Polymer porous foaming fiber as well as preparation method and application thereof

Abstract

The invention discloses a polymer porous foaming fiber as well as a preparation method and application thereof, and relates to the technical field of foaming materials. By adopting the method provided by the invention, the polymer particles containing the foaming agent are firstly subjected to low-temperature treatment and then extruded by adopting a specific process, so that the escape and foaming rate of the foaming agent in the low-hardness raw material are delayed, and the polymer raw material with the hardness as low as Shore 25A can be controllably foamed; the obtained fiber is good in foaming behavior, stable in extrusion and uniform in foaming wire diameter, the foam hole size is 12-26 microns, the foam holes are uniformly distributed from the center to the outer layer, the diameter of the obtained fiber is 0.54 mm or below, the density is as low as 0.71 g / cm < 3 > or below, and the prepared fiber has a closed porous structure, is good in heat preservation performance and can be used for preparing a composite material. The method is suitable for preparation in the fields of clothing and the like and has good application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of foaming materials, and in particular to a polymer porous foaming fiber and a preparation method and application thereof. Background Art

[0002] The porous structure of polymer porous fibers gives fiber materials lightweight characteristics and excellent elasticity, thermal insulation, and radiation cooling properties. Fabrics woven from polymer porous fibers have excellent air and moisture permeability and are expected to be used in wearables, smart clothing, multifunctional sportswear, shoe uppers, and other fields. However, the pore structure of existing porous fibers is mostly open-pore, which has the problem of easy water absorption, increased density, and poor thermal insulation after water absorption.

[0003] At present, it has been reported that supercritical fluid can be used as a foaming agent to impregnate polymer wires, and then polymer porous fibers can be prepared by micro-extrusion foaming. The porous fibers prepared by this impregnation-micro-extrusion method have a pore structure that is mainly a closed-cell structure, which makes the prepared polymer porous fibers have stable thermal insulation performance in different use environments. However, the polymer material impregnated with supercritical fluid will be affected by the plasticizing effect of the supercritical fluid, and the hardness of the wire will be reduced, and the micro-extrusion foaming system is not suitable for processing polymer materials with a hardness lower than Shore hardness 80A. However, as people have higher and higher requirements for comfort in the fields of wearable devices, clothing, etc., how to micro-extrude and foam low-hardness polymer wires and improve the comfort of the resulting porous fibers has become a difficult problem that needs to be solved urgently. Summary of the invention

[0004] In order to address the deficiencies in the prior art, the present invention provides a method for preparing a polymer porous foamed fiber. First, polymer particles containing a foaming agent are treated at low temperature, and then extrusion foaming is performed using a specific process, thereby slowing down the escape velocity and foaming speed of the foaming agent in the raw material, and achieving controllable foaming of polymer particles with lower hardness, so that the resulting foamed fiber can better meet the comfort requirements in the fields of wear and so on.

[0005] Another object of the present invention is to provide a polymer porous foamed fiber.

[0006] Another object of the present invention is to provide an application of the polymer porous foamed fiber.

[0007] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0008] A method for preparing a polymer porous foamed fiber comprises the following steps:

[0009] S1. The polymer particles containing the foaming agent are subjected to a low-temperature treatment for ≥30 min at a temperature ≤-15°C and a humidity ≤30% to obtain a low-temperature treated masterbatch; the concentration of the foaming agent in the polymer particles containing the foaming agent is 0.5 to 8 wt%;

[0010] S2. Extruding and foaming the low-temperature treated masterbatch obtained in step S1 to obtain a foamed melt; the extrusion foaming is performed using a single-screw extruder, and the single-screw extruder sequentially comprises a first heating section, a second heating section, and a third heating section, wherein the temperature of the first heating section is 10 to 30° C., the temperature of the second heating section is 100 to 260° C., and the temperature of the third heating section is 270 to 430° C., wherein the real-time temperature of the third heating section is higher than the temperature of the second heating section;

[0011] S3. The foamed melt obtained in step S1 is stretched and shaped to obtain a polymer porous foamed fiber.

[0012] The lower the hardness of the polymer, the easier it is to cause the escape loss of the foaming agent during storage, transfer, etc., and when foaming is performed by micro-extrusion foaming, the higher the difficulty of achieving controllable foaming. For this reason, the preparation method provided by the present invention first performs low-temperature treatment on the polymer particles containing the foaming agent in step S1, which can not only reduce the loss of the foaming agent, but also delay the foaming rate of the foaming agent in the process of heating foaming, and avoid the uncontrollable foaming rate and degree in the foaming process of the low-hardness raw material. After low-temperature treatment, the polymer particles containing the foaming agent are transported to a single screw extruder for controllable foaming, and then through drawing and shaping, the polymer foam fiber can be obtained. Wherein, step S2 controls the temperature of different heating sections, which can make the polymer system gradually transition from a glassy state to a high elastic state and a viscous flow state, and cell nucleation and rapid cell growth occur. Among them, the temperature of the first heating section is controlled to be only 10-30°C, and the loss rate of the polymer particle raw material containing the foaming agent is low enough when passing through the first heating section, so that the polymer undergoes sufficient phase change and foaming later. The polymer porous foamed fiber prepared by the preparation method provided by the present invention is rich in uniformly distributed foam cells, and the pore structure is closed-cell, with excellent thermal insulation and other properties. At the same time, due to the reduction in the hardness of the raw material, the hardness of the fiber is also reduced, which can better meet the comfort needs of clothing and other fields. It should be noted that in order to achieve controllable foaming, especially the controlled foaming of low-hardness raw materials, the present invention also needs to limit the content of the foaming agent in the polymer raw material particles in step S1. If the content of the foaming agent is too low, the foaming agent will still be lost during the micro-extrusion process of step S2 despite the low-temperature treatment; if the content of the foaming agent is too high, the low-hardness polymer raw material is prone to excessive foaming during the micro-extrusion process.

[0013] In a specific embodiment of the present invention, the preparation method of the polymer porous foam fiber provided by the present invention is carried out in a micro-extrusion device, and the micro-extrusion device includes a feeding unit, a micro-extrusion unit, a shaping unit, and a drawing unit; the micro-extrusion unit is a single-screw extruder; the shaping unit includes a shaping corridor, and the drawing unit includes one or more hot drawing sections, wherein one hot drawing section includes two hot rollers and a hot plate. More specifically, the speed of the hot roller is 0 to 600 m / min, the temperature is 30 to 200°C, the temperature of the hot plate is 30 to 200°C, and the hot drawing ratio is 1 to 5 times, preferably 2 to 3 times. The drawing unit of the present invention mainly adopts a post-drawing process. Through the action of the hot roller and the hot plate, the drawing ratio can be controlled by controlling the heating temperature, the processing speed, etc. without sacrificing its pore structure, so as to obtain polymer porous fibers of different diameters.

[0014] In a specific embodiment of the present invention, the polymer particles containing a foaming agent in step S1 are prepared by blending the polymer particles with the foaming agent and melt extruding. Wherein, when the foaming agent is a fluid foaming agent, the polymer particles are blended with the foaming agent by impregnation. More specifically, the melt extrusion is performed using a twin-screw extruder. More specifically, the melt extrusion further includes a cutting step, and the cutting is performed using a pelletizer.

[0015] In a specific embodiment of the present invention, the temperature control accuracy of the low temperature treatment in step S1 is ±1° C., and the loss rate of the foaming agent in the polymer particles containing the foaming agent during the low temperature treatment is <5%.

[0016] In a specific embodiment of the present invention, step S2 controls the temperature of the first heating section to be 10-30° C. by connecting the first heating section to at least one of an external water cooling system and a cold air system.

[0017] Preferably, the temperature of the low temperature treatment in step S1 is -40 to -15°C, and the humidity is 1 to 5%.

[0018] Preferably, the concentration of the foaming agent in the polymer particles containing the foaming agent in step S1 is 2.5-7.5 wt %.

[0019] In a specific embodiment of the present invention, the shape of the polymer particles containing a foaming agent in step S1 is at least one of round, oval, and knife-cut particles, and the average diameter of the particles is 0.5 to 5.0 mm, and the fluctuation range of the average diameter is ±0.5 to 1 mm.

[0020] More preferably, the polymer particles containing a blowing agent in step S1 include the following components calculated by mass:

[0021] 80-100 parts of polymer, 2-7.5 parts of foaming agent, 0-10 parts of nucleating agent, 0-1 part of chain extender, 0-0.5 parts of antioxidant, and 0-2 parts of antistatic agent.

[0022] More preferably, the polymer includes at least one of a crystalline polymer, an amorphous polymer, a semi-crystalline polymer, and a thermoplastic elastomer. In a specific embodiment of the present invention, the melting point of the polymer is 100-400°C.

[0023] More preferably, the amorphous polymer includes at least one of PS, PMMA, PEI, PI, and PSF.

[0024] More preferably, the semi-crystalline polymer includes at least one of PET, PLA, and PEEK.

[0025] More preferably, the crystalline polymer includes at least one of PE, PP and PA.

[0026] More preferably, the thermoplastic elastomer includes at least one of EVA, TPE, TPU, TPEE, and PEBA.

[0027] More preferably, the hardness of the thermoplastic elastomer is Shore A20 to Shore A70.

[0028] The hardness of amorphous polymers, semi-crystalline polymers and crystalline polymers commonly used in the art is generally high and cannot be adjusted. The present invention focuses on the foaming of low-hardness raw materials, and preferably uses a thermoplastic elastomer with a hardness of Shore A20 to Shore A70 to prepare the raw material.

[0029] More preferably, the foaming agent includes at least one of a solid foaming agent and a fluid foaming agent.

[0030] More preferably, the fluid foaming agent includes at least one of CO2, N2, n-pentane, isopentane, butane, and Freon.

[0031] More preferably, the solid foaming agent includes at least one of expandable microspheres, carbonates, azodicarbonamide, and N,N-dinitrosopentamethylenetetramine.

[0032] More preferably, the nucleating agent includes at least one of calcium carbonate, talc, mica, montmorillonite, nano-silica, carbon black, and carbon nanotubes.

[0033] More preferably, the chain extender comprises at least one of a difunctional acid derivative, an isocyanate, an anhydride, and an epoxide.

[0034] More preferably, the antioxidant includes at least one of an amine antioxidant and a phosphorus antioxidant.

[0035] More preferably, the particle size of the nucleating agent is 0.05 to 5 μm.

[0036] More preferably, the antistatic agent includes a hydrophobic antistatic auxiliary agent.

[0037] More preferably, when the foaming agent in the polymer particles containing the foaming agent in step S1 is a fluid foaming agent, the fluid foaming agent is blended with the polymer particles by high-pressure impregnation to obtain the polymer particles containing the foaming agent, and the high-pressure impregnation is performed at 5 to 30 MPa.

[0038] In a specific embodiment of the present invention, the temperature control accuracy of the single screw extruder in step S2 is 0.5-5°C, preferably 1-3°C.

[0039] In a specific embodiment of the present invention, the residence time of the low temperature treated masterbatch in the first heating section in step S2 is 0.1 to 1.5 s, and the loss rate of the foaming agent when the low temperature treated masterbatch stays in the first heating section is less than 5%.

[0040] In a specific embodiment of the present invention, the rotation speed of the single screw extruder in step S2 is 20 to 40 rpm.

[0041] The present invention also protects the polymer porous foamed fiber prepared by the above preparation method.

[0042] In a specific embodiment of the present invention, the obtained polymer porous foamed fiber has a diameter of 0.15 to 0.3 mm and a density of 0.4 to 0.8 g / cm 3 The pore size distribution range is 13 to 26 μm.

[0043] In a specific embodiment of the present invention, the pore structure of the obtained polymer porous foam fiber is closed-cell. This is because during the heating process, the pores undergo a process of nucleation, growth, and rapid cooling, and the pores are shaped during the cooling process. In this process, the closer to the fiber epidermis, the faster the gas escapes and the faster the cooling rate, the more the pores collapse and form a cortex, so the fiber as a whole presents a closed-cell structure.

[0044] The present invention also protects the application of the above-mentioned polymer porous foamed fiber in outdoor sports shoes and clothing, electronic wearable devices, functional clothing, and catalysis fields.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The method provided by the present invention can controllably foam a polymer raw material with a Shore hardness as low as 25A to obtain porous polymer foamed fibers. The obtained fibers have good foaming behavior, stable extrusion, uniform diameter of the foamed filaments, pore sizes of 12 to 26 μm, and are distributed from the center to the outer layer. The diameter of the obtained fibers is less than 0.54 mm, and the density is as low as 0.71 g / cm 3 Within, it has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a SEM image of the polymer porous fiber obtained in Example 5 of the present invention. DETAILED DESCRIPTION

[0048] The present invention is further described below in conjunction with specific embodiments, but the embodiments do not limit the present invention in any form. Unless otherwise specified, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents. Among them, the raw material information in each embodiment and comparative example is as follows (the part involving hardness refers to Shore hardness):

[0049] Amorphous polymer A

[0050] A1, polystyrene PS, brand GPPS158K, BASF-Yangzi;

[0051] A2, polyetherimide PEI, grade 1000, SABIC;

[0052] Crystalline polymer B

[0053] B1, low-density polyethylene LDPE, brand 2426H, Maoming Petrochemical;

[0054] B2, PEEK, grade 1000, Mitsubishi Chemical;

[0055] Thermoplastic Elastomer C

[0056] C1, thermoplastic polyurethane EVA, hardness 25A, BASF, Germany.

[0057] C2, thermoplastic elastomer TPE, hardness 70A, DuPont, USA.

[0058] Foaming agent:

[0059] AC foaming agent azodicarbonamide, commercially available.

[0060] CO2 fluid, commercially available.

[0061] Mixed foaming agent: includes AC foaming agent and CO2 fluid in a mass ratio of 1:1.

[0062] Nucleating agent:

[0063] Calcium carbonate, with an average particle size of 1 μm, is commercially available.

[0064] Chain Extender:

[0065] Epoxy chain extender, commercially available.

[0066] Antioxidants:

[0067] Hindered phenolic antioxidant, commercially available.

[0068] Antistatic Agent:

[0069] Hydrophobic antistatic agent, commercially available.

[0070] Examples 1 to 10 and Comparative Examples 1 to 2

[0071] This embodiment and comparative example provide a series of methods for preparing polymer porous foamed fibers with different raw materials and process parameters, including the following steps:

[0072] S1. The polymer particles containing the foaming agent are subjected to low temperature treatment for 30 minutes at a temperature below -15°C and a humidity of 1 to 30% to obtain a low temperature treated masterbatch;

[0073] S2. Extruding and foaming the low-temperature treated masterbatch obtained in step S1 to obtain a foamed melt; the extrusion foaming is performed using a single-screw extruder, and the single-screw extruder sequentially comprises a first heating section, a second heating section, and a third heating section, wherein the temperature of the first heating section is 25° C., the temperature of the second heating section is 140° C., and the temperature of the third heating section is 270° C., wherein the real-time temperature of the third heating section is higher than the temperature of the second heating section;

[0074] S3. The foamed melt obtained in step S1 is stretched and shaped to obtain a polymer porous foamed fiber;

[0075] The polymer particles containing a foaming agent in step S1 include the following components calculated by mass:

[0076] 100 parts of polymer, 0.1-10 parts of foaming agent, 5 parts of nucleating agent, 0.5 parts of chain extender, 0.25 parts of antioxidant, 1 part of antistatic agent;

[0077] Wherein, when the foaming agent is CO2 fluid, the foaming agent and polymer particles are blended by high pressure impregnation to obtain polymer particles containing the foaming agent, and the high pressure impregnation is performed at 20 MPa;

[0078] When the blowing agent is a mixed blowing agent, AC blowing agent is firstly blended with polymer particles, and then CO2 fluid is blended with polymer particles to obtain polymer particles containing blowing agent, and the high-pressure impregnation is performed at 20 MPa.

[0079] The specific raw materials and process parameters in this example and the comparative example are shown in Table 1 below:

[0080] Table 1. Raw materials and process parameters in Examples 1 to 10 and Comparative Examples 1 to 2

[0081]

[0082] Comparative Example 3

[0083] A method for preparing a polymer porous foamed fiber, which is different from Example 5 only in that:

[0084] The low temperature treatment temperature in step S1 is -10°C.

[0085] Comparative Example 4

[0086] A method for preparing a polymer porous foamed fiber, which is different from Example 5 only in that:

[0087] The humidity during low temperature treatment in step S1 is 50%.

[0088] Comparative Example 5

[0089] A method for preparing a polymer porous foamed fiber, which is different from Example 5 only in that:

[0090] The low-temperature treatment in step S1 is not performed, and the polymer particles containing the foaming agent are directly extruded and foamed.

[0091] Comparative Example 6

[0092] A method for preparing a polymer porous foamed fiber, which differs from Example 1 only in that:

[0093] The low-temperature treatment in step S1 is not performed, and the polymer particles containing the foaming agent are directly extruded and foamed.

[0094] Comparative Example 7

[0095] A method for preparing a polymer porous foamed fiber, which is different from Example 5 only in that:

[0096] The temperature of the first heating section of the single screw extruder in step S2 is 100°C.

[0097] Performance Testing

[0098] Foaming behavior test: SEM was used to observe the pore morphology.

[0099] Cell size and distribution test: measured by visual observation.

[0100] Fiber diameter test: measured with a caliper.

[0101] Fiber density test: measured by drainage method.

[0102] Fiber hardness test: measured using a hardness tester.

[0103] The specific performance test data is shown in Table 2 below:

[0104] Table 2. Performance test data of the fibers obtained in the examples and comparative examples

[0105]

[0106]

[0107]

[0108]

[0109] According to the data in Table 2 above, it can be seen that the method provided by the present invention can controllably foam the polymer raw material with a Shore hardness as low as 25A, thereby obtaining a porous polymer fiber with good foaming behavior. The obtained fiber is extruded smoothly, the diameter of the foamed filament is uniform, the pore size is moderate, 12 to 26 μm, and the pores are distributed from the center to the outer layer. The pore size difference is not large, and the diameter of the obtained fiber is small, only less than 0.54 mm, and the density is as low as 0.71 g / cm 3 At the same time, according to Figure 1 It can be seen that the fiber prepared in the present invention has a closed-cell porous structure and good thermal insulation performance, and is suitable for the preparation in the fields of clothing and the like.

[0110] According to the data of Examples 5, 7-8, and Comparative Example 3, when the method of the present invention is used to prepare the polymer porous foamed fiber, the low temperature treatment temperature in step S1 should be controlled within the range of ≤-15°C. If the temperature of the low temperature treatment in step S1 is too high (Comparative Example 3), it will cause excessive escape of the foaming agent, so the foaming degree is uncontrollable. However, when the temperature of the low temperature treatment is further reduced to -40°C (Example 7), the foaming structure of the polymer fiber is not improved much, but the energy consumption is increased. Therefore, the present invention preferably controls the low temperature treatment temperature within the range of -40 to -15°C.

[0111] According to the data of Examples 5, 9-10 and Comparative Example 4, it can be seen that the humidity of the low-temperature treatment is too high (Comparative Example 4). In an environment with a temperature below zero, water vapor easily forms crystals on the surface of the polymer raw material, which affects the effect of heating and foaming during extrusion.

[0112] According to the data of Example 5 and Comparative Examples 1-2, it can be seen that the preparation method of the present invention can be used to prepare polymer porous foamed fibers, and polymer raw materials with hardness as low as 25A can be controlled to foam, but the content of the foaming agent in the polymer raw material needs to be limited. If the foaming agent content is too low (Comparative Example 1), the foaming agent will still be lost during the micro-extrusion process despite the low-temperature treatment, which will lead to difficulty in controllable foaming, irregular distribution of pores in the obtained polymer foamed fibers, uneven fiber diameter, and partial non-foaming. If the foaming agent content is too high (Comparative Example 2), low-hardness polymer raw materials are prone to excessive foaming during micro-extrusion.

[0113] According to the data of Comparative Examples 5 and 6, if the low-temperature treatment step in step S1 is not performed, the foaming agent in the polymer raw material will easily escape and be lost during the extrusion process, resulting in uncontrollable foaming, and there will be almost no cells or only a small number of cells inside the polymer foam fiber.

[0114] According to the data of Comparative Example 7, it can be seen that in addition to the low-temperature treatment step of step S1, the specific extrusion process of the present invention should be used to extrude the polymer raw material to obtain controllably foamed polymer foamed fibers.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing a polymer porous foam fiber, characterized in that: The steps include: S1. The polymer particles containing the foaming agent are subjected to a low-temperature treatment for ≥30 min at a temperature ≤-15°C and a humidity ≤30% to obtain a low-temperature treated masterbatch; the concentration of the foaming agent in the polymer particles containing the foaming agent is 0.5 to 8 wt%; S2. Extruding and foaming the low-temperature treated masterbatch obtained in step S1 to obtain a foamed melt; the extrusion foaming is performed using a single-screw extruder, and the single-screw extruder sequentially comprises a first heating section, a second heating section, and a third heating section, wherein the temperature of the first heating section is 10 to 30° C., the temperature of the second heating section is 100 to 260° C., and the temperature of the third heating section is 270 to 430° C., wherein the real-time temperature of the third heating section is higher than the temperature of the second heating section; S3. The foamed melt obtained in step S1 is stretched and shaped to obtain a polymer porous foamed fiber.

2. The method for preparing the polymer porous foamed fiber according to claim 1, characterized in that: The temperature of the low temperature treatment in step S1 is -40 to -15°C, and the humidity is 1 to 5%.

3. The method for preparing the polymer porous foamed fiber according to claim 1, characterized in that: The concentration of the foaming agent in the polymer particles containing the foaming agent in step S1 is 2.5-7.5wt%.

4. The method for preparing the polymer porous foamed fiber according to claim 3, characterized in that: The polymer particles containing a foaming agent in step S1 include the following components calculated by mass: 80-100 parts of polymer, 2-7.5 parts of foaming agent, 0-10 parts of nucleating agent, 0-1 part of chain extender, 0-0.5 parts of antioxidant, and 0-2 parts of antistatic agent.

5. The method for preparing the polymer porous foamed fiber according to claim 4, characterized in that: Include at least one of the following (a) to (g): (a) The polymer in step S1 includes at least one of a crystalline polymer, an amorphous polymer, a semi-crystalline polymer, and a thermoplastic elastomer; (b) the foaming agent comprises at least one of a solid foaming agent and a fluid foaming agent; (c) the nucleating agent comprises at least one of calcium carbonate, talc, mica, montmorillonite, nano-silica, carbon black, and carbon nanotubes; (d) the chain extender comprises at least one of a difunctional acid derivative, an isocyanate, an anhydride, and an epoxide; (e) the antioxidant comprises at least one of an amine antioxidant and a phosphorus antioxidant; (f) the particle size of the nucleating agent is 0.05 to 5 μm; (g) The antistatic agent includes a hydrophobic antistatic auxiliary agent.

6. The method for preparing the polymer porous foamed fiber according to claim 5, characterized in that: Including at least one of the following (h) to (m): (h) the amorphous polymer includes at least one of PS, PMMA, PEI, PI, and PSF; (i) the semi-crystalline polymer comprises at least one of PET, PLA and PEEK; (j) the crystalline polymer comprises at least one of PE, PP and PA; (k) the thermoplastic elastomer comprises at least one of EVA, TPE, TPU, TPEE and PEBA; (l) the fluid foaming agent comprises at least one of CO2, N2, n-pentane, isopentane, butane and Freon; (m) The solid foaming agent comprises at least one of expandable microspheres, carbonates, azodicarbonamide, and N,N-dinitrosopentamethylenetetramine.

7. The method for preparing the polymer porous foamed fiber according to claim 6, characterized in that: The hardness of the thermoplastic elastomer is Shore A20 to Shore A70.

8. The method for preparing the polymer porous foamed fiber according to claim 5, characterized in that: In step S1, when the foaming agent in the polymer particles containing the foaming agent is a fluid foaming agent, the fluid foaming agent is blended with the polymer particles by high pressure impregnation to obtain the polymer particles containing the foaming agent, and the high pressure impregnation is performed at 5 to 30 MPa.

9. The polymer porous foamed fiber prepared by the preparation method according to any one of claims 1 to 8.

10. Application of the polymer porous foamed fiber according to claim 9 in outdoor sports shoes and clothing, electronic wearable devices, functional clothing, and catalysis fields.

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