KR100615780B1 - Spandex fiber having a high tension maintenance - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spandex fiber having a high stress retention rate. A polyurethaneurea elastic yarn polymer prepared by reacting an organic diisocyanate with a polymer diol to prepare a polyurethane precursor, dissolving it in an organic solvent, and then reacting with a diamine and / or a monoamine. In the polyurethane urea polymer, characterized in that it comprises a polymer triol so that the molar ratio of the polymer diol and the polymer triol is 99: 1 to 70:30 based on the polymer diol. More specifically, the present invention relates to a spandex fiber having high stress retention by introducing polymer triols such as polyethylene triol, polypropylene triol and polytetramethylene triol into the molecular chain to cause slight crosslinking. Polyurethane urea elastic yarn according to the present invention can maintain a good resilience even in repeated elongation when applied to the product because it has a high level of stress retention without high adhesion.

Polyurethane Urea Elastic Yarn, Stress, Polymer Triol

Description

SPANDEX FIBER HAVING A HIGH TENSION MAINTENANCE}

The present invention relates to a spandex fiber having a high stress retention rate, and more particularly, polymer triols such as polyethylene triol, polypropylene triol and polytetramethylene triol are introduced into the molecular chain to cause slight crosslinking. The present invention relates to a spandex fiber having a stress retention rate.

In general, spandex fibers are widely known as highly stretchable polyurethane fibers having a urethane bond of 85% by weight or more. Spandex fibers generally include a spinning yarn which extrudes a spinning solution containing polyurethane through a nozzle and introduces a heating gas for evaporating and drying the solvent; Wet spinning to solidify the polymer while eluting the solvent through a spinning bath; Chemical spinning for extending the chain reaction by extruding a prepolymer solution having an isocyanate through a nozzle in a reaction solution containing an amine chain extender; Or melt spinning for extruding and cooling the polyurethane through a nozzle in a molten state of heating;

It is very important that the spandex fiber has a high level of stress retention when it is repeatedly stretched and shrunk. In the conventional art of this field, instead of using 100% polytetramethylene glycol as a polymer diol, The technique which raises a stress retention rate by using the polytetramethylene glycol of the copolymer form containing a methyl methyl tetrahydrofuran and a neopentyl group at a part is mentioned.

For example, US Pat. No. 5,000,899 describes the preparation of soft segments using copolymers of 3-methyltetrahydrofuran and tetrahydrofuran, followed by the preparation of spandex using ethylenediamine, 2-methylpentamethylenediamine as chain extenders. Here's how.

However, when the spandex is manufactured by such a conventional method, the prepared spandex has high adhesiveness, which causes many problems in process and products. For example, workability at the time of dry spinning is lowered, and adhesiveness occurs during storage due to high interadhesion, which may cause problems in the maritime process.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a spandex fiber to have a high level of stress retention while not having a high adhesion.

The object of the present invention as described above, in the polyurethane urea elastic yarn polymer prepared by reacting organic diisocyanate with a polymer diol to prepare a polyurethane precursor, and then dissolve it in an organic solvent and reacted with diamine and / or monoamine, The polyurethaneurea polymer is achieved by a spandex fiber comprising a polymer triol such that the molar ratio of the polymer diol and the polymer triol is 99: 1 to 70:30 based on the polymer diol.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description of the invention and the preferred embodiments.

Hereinafter, the structure of the spandex fiber with high stress retention according to the present invention will be described.

The spandex fiber of the present invention is such that the molar ratio of the polymer diol and the polymer triol (A) included in the segmented polyurethane polymer is from 99: 1 to 70:30.

The segmented polyurethane polymers used in the spandex fibers of the present invention react with organic diisocyanates and polymer diols to prepare polyurethane precursors, and then dissolve them in organic solvents and then react with diamines and monoamines, as known in the art. It is prepared by making.

The organic diisocyanate used in the present invention includes diphenylmethane-4,4 'diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, butylene diisocyanate, hydrogenated P, P-methylene diisocyanate and the like. As the polymer diol, polytetramethylene ether glycol, polypropylene glycol, polycarbonate diol, and the like may be used. The diamines are used as chain extenders, and examples thereof include ethylenediamine, propylenediamine, hydrazine, and the like. In addition, the monoamine is used as a chain terminator, and examples thereof include diethylamine, monoethanolamine, dimethylamine, and the like.

(A) polymer triol

The polymer triol used in the present invention has a molecular weight of 1000 to 4000 and is characterized by using one containing three hydroxy groups in a single molecule. Polyethylenetriol, polypropylenetriol, polytetramethylenetriol and the like can be used, but are not limited to these materials. These materials serve to cause crosslinking in the reaction of organic diisocyanates with the polymeric diols to produce prepolymers. When a low molecular triol such as glycerol is used in place of the polymer triol, due to the difference in reaction rate with the polymer diol, a normal prepolymer cannot be synthesized and a gel is formed.

The polymer triol added to the spandex fiber of the present invention does not exhibit the characteristics of the present invention below a given range of content, and cannot be used as a spandex production technique by advancing abnormal reactions such as gel formation above a given range of content.

The spandex fiber of the present invention may be prepared by incorporating the polymer triol in the amount specified above in the synthesis of the segmented polyurethane polymer by a known method, followed by spinning by a conventional method.

The invention can be better understood by the following examples, the following examples are for the purpose of illustrating the invention and are not intended to limit the scope of the invention.

Example 1

Preparation of Segment Polyurethane Polymer

 200 g of diphenylmethane-4,4 'diisocyanate, 810 g of polytetramethylene ether glycol (molecular weight 1800) and polytetramethylene triol (molecular weight 3000) were added so that the molar ratio of polytetramethylene glycol was 9: 1, and nitrogen was added. The reaction was stirred at 90 ° C. for 90 minutes in a gas stream to prepare a polyurethane prepolymer having an isocyanate at the sock end. After the polyurethane precursor was cooled to room temperature, 1300 g of dimethylacetamide was added thereto and dissolved to obtain a polyurethane prepolymer solution.

18 g of ethylenediamine and 2.5 g of diethylamine were then dissolved in 780 g of dimethylacetamide and added to the prepolymer solution at 5 ° C. to obtain a segmented polyurethane solution.

Preparation of Spandex Fiber

After defoaming the solution, it was used as a spinning stock solution, and an elastic yarn of 4 filaments 40 denier was prepared by adjusting the spinning temperature to 250 ° C. in a dry spinning process. The physical properties of the elastic yarn thus obtained were measured in the following manner.

Property evaluation

Using Instron's INSTRON 5565, the gauge length was set to 2 inches and five elastic yarn long fiber samples were cycled five times between 0 and 300% at a constant drawing speed of 500 mm / min, followed by the fifth extension. The ratio of the stress at shrinkage (S2) to the stress at stretch (S1) at 200% was followed by a method of expressing the percentage of stress retention as a percentage.

Stress Retention Rate (%) = S2 / S1 × 100 ---- Formula (1)

Table 1 shows the stress retention measured as described above.

Example 2

Polyurethane elastic yarn was produced in the same manner as in Example 1 except that polytetramethylenetriol (molecular weight 3000) was added so that the molar ratio with polytetramethylene glycol was 95: 5, and then the stress retention rate was evaluated for this fiber. It is shown in Table 1.

Example 3

Polyurethane elastic yarn was prepared in the same manner as in Example 1 except that polytetramethylenetriol (molecular weight 3000) was added so that the molar ratio with polytetramethylene glycol was 85:15, and then the stress retention rate of the fiber was evaluated. It is shown in Table 1.

Comparative Example 1

Polyurethane elastic yarn was manufactured in the same manner as in Example 1 except that polytetramethylenetriol (molecular weight 3000) was added so that the molar ratio with polytetramethylene glycol was 60:40. The results are shown in Table 1.

Comparative Example 2

Polyurethane elastic yarn was prepared in the same manner as in Example 1 except that glycerol was used instead of polytetramethylenetriol (molecular weight 3000). The results are shown in Table 1.

TABLE 1

According to the spandex fiber having a high stress holding ratio according to the present invention as described above, it has a feature that can maintain excellent restoring force even when repeated as a product because it has a high level of stress retention without high adhesion.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims include such modifications and variations as fall within the spirit of the invention.

Claims (5)

In the polyurethaneurea elastic yarn polymer produced by reacting an organic diisocyanate with a polymer diol to prepare a polyurethane precursor, dissolving it in an organic solvent and then reacting with a diamine and / or a monoamine, In the polyurethaneurea polymer, a high-strength spandex fiber comprising a polymer triol such that a molar ratio of the polymer diol and the polymer triol is 99: 1 to 70:30 based on the polymer diol. The spandex fiber according to claim 1, wherein the polymer triol has a molecular weight of 1000 to 4000 and contains three hydroxy groups in a single molecule. The spandex fiber having high stress retention according to claim 1, wherein the polymer triol is selected from polyethylene triol, polypropylene triol, and polytetramethylene triol. The spandex fiber having a high stress retention rate according to claim 1, wherein the stress retention rate of the spandex fiber is 72% or more. The spandex fiber having high stress retention according to claim 1, wherein the polymer diol is polytetramethylene ether glycol, polypropylene glycol or polycarbonate diol.