WO2022005191A1 - Heat-bondable composite fiber, manufacturing method therefor, and fiber aggregate and nonwoven-fabric which comprise same - Google Patents

Abstract

The present invention relates to a heat-bondable composite fiber, a manufacturing method therefor, and a fiber aggregate and a nonwoven fabric which comprise same. More specifically, the present invention relates to: a heat-bondable composite fiber having a low process fraction defective, excellent productivity, and excellent adhesiveness and elastic recovery; a manufacturing method therefor; and a fiber aggregate and a nonwoven fabric which are harmless to the human body, and thus are suitable for a material that comes in contact with the human body.

Description

Heat-adhesive composite fiber, manufacturing method thereof, fiber aggregate and nonwoven fabric comprising the same

The present invention relates to a heat-adhesive composite fiber, a method for manufacturing the same, a fiber aggregate and a nonwoven fabric comprising the same. More specifically, it relates to a heat-adhesive composite fiber having a low process defect rate, excellent productivity, and excellent adhesiveness and elastic recovery rate and a method for manufacturing the same, and a fiber aggregate suitable for use in materials that are harmless to the human body and in contact with the human body and to a nonwoven fabric.

In general, polyurethane foam is a foam that can be prepared by mixing isocyanate and polyol together with a blowing agent, a catalyst, etc., and simultaneously proceeding with a foaming reaction and a polymerization reaction. These polyurethane foams are light and have excellent thermal insulation, electrical insulation, chemical resistance, rebound elasticity and durability, and are therefore widely used as elastic materials in the cushion material field. However, polyurethane foam has problems in use such as yellowing and odor, environmental hazards, and deterioration of physical properties.

On the other hand, in addition to polyurethane foam, a fiber aggregate fused with eco-friendly heat-sealing fibers that are harmless to the human body is also used as an elastic material. Elastomers used as fiber aggregate materials are used in many applications such as packaging containers, automobile interior materials, and elastic fibers due to their unique elasticity. In addition, unlike rubber materials that cannot be recycled, such elastomers are easily recyclable, so the demand for them is greatly increasing. In particular, in the case of a thermoplastic polyester copolymer, it is used as a fiber aggregate material due to its excellent elasticity.

Thermoplastic elastomer (TPE) is a polymer that possesses two different properties: a thermoplastic that can be re-formed when heated and the elasticity of an elastomer, a rubbery polymer. Thermoplastic elastomer is a kind of block copolymer, and is generally composed of a hard segment block that can exhibit thermoplastic characteristics and a soft segment block that can exhibit elasticity, and exhibits two different properties at the same time.

These thermoplastic elastomers are manufactured by copolymerizing an acid component such as terephthalic acid, dimethyl terephthalate, isophthalic acid and dimethyl isophthalate with a diol component such as poly(tetramethylene ether) glycol, butanediol, polyethylene glycol and ethylene glycol. However, when manufacturing a low-melting-point thermoplastic elastomer by such a polymerization method, there is a problem that equipment for storing and inputting butanediol and equipment for recovering by-products such as tetrahydrofuran are required. In particular, tetrahydrofuran is a high-risk substance with toxicity and explosiveness, and it is difficult to manage safety.

In addition, although the demand for these thermoplastic elastomers is increasing, there is a disadvantage in that the fixed cost rises when the polymer is produced by the polymerization method because the market size is not relatively large, which leads to an increase in cost.

The present invention has been devised to solve the above problems, and the problem to be solved by the present invention is a heat-adhesive composite fiber that has excellent thermal adhesiveness and elastic recovery rate and can reduce costs, and a fiber aggregate and nonwoven fabric including the same is to provide

Another object to be solved by the present invention is to provide a method for manufacturing a heat-adhesive composite fiber having a low process defect rate and excellent productivity.

In order to solve the above problems, the present invention provides a thermoplastic polyester-based elastomer resin which is a block copolymer having a melting point of 110°C to 180°C and containing a soft segment represented by the following Chemical Formula 1 in an amount of 5 to 25 mol%; And it provides a heat-adhesive composite fiber formed by composite spinning a polyester-based resin having a melting point of 230°C to 280°C.

[Formula 1]

In Formula 1, R represents a C _3-5 alkylene group.

In a preferred embodiment of the present invention, the thermoplastic polyester-based elastomer resin is a resin A comprising a compound represented by the following formula (2); and a resin B comprising at least one of a compound represented by the following Chemical Formula 3 and a compound represented by the following Chemical Formula 4; It may include a block copolymer formed through a transesterification reaction between the.

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4, P ¹ and P ² are each independently

or

, R ¹ and R ² are each independently a C ₃ to C ₅ alkylene group, R ₃ to R ₅ are each independently a C ₁ to C ₃ alkylene group, R ⁶ is C ₄ H ₈ and n is 5 to a rational number of 45, x is a rational number from 25 to 90, y is a rational number from 10 to 75, a and c are each independently a rational number from 55 to 80, and b and d are each independently a rational number from 20 to 45.

In a preferred embodiment of the present invention, the thermoplastic polyester-based elastomer resin may be formed by reacting the resin A and the resin B in a weight ratio of 7:3 to 2:8.

In a preferred embodiment of the present invention, the resin A may have a melting point of 140 °C to 175 °C, and the resin B may have a softening point of 110 °C to 150 °C.

In a preferred embodiment of the present invention, the thermoplastic polyester-based elastomer resin may be 80% to 99% measured according to ASTM D638 standard measurement method.

In addition, in order to solve the above problems, the present invention provides a fiber assembly including the heat-adhesive composite fiber.

In a preferred embodiment of the present invention, the fiber assembly may further include polyethylene terephthalate (PET) fibers.

In a preferred embodiment of the present invention, the fiber aggregate may be one in which the detection concentrations of heavy metals antimony (Sb) and cobalt (Co) are each independently 0.1 ppm to 10 ppm.

In addition, in order to solve the above problems, the present invention provides a nonwoven fabric comprising the fiber aggregate.

In addition, in order to solve the above problems, the present invention provides (1) a resin A comprising a compound represented by the following formula (2), and at least one of a compound represented by the following formula (3) and a compound represented by the following formula (4) synthesizing a thermoplastic polyester-based elastomer resin by copolymerizing the resin B through a transesterification reaction; (2) composite spinning of the thermoplastic polyester-based elastomer resin and a polyester-based resin having a melting point of 230°C to 280°C; provides a method for producing a heat-adhesive composite fiber comprising.

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4, P ¹ and P ² are each independently

or

, R ¹ and R ² are each independently a C ₃ to C ₅ alkylene group, R ³ to R ⁵ are each independently a C ₁ to C ₃ alkylene group, R ⁶ is C ₄ H ₈ and n is 5 to a rational number of 45, x is a rational number from 25 to 90, y is a rational number from 10 to 75, a and c are each independently a rational number from 55 to 80, and b and d are each independently a rational number from 20 to 45.

The heat-adhesive composite fiber according to the present invention, a fiber aggregate and non-woven fabric comprising the same, have low thermal adhesiveness and elastic recovery rate, and are low in harmfulness to the human body. It has the advantage of being easy.

In addition, according to the method for manufacturing the heat-adhesive composite fiber according to the present invention, since no by-product is generated during manufacturing, process management is easy, the process is simplified, and thus the productivity is high, and the increase in fixed cost is minimized even in a small amount of the heat-adhesive composite fiber It has the advantage of reducing the manufacturing cost of

1 is a view schematically showing a cross-section of a heat-adhesive composite fiber according to an embodiment of the present invention.

2 is a view schematically showing a cross-section of a heat-adhesive composite fiber according to another embodiment of the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples and the accompanying drawings.

As described above, conventional heat-adhesive composite fibers generate a lot of by-products during manufacture and require a separate facility to process them, and these by-products are difficult to process, thereby increasing the manufacturing cost. Accordingly, the present inventors have disclosed a thermoplastic polyester-based elastomer resin having a melting point of 110° C. to 180° C. and including a soft segment having a structure represented by the following Chemical Formula 1 in an amount of 5 to 25 mol%; And by providing a heat-adhesive composite fiber formed by composite spinning a polyester-based resin having a melting point of 230°C to 280°C, this problem was solved.

[Formula 1]

In Formula 1, R represents a C ₃ to C ₅ alkylene group.

Preferably, n may be a rational number of 5 to 45.

Here, the meaning of including the soft segment in an amount of 5 to 25 mol% in the thermoplastic polyester-based elastomer resin means that the soft segment repeating unit including the structure represented by Formula 1 above has a content of 5 to 25 mol% compared to the total resin means that it contains

The present invention provides excellent thermal adhesion and elasticity due to the thermoplasticity of the resin by including the soft segment in an amount of 5 to 25 mol% in the thermoplastic polyester-based elastomer resin through polymer blending, and at the same time, the polyester-based elastomer has adhesiveness It has dry surface properties compared to those with sticky surface properties, so it can have improved processability. In addition, it is possible to minimize the generation of by-products during manufacturing by composite spinning between the low-melting-point polyester having a melting point of 230°C to 280°C and the polyester-based elastomer resin, and there is an advantage in that the cost can be reduced.

More preferably, the soft segment may be included in an amount of 10 to 20 mol% in the thermoplastic polyester-based elastomer.

If the content of the soft segment in the thermoplastic polyester-based elastomer resin is less than 5 mol%, there may be a problem in that sufficient elasticity is not expressed. Conversely, when the content of the soft segment exceeds 25 mol%, the surface friction of the elastomer There may be a problem that the processability is deteriorated.

Hereinafter, each configuration included in the heat-adhesive composite fiber will be described in more detail in order.

The heat-adhesive composite fiber of the present invention is prepared by composite spinning of a thermoplastic polyester-based elastomer resin and a low-melting-point polyester-based resin, and the thermoplastic polyester-based elastomer resin has a melting point of 110°C to 180°C.

Preferably, the thermoplastic polyester-based elastomer resin may have a melting point of 120°C to 165°C.

If the melting point of the thermoplastic polyester-based elastomer resin is less than 110°C, mechanical properties such as fusion, heat resistance, hardness, tensile strength and elastic modulus may be deteriorated during spinning, and the melting point of the thermoplastic polyester-based elastomer resin If it exceeds 180 ℃, there may be a problem that the thermal bonding performance is lowered or the temperature of the manufacturing process is increased during the manufacture of the fiber assembly.

The thermoplastic polyester-based elastomer resin may include a resin A comprising a compound represented by the following formula (2); And Resin B comprising at least one of the compounds represented by Formula 3 and Formula 4; It may include a block copolymer formed through a transesterification reaction between the.

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4, P ¹ and P ² are each independently

or

indicates

In addition, R ¹ and R ² may each independently represent a C ₃ to C ₆ alkylene group. Preferably, R ¹ may be a C ₃ to C ₄ alkylene group and R ² may be a C ₄ alkylene group.

In addition, R ³ to R ⁵ may each independently be a C ₁ to C ₃ alkylene group. Preferably, R ³ , R ⁴ , and R ⁵ may be a C ₂ alkylene group.

In addition, R ⁶ may be C ₄ H ₈ , and n may be a rational number of 5 to 45.

x can be a rational number from 25 to 90. Preferably, x may be 50 to 80.

y may be a rational number from 10 to 75. Preferably y may be 20 to 50, and the ratio of x and y may be preferably 2:1 to 5:1.

The segment repeated x times has a hard property, and the segment repeated y times has a soft property. When the ratio of x and y is 5:1, when x becomes larger, the molar ratio of the segment having a hard property becomes excessively large, and there may be a problem in that elasticity is insufficient. Conversely, when y is greater than 2:1 in the ratio of x and y, the molar ratio of the segment having a soft property is excessively large, and there may be a problem in that workability is deteriorated.

a and c may each independently be a rational number of 55 to 80, preferably each independently 55 to 70.

b and d may each independently be a rational number from 20 to 45, preferably from 30 to 45 each independently.

In addition, the ratio of a and b and the ratio of c and d may be preferably 1:1 to 3:1.

The segment repeated a time and the segment repeated c times have high crystallinity, and the segment repeated c times and the segment repeated d times has low crystallinity. If a and c have a ratio greater than 1:1 compared to b and d, there may be a problem in that the molar ratio of the segment having high crystallinity becomes excessively large, thereby increasing the melting point.

In addition, the resin A may preferably be an elastic polyester-based elastomer having a melting point of 140°C to 175°C. If the melting point of the resin A is less than 140 ℃, there may be a problem that the heat resistance is lowered, if the melting point exceeds 175 ℃, there may be a problem that must be thermally bonded at a high temperature.

In addition, the resin B may preferably be a low-melting polyester resin having a softening point of 110 ℃ to 150 ℃. If the softening point of Resin B is less than 110°C, there may be a problem with heat resistance, and if the softening point of Resin B exceeds 150°C, there may be a problem that thermal bonding at high temperature is required.

The thermoplastic polyester-based elastomer resin may be a block copolymer formed by reacting the resin A and the resin B in a weight ratio of 7:3 to 2:8. The weight ratio between the resin A and the resin B may be preferably 60:40 to 30:70, more preferably 50:50 to 40:60.

If the resin A has a weight ratio greater than 7:3 compared to the resin B, there is a problem in that the manufacturing cost increases. Conversely, when the resin A has a weight ratio of less than 2:8 with respect to the resin B, there may be a problem in that the elasticity of the heat-adhesive composite fiber is not sufficiently expressed.

According to a preferred embodiment, the resin A and the resin B are pyromellitic dianhydride, trimellitic dianhydride, carbonyl bis(1-caprolactam) (carbonyl bis-( 1-caprolactam)), diepoxide bisphenol A-diglycidyl ether, and diepoxide bisphenol F-diglycidyl ether (diepoxide ibsphenol F-diglycidyl ether), epoxide ( Epoxide) may be linked by a chain extender comprising at least one selected from the group consisting of, but is not limited thereto.

The chain extender is added to control the melting point and improve copolymerization efficiency in the transesterification reaction step between Resin A and Resin B, and a terminal carboxyl group or hydroxyl group of the resin represented by Chemical Formulas 2 to 4 ) and reacting.

Preferably, the chain extender may be included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic polyester-based elastomer resin. Preferably it may be included in an amount of 0.1 to 3 parts by weight, and more preferably, it can be obtained according to the following relation 1 in terms of minimizing the transesterification reaction time and gelation of the polymer.

[Relational Expression 1]

Chain extender content (wt%) = (weight average molecular weight of chain extender (M _w ) × content of the carboxyl terminus of the resin to be reacted and extruded) ÷ (2×10 ⁴ )

If the chain extender is included in an amount of less than 0.1 parts by weight, there may be a problem in that the transesterification reaction between Resin A and Resin B is too long to decrease productivity, and when included in an amount greater than 10 parts by weight, the chain is excessively Due to the extension, gelation of the polymer may occur, resulting in poor spinning operability and poor physical properties of the heat-adhesive composite fiber.

In addition, the thermoplastic polyester-based elastomer resin may include an antioxidant in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of the thermoplastic polyester-based elastomer resin for the purpose of preventing thermal decomposition and aging. The antioxidant may be at least one selected from the group consisting of a hindered phenol-based antioxidant, a diphenylamine-based antioxidant, a metal complex antioxidant, and a hindered amine-based light stabilizer, preferably tetrakismethylene (3,5-di- tert -butyl-4-hydroxyphenyl) propionate and tris(2,4-di- tert -butylphenyl)phosphite may be used alone or as a mixture of the two.

If the content of the antioxidant is less than 0.1 parts by weight, the effect of adding the antioxidant may not be sufficient, and conversely, if the content of the antioxidant exceeds 3 parts by weight, the mechanical properties of the heat-adhesive composite fiber may deteriorate. .

In addition, the thermoplastic elastomer resin may preferably have an intrinsic viscosity of 0.8 dl/g or more, preferably 0.9 dl/g to 1.5 dl/g, and more preferably 1.0 dl/g to 1.3 dl/g. If the intrinsic viscosity is less than 0.8 dl/g, there may be a problem in that spinning workability decreases.

In addition, in a preferred embodiment of the present invention, the thermoplastic polyester-based elastomer resin may have an elastic recovery rate of 85% to 99% measured according to ASTM D638 standard measurement method.

In addition, the heat-adhesive composite fiber according to the present invention is a composite fiber obtained by composite spinning a low-melting polyester-based resin having a melting point of 230°C to 280°C together with the thermoplastic polyester-based elastomer resin, and the low-melting polyester-based resin The resin is polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, polytrimethylene terephthalate (PTT) resin, and polyethylene naphthalate (PEN) resin. It may include at least one selected can do.

In addition, the low-melting polyester-based resin may have an intrinsic viscosity of 0.5 dl/g to 1.0 dl/g, preferably 0.55 dl/g to 0.90 dl/g, more preferably 0.65 dl/g to 0.75 It may have an intrinsic viscosity of dl/g. If the intrinsic viscosity of the low-melting polyester-based resin is less than 0.50 dl/g, there may be a problem in that the strength of the manufactured heat-adhesive composite fiber is lowered, and if the intrinsic viscosity exceeds 1.0 dl/g, spinning and stretching There may be a problem that the workability of the

The low melting point polyester-based resin may have a melting point of 230 °C to 280 °C, preferably 240 °C to 265 °C. If the melting point is less than 230 ℃, there may be a problem in that the stability of the fiber form during post-treatment processing. Conversely, if the melting point exceeds 280 ℃, there may be a problem in spinning workability.

The heat-adhesive composite fiber according to the present invention is a bicomponent composite fiber formed by composite spinning the thermoplastic polyester-based elastomer resin and the low-melting-point polyester-based resin, preferably side-by-side. It can be a type and a sheath-core type fiber. Specifically, FIG. 1 is a view schematically showing a cross-section of a side-by-side type composite fiber according to a preferred embodiment of the present invention, and the ratio and melt viscosity between a thermoplastic polyester-based elastomer resin and a low-melting-point polyester-based resin Accordingly, the cross-sectional shape of the composite fiber itself may vary, but the cross-sectional shape of the composite fiber is not limited.

In addition, the heat-adhesive composite fiber according to the present invention may have an average fineness of 1 denier to 15 denier, preferably 3 denier to 10 denier, and if the average fineness is less than 1 denier, spinnability and productivity are lowered as well as , there may be a problem in that the thickness of the fiber aggregate decreases due to the decrease in the spacing of the composite fibers and the increase in the bonding point, and if it exceeds 15 denier, the cross section may become non-uniform due to insufficient cooling during spinning, and adhesion during the manufacture of the fiber assembly There may be problems in that the spots are reduced and the surface uniformity of the fiber aggregate is deteriorated.

In addition, the average fiber length per filament of the heat-adhesive composite fiber according to the present invention may be 16 mm to 100 mm, preferably 24 mm to 96 mm, more preferably 32 mm to 72 mm, if the average fiber length is less than 16 mm In the fiber assembly carding process, there may be a problem that the carding workability and the morphological stability of the fiber assembly are lowered due to the lack of physical bonding of the composite fibers in the fiber assembly carding process. As a result, there may be a problem in that the surface uniformity of the fiber aggregate is lowered.

In addition, in order to solve the above problems, the present invention provides a fiber assembly including the heat-adhesive composite fiber.

In a preferred embodiment of the present invention, the fiber assembly may further include polyethylene terephthalate (PET) fibers.

In a preferred embodiment of the present invention, the fiber aggregate may be one in which the detection concentrations of heavy metals antimony (Sb) and cobalt (Co) are each independently 0.1 ppm to 10 ppm.

In general, in the process of polymerizing polyester fibers, a catalyst containing heavy metals such as antimony is used as a catalyst, and the present invention minimizes the content of heavy metals remaining in the final fiber and the fiber assembly including the same by excluding the use of the catalyst. Therefore, it is possible to provide a material suitable for use in a material in direct contact with the human body, for example, an automobile interior material, a furniture sheet, and the like.

According to a preferred embodiment of the present invention, the fiber aggregate may have a compression set of 15% or less. The compression set can be measured according to ASTM D 3574.

In addition, the polyethylene terephthalate fiber included in the fiber assembly together with the heat-adhesive composite fiber may preferably be a non-elastic polyester-based short fiber.

The mixing ratio of the heat-adhesive composite fiber and the polyethylene terephthalate fiber is 10:90 to 60:40, preferably 20:80 to 50:50, more preferably 30:70 to 50:50 days by weight. can When the ratio of the heat-adhesive composite fiber is greater than 60:40, the hardness of the fiber aggregate increases, making it difficult to apply as a material such as a mattress, and when the ratio of the heat-adhesive composite fiber is less than 10:90, the fiber aggregate is There may be a problem of reduced stability.

In addition, in order to solve the above problems, the present invention provides a nonwoven fabric comprising the fiber aggregate.

In addition, in order to solve the above problems, the present invention provides (1) a resin A comprising a compound represented by the following formula (2), and at least one of a compound represented by the following formula (3) and a compound represented by the following formula (4) synthesizing a thermoplastic polyester-based elastomer resin by copolymerizing the resin B through a transesterification reaction; (2) composite spinning of the thermoplastic polyester-based elastomer resin and a polyester-based resin having a melting point of 230°C to 280°C; provides a method for producing a heat-adhesive composite fiber comprising.

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4, P ¹ and P ² are each independently

or

, R ¹ and R ² are each independently a C ₃ to C ₅ alkylene group, R ³ to R ⁵ are each independently a C ₁ to C ₃ alkylene group, R ⁶ is C ₄ H ₈ and n is 5 to a rational number of 45, x is a rational number from 25 to 90, y is a rational number from 10 to 75, a and c are each independently a rational number from 55 to 80, and b and d are each independently a rational number from 20 to 45.

Since the types and contents of the resin used in the manufacturing method are the same as those described above, detailed descriptions thereof will be omitted below.

The transesterification reaction between the resin A and the resin B may be performed in a stationary kneader or a twin-screw kneader.

Specifically, the static kneader may be a static kneader for high shear, and the number of divisions may be 500,000 divisions to 5 million divisions, preferably 1 million divisions to 3 million divisions. If the number of divisions is less than 500,000 divisions, the copolymerization reaction is not sufficient, so it is difficult to express elastic properties, and it causes radioactive degradation due to die-swell during spinning. If it exceeds 5 million divisions, it stops Due to the pressure loss in the system kneader, there is a problem in that the spinnability is lowered because the resin cannot be discharged with equal pressure during spinning.

In a preferred embodiment of the present invention, the efficiency of the copolymerization reaction can be improved by controlling the residence time and reaction temperature of the molten resin during twin-screw kneading. If the residence time in the molten state is less than 1 minute, the reaction time is insufficient and the copolymerization reaction is insufficient, so the change in the melting point is insufficient or the expression of elastic properties is difficult, and it causes radioactive degradation due to the die swell during spinning, and the reaction time When this time exceeds 5 minutes, there is a problem in that the physical properties are lowered due to a decrease in productivity and deterioration. The reaction temperature is preferably controlled at 200°C to 270°C. If the temperature is less than 200 ℃, the reaction is too slow there is a problem that productivity is reduced, on the contrary, if the temperature exceeds 270 ℃, thermal decomposition occurs, it is difficult to obtain the desired physical properties of the fiber.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the scope of the present invention is not limited to the following examples, and those skilled in the art to which the present invention pertains can easily implement by changing the configuration of the present invention without departing from the technical spirit of the present invention. will be able

<Example>

Preparation Example 1

Polyester-based resin: A polyester-based resin was prepared by condensation polymerization of terephthalic acid as an acid component and ethylene glycol as a diol component, and condensation polymerization using a titanium-based polymerization catalyst.

The polyester-based resin prepared at this time had an intrinsic viscosity of 0.652 dl/g and a melting point of about 252°C.

Thermoplastic polyester-based elastomer: The thermoplastic polyester-based elastomer was prepared by melt-kneading Resin A, which is a compound represented by Formula 2, and Resin B, which is a compound represented by Formula 3, below. Specifically, Resin A is a commercial polyester-based elastomer resin having an intrinsic viscosity of 1.752 dl/g, a melting point of 162° C., and a Shore A hardness of 80, and Resin B has an intrinsic viscosity of 0.648 dl/g and It is an antimony-free (Sb-free) low-melting polyester resin with a softening point of 148°C.

[Formula 2]

[Formula 3]

0.5 parts by weight of a chain extender and 0.2 parts by weight of an antioxidant were added to a mixture of 50 parts by weight of the resin A and 50 parts by weight of the resin B and 100 parts by weight of the mixture, and this was mixed with a twin screw extruder (screw diameter 32 mm, L/D = 40) was used for transesterification.

During the reaction and extrusion, the temperature of the resin in the extruder was adjusted to 250° C., the speed of the screw was 300 rpm, and the residence time was 1.5 minutes, and the prepared resin composition was cooled and then chipped to prepare a thermoplastic polyester-based elastomer resin.

Preparation Example 2

The same procedure as in Preparation Example 1, except that a low-melting polyester resin having an intrinsic viscosity of 0.648 dl/g and a melting point of 143° C. is used instead of the compound of Formula 3 as Resin B. An ester-based elastomer resin was prepared.

[Formula 4]

Preparation example 3

It was carried out in the same manner as in Preparation Example 1, except that the weight ratio of Resin A and Resin B was adjusted to 4:6.

Preparation example 4

It was carried out in the same manner as in Preparation Example 1, except that the weight ratio of Resin A and Resin B was adjusted to 3:7.

Preparation example 5

It was carried out in the same manner as in Preparation Example 1, except that the thermoplastic polyester-based elastomer resin was kneaded in a stationary kneader with 1.5 million divisions instead of a twin-screw extruder.

Comparative Preparation Example 1

It was carried out in the same manner as in Preparation Example 1, except that the weight ratio of Resin A and Resin B was adjusted to 1:9.

Comparative Preparation Example 2

It was carried out in the same manner as in Preparation Example 1, except that the weight ratio of Resin A and Resin B was adjusted to 7:3.

Comparative Preparation Example 3

It was carried out in the same manner as in Preparation Example 1, except that a commercial polyester-based elastomer resin represented by the following Chemical Formula 2 was used alone as the thermoplastic polyester-based elastomer resin. The commercial polyester-based elastomer resin had an intrinsic viscosity of 1.45 dl/g, a melting point of 152° C., and a Shore D hardness of 40.

[Formula 2]

Experimental Example 1: Measurement of elastic recovery rate

A tensile specimen was prepared using the thermoplastic polyester-based elastomer resin prepared according to the preparation example according to the ASTM D638 standard measurement method, and the elastic recovery rate was measured using a universal testing machine, and the results are shown in Table 1 below. it was

Experimental Example 2: Shore hardness measurement

The hardness of the thermoplastic polyester-based elastomer resin prepared according to the preparation example was measured in the Shore D type by ASTM D2240 standard measurement method, and the results are shown in Table 1 below.

Experimental Example 3: Measurement of Molar Ratio of Soft Segments

The molar ratio of the soft segment included in the thermoplastic polyester-based elastomer resin prepared according to the Preparation Example and Comparative Preparation Example was analyzed using NMR. The measured results are shown in Table 1 below.

	Resin A IV (dl/g) Melting point (℃) Content (wt%)‡	Resin B IV (dl/g) Melting point (℃) Content (wt%)‡	elastic recovery rate (%)	Shore hardness (D)	Soft segment molar ratio (mol%)
Preparation Example 1	1.752 dl/g 162℃ 50wt%	0.648 dl/g 148℃ 50wt%	96	37	16.5 mol%
Preparation Example 2	1.752 dl/g 162℃ 50wt%	0.648 dl/g 143℃ 50wt%	95	36	16.6 mol%
Preparation example 3	1.752 dl/g 162℃ 40wt%	0.648 dl/g 148℃ 60wt%	94	38	12.9 mol%
Preparation example 4	1.752 dl/g 162℃ 30wt%	0.648 dl/g 148℃ 70wt%	92	43	9.4 mol%
Preparation example 5	1.752 dl/g 162℃ 50wt%	0.648 dl/g 148℃ 50wt%	96	36	16.6 mol%
Comparative Preparation Example 1	1.752 dl/g 162℃ 10wt%	0.648 dl/g 148℃ 90wt%	break	68	2.8 mol%
Comparative Preparation Example 2	1.752 dl/g 162℃ 80 wt%	0.648 dl/g 148℃ 20 wt%	95	34	26.5 mol%
Comparative Preparation Example 3	1.450 dl/g 152℃ 100wt%	-	93	42	53 mol%

^* IV: Inherent Viscosity

^‡ Content in polyester-based elastomer resin

Example 1

The low-melting polyester resin and the thermoplastic polyester elastomer resin prepared according to Preparation Example 1 were subjected to composite spinning using a side-by-side spinneret to have a cross section as shown in FIG. The fineness was 6 denier and the fiber length was 64mm.

50% by weight of the heat-adhesive composite fiber and 50% by weight of the non-elastic polyethylene terephthalate fiber were mixed and carded to prepare a nonwoven web, followed by heat treatment in a tenter to prepare a nonwoven fabric. The processing temperature of the tenter was 170°C at the inlet side and 200°C at the outlet side.

Example 2

It was carried out in the same manner as in Example 1, except that the thermoplastic polyester-based elastomer resin prepared according to Preparation Example 2 was used.

Example 3

It was carried out in the same manner as in Example 1, except that the thermoplastic polyester-based elastomer resin prepared according to Preparation Example 3 was used.

Example 4

It was carried out in the same manner as in Example 1, except that the thermoplastic polyester-based elastomer resin prepared according to Preparation Example 4 was used.

Example 5

It was carried out in the same manner as in Example 1, except that the thermoplastic polyester-based elastomer resin prepared according to Preparation Example 5 was used.

Example 6

It was carried out in the same manner as in Example 1, except that the composite spinning was carried out using a sheath-core nozzle having the same cross section as in FIG. 2 .

Comparative Example 1

It was carried out in the same manner as in Example 1, except that the thermoplastic polyester-based elastomer resin prepared according to Comparative Preparation Example 1 was used.

Comparative Example 2

It was carried out in the same manner as in Example 1, except that the thermoplastic polyester-based elastomer resin prepared according to Comparative Preparation Example 2 was used.

Comparative Example 3

It was carried out in the same manner as in Example 1, except that only the thermoplastic polyester-based elastomer resin was independently spun to form a single fiber.

Experimental Example 4: Evaluation of elastic recovery rate of fiber aggregates

The prepared heat-adhesive nonwoven fabric was compressed to 75% of its initial thickness for 24 hours, and the compression set of the fiber aggregate was measured as the thickness after 1 hour of compression removal according to the following Relational Equation 2.

[Relational Expression 2]

The measurement results are shown in Table 2 below.

division	Heat Adhesive Composite Fiber	compression set (%)	Nonwoven processing yield*
Example 1	Preparation Example 1	9	○
Example 2	Preparation Example 2	8	○
Example 3	Preparation example 3	10	○
Example 4	Preparation example 4	14	○
Example 5	Preparation example 5	9	○
Example 6	Preparation Example 1	11	○
Comparative Example 1	Comparative Preparation Example 1	69	○
Comparative Example 2	Comparative Preparation Example 2	10	△
Comparative Example 3	Comparative Preparation Example 3	12	×

Claims (10)

Thermoplastic polyester-based elastomer resin, which is a block copolymer having a melting point of 110°C to 180°C and containing a soft segment having a structure represented by the following Chemical Formula 1 in an amount of 5 to 25 mol%; And a heat-adhesive composite fiber formed by composite spinning a polyester-based resin having a melting point of 230°C to 280°C:

[Formula 1]

In Formula 1, R represents a C _3-5 alkylene group, n is 5-45 free

represents the number.

According to claim 1,

The thermoplastic polyester-based elastomer resin,

Resin A comprising a compound represented by the following formula (2); and

Resin B comprising at least one of a compound represented by the following formula (3) and a compound represented by the following formula (4);

A heat-adhesive composite fiber comprising a block copolymer formed through a transesterification reaction between:

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4, P ¹ and P ² are each independently

or

, R ¹ and R ² are each independently a C ₃ to C ₅ alkylene group, R ³ to R ⁵ are each independently a C ₁ to C ₃ alkylene group, R ⁶ is C ₄ H ₈ and n is 5 to a rational number of 45, x is a rational number from 25 to 90, y is a rational number from 10 to 75, a and c are each independently a rational number from 55 to 80, and b and d are each independently a rational number from 20 to 45.

3. The method of claim 2,

The thermoplastic polyester-based elastomer resin is heat-adhesive composite fiber, characterized in that it is formed by reacting the resin A and the resin B in a weight ratio of 7:3 to 2:8.

3. The method of claim 2,

The resin A has a melting point of 140 ℃ to 175 ℃, the resin B is a heat-adhesive composite fiber, characterized in that it has a softening point of 110 ℃ to 150 ℃.

According to claim 1,

The thermoplastic polyester-based elastomer resin is heat-adhesive composite fiber, characterized in that the elastic recovery rate measured according to ASTM D638 standard measurement method is 80% to 99%.

A fiber assembly comprising the heat-adhesive composite fiber according to any one of claims 1 to 5.

7. The method of claim 6,

The fiber aggregate further comprises polyethylene terephthalate (PET) fibers.

7. The method of claim 6,

The fiber assembly, characterized in that the concentration of the heavy metal antimony (Sb), cobalt (Co) is 0.1ppm to 10ppm each independently.

A nonwoven fabric comprising the fiber aggregate according to any one of claims 6 to 8.

(1) a resin A comprising a compound represented by the following formula (2), and a resin B comprising at least one of a compound represented by the following formula (3) and a compound represented by the following formula (4) through a transesterification reaction to copolymerize a thermoplastic poly synthesizing an ester-based elastomer resin;

(2) the thermoplastic polyester-based elastomer resin and 230 ° C. to 280 ° C.

Composite spinning of a polyester-based resin having a melting point; Heat-adhesive fabric comprising

Manufacturing method of synthetic fiber:

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4, P ¹ and P ² are each independently

or

, R ¹ and R ² are each independently a C ₃ to C ₅ alkylene group, R ³ to R ⁵ are each independently a C ₁ to C ₃ alkylene group, R ₆ is C ₄ H ₈ and n is 5 to A rational number of 45, x is

a rational number from 25 to 90, y is a rational number from 10 to 75, a and c are each independently a rational number from 55 to 80, and b and d are each independently a rational number from 20 to 45.

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