Thermoplastic polyurethane composition and use thereof

文档序号：620872 发布日期：2021-05-07 浏览：20次中文

阅读说明：本技术 热塑性聚氨酯组合物及其用途 (Thermoplastic polyurethane composition and use thereof ) 是由陈永昌李毓麒杨曜嘉甘根娣朱利忠张同健邹圣杰于 2019-05-06 设计创作，主要内容包括：本发明涉及热塑性聚氨酯组合物及其用途。所述热塑性聚氨酯组合物包含由聚酯多元醇与多异氰酸酯制备的聚氨酯和抗氧剂。本发明的热塑性聚氨酯组合物可与其它热塑性聚合物一起用于熔融纺丝法来制备双组分纤维。(The present invention relates to thermoplastic polyurethane compositions and their use. The thermoplastic polyurethane composition comprises a polyurethane prepared from a polyester polyol and a polyisocyanate and an antioxidant. The thermoplastic polyurethane compositions of the present invention can be used with other thermoplastic polymers in a melt spinning process to make bicomponent fibers.)

1. A thermoplastic polyurethane composition comprising a polyurethane prepared from a polyester polyol and a polyisocyanate and an antioxidant.

2. The thermoplastic polyurethane composition of claim 1 further comprising a silicon-based lubricant.

3. The thermoplastic polyurethane composition of claim 1 or 2 wherein the polyester polyol is selected from the group consisting of a polycyclolactone diol and a polyester diol.

4. The thermoplastic polyurethane composition of claim 1 or 2 wherein the polyisocyanate is selected from the group consisting of vinyl diisocyanate, 1, 4-tetramethylene diisocyanate, hexamethylene diisocyanate, 1, 2-dodecane diisocyanate, cyclobutane-1, 3-diisocyanate, cyclohexane-1, 4-diisocyanate, 1-isocyanato-3, 3, 5-trimethyl-5-isocyanatomethylcyclohexane, hexahydrotoluene-2, 4-diisocyanate, hexahydrophenyl-1, 3-diisocyanate, hexahydrophenyl-1, 4-diisocyanate, perhydrodiphenylmethane-2, 4-diisocyanate, mixtures thereof, and mixtures thereof, Perhydrogenated diphenylmethane-4, 4-diisocyanate, phenylene-1, 3-diisocyanate, phenylene-1, 4-diisocyanate, tolylene-1, 4-diisocyanate, 3-dimethyl-4, 4-diphenyldiisocyanate, toluene-2, 4-diisocyanate, toluene-2, 6-diisocyanate, diphenylmethane-2, 4' -diisocyanate, diphenylmethane-2, 2' -diisocyanate, diphenylmethane-4, 4' -diisocyanate, diphenylmethane diisocyanate, mixtures of homologues of diphenylmethane diisocyanates having more rings, polyphenylmethane polyisocyanates, naphthylene-1, 5-diisocyanate and mixtures thereof.

5. The thermoplastic polyurethane composition of claim 1 or 2 wherein the antioxidant is present in an amount of from 0.5 to 1.5 weight percent, based on the total weight of the thermoplastic polyurethane composition.

6. The thermoplastic polyurethane composition of claim 2 wherein the silicon-based lubricant is present in an amount of 0.2 to 1.0 weight percent based on the total weight of the thermoplastic polyurethane composition.

7. A bicomponent fiber comprising:

i) the thermoplastic polyurethane composition of any of claims 1-6 as a first component; and

ii) a thermoplastic polymer different from the first component as a second component.

8. Bicomponent fiber according to claim 7, wherein the fiber fineness of the individual bicomponent fibers is 2-30 denier, preferably 2-10 denier.

9. The bicomponent fiber of claim 7 or 8, wherein the second component is selected from the group consisting of polyamide, polymethylmethacrylate, polyoxymethylene, polylactic acid, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate, polypropylene, and thermoplastic polyurethane having a shore hardness greater than 95A.

10. Bicomponent fiber according to claim 7 or 8, wherein the first component is present in the bicomponent fiber in an amount of 30-70 wt. -%, preferably 40-60 wt. -%, based on the total weight of the bicomponent fiber.

11. Bicomponent fiber according to claim 7 or 8, wherein the second component is present in the bicomponent fiber in an amount of 70-30 wt. -%, preferably 60-40 wt. -%, based on the total weight of the bicomponent fiber.

12. The bicomponent fiber of claim 7 or 8, wherein the bicomponent fiber is selected from the group consisting of sheath-core, side-by-side, and islands-in-the-sea bicomponent fibers.

13. Bicomponent fiber according to claim 12, wherein the first component is used as sheath or core, preferably as sheath, in the sheath-core bicomponent fiber.

14. The bicomponent fiber of claim 12, wherein in the islands-in-the-sea bicomponent fiber, the first component functions as an island or a sea.

15. A method of making the bicomponent fiber of any one of claims 7-14, comprising the steps of:

a) melting the first component and the second component in separate extruders;

b) extruding the first component and the second component together through a spin pack having one or more nozzles to obtain the bicomponent fiber; and

c) winding the bicomponent fiber into a filament coil by a winding roll.

16. The method as set forth in claim 15 wherein the first component and the second component are melted at a temperature in the range of 200 ℃ and 285 ℃.

17. The method of claim 15 or 16, wherein the temperature of the spin pack assembly is in the range of 220 ℃ and 285 ℃.

18. The method as claimed in claim 15 or 16, wherein the winding speed of the winding roller is 600-4000 m/min.

19. The method according to claim 15 or 16, wherein the bicomponent fiber is cooled to room temperature by cold air prior to step c).

20. A woven or knitted fabric comprising the bicomponent fiber of any one of claims 7-14 as warp or weft or both.

Technical Field

The present invention relates to the field of polyurethanes. In particular, the present invention relates to a thermoplastic polyurethane composition, a bicomponent fiber comprising the same, and a method of making the bicomponent fiber. The invention also relates to the use of said bicomponent fibres.

Background

Nylon fabrics having excellent durability, strength, softness, and gloss have long been used as base materials for apparel and textiles. Spandex fibers are often added to nylon-based fabrics to further provide elasticity and comfort, making the fabrics very popular in close-fitting applications such as intimate apparel, shaping underwear, swimwear, and athletic wear.

Manufacturers in the textile industry have been working on developing bicomponent or multicomponent fibers comprising polyurethane. For example, some manufacturers make bicomponent fibers by a solution spinning process. However, this method results in impurities (such as solvents, monomers and oligomers) in the final fiber, and these impurities have a negative effect on the mechanical properties or durability of the fiber or on human health.

Some manufacturers obtain polyurethane coated nylon or PET fibers by extrusion coating polyurethane onto nylon or PET fibers. However, the minimum diameter of the fibers obtained in this way is 0.1 mm. In addition, for the polyurethane-coated PET fiber, the polyurethane coating and the PET fiber are easily separated due to poor compatibility between the polyurethane coating and the PET fiber.

Some manufacturers are also attempting to prepare bicomponent fibers comprising polyurethane by melt compounding spinning. For example, EP 1,944,396a1 discloses an elastomeric core-sheath conjugate fiber useful in stretchable garments, made by a melt compounding spinning process, wherein both the core and the sheath are made of TPU. However, for the preparation of bicomponent fibers comprising polyurethane and other thermoplastic polymers than polyurethane, the spinning temperature of polyurethane is typically about 195-205 ℃, while the spinning temperature of polyamides, polyethylene terephthalate, etc. is above 230 ℃. If spinning is performed at this temperature, polyurethane is greatly degraded, so that the strength of the resulting bicomponent fiber is reduced, the fiber is easily broken, so that spinning is interrupted and the spinneret must be cleaned, thereby increasing production costs and reducing production efficiency.

Therefore, it would be desirable in the art to develop new polyurethane components for making bicomponent fibers that can be subjected to melt spinning with other thermoplastic polymers to obtain bicomponent fibers.

Disclosure of Invention

It is an object of the present invention to provide a novel polyurethane component for the preparation of bicomponent fibres which can be subjected to melt spinning together with other thermoplastic polymers to obtain bicomponent fibres.

According to a first aspect, the present invention provides a thermoplastic polyurethane composition comprising a polyurethane prepared from a polyester polyol and a polyisocyanate and an antioxidant.

According to a second aspect, the present invention provides a bicomponent fiber comprising:

i) the thermoplastic polyurethane composition of the present invention is used as a first component; and

ii) a thermoplastic polymer different from the first component as a second component.

According to a third aspect, the present invention provides a process for preparing the bicomponent fiber of the invention, comprising the steps of:

a) melting the first component and the second component in separate extruders;

b) extruding the first component and the second component together through a spin pack having one or more nozzles to obtain the bicomponent fiber; and

c) winding the bicomponent fiber into a filament coil by a winding roll.

According to a fourth aspect, the present invention provides a woven or knitted fabric comprising the bicomponent fibres of the invention as warp or weft or both.

The thermoplastic polyurethane compositions of the present invention can withstand processing temperatures of 220 ℃ and 280 ℃ and can thus be subjected to melt compounding spinning with a wide variety of thermoplastic polymers to produce bicomponent fibers. The bicomponent fibers of the present invention are characterized by abrasion resistance, 3D embossing effect, good liver feel (liver feeling), recyclable, dyeable with disperse dyes and acid dyes, and are used to prepare various types of woven or knitted fabrics for various applications, such as shoe uppers, glove skins, bag skins, garments, and the like.

Brief Description of Drawings

The invention will now be described with reference to the following drawings, in which:

FIG. 1 is a schematic flow diagram of a process for making bicomponent fibers according to one embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of a sheath-core (concentric) bicomponent fiber according to one embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of a sheath-core (eccentric) bicomponent fiber according to one embodiment of the invention;

FIG. 4 is a schematic cross-sectional view of a side-by-side bicomponent fiber according to one embodiment of the present invention;

FIG. 5 is a schematic cross-sectional view of an islands-in-sea bicomponent fiber according to one embodiment of the present invention;

FIG. 6 is a photograph of a bicomponent fiber/PET fiber blend fabric dyed with disperse dye in example 9, wherein the dark color indicates bicomponent fibers and the light color indicates PET fibers; and

FIG. 7 is a photograph of a bicomponent fiber fabric dyed with acid dye of example 10.

Detailed Description

Some specific embodiments of the present invention will be described below.

In some embodiments, the thermoplastic polyurethane composition further comprises a silicon-based lubricant.

The polyester polyol is preferably selected from the group consisting of polycyclolactone diols and polyester diols.

Examples of the polycyclolactone diol may include polycycloheptalactone diol, polycyclocaprolactone diol, polycyclovalerolactone diol, polycyclobutyrolactone diol, and polycyclopropiolactone diol.

The weight average molecular weight of the polycyclic lactone diol is preferably 2500-.

The polyester diol is preferably a linear polyester diol. The polyester diol may be prepared by polycondensation of a dicarboxylic acid and a diol. Examples of dicarboxylic acids used to prepare the polyester diols may include adipic acid, glutaric acid, succinic acid, malonic acid, and possible structural isomers thereof. Examples of diols used to prepare the polyester diols may include hexylene glycol, pentylene glycol, butylene glycol, propylene glycol, ethylene glycol, and possible structural isomers thereof.

The weight average molecular weight of the polyester diol is preferably 1000-4000 g/mol, more preferably 1500-3500 g/mol.

The polyisocyanate is preferably selected from the diisocyanates conventionally used in the field of thermoplastic polyurethanes, such as vinyl diisocyanate, 1, 4-tetramethylene diisocyanate, Hexamethylene Diisocyanate (HDI), 1, 2-dodecane diisocyanate, cyclobutane-1, 3-diisocyanate, cyclohexane-1, 4-diisocyanate, 1-isocyanato-3, 3, 5-trimethyl-5-isocyanatomethylcyclohexane, hexahydrotoluene-2, 4-diisocyanate, hexahydrophenyl-1, 3-diisocyanate, hexahydrophenyl-1, 4-diisocyanate, perhydrodiphenylmethane-2, 4-diisocyanate, perhydrogenated diphenylmethane-4, 4-diisocyanate, phenylene-1, 3-diisocyanate, phenylene-1, 4-diisocyanate, tolylene-1, 4-diisocyanate, 3-dimethyl-4, 4-diphenyldiisocyanate, toluene-2, 4-diisocyanate (TDI), toluene-2, 6-diisocyanate (TDI), diphenylmethane-2, 4' -diisocyanate (MDI), diphenylmethane-2, 2' -diisocyanate (MDI), diphenylmethane-4, 4' -diisocyanate (MDI), mixtures of diphenylmethane diisocyanates and/or homologues of diphenylmethane diisocyanates having more rings, polyphenylmethane polyisocyanates (polymeric MDI), Naphthalene-1, 5-diisocyanate (NDI) and mixtures thereof.

The person skilled in the art can easily determine the amount of diisocyanate required based on the amount of polyester polyol used.

The oxidizing agent may be an antioxidant commonly used in the field of fiber preparation.

The antioxidant is preferably selected from one or more of phosphorus-based antioxidants and phenol-containing antioxidants well known in the art.

Commercial examples of antioxidants may include Irgafos 126, Irganox 1010, and the like, available from BASF corporation.

According to one embodiment, the antioxidant comprises Irgafos 126 and Irganox 1010.

The antioxidant is preferably present in the thermoplastic polyurethane composition in an amount of from 0.5 to 1.5 weight percent, more preferably from 0.7 to 1.2 weight percent, based on the total weight of the thermoplastic polyurethane composition.

According to one embodiment, the antioxidant comprises 0.15 to 0.30 wt.% of Irgafos 126 and 0.25 to 0.40 wt.% of Irganox 1010, based on the total weight of the thermoplastic polyurethane composition.

The silicon-based lubricant is a silicon-based lubricant commonly used in the art, preferably a copolymer of polydimethylsiloxane having a weight average molecular weight of 1500-3000 (e.g., a weight average molecular weight of 2000) and polyethylene glycol, such as DOW CORNING SF 8427.

The silicon-based lubricant is preferably present in the thermoplastic polyurethane composition in an amount of 0.2 to 1.0% by weight, more preferably 0.4 to 0.7% by weight, based on the total weight of the thermoplastic polyurethane composition.

The thermoplastic polyurethane compositions of the present invention are resistant to high temperatures and can withstand temperatures of 260 ℃ (even 285 ℃), for example

High temperature of (2).

The thermoplastic polyurethane composition of the present invention may have a shore hardness of 88-92A.

The thermoplastic polyurethane composition of the invention is at 230 ℃ and 100s^-1The shear viscosity measured at the time of the reaction is 60 to 200Pas。

The thermoplastic polyurethane composition of the present invention can be prepared according to the methods of the art for preparing polyurethane resins, wherein an antioxidant and optionally a silicon-based lubricant are added.

For example, the thermoplastic polyurethane composition of the present invention can be prepared by: the polyester polyol and polyisocyanate are reacted using a prepolymerization process to form a prepolymer, and then the reaction is continued by adding a chain extender, an antioxidant and optionally a silicon-based lubricant, wherein the chain extender used is one commonly used in the preparation of thermoplastic polyurethanes.

According to a second aspect, the present invention provides a bicomponent fiber comprising:

i) the thermoplastic polyurethane composition of the present invention is used as a first component; and

ii) a thermoplastic polymer different from the first component as a second component.

The individual bicomponent fibers have a fiber fineness of 2 to 30 denier, preferably 2 to 10 denier. The second component is selected from the group consisting of Polyamide (PA), Polymethylmethacrylate (PMMA), Polyoxymethylene (POM), polylactic acid (PLA), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polypropylene (PP) and thermoplastic polyurethane with a shore hardness greater than 95.

In the bicomponent fiber, the first component is present in the bicomponent fiber in an amount of preferably 30 to 70 wt.%, more preferably 40 to 60 wt.%, based on the total weight of the bicomponent fiber.

In the bicomponent fiber, the second component is present in the bicomponent fiber in an amount of preferably 70 to 30 wt.%, more preferably 60 to 40 wt.%, based on the total weight of the bicomponent fiber.

The bicomponent fiber can be selected from the group consisting of sheath-core (see fig. 2 and 3), side-by-side (see fig. 4), and islands-in-the-sea (see fig. 5) bicomponent fibers.

The sheath-core bicomponent fibers can be concentric (see fig. 2) or eccentric (see fig. 3), preferably concentric.

In sheath-core bicomponent fibers, the first component serves as a sheath or core, preferably as a sheath.

In the islands-in-sea type bicomponent fiber, the second component functions as an island or sea.

Neither the first component nor the second component used to prepare the bicomponent fibers of the present invention contain a crosslinking agent, particularly a non-polyether crosslinking agent.

The bicomponent fibers of the present invention can be dyed with disperse dyes (e.g., DyStar Diamix Blue and Yellow series) and Acid dyes (e.g., Acid Yellow 199 and Acid Blue 62), and the like.

In the case of dyeing with disperse dyes, the dyeing temperature is 100-150 ℃, preferably 130 ℃, and the dyeing time is 60 minutes or more, for example 60-70 minutes.

In the case of dyeing with acid dyes, the dyeing temperature is from 80 to 120 ℃, preferably 100 ℃, and the dyeing time is from 45 minutes or more, for example from 45 to 60 minutes.

The bicomponent fibers of the present invention can be prepared into fabrics by weaving or knitting processes.

The bicomponent fibers of the present invention may be used as the warp, the weft, or both.

Suitable weaving devices can be, for example, air-jet looms, water-jet looms, rapier looms, etc.

Suitable knitting devices may be, for example, flat knitting machines, circular knitting machines, etc. When processing is performed using a flat knitting machine, a ceramic guide nozzle is preferably used.

The fabric may be, for example, a mesh or the like.

According to a third aspect, the present invention provides a process for preparing the bicomponent fiber of the invention, comprising the steps of:

a) melting the first component and the second component in separate extruders;

b) extruding the first component and the second component together through a spin pack having one or more nozzles to obtain the bicomponent fiber; and

c) winding the bicomponent fiber into a filament coil by a winding roll.

Preferably, in step a), the first component and the second component are melted at a temperature in the range of 200 ℃ and 285 ℃, preferably 205 ℃ and 270 ℃.

The first component and the second component may melt at different temperatures. For example, the first component may be melted at a temperature in the range of 200 ℃ to 240 ℃, preferably 205 ℃ to 230 ℃.

The person skilled in the art can easily determine the temperature at which the second component is melted, depending on the second component used. For example, when the second resin is a polyamide, the second resin may be melted at a temperature in the range of 230-.

Preferably, in step b), the temperature of the spinning assembly is in the range of 220-285 ℃, preferably 230-260 ℃ and more preferably 230-240 ℃.

Optionally, after extruding the first and second components to obtain the bicomponent fiber, adding a lubricating oil to the bicomponent fiber. For example, lubricating oil may be added to the bicomponent fibers by spraying or by rolling.

Optionally, the bicomponent fibers are drawn, preferably hot drawn, prior to winding. For example, heated rollers can be used to thermally stretch the bicomponent fibers.

Preferably, in step c), the winding speed of the winding roller is 600-4000m/min, preferably 1000-3500 m/min.

Optionally, before step c), the bicomponent fibers are cooled to room temperature by means of cold air.

Optionally, the bicomponent fibers are twisted by a twister to obtain twisted fibers.

In the preparation of the bicomponent fibers of the present invention, no crosslinking agent, particularly a non-polyether crosslinking agent, is used.

According to a fourth aspect, the present invention provides a woven or knitted fabric comprising the bicomponent fibres of the invention as warp or weft or both.

The bicomponent fibers may comprise from 10 to 100% by weight of the woven or knitted fabric.

By incorporating the bicomponent fibers of the present invention into a fabric (e.g., a mesh), the properties of the fabric (e.g., mesh) can have the following variations:

increased surface friction;

improved wear resistance;

improved tear strength after heat treatment;

the hot pressing process at low temperatures, e.g. 110-;

in the secondary forming by insert injection molding, the adhesion between the fabric and other polymers, such as commercially available TPU, TPE (thermoplastic elastomer) and TPEE (thermoplastic polyester elastomer), is increased, for example when the other polymers are directly injected over the fabric (for example a mesh) by means of insert injection molding;

provide a firm feel;

when the bicomponent fibers are blended with polyester and nylon fibers, the fibers can be dyed simultaneously without separate color matching.

Fibers that may be woven or knitted with the bicomponent fibers of the invention are, for example, polyester fibers (e.g., PET fibers), polyamide fibers, viscose fibers, cotton fibers, spandex fibers, Dyneema (DSM), Kevlar (DuPont), Cordura (DuPont), and the like.

The woven or knitted fabric may be used in shoe uppers, shoe laces, glove skins, wrap skins, sandwich netting, furniture fabrics, apparel, and the like.

In the description and claims of this application, all numbers expressing quantities, percentages, parts by weight, and so forth, are to be understood as being modified in all instances by the term "about".

The present invention will be described in detail with reference to the following specific examples. However, those skilled in the art will readily appreciate that the embodiments herein are for illustrative purposes only and that the scope of the present invention is not limited thereto.

Examples

The used raw materials are as follows:

PLA：

index (I)	Unit of	Numerical value	Test method
				Specific gravity of	g/cm³	1.24	D792
Relative viscosity		3.1±0.1	CD Internal Viscotek method
				Melt index	g/10min(210°C)	15-30	D1238
Melting Point	°C	155-170	D3417
				Glass transition temperature	°C	55-60	D3418
Water content ratio	%	≤0.04	Karl Fischer

PA1 and PA 2:

index (I)	Unit of	PA1 numerical value	PA2 numerical value	Test method
					Specific gravity of	g/cm³	1.14	1.13	ISO 1183
Viscosity of the oil	cm³/g	153		ISO 1628-1
					Bulk density	Kg/m³	~700	~670	ISO 60
Melting Point	°C	~210	~220	ISO 1346 C, 10K/min
					Water content ratio	%	≤0.02	≤0.06	Karl Fischer
Terminal amino group	%		43±2
					Extracts of plants	%		≤0.6

The test method comprises the following steps:

the Shore hardness is determined by means of a durometer in accordance with ISO 868: 2003.

Viscosity was determined according to ISO 11443:2005 using capillary and slot die rheometers.

Melting points were determined by DSC according to ASTM D3418/E1356.

The fineness, tensile strength and elongation at break were determined according to GB/T14343-.

The shrinkage was determined according to GB/T6505-.

The oil content was determined according to GB/T6504-.

The colour fastness to light was tested according to Adidas FT-11 under the following test conditions: 550W and black body temperature of 70 ℃ for 2 hours.

Migration fastness was tested according to Adidas FT-02 under the following test conditions: 45N and 50 ℃ for 16 hours.

The Courtauld test was performed according to Adidas FT-08 under the following test conditions: 45N and 50 ℃ for 16 hours.

In the following examples, the component amounts are based on their weight.

Example 1

59.8g of poly (butylene adipate) glycol (polybutylene glycol adipate, weight average molecular weight 1500) and 30.9 g of diphenylmethane-4, 4-diisocyanate were reacted at 210 ℃ and 230 ℃ for about 1 minute using a prepolymerization method to form a polymer, and then 7.8g of 1, 4-butanediol, 0.125g of Irganox 1010 and 0.125g of Irgafos 126 were added. The temperature was controlled at 230 ℃ and the reaction was continued for 30 seconds to obtain the thermoplastic polyurethane composition TPU 1.

Example 2

59.3g of poly (butylene adipate) glycol (weight average molecular weight 2000) and 30.4g of diphenylmethane-4, 4-diisocyanate were reacted at 230 ℃ for about 1 minute using a prepolymerization method to form a polymer, and then 8.3g of 1, 4-butanediol, 0.31g of Irganox 1010, 0.31g of Irgafos 126 and 0.5g of a silicon-based lubricant (DOW CORNING SF8427) were added. The temperature was controlled at 230 ℃ and the reaction was continued for 30 seconds to obtain the thermoplastic polyurethane composition TPU 2.

Example 3

58.8g of a cyclohexactone diol (weight average molecular weight of 3000) and 30.1g of diphenylmethane-4, 4-diisocyanate were reacted at 210 ℃ and 230 ℃ using a prepolymerization method to form a polymer until a temperature of 225 ℃ was reached for about 1 minute, and then 9.1g of 1, 4-butanediol, 0.31g of Irganox 1010, 0.31g of Irgafos 126 and 0.5g of a silicon-based lubricant (DOW CORNING SF8427) were added. The temperature was controlled at 230 ℃ and the reaction was continued for 30 seconds to obtain the thermoplastic polyurethane composition TPU 3.

Table 1: properties of the thermoplastic polyurethane compositions prepared in examples 1 to 3

Example 4

The TPU1 and PLA obtained in example 1 were dried separately in a dehumidifier until the water content therein was below 100 ppm. The dried TPU1 and PLA were fed into two separate single screw extruders a and B, respectively, where the temperature of screw extruder a was 205 ℃ and the temperature of screw extruder B was 230 ℃. TPU1 and PLA were mixed via a gear pump at a ratio of 50: 50 by weight was fed to a spin pack maintained at 230 ℃, the melt was extruded through orifices (6 orifices) in the spinneret into bicomponent fibers, and the bicomponent fibers were air cooled (at 23 ℃ and 0.4 m/s), oiled, sized, and wound (at a winding speed of 2800 m/min) into a package. Spinning was carried out stably for more than 72 hours and the pressure rise of the assembly was less than 10MPa within 72 hours and the number of interruptions during spinning was less than 10 times within 72 hours.