1.7, a large number of short prepolymers are generated due to the generation of unreacted diisocyanate, and the reaction time is long due to low reactivity, making it difficult to apply it to the process. There is a difficult problem, and in cases where the CPR of polypropylene glycol is less than -2.0 or more than 1.0, as in Comparative Example 5 or Comparative Example 6, non-uniformity occurs during the primary polymerization of polyurethane urea for spandex, making polymerization control difficult. A problem arises that is difficult to solve.

Although the present invention has been described in detail above using specific examples, these are for illustrative purposes. Various forms of substitution, modification, and change may be made by those skilled in the art without departing from the technical spirit of the present invention, and the scope of protection of the present invention includes all such modifications and changes. It is intended.

Claims (10)

A polyurethane-urea elastic yarn containing polyurethane-urea, which is a reaction product of a prepolymer and a chain extender, wherein the prepolymer has a number average molecular weight (Mn) of 1000 to 5000, a functional group of 1.7 to 2.0, and a CPR (Controlled Polymerization Rate) A polyurethane-urea elastic yarn with excellent heat set properties, comprising a reaction product of a polyol containing 3.0 to 50.0 mol% of -2.0 to 1.0 polypropylene glycol relative to the total polyol and diisocyanate.
The method according to claim 1, wherein the polyol containing polypropylene glycol is a heat-set property, characterized in that at least one polyol selected from the group consisting of polycarbonate-based glycol, polyester-based glycol, polyether-based glycol, and combinations thereof. This excellent polyurethane urea elastic yarn.
The polyurethane-urea elastic yarn with excellent heat setting property according to claim 2, wherein the polyether glycol is polytetramethylene ether glycol.
The polyurethane-urea elastic yarn according to claim 1, wherein the polypropylene glycol has a number average molecular weight (Mn) of 1000 to 5000.
The polyurethane-urea elastic yarn with excellent heat-set property according to claim 1, wherein the heat-set property of the polyurethane-urea elastic yarn calculated by the following formula is 55 to 80%.
[formula]
Heat setability (%) = {(length after dry heat treatment and wet heat treatment - initial length)/(elongation length - initial length)}×100
(In the above equation, the elongation length is the length when the yarn is stretched 100% in the air, and the length after dry heat treatment and wet heat treatment is dry heat treatment at 190°C for 1 minute, cooled to room temperature, and then wet heat treatment in water at 100°C for 30 minutes. It is the length of time)
In the step of producing a prepolymer of polyurethane-urea elastic yarn, polypropylene glycol with a number average molecular weight (Mn) of 1000 to 5000, a functional group of 1.7 to 2.0, and a CPR (Controlled Polymerization Rate) of -2.0 to 1.0 is added to the polyol. A method for manufacturing polyurethane-urea elastic yarn with excellent heat-set properties.
The method of claim 6, wherein the polypropylene glycol is mixed in an amount of 3.0 to 50.0 mol% based on the total polyol.
The method of claim 6, wherein the polyol containing polypropylene glycol is polytetramethylene ether glycol.
A fabric with excellent heat set properties manufactured by knitting the polyurethane urea elastic yarn and hard yarn of claim 1.
The fabric according to claim 9, wherein the hard yarn is selected from the group consisting of cotton, wool, linen, silk, polyester, nylon, olefin, and combinations thereof.