A moisture-absorbing and sweat-evaporating composite profiled polyamide 6 fiber, its preparation method and application

Abstract

The present invention belongs to the technical field of functional fibers, and discloses a moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber, a preparation method thereof, and an application thereof. The cross-section of the skin layer of the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber is in a "three-leaf" shape, a "cross" shape or a "five-leaf" shape, and the cross-section of the core layer is circular; the preparation method is as follows: taking polyamide 6 chips as the core layer raw material and polyamide 6 moisture-absorbing and sweat-releasing masterbatch as the skin layer raw material, after forming fibers by a skin-core composite spinning process, the fibers are successively soaked in a weak acid bath, a weak base bath and a water bath, and after taking out, they are dried to obtain the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber; the polyamide 6 moisture-absorbing and sweat-releasing masterbatch is obtained by taking polyamide 6 chips, boron nitride and calcium carbonate as raw materials, blending them and then melt-extruding and pelletizing them by a twin-screw extruder; the application is as follows: the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber prepared as described above can be woven into a fabric. The present invention ensures the mechanical properties of the fiber while improving the moisture-conducting and sweat-releasing properties of the fiber, and can meet the sweat-releasing requirements of the human body after strenuous exercise.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional fibers, and relates to a moisture-absorbing and sweat-wicking composite profiled polyamide 6 fiber, a preparation method thereof, and an application thereof. Background Art

[0002] Polyamide, also widely known as "nylon", stands out among many synthetic fibers with its high strength, excellent wear resistance, and good elasticity. Its wear resistance is particularly prominent, making polyamide fabrics extremely durable. At the same time, polyamide also exhibits good elasticity and recoverability. Although it is prone to deformation under external forces, it can quickly return to its original shape during wearing, which makes it widely used in the field of sports equipment. Whether it is sportswear or sports shoes, polyamide fibers are often seen.

[0003] However, the moisture-absorbing and sweat-wicking performance of polyamide is relatively weak. Especially after intense exercise or competition, the wearer may feel stuffy and uncomfortable. To improve this situation, the industry often uses the method of spinning profiled fibers with a profiled spinneret, such as "T" shape, "Y" shape, "cross" shape, or "five-leaf" shape, etc., to enhance the moisture-absorbing and sweat-wicking ability of polyamide.

[0004] The patent application with publication number CN102677215A discloses an antibacterial and moisture-conducting polyamide 6 and a preparation method thereof. The preparation method is to spin polyamide 6 fibers with a profiled cross-section to achieve the purpose of improving the moisture-absorbing and sweat-wicking effect. However, unfortunately, relying solely on the design of the profiled cross-section, the improvement of its moisture-absorbing and sweat-wicking performance is still limited and difficult to meet the sweating needs of the human body during intense exercise, especially in sports competitions.

[0005] The patent application with publication number CN113337910A discloses a white graphene moisture-absorbing and sweat-wicking ice-cold polyamide staple fiber and a preparation method thereof. The preparation method is to directly spin "cross"-shaped staple fibers by granulating boron nitride and polyamide 6, and the maximum addition amount of boron nitride can reach 14 wt%. However, due to the large filling of boron nitride, this method is only applicable to spinning polyamide 6 staple fibers, and the mechanical properties of the obtained fibers are poor. Although the addition of boron nitride increases the evaporation rate of sweat, the capillary action of conventional "cross" staple fibers on sweat is limited, so the improvement of the moisture-absorbing and sweat-wicking effect is not significant.

[0006] The patent application with the publication number CN105332089A discloses a preparation method of a moisture-absorbing and sweat-releasing functional polyester fiber. The preparation method is to add a high-concentration calcium carbonate masterbatch during the spinning process and prepare porous "cross-shaped" polyester fibers through acid reaction after spinning, thereby improving the moisture-absorbing and sweat-releasing performance of the fibers. However, this method also has the problem that the mechanical properties of the fibers decrease due to the addition of a large amount of calcium carbonate. Although creating pores on the fiber surface enhances its capillary action on sweat, generally speaking, the improvement of the moisture-absorbing and sweat-releasing effect is still limited.

[0007] Therefore, it is of great significance to study a moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber and its preparation method and application to solve the above problems. Summary of the Invention

[0008] The object of the present invention is to solve the problems existing in the prior art and provide a moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber and its preparation method and application.

[0009] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] A preparation method of a moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber, using polyamide 6 chips as the core layer raw material and polyamide 6 moisture-absorbing and sweat-releasing masterbatch as the skin layer raw material. After forming the fiber by the skin-core composite spinning process, the fiber is successively immersed in a weak acid bath, a weak base bath and a clear water bath, and then taken out and dried to obtain the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber;

[0011] The pH value of the weak acid bath is greater than 5 and less than 7, and the temperature is 30 - 50 °C; the pH value of the weak base bath is greater than 7 and less than 9, and the temperature is 30 - 50 °C; the pH value of the water bath is 7, and the temperature is 30 - 50 °C; Weak acid bath: A temperature in the range of 30 - 50 °C is conducive to the dissolution and removal of reaction products. For example, when using an acetic acid bath, within this temperature range, the degree of ionization of acetic acid is relatively appropriate, which can better react with residual substances such as calcium salts to form soluble acetates and be removed. At the same time, an appropriate temperature can endow the fiber molecular chain segments with a certain degree of activity, which is beneficial to the adjustment of the fiber structure. If the temperature is too low, the reaction rate will be very slow, and the efficiency of removing impurities will be low; too high a temperature may cause damage to the fiber because some properties of the fiber (such as strength, elasticity, etc.) may deteriorate under the combined action of high temperature and acidic environment. Weak base bath: Taking an ammonia water bath as an example, at 30 - 50 °C, the ionization equilibrium of ammonia water is conducive to the reaction of OH⁻ ions with residual acid radical ions, etc. For example, at this temperature, it can better neutralize the acidic substances remaining on the fiber surface to generate water and corresponding salts, thereby cleaning the fiber surface. Moreover, an appropriate temperature can make the interaction between the weak base and the fiber more effective, which is helpful for improving properties such as the feel of the fiber. If the temperature is too low, the reaction between the alkali solution and impurities is insufficient; too high a temperature may cause changes in the chemical structure of the fiber, such as hydrolysis, etc., and at the same time increase energy consumption. Water bath: The water bath at 30 - 50 °C is mainly used for cleaning. This temperature is slightly higher than room temperature, which can accelerate the diffusion rate of the substances remaining on the fiber surface, making the cleaning more thorough. Because as the temperature increases, the molecular motion speeds up. Whether it is the impurity molecules on the fiber surface or the solvent molecules in the water, their motion speeds increase, which is more conducive to the impurities entering the water from the fiber surface and being carried away.

[0012] Considering the physical properties of the fiber, treating the fiber in a bath solution at 30 - 50 °C can keep the fiber in good dimensional stability. Within this temperature range, the fiber will not shrink or expand excessively due to too high a temperature, ensuring that the shape and size of the fiber remain basically unchanged. If the temperature exceeds this range, it may cause phenomena such as thermal shrinkage of the fiber, changing the physical properties of the fiber and affecting subsequent use. At the same time, this temperature range helps to maintain the flexibility of the fiber. For most fibers, too low a temperature will make the fiber brittle, and too high a temperature may cause the fiber to lose its elasticity. After being treated in a bath solution at 30 - 50 °C, the fiber can maintain good flexibility, which is very important for textile processing (such as weaving, knitting, etc.) and the use performance of the final product (such as wearing comfort).

[0013] The polyamide 6 moisture management masterbatch is prepared by melt - extruding and pelletizing the blend of polyamide 6 chips, boron nitride, and calcium carbonate through a twin - screw extruder.

[0014] After being treated in a weak acid bath, the weak acid reacts with a large amount of calcium carbonate on the fiber surface, leaving micropores, which greatly increases the specific surface area of the profiled fiber, thereby enhancing the moisture absorption and sweat discharge effect. The polyamide 6 masterbatch containing calcium carbonate and boron nitride is added to the fiber cortex. The masterbatch is extruded by twin-screw melting and dispersion, so boron nitride can be evenly dispersed around calcium carbonate. And because boron nitride has a heat conduction effect, the heat transfer inside the fiber is more efficient, and finally the number and uniformity of micropores increase significantly.

[0015] As a preferred technical solution:

[0016] For the preparation method of a moisture-absorbing and sweat-discharging composite profiled polyamide 6 fiber as described above, the mass ratio of the cortex raw material to the core layer raw material is 10-30:70-90.

[0017] For the preparation method of a moisture-absorbing and sweat-discharging composite profiled polyamide 6 fiber as described above, the spinning process parameters are: spinning temperature 240-270 °C, spinning speed 4500-6000 m / min, side blowing temperature 15-25 °C, side blowing speed 0.3-0.8 m / s, oiling rate 0.6-1.2%.

[0018] For the preparation method of a moisture-absorbing and sweat-discharging composite profiled polyamide 6 fiber as described above, the weak acid bath is an acetic acid bath, a citric acid bath or a formic acid bath, and the fiber is soaked in the weak acid bath for 10-30 s;

[0019] The weak base bath is an ammonia water bath, a sodium bicarbonate bath or a triethanolamine bath, and the fiber is soaked in the weak base bath for 10-30 s;

[0020] The fiber is soaked in the water bath for 60-120 s;

[0021] The drying temperature is 80-100 °C.

[0022] For the preparation method of a moisture-absorbing and sweat-discharging composite profiled polyamide 6 fiber as described above, the specific preparation process of the polyamide 6 moisture absorption and discharge masterbatch is: according to the mass fraction, 72-90 parts of polyamide 6 chips, 5-10 parts of boron nitride, 5-15 parts of calcium carbonate and 0-3 parts of dispersant are put into a high-speed mixer and mixed evenly. The evenly mixed material is added to a twin-screw extruder for melt extrusion and pelletization to obtain the polyamide 6 moisture absorption and discharge masterbatch.

[0023] For the preparation method of a moisture-absorbing and sweat-discharging composite profiled polyamide 6 fiber as described above, the rotation speed of the high-speed mixer is 500-1000 rpm, and the mixing time is 5-20 min; the extrusion temperature is 200-270 °C.

[0024] For the preparation method of a moisture-absorbing and sweat-discharging composite profiled polyamide 6 fiber as described above, the average sheet diameter of boron nitride is 1-2 μm, and the thickness is 10 nm;

[0025] The average particle size of calcium carbonate is 80 nm;

[0026] The dispersant is one or more of ethylene bisstearamide, ethylene acrylic acid copolymer, and zinc salt ionomer copolymerized from ethylene and acrylic acid.

[0027] The present invention also provides a moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber prepared by the method described in any one of the above. The cross-section of the skin layer is in the shape of "three leaves", "cross", or "five leaves", and the cross-section of the core layer is circular.

[0028] As a preferred technical solution:

[0029] For the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber described above, the breaking strength is 3.70 - 3.75 cN / tex, the number of micropores per unit area (2 μm × 2 μm) on the fiber surface is 80 - 120, and the deviation of the micropore size does not exceed 10%.

[0030] The present invention also provides an application of the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber described in any one of the above, which is used to weave into a fabric; after the fiber is formed by the skin-core composite spinning process, the fiber can be made into a fabric first, and then the fabric is soaked in a weak acid bath, a weak base bath, and a water bath in sequence, and the treatment efficiency is relatively higher;

[0031] The water absorption rate of the fabric is 270 - 290%, the water droplet diffusion time is 0.2 - 0.6 s, the wicking height is 180 - 220 mm, and the drying rate is 0.8 - 1.3 g / h.

[0032] Principle of the invention:

[0033] The moisture-absorbing and sweat-venting composite profiled polyamide 6 fiber of the present invention has a circular cross-section in the core layer and is added with conventional polyamide 6 chips, which can play a role in supporting and improving spinnability and ensure the mechanical properties of the fiber; the cross-section of the skin layer is profiled and can be added with a high-concentration moisture-absorbing and sweat-venting masterbatch. The skin layer of the fiber is added with a polyamide 6 masterbatch containing calcium carbonate and boron nitride. The masterbatch is extruded by twin-screw melting and dispersion, so boron nitride can be evenly dispersed around calcium carbonate; the addition of boron nitride significantly enhances the heat conduction ability of the fiber, making the heat transfer inside the fiber more efficient. Therefore, when the fiber after spinning and forming is immersed in a weak acid bath, the heat transfer of the weak acid bath is more uniform, so that the contact reaction between the acid and calcium carbonate is more sufficient and uniform, avoiding the uneven reaction caused by too high or too low local temperature. Thus, on the one hand, the reaction time can be greatly shortened without changing other conditions, the fiber pore-forming efficiency is higher, and the number of micropores per unit area on the fiber surface can be greatly increased. The more micropores there are, the faster the diffusion and evaporation rate of moisture, and the better the moisture-absorbing and sweat-venting performance; on the other hand, the generated pores are more similar in size, and the uniformity of the pores is significantly improved, greatly enhancing the wicking effect of the fiber on sweat (the reason why the improvement of the pore uniformity can enhance the wicking effect is as follows: 1. Stability of the liquid transmission path: When the micropores on the fiber surface are more uniform, the liquid transmission path on the fiber surface is more regular and stable. This is like transporting liquid in a well-planned pipeline system. The liquid can be transported in a relatively stable manner along the uniformly distributed micropores and fiber gaps. For example, in some functional fibers for sportswear, if the micropores are uniform, sweat can quickly be transported from the skin surface to the outer layer of the fabric along these uniform channels, thus keeping the skin dry. 2. Avoiding local accumulation: Uniform micropores can prevent the local accumulation of liquid on the fiber surface. If the micropores are not uniform, the liquid may accumulate in areas with larger or more micropores, and it is difficult to transport in areas with smaller or fewer micropores. This is like in a system with uneven heights and different pipe diameters, where the liquid is likely to accumulate in low-lying areas or thick pipes. And uniform micropores can make the liquid evenly distributed on the fiber surface, ensuring that the wicking process can proceed efficiently. Therefore, the more uniform the micropores on the fiber surface, the better the wicking effect usually is).

[0034] Therefore, through this special design of the present invention, both the mechanical properties of the fiber are ensured and the moisture-conducting and sweat-venting performance of the fiber is greatly improved, meeting the sweating requirements of the human body after strenuous exercise.

[0035] Beneficial effects:

[0036] (1) By using polyamide 6 chips as the core layer raw material and designing the cross-section of the core layer of the fiber to be circular, the present invention can play a role in supporting and improving spinnability to ensure the mechanical properties of the fiber.

[0037] (2) The cortex cross-section of the fiber of the present invention is irregular. Using polyamide 6 moisture absorption and discharge masterbatch as raw material, the polyamide 6 moisture absorption and discharge masterbatch is extruded by twin-screw melting and dispersion, which can make boron nitride evenly dispersed around calcium carbonate, significantly enhancing the heat conduction ability of the fiber, making the heat transfer inside the fiber more efficient. As a result, when the fiber after spinning and forming is immersed in a weak acid bath, the heat transfer of the weak acid bath is more uniform, avoiding the uneven reaction caused by too high or too low local temperature. Finally, the number of micropores per unit area on the fiber surface is greatly increased and the size of the pores is more uniform, and the wicking effect on sweat is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic cross-sectional view of the moisture-absorbing and sweat-discharging composite irregular polyamide 6 fiber prepared in Example 1 of the present invention;

[0039] Figure 2 It is a schematic cross-sectional view of the moisture-absorbing and sweat-discharging composite irregular polyamide 6 fiber prepared in Example 2 of the present invention;

[0040] Figure 3 It is a schematic cross-sectional view of the moisture-absorbing and sweat-discharging composite irregular polyamide 6 fiber prepared in Example 3 of the present invention;

[0041] Among them, 1 - cortex, 2 - core layer. DETAILED DESCRIPTION OF THE INVENTION

[0042] The present invention will be further described below in conjunction with the specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0043] To ensure that the performance of the substances used in each embodiment and comparative example is disclosed sufficiently, the manufacturers and grades of the substances are stated. Products of other manufacturers and grades that meet the limitations of the present invention are also feasible.

[0044] The test methods for the relevant performance indexes in the following embodiments and comparative examples are as follows:

[0045] Tensile strength: Refer to the standard of GB / T 14344-2022 "Test Method for Tensile Properties of Chemical Fibers - Filament Yarns" to test the tensile strength of the fibers prepared in each embodiment and each comparative example.

[0046] Water absorption rate, water droplet diffusion time, capillary rise height, and drying rate: Refer to the standard of GB / T 21655.1-2023 "Evaluation of moisture absorption and quick drying properties of textiles - Part 1: Single combination test method" to test the water absorption rate, water droplet diffusion time, capillary rise height, and drying rate of the fabrics prepared in each example and each comparative example.

[0047] Example 1

[0048] A method for preparing a moisture-absorbing and sweat-wicking composite profiled polyamide 6 fiber is as follows:

[0049] (1) Prepare polyamide 6 moisture-absorbing and sweat-wicking masterbatch;

[0050] According to the mass parts, 79 parts of polyamide 6 chips (manufacturer: Guangdong Hengshen Meida New Materials Co., Ltd., grade: M2400), 10 parts of boron nitride (average sheet diameter: 1 μm, thickness: 10 nm), 10 parts of calcium carbonate (average particle size: 80 nm), and 1 part of dispersant (ethylene bisstearamide) are put into a high-speed mixer and mixed evenly. The evenly mixed materials are added to a twin-screw extruder for melt extrusion granulation to obtain polyamide 6 moisture-absorbing and sweat-wicking masterbatch; among them, the rotation speed of the high-speed mixer is 800 rpm, and the mixing time is 10 min; the temperature of the first zone in the twin-screw extruder is 240 °C, the temperature of the second zone is 270 °C, the temperature of the third zone is 270 °C, the temperature of the fourth zone is 270 °C, the temperature of the fifth zone is 260 °C, the temperature of the sixth zone is 260 °C, the temperature of the seventh zone is 240 °C, the temperature of the eighth zone is 200 °C, the temperature of the ninth zone is 200 °C, the temperature of the tenth zone is 200 °C, the temperature of the eleventh zone is 220 °C, and the temperature of the twelfth zone is 250 °C;

[0051] (2) Use polyamide 6 chips (manufacturer: Guangdong Hengshen Meida New Materials Co., Ltd., grade: M2400) as the core layer raw material, and polyamide 6 moisture-absorbing and sweat-wicking masterbatch as the skin layer raw material, and use the skin-core composite spinning process to form fibers; among them, the mass ratio of the skin layer raw material to the core layer raw material is 10:90;

[0052] The spinning process parameters are: spinning temperature 270 °C, spinning speed 4500 m / min, side blowing temperature 15 °C, side blowing speed 0.4 m / s, oiling rate 0.6%;

[0053] (3) Immerse the fibers obtained in step (2) in a citric acid solution at 30 °C with a pH value of 6 for 20 s, then immerse them in a sodium bicarbonate solution at 30 °C with a pH value of 8 for 20 s, and finally immerse them in a water bath at 30 °C with a pH value of 7 for 100 s. After taking them out, dry them at 80 °C to obtain moisture-absorbing and sweat-wicking composite profiled polyamide 6 fibers.

[0054] As Figure 1As shown, the cross-section of the skin layer 1 of the finally prepared moisture-absorbing and sweat-dispersing composite profiled polyamide 6 fiber is "three-leaf" shaped, and the cross-section of the core layer 2 is circular; the breaking strength of the moisture-absorbing and sweat-dispersing composite profiled polyamide 6 fiber is 3.71 cN / tex, the number of micropores per unit area (2μm×2μm) on the fiber surface is 81, and the deviation of the micropore size is 6%.

[0055] The above-prepared moisture-absorbing and sweat-dispersing composite profiled polyamide 6 fiber is made into a fabric by weft knitting process;

[0056] The finally prepared fabric has a warp density of 100 picks per inch, a weft density of 80 picks per inch, a water absorption rate of 280%, a water droplet diffusion time of 0.6 s, a wicking height of 185 mm, and a drying rate of 0.82 g / h.

[0057] Comparative Example 1

[0058] A method for preparing profiled polyamide 6 fiber is basically the same as that in Example 1, except that: step (1) is not carried out, in step (2), only polyamide 6 chips are used as raw materials, and the fiber is prepared by using a conventional spinning component, and the fiber used in step (3) is the one prepared in this comparative example.

[0059] The number of micropores per unit area (2μm×2μm) on the surface of the finally prepared profiled polyamide 6 fiber is 0.

[0060] The above-prepared profiled polyamide 6 fiber is woven into a fabric, and the preparation process is basically the same as that in Example 1, except that: the fiber used is the profiled polyamide 6 fiber prepared in this comparative example.

[0061] The finally prepared fabric has a water absorption rate of 141%, a water droplet diffusion time of 3.1 s, a wicking height of 106 mm, and a drying rate of 0.35 g / h.

[0062] Comparing Comparative Example 1 with Example 1, it can be seen that the moisture-absorbing and sweat-dispersing performance of the fabric prepared in Comparative Example 1 has decreased significantly. This is because although Comparative Example 1 spun profiled polyamide 6 fiber in the same way as Example 1, a large number of micropores were formed on the fiber surface in Example 1, greatly increasing the specific surface area of the fiber, thereby improving the moisture-absorbing and sweat-dispersing performance of the fabric.

[0063] Comparative Example 2

[0064] A method for preparing profiled polyamide 6 fiber is basically the same as that in Example 1, except that: in step (2), polyamide 6 chips and the polyamide 6 moisture-absorbing and sweat-dispersing masterbatch prepared in step (1) are directly mixed to prepare the fiber.

[0065] The breaking strength of the finally prepared profiled polyamide 6 fiber is 2.79 cN / tex, the number of micropores per unit area (2μm×2μm) on the fiber surface is 67, and the deviation of the micropore size is 10%.

[0066] Weave the obtained profiled polyamide 6 fibers into a fabric. The preparation process is basically the same as that in Example 1, except that: the fibers used are the profiled polyamide 6 fibers prepared in this comparative example.

[0067] The water absorption rate of the finally obtained fabric is 252%, the water droplet diffusion time is 1.5 s, the wicking height is 162 mm, and the drying rate is 0.61 g / h.

[0068] Comparing Comparative Example 2 with Example 1, it can be seen that the breaking strength and the number of micropores of the profiled polyamide 6 fibers prepared in Comparative Example 2 decrease, and the moisture absorption and sweat discharge performance of the fabric prepared therefrom is poor. This is because in Comparative Example 2, polyamide 6 chips and polyamide 6 moisture absorption and sweat discharge masterbatch are directly mixed and spun, which will make the polyamide 6 moisture absorption and sweat discharge masterbatch evenly distributed inside the whole fiber. However, the carrier resin in the polyamide 6 moisture absorption and sweat discharge masterbatch distributed inside the fiber undergoes serious degradation after being subjected to the second high-temperature processing, resulting in a very wide molecular weight distribution of the polyamide 6 resin in the whole polyamide 6 fiber, greatly reducing the breaking strength of the whole polyamide 6 fiber. In addition, since in Comparative Example 2, the polyamide 6 moisture absorption and sweat discharge masterbatch is evenly added to the whole fiber, the calcium carbonate and boron nitride therein are also evenly distributed in the whole fiber, while the calcium carbonate and boron nitride in Example 1 are only distributed in the cortical fiber part. Therefore, under the condition that the fiber thickness and shape are the same, theoretically, the method of adding the polyamide 6 moisture absorption and sweat discharge masterbatch to the whole fiber results in less boron nitride and calcium carbonate on the fiber surface, leading to a decrease in the number of surface micropores and a decrease in the specific surface area of the obtained moisture absorption and sweat discharge composite profiled polyamide 6 fibers, and further resulting in a greater decrease in the moisture absorption and sweat discharge effect of the fabric prepared therefrom.

[0069] Comparative Example 3

[0070] A preparation method of a composite profiled polyamide 6 fiber is basically the same as that in Example 1, except that: the calcium carbonate in step (1) is replaced by boron nitride of the same mass.

[0071] The number of micropores per unit area (2 μm × 2 μm) on the surface of the finally obtained composite profiled polyamide 6 fiber is 0.

[0072] Weave the obtained composite profiled polyamide 6 fibers into a fabric. The preparation process is basically the same as that in Example 1, except that: the fibers used are the composite profiled polyamide 6 fibers prepared in this comparative example.

[0073] The water absorption rate of the finally obtained fabric is 193%, the water droplet diffusion time is 2.2 s, the wicking height is 115 mm, and the drying rate is 0.43 g / h.

[0074] Comparing Comparative Example 3 with Example 1, it can be seen that the number of micropores per unit area on the surface of the composite profiled polyamide 6 fiber prepared in Comparative Example 3 is 0, and the moisture absorption and sweat discharge effect of the fabric prepared therefrom decreases. This is because calcium carbonate was not introduced into the fiber cortex in Comparative Example 3, resulting in no micropores on the surface of the prepared composite profiled polyamide 6 fiber, its specific surface area is relatively low, and the moisture absorption and sweat discharge effect of the fabric prepared therefrom decreases significantly.

[0075] Comparative Example 4

[0076] A method for preparing a composite profiled polyamide 6 fiber is basically the same as that in Example 1, except that: boron nitride in step (1) is replaced with calcium carbonate of the same mass.

[0077] Finally, the number of micropores per unit area (2μm×2μm) on the surface of the prepared composite profiled polyamide 6 fiber is 42, and the deviation of the micropore size is 53%.

[0078] Weave the above-prepared composite profiled polyamide 6 fiber into a fabric. The preparation process is basically the same as that in Example 1, except that: the fiber used is the composite profiled polyamide 6 fiber prepared in this comparative example.

[0079] Finally, the water absorption rate of the prepared fabric is 204%, the water droplet diffusion time is 2 s, the wicking height is 120 mm, and the drying rate is 0.45 g / h.

[0080] Comparing Comparative Example 4 with Example 1, it can be seen that the number of micropores per unit area on the surface of the composite profiled polyamide 6 fiber prepared in Comparative Example 4 decreases, and the deviation of the micropore size increases significantly. The moisture absorption and sweat discharge performance of the fabric prepared therefrom decreases. This is because boron nitride has thermal conductivity, and boron nitride was not introduced into the fiber cortex in Comparative Example 4, which will cause the heat transfer to be slower when the composite profiled polyamide 6 fiber prepared in this comparative example is soaked in a weak acid bath, resulting in problems of local temperature being too low or too high, and uneven reaction, thus leading to a decrease in the number of micropores per unit area and a significant increase in the deviation of the micropore size, and the moisture absorption and sweat discharge performance of the fabric prepared therefrom decreases significantly.

[0081] Example 2

[0082] A method for preparing a moisture absorption and sweat discharge composite profiled polyamide 6 fiber is as follows:

[0083] (1) Prepare a polyamide 6 moisture absorption and drainage masterbatch;

[0084] According to the parts by mass, 72 parts of polyamide 6 chips (manufactured by Guangdong Hengshen Meida New Materials Co., Ltd., grade M2400), 10 parts of boron nitride (average sheet diameter 1.5 μm, thickness 10 nm), 15 parts of calcium carbonate (average particle size 80 nm), and 3 parts of ethylene acrylic copolymer (manufactured by Honeywell International Inc., model Honeywell ethylene-acrylic (EAA) copolymer wax powder A-C® 580) are put into a high-speed mixer and mixed evenly. The evenly mixed material is added to a twin-screw extruder for melt extrusion granulation to obtain polyamide 6 moisture-absorbing and sweat-releasing masterbatch. Among them, the rotation speed of the high-speed mixer is 1000 rpm, and the mixing time is 20 min. The temperature of the first zone in the twin-screw extruder is 240 °C, the second zone is 270 °C, the third zone is 270 °C, the fourth zone is 270 °C, the fifth zone is 260 °C, the sixth zone is 260 °C, the seventh zone is 240 °C, the eighth zone is 200 °C, the ninth zone is 200 °C, the tenth zone is 200 °C, the eleventh zone is 220 °C, and the twelfth zone is 250 °C;

[0085] (2) Using polyamide 6 chips (manufactured by Guangdong Hengshen Meida New Materials Co., Ltd., grade M2400) as the core layer raw material and polyamide 6 moisture-absorbing and sweat-releasing masterbatch as the skin layer raw material, fibers are formed by a skin-core composite spinning process. Among them, the mass ratio of the skin layer raw material to the core layer raw material is 30:70;

[0086] The spinning process parameters are: spinning temperature 270 °C, spinning speed 4500 m / min, side blowing temperature 15 °C, side blowing speed 0.3 m / s, and oiling rate 0.6%;

[0087] (3) The fibers obtained in step (2) are first soaked in a citric acid solution at 40 °C and pH 5.5 for 30 s, then soaked in a sodium bicarbonate solution at 40 °C and pH 8.5 for 30 s, and finally soaked in a water bath at 50 °C and pH 7 for 60 s. After taking out, they are dried at 80 °C to obtain moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers.

[0088] As Figure 2 shown, the cross-section of the skin layer 1 of the finally obtained moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers is in a "cross" shape, and the cross-section of the core layer 2 is circular; the breaking strength of the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers is 3.73 cN / tex, the number of micropores per unit area (2 μm × 2 μm) on the fiber surface is 120, and the deviation of the micropore size is 7%.

[0089] The above-mentioned obtained moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers are made into a fabric by a weft knitting process.

[0090] The warp density of the finally obtained fabric is 110 threads per inch, the weft density is 90 threads per inch, the water absorption rate is 275%, the water droplet diffusion time is 0.5 s, the wicking height is 183 mm, and the drying rate is 0.81 g / h.

[0091] Example 3

[0092] A preparation method of a moisture-absorbing and sweat-evaporating composite profiled polyamide 6 fiber is as follows:

[0093] (1) Prepare polyamide 6 moisture-absorbing and sweat-evaporating masterbatch;

[0094] According to mass parts, 85.5 parts of polyamide 6 chips (manufacturer: Guangdong Hengshen Meida New Materials Co., Ltd., grade: M2400), 8 parts of boron nitride (average sheet diameter: 1 μm, thickness: 10 nm), 5 parts of calcium carbonate (average particle size: 80 nm), and 1.5 parts of zinc salt ionomer copolymerized with ethylene acrylic acid (manufacturer: Honeywell International Inc., model: Honeywell AClyn® 295A) are put into a high-speed mixer and mixed evenly. The evenly mixed materials are added to a twin-screw extruder for melt extrusion and pelletizing to obtain polyamide 6 moisture-absorbing and sweat-evaporating masterbatch; among them, the rotation speed of the high-speed mixer is 500 rpm, and the mixing time is 5 min; the temperature of the first zone in the twin-screw extruder is 240 °C, the temperature of the second zone is 270 °C, the temperature of the third zone is 270 °C, the temperature of the fourth zone is 270 °C, the temperature of the fifth zone is 260 °C, the temperature of the sixth zone is 260 °C, the temperature of the seventh zone is 240 °C, the temperature of the eighth zone is 200 °C, the temperature of the ninth zone is 200 °C, the temperature of the tenth zone is 200 °C, the temperature of the eleventh zone is 220 °C, and the temperature of the twelfth zone is 250 °C;

[0095] (2) Use polyamide 6 chips (manufacturer: Guangdong Hengshen Meida New Materials Co., Ltd., grade: M2400) as the core layer raw material, and polyamide 6 moisture-absorbing and sweat-evaporating masterbatch as the skin layer raw material, and use the skin-core composite spinning process to form fibers; among them, the mass ratio of the skin layer raw material to the core layer raw material is 20:80;

[0096] The spinning process parameters are: spinning temperature 270 °C, spinning speed 6000 m / min, side blowing temperature 25 °C, side blowing speed 0.8 m / s, oiling rate 1.2%;

[0097] (3) Immerse the fibers obtained in step (2) in a formic acid solution at 50 °C and pH 5.8 for 10 s, then immerse them in a triethanolamine solution at 50 °C and pH 8.2 for 10 s, and finally immerse them in a water bath at 30 °C and pH 7 for 120 s. After taking them out, dry them at 90 °C to obtain moisture-absorbing and sweat-evaporating composite profiled polyamide 6 fibers.

[0098] As Figure 3As shown, the cross-section of the skin layer 1 of the finally obtained moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber is "five-leaf" shaped, and the cross-section of the core layer 2 is circular; the breaking strength of the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber is 3.72 cN / tex, the number of micropores per unit area (2μm×2μm) on the fiber surface is 80, and the deviation of the micropore size is 5%.

[0099] The above-prepared moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber is made into a fabric by weft knitting process.

[0100] The warp density of the finally obtained fabric is 125 threads per inch, the weft density is 100 threads per inch, the water absorption rate is 270%, the water droplet diffusion time is 0.4 s, the wicking height is 180 mm, and the drying rate is 0.8 g / h.

[0101] Example 4

[0102] A preparation method of a moisture-absorbing and sweat-releasing composite profiled polyamide 6 fiber comprises the following steps:

[0103] (1) Prepare polyamide 6 moisture-absorbing and sweat-releasing masterbatch;

[0104] According to mass parts, 81 parts of polyamide 6 chips (manufacturer: Guangdong Hengshen Meida New Materials Co., Ltd., grade: M2400), 10 parts of boron nitride (average sheet diameter: 2μm, thickness: 10nm), 8 parts of calcium carbonate (average particle diameter: 80nm) and 1 part of dispersant (a mixture of ethylene bisstearamide and ethylene acrylic copolymer with a mass ratio of 1:1, the manufacturer of the ethylene acrylic copolymer is Honeywell International Inc., model: Honeywell ethylene-acrylic (EAA) copolymer wax powder A-C® 580) are put into a high-speed mixer and mixed evenly. The evenly mixed materials are added into a twin-screw extruder for melt extrusion granulation to obtain the polyamide 6 moisture-absorbing and sweat-releasing masterbatch; wherein, the rotation speed of the high-speed mixer is 500 rpm, and the mixing time is 10 min; the temperature of the first zone in the twin-screw extruder is 240°C, the temperature of the second zone is 270°C, the temperature of the third zone is 270°C, the temperature of the fourth zone is 270°C, the temperature of the fifth zone is 260°C, the temperature of the sixth zone is 260°C, the temperature of the seventh zone is 240°C, the temperature of the eighth zone is 200°C, the temperature of the ninth zone is 200°C, the temperature of the tenth zone is 200°C, the temperature of the eleventh zone is 220°C, and the temperature of the twelfth zone is 250°C;

[0105] (2) Using polyamide 6 chips (manufacturer: Guangdong Hengshen Meida New Materials Co., Ltd., grade: M2400) as the core layer raw material and polyamide 6 moisture-absorbing and sweat-releasing masterbatch as the skin layer raw material, form fibers by a skin-core composite spinning process; wherein, the mass ratio of the skin layer raw material to the core layer raw material is 10:90;

[0106] The spinning process parameters are as follows: spinning temperature is 270 °C, spinning speed is 5300 m / min, side blowing temperature is 20 °C, side blowing speed is 0.5 m / s, and oiling rate is 0.9%;

[0107] (3) Immerse the fibers obtained in step (2) in an acetic acid solution at 35 °C with a pH value of 6.5 for 20 s, then immerse them in an ammonia water solution at 35 °C with a pH value of 7.5 for 20 s, and finally immerse them in a water bath at 40 °C with a pH value of 7 for 90 s. After taking them out, dry them at 100 °C to obtain the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers.

[0108] The cross-section of the skin layer of the finally obtained moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers is in a "three-leaf" shape, and the cross-section of the core layer is circular; the breaking strength of the moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers is 3.75 cN / tex, the number of micropores per unit area (2 μm × 2 μm) on the fiber surface is 100, and the deviation of the micropore size is 4%.

[0109] The above-prepared moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers are made into a fabric by weft knitting technology.

[0110] The finally obtained fabric has a warp density of 140 picks per inch, a weft density of 110 picks per inch, a water absorption rate of 290%, a water droplet diffusion time of 0.6 s, a wicking height of 220 mm, and a drying rate of 1.3 g / h.

[0111] Example 5

[0112] A method for preparing moisture-absorbing and sweat-releasing composite profiled polyamide 6 fibers, the steps are as follows:

[0113] (1) Prepare polyamide 6 moisture-absorbing and sweat-releasing masterbatch;

[0114] According to mass parts, put 90 parts of polyamide 6 chips (manufacturer: Guangdong Hengshen Meida New Materials Co., Ltd., brand: M2400), 5 parts of boron nitride (average sheet diameter is 1.5 μm, thickness is 10 nm), and 5 parts of calcium carbonate (average particle size is 80 nm) into a high-speed mixer and mix evenly. The evenly mixed material is added to a twin-screw extruder for melt extrusion granulation to obtain polyamide 6 moisture-absorbing and sweat-releasing masterbatch; among them, the rotation speed of the high-speed mixer is 700 rpm, and the mixing time is 20 min; the temperature of the first zone in the twin-screw extruder is 240 °C, the temperature of the second zone is 270 °C, the temperature of the third zone is 270 °C, the temperature of the fourth zone is 270 °C, the temperature of the fifth zone is 260 °C, the temperature of the sixth zone is 260 °C, the temperature of the seventh zone is 240 °C, the temperature of the eighth zone is 200 °C, the temperature of the ninth zone is 200 °C, the temperature of the tenth zone is 200 °C, the temperature of the eleventh zone is 220 °C, and the temperature of the twelfth zone is 250 °C;

[0115] (2)Take polyamide 6 chips (manufactured by Guangdong Hengshen Meida New Materials Co., Ltd., grade M2400) as the core layer raw material and polyamide 6 moisture absorption and sweat discharge masterbatch as the skin layer raw material, and use the skin-core composite spinning process to form fibers; among them, the mass ratio of the skin layer raw material to the core layer raw material of the spinneret hole is 20:80;

[0116] The spinning process parameters are: spinning temperature 270 °C, spinning speed 6000 m / min, side blowing temperature 20 °C, side blowing speed 0.5 m / s, oiling rate 1.2%;

[0117] (3)Immerse the fibers obtained in step (2) in a formic acid solution at 40 °C and pH 6.3 for 10 s, then immerse them in a triethanolamine solution at 40 °C and pH 7.7 for 10 s, and finally immerse them in a water bath at 35 °C and pH 7 for 100 s. After taking them out, dry them at 100 °C to obtain moisture absorption and sweat discharge composite profiled polyamide 6 fibers.

[0118] The cross-section of the skin layer of the finally obtained moisture absorption and sweat discharge composite profiled polyamide 6 fibers is "five-leaf" shaped, and the cross-section of the core layer is circular; the breaking strength of the moisture absorption and sweat discharge composite profiled polyamide 6 fibers is 3.73 cN / tex, the number of micropores per unit area (2 μm × 2 μm) on the fiber surface is 92, and the deviation of the micropore size is 4%.

[0119] Use the above-mentioned obtained moisture absorption and sweat discharge composite profiled polyamide 6 fibers to make a fabric by weft knitting process.

[0120] The warp density of the finally obtained fabric is 150 ends per inch, the weft density is 120 picks per inch, the water absorption rate is 273%, the water droplet diffusion time is 0.2 s, the wicking height is 200 mm, and the drying rate is 1.1 g / h.

Claims

1. A method for preparing a moisture wicking composite shaped nylon 6 fiber, characterized in that: Nylon 6 slices are used as the core material, and nylon 6 moisture-wicking masterbatch is used as the skin material. After the fibers are formed by the skin-core composite spinning process, the fibers are sequentially soaked in a weak acid bath, a weak alkali bath, and a clean water bath, and then taken out and dried to obtain moisture-wicking composite special-shaped nylon 6 fibers. The pH value of the weak acid bath is greater than 5, and the temperature is 30-50°C; the pH value of the weak base bath is less than 9, and the temperature is 30-50°C; the pH value of the water bath is 7, and the temperature is 30-50°C; The weak acid bath is an acetic acid bath, a citric acid bath or a formic acid bath, and the fiber is immersed in the weak acid bath for 10 to 30 seconds; Nylon 6 suction and discharge masterbatch is made of nylon 6 chips, boron nitride and calcium carbonate as raw materials, which are blended and granulated by a twin-screw extruder. The number of micropores per unit area on the surface of the moisture wicking composite special-shaped nylon 6 fiber is 80 to 120, the deviation of the micropore size does not exceed 10%, and the unit area refers to 2μm×2μm.

2. The method for preparing a moisture wicking composite special-shaped nylon 6 fiber according to claim 1, characterized in that: The mass ratio of the skin layer raw material to the core layer raw material is 10-30:70-90.

3. The method for preparing a moisture wicking composite special-shaped nylon 6 fiber according to claim 1, characterized in that: The spinning process parameters are: spinning temperature 240-270°C, spinning speed 4500-6000m / min, side blowing temperature 15-25°C, side blowing speed 0.3-0.8m / s, and oiling rate 0.6-1.2%.

4. The method for preparing a moisture wicking composite special-shaped nylon 6 fiber according to claim 1, characterized in that: The weak alkali bath is an ammonia bath, a sodium bicarbonate bath or a triethanolamine bath, and the fiber is immersed in the weak alkali bath for 10 to 30 seconds; The fiber is immersed in the water bath for 60 to 120 seconds; The drying temperature is 80-100°C.

5. The method for preparing a moisture wicking composite special-shaped nylon 6 fiber according to claim 1, characterized in that: The specific preparation process of nylon 6 suction and discharge masterbatch is as follows: according to the mass proportions, 72 to 90 parts of nylon 6 chips, 5 to 10 parts of boron nitride, 5 to 15 parts of calcium carbonate and 0 to 3 parts of dispersant are put into a high-speed mixer and mixed evenly; the evenly mixed materials are added into a twin-screw extruder for melt extrusion granulation to obtain nylon 6 suction and discharge masterbatch.

6. The method for preparing a moisture wicking composite special-shaped nylon 6 fiber according to claim 5, characterized in that: The speed of the high speed mixer is 500-1000 rpm, the mixing time is 5-20 min, and the extrusion temperature is 200-270°C.

7. The method for preparing a moisture wicking composite special-shaped nylon 6 fiber according to claim 5, characterized in that: The average flake diameter of boron nitride is 1 to 2 μm and the thickness is 10 nm; The average particle size of calcium carbonate is 80nm; The dispersant is one or more of ethylene bisstearic acid amide, ethylene acrylic acid copolymer and ethylene acrylic acid copolymer zinc salt ionomer.

8. A moisture wicking composite shaped nylon 6 fiber prepared by the method according to any one of claims 1 to 7, characterized in that: The cross section of the cortex is "three-leaf", "cross" or "five-leaf", and the cross section of the core layer is circular.

9. The moisture wicking composite shaped nylon 6 fiber according to claim 8, characterized in that: The breaking strength of the moisture wicking composite shaped nylon 6 fiber is 3.70-3.75 cN / tex.

10. The use of a moisture wicking composite shaped nylon 6 fiber as claimed in claim 8 or 9, characterized in that: Used to weave fabrics; The water absorption rate of the fabric is 270-290%, the water drop diffusion time is 0.2-0.6s, the wicking height is 180-220mm, and the drying rate is 0.8-1.3g / h.

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