Silk-like fdy fiber and preparation method thereof

Abstract

This application discloses a silk-like FDY fiber and its preparation method. The method involves adding 1-3% by weight of modified zinc oxide whiskers to a polyester melt via an online addition system. The melt is then extruded from a spinning assembly to obtain monofilaments with a fineness of 0.5-1 dtex. These monofilaments are then sequentially cooled, oiled, pre-networked, hot-rolled, main-networked, and wound to obtain the silk-like FDY fiber. The hot-rolled rollers used for hot-rolling are HR1, HR2, HR3, HR4, and HR5. The temperatures of HR1, HR2, and HR3 are 82±2℃, and the temperatures of HR4 and HR5 are 132±2℃. The draw ratio between HR1 and HR2 is 1.01-1.06, between HR2 and HR3 is 1.08-1.12, and between HR3 and HR4 is 1.20-1.32. The silk-like FDY fiber of this application exhibits good dyeing performance, can be dyed in dark colors, and has high strength, with minimal fuzzing or breakage.

Description

Technical Field

[0001] This application relates to the field of polyester spinning, and in particular to a silk-like FDY fiber and its preparation method. Background Technology

[0002] Silk, as a classic textile material, is widely used in high-end clothing, home furnishings, painting, and embroidery due to its unique advantages such as its gorgeous luster, lightweight texture, smooth feel, and superior comfort. However, the silk industry faces numerous challenges. From a production perspective, the silk-making process is extremely complex and intricate. From silkworm cocoon farming to subsequent silk extraction, weaving, and dyeing, it requires not only a large workforce but also highly advanced technology, making it difficult to improve production efficiency. Simultaneously, the supply of raw materials is constrained by silkworm cocoon production. The farming process is easily affected by factors such as climate and pests, leading to significant fluctuations in the raw material market, further increasing production costs and ultimately resulting in persistently high silk prices. Furthermore, silkworm cocoon production itself is limited, exhibiting significant seasonal and regional restrictions, making it impossible to meet large-scale market demand, highlighting the problem of low production volume.

[0003] To meet market demand for silk-like products and address the numerous problems associated with silk, a manufacturing process using FDY (dimethylaminopropionate) synthetic fibers to imitate silk has emerged and matured. This process primarily achieves the silk-like effect through irregularly shaped cross-sections or fine denier fibers. By utilizing the triangular cross-section of silk fibers, which mimics the shape of silk, the fibers refract and disperse light like a prism, producing a silk-like sheen. Fine denier fibers, on the other hand, enhance the fiber's internal light-reflecting ability by increasing its layered structure, resulting in a more delicate luster in the fabric.

[0004] However, this silk-like technology also has certain limitations. The hue and depth of color after fiber dyeing depend on the light reflected from the surface and the light refracted within the fiber. Due to their greater surface reflectivity, irregularly shaped cross-section fibers and fine denier fibers will have lighter colors and lower dyeing density when dyed with the same amount of dye. To achieve a darker color, the amount of dye used must be increased, which not only increases production costs but may also lead to environmental problems. Summary of the Invention

[0005] To address the current problems of low dyeing performance and low dyeing rate of imitation silk FDY fibers, this application provides an imitation silk FDY fiber and its preparation method.

[0006] In one aspect, this application provides a method for preparing silk-like FDY fiber. The method involves adding 1-3% by weight of modified zinc oxide whiskers to a polyester melt via an online addition system. The melt is then extruded from a spinning assembly to obtain monofilaments with a fineness of 0.5-1 dtex. These monofilaments are then sequentially cooled, oiled, pre-networked, hot-rolled drawn and shaped, main-networked, and wound to obtain the silk-like FDY fiber. The aspect ratio of the alumina whiskers is 10-20. The hot roller drawing and setting process uses five sets of hot rollers, namely HR1, HR2, HR3, HR4, and HR5. The temperature of HR1, HR2, and HR3 is 82±2℃, the temperature of HR4 and HR5 is 132±2℃, the drawing ratio between HR1 and HR2 is 1.01 to 1.06, the drawing ratio between HR2 and HR3 is 1.08 to 1.12, and the drawing ratio between HR3 and HR4 is 1.20 to 1.32.

[0007] In any of the above technical solutions, the rotational speeds of HR1, HR2, and HR3 are 3080±20m / min, 3130±20m / min, and 3630±20m / min, respectively, and the rotational speeds of HR4 and HR5 are 4650±20m / min.

[0008] In any of the above technical solutions, the contact length between the fiber and the hot roller is 62 to 66% of the outer diameter of the hot roller.

[0009] After hot roller drawing and setting, the fiber orientation and crystallinity are high, and the macromolecules are arranged relatively neatly, making it difficult for dye molecules to penetrate and affecting the fiber's dyeing performance. This application effectively improves the fiber's dyeing performance by reducing the temperature of the HR1, HR2, and HR3 hot rollers and the draw ratio between the HR1, HR2, HR3, and HR4 rollers. Specifically, after the fiber is drawn by the HR1, HR2, and HR3 hot rollers, its orientation and crystallinity are lower, and gaps and channels for dye penetration are formed within the fiber, thus improving dyeing performance.

[0010] It is important to note that the temperatures of the HR1, HR2, and HR3 hot rollers must be above the glass transition temperature, i.e., above 68°C. Below this, lower temperatures are more beneficial for improving dyeing performance. However, if the temperature is too low, the molecular chain segments are inactive, and the filament bundle is prone to cold stretching, leading to uneven elongation or fuzzing. The speeds of the HR1, HR2, and HR3 hot rollers should be low to improve heating efficiency. The HR4 and HR5 hot rollers are used for setting; their temperatures primarily affect the boiling water shrinkage rate of the fiber. To meet the boiling water shrinkage rate requirements of silk products, the aforementioned setting temperatures are selected. The speed of the HR4 hot roller is basically the same as that of the HR5 hot roller, mainly serving to stabilize the tension between the two rollers, ensuring the filament bundle does not wobble on the hot rollers and increasing the setting time.

[0011] Insufficient drafting of the aforementioned fibers during the hot roller drafting process results in low orientation and crystallinity, leading to decreased breaking strength and elongation at break. Furthermore, due to the large specific surface area of ​​the silk-like fibers, the static electricity generated by friction with air is significant, causing the fibers to easily vibrate on the hot rollers during drafting, resulting in inconsistent contact areas between the fiber bundle and the hot rollers. These phenomena collectively contribute to increased fiber fuzz and breakage rates, affecting production efficiency and product yield. To address this, this application incorporates modified zinc oxide whiskers, which, when dispersed within the fibers, inhibit excessively tight molecular chain arrangement and form channels or gaps within the fibers, facilitating the entry of dye molecules into the fiber interior. Simultaneously, the whiskers align along the fiber extrusion direction, thereby improving fiber orientation and compensating for the strength loss caused by insufficient drafting. In addition, the addition of zinc oxide whiskers alleviates static electricity buildup caused by friction, which helps reduce fiber fuzz and breakage.

[0012] Furthermore, it should be noted that a zinc oxide whisker with a too large aspect ratio can easily cause fuzziness and breakage; while a too small aspect ratio has little effect on improving fiber dyeing performance. Adding conventional granular or spherical fillers, such as calcium carbonate, does not promote fiber orientation; instead, its strong inducing crystallization effect reduces dye penetration channels in the fiber, thus affecting the dyeing effect.

[0013] In any of the above technical solutions, the method for preparing the modified zinc oxide whiskers is as follows: zinc oxide whiskers with a mass ratio of 100:3 to 6 are mixed with an aminosilane coupling agent in ethanol, and the mixture is filtered, washed, and dried to obtain aminated whiskers; then, aminated whiskers with a mass ratio of 100:5 to 10 and carboxyl-terminated hyperbranched polyester are added to N,N-dimethylformamide and reacted at 100 to 120°C, and the mixture is filtered, washed, and dried to obtain the final product.

[0014] In any of the above technical solutions, the molecular weight of the end-carboxyl hyperbranched polyester is 1000-6000, and the carboxyl content (number of carboxyl groups) in the end-carboxyl hyperbranched polyester per unit molar mass is 6-24 moles.

[0015] To ensure the performance of zinc oxide whiskers, their uniform dispersion within the fiber is crucial. This application improves the compatibility of zinc oxide whiskers with polyester by grafting hyperbranched polyester onto the whisker surface, enabling the whiskers to be uniformly dispersed within the polyester matrix during melt blending. Furthermore, the terminal carboxyl groups in the terminal carboxyl hyperbranched polyester can form chemical bonds with the carboxyl groups in the polyester melt, contributing to improved fiber strength properties.

[0016] In any of the above technical solutions, the spinning assembly has a 400-mesh filter, an 80-100-mesh glass microsphere, a 100-mesh filter, and a 40-60-mesh glass microsphere arranged sequentially from bottom to top inside the sand cup, and the initial pressure of the spinning assembly is 17.9 MPa.

[0017] The filter elements in a sand filter cup are used to filter impurities in the polyester melt. Conventional sand filters are often filled with metal sand, which has high anisotropy, large specific surface area, and stronger filtration capacity. However, the high anisotropy of the metal sand leads to high friction with the melt, resulting in a high temperature rise. Furthermore, it easily punctures the melt, causing zinc oxide whiskers with large aspect ratios to separate from the melt and form agglomerates, ultimately leading to fiber breakage. This application uses glass microspheres as the filter media, which can effectively filter and effectively prevent fiber breakage caused by the agglomeration of zinc oxide whiskers in the melt.

[0018] In any of the above technical solutions, the diameter of the alumina whiskers is 1 to 2 micrometers and the length is 10 to 30 micrometers.

[0019] In any of the above technical solutions, the oiling process uses an emulsion with an oil concentration of 95.5±0.3wt%, an oil temperature of 40±2℃, and a round nozzle with a diameter of 0.16±0.02mm.

[0020] In any of the above technical solutions, the pre-network air pressure is 0.1 to 0.2 MPa, and the main network air pressure is 0.2 to 0.4 MPa.

[0021] In any of the above technical solutions, the annular air pressure during cooling is 16±2Pa, and the annular air temperature is 20.5±1℃.

[0022] The large surface area of ​​FDY fibers, resembling silk, leads to significant friction with the guide yarn during drawing, easily causing a decrease in strength and the formation of white monomer slagging on the guide yarn, affecting the uniformity of fiber dyeing and reducing its dyeing ability. This application addresses this by using the air pressure of a pre-network to homogenize the oil after oiling, eliminating static electricity, increasing the smoothness of the fiber bundle, and allowing the oil to penetrate into the fiber bundle, resulting in tighter cohesion between monofilaments. The gaps between monofilaments are filled with the oil, and during the heating process on the hot rollers, the oil's good thermal conductivity ensures uniform heating of the monofilaments, resulting in more uniform drawing and thus improving dyeing uniformity.

[0023] In addition, oil temperature affects the apparent viscosity of the oil agent. If the temperature is too low, the fluidity is poor and the permeability decreases. If the temperature is too high, the adhesion of the oil agent to the fiber bundle decreases. Unstable oil agent temperature will lead to uneven oiling of the fiber bundle. Through experiments, it was found that when the oil agent temperature is controlled at 40±2℃, the oil agent has the best fluidity, which makes the oiling of the fiber more uniform and the dyeing better. Using this temperature can achieve good permeability and adhesion.

[0024] Secondly, this application provides a silk-like FDY fiber, which is obtained by any of the methods described above; the fiber has a downgrading rate of ≤2.7%, a dyeing degree of ≥4, a breaking strength of ≥4.4cN / dtex, a breaking elongation of 28±3%, a boiling water shrinkage rate of 6.5±0.5%, a dyeing rate of ≥90%, and a K / S value of ≥23.

[0025] In summary, this application has the following beneficial effects: By reducing the temperature of the hot rollers and the draw ratio, the problems of poor dyeing performance and low dye uptake of silk-like FDY fibers are effectively solved. Furthermore, the use of modified zinc oxide whiskers blended with the polyester matrix effectively compensates for the loss of fiber strength caused by insufficient draw, while simultaneously promoting the increase of dye penetration channels within the fiber, further improving the fiber's dyeability. In addition, this application optimizes the filtration structure of the sand cups in the spinning assembly for the application of zinc oxide whiskers, reducing filament breakage. Detailed Implementation

[0026] Preparation Example

[0027] Preparation Example 1: A modified zinc oxide whisker was prepared by the following method: 100g of zinc oxide whiskers (15 μm in length, 1 μm in diameter) were mixed with 5g of aminopropyltrimethoxysilane in ethanol and stirred for 20 min. The whiskers were separated by filtration, and unreacted aminopropyltrimethoxysilane was washed with ethanol. The mixture was then dried in an oven at 50°C to obtain aminated whiskers. 100g of aminated whiskers were added to N,N-dimethylformamide along with 7g of carboxyl-terminated hyperbranched polyester (molecular weight 2800, 12 carboxyl groups). The mixture was reacted at 110°C for 4 h. The whiskers were separated by filtration, washed sequentially with N,N-dimethylformamide and water, and then dried in an oven to obtain the final product.

[0028] Preparation Example 2: A modified zinc oxide whisker was prepared by the following method: 100g of zinc oxide whiskers (10 μm in length and 1 μm in diameter) were mixed with 3.3g of aminopropyltrimethoxysilane in ethanol and stirred for 20 min. The whiskers were separated by filtration, and unreacted aminopropyltrimethoxysilane was washed with ethanol. The mixture was then dried in an oven at 50°C to obtain aminated whiskers. 100g of aminated whiskers were added to N,N-dimethylformamide along with 5g of carboxyl-terminated hyperbranched polyester (molecular weight 5700, carboxyl group number 24). The mixture was reacted at 110°C for 4 h. The whiskers were separated by filtration, washed sequentially with N,N-dimethylformamide and water, and then dried in an oven to obtain the final product.

[0029] Preparation Example 3: A modified zinc oxide whisker was prepared by the following method: 100g of zinc oxide whiskers (20 μm in length, 1 μm in diameter) were mixed with 6g of aminopropyltriethoxysilane in ethanol and stirred for 20 min. The whiskers were separated by filtration, and unreacted aminopropyltriethoxysilane was washed with ethanol. The mixture was then dried in an oven at 50°C to obtain aminated whiskers. 100g of aminated whiskers were added to N,N-dimethylformamide along with 10g of carboxyl-terminated hyperbranched polyester (molecular weight 2600, 12 carboxyl groups). The mixture was reacted at 110°C for 4 h. The whiskers were separated by filtration, washed sequentially with N,N-dimethylformamide and water, and then dried in an oven to obtain the final product.

[0030] Preparation Example 4, a modified zinc oxide, differs from Preparation Example 1 in that an equal amount of zinc oxide whiskers (length 30 micrometers, diameter 1 micrometer) are used to replace zinc oxide whiskers (length 20 micrometers, diameter 1 micrometer).

[0031] Preparation Example 5: A modified zinc oxide whisker was prepared by the following method: Take 100g of zinc oxide whiskers (15 micrometers in length and 1 micrometer in diameter) and mix them with 5g of aminopropyltrimethoxysilane in ethanol. Stir and react for 20 minutes. Filter to separate the whiskers. Wash the unreacted aminopropyltrimethoxysilane with ethanol. Then put it in an oven and dry at 50°C to obtain the final product.

[0032] Preparation Example 6, a modified zinc oxide, differs from Preparation Example 1 in that an equal amount of zinc oxide powder with an average particle size of 200 nm is used to replace zinc oxide whiskers (20 μm in length and 1 μm in diameter).

[0033] Preparation Example 7, a modified calcium carbonate whisker, differs from Preparation Example 1 in that an equal amount of calcium carbonate whiskers (20 micrometers in length and 1 micrometer in diameter) are used to replace zinc oxide whiskers (20 micrometers in length and 1 micrometer in diameter). Example

[0034] Raw material selection in the example: polyester chips with intrinsic viscosity of 0.632±0.006 dL / g and terminal carboxyl group value of 46±3 mol / t.

[0035] Example 1: A silk-like fiber, prepared by the following method: Using an online addition system, 1.5 kg of modified zinc oxide whiskers are added to 98.5 kg of polyester melt. The polyester melt is then filtered through a sand cup in the spinning assembly and extruded from the spinneret to obtain monofilaments with a fineness of 0.56 dtex. The monofilaments are then cooled by ring blowing, oiled and bundled, pre-networked, hot-rolled and shaped, main networked, and wound to obtain 40 dtex / 72F silk-like FDY fiber.

[0036] The sand cup is filled from bottom to top with a 400-mesh filter, 60g of 80-100 mesh glass microspheres, a 100-mesh filter, and 40g of 40-60 mesh glass microspheres. The initial pressure of the spinning assembly is 17.9MPa.

[0037] The ring-blowing air pressure is 16±2 Pa, and the ring-blowing air temperature is 20.5±1℃. The oiling agent is a 95.5wt% emulsion at a temperature of 40℃. The nozzle used is an OJ160 with a round orifice and a diameter of 0.16±0.02 mm. The pre-network air pressure is 0.12 MPa, and the main network air pressure is 0.26 MPa.

[0038] The hot roller drafting and setting process employs a five-roller drafting and setting device, consisting of five hot rollers arranged sequentially: HR1, HR2, HR3, HR4, and HR5. The temperatures of hot rollers HR1, HR2, and HR3 are 82℃, while the temperatures of hot rollers HR4 and HR5 are 132℃. The rotational speeds of HR1, HR2, HR3, HR4, and HR5 are 3080 m / min, 3130 m / min, 3630 m / min, 4650 m / min, and 4650 m / min, respectively. The contact length between the fiber and the hot rollers is 63-64% of the corresponding hot roller outer diameter. The drafting ratio between HR1 and HR2 is 1.04, between HR2 and HR3 is 1.10, and between HR3 and HR4 is 1.28.

[0039] Example 2, a silk-like fiber, prepared by the following method: 2.6 kg of modified zinc oxide whiskers were added to 97.4 kg of polyester melt using an online addition system. The polyester melt was then filtered through a sand cup in the spinning assembly and extruded from the spinneret to obtain monofilaments with a fineness of 0.56 dtex. The monofilaments were then cooled by ring blowing, oiled and bundled, pre-networked, hot-rolled and shaped, main networked, and wound to obtain 40 dtex / 72F silk-like FDY fiber.

[0040] The sand cup is filled from bottom to top with a 400-mesh filter, 60g of 80-100 mesh glass microspheres, a 100-mesh filter, and 40g of 40-60 mesh glass microspheres. The initial pressure of the spinning assembly is 17.9MPa.

[0041] The ring-blowing air pressure is 16±2 Pa, and the ring-blowing air temperature is 20.5±1℃. The oiling agent is a 95.5wt% emulsion at a temperature of 42℃. The nozzle used is an OJ160 with a round orifice and a diameter of 0.16±0.02 mm. The pre-network air pressure is 0.15 MPa, and the main network air pressure is 0.35 MPa.

[0042] The hot roller drafting and setting process employs a five-roll drafting and setting device, consisting of five hot rollers arranged sequentially: HR1, HR2, HR3, HR4, and HR5. The temperatures of hot rollers HR1, HR2, and HR3 are 82℃, while the temperatures of hot rollers HR4 and HR5 are 132℃. The rotational speeds of HR1, HR2, HR3, HR4, and HR5 are 3070 m / min, 3130 m / min, 3620 m / min, 4665 m / min, and 4665 m / min, respectively. The contact length between the fiber and the hot rollers is 63–64% of the outer diameter of the hot rollers. The drafting ratio between HR1 and HR2 is 1.05, between HR2 and HR3 is 1.09, and between HR3 and HR4 is 1.31.

[0043] Example 3, a silk-like fiber, differs from Example 1 in that an equal amount of modified zinc oxide whiskers prepared in Example 3 is used instead of the modified zinc oxide whiskers prepared in Example 1.

[0044] Example 4, a silk-like fiber, differs from Example 1 in that an equal amount of modified zinc oxide whiskers from Example 4 is used instead of the modified zinc oxide whiskers from Example 1.

[0045] Example 5, a silk-like fiber, differs from Example 1 in that an equal amount of modified zinc oxide whiskers prepared in Example 5 is used instead of the modified zinc oxide whiskers prepared in Example 1.

[0046] Example 6, a silk-like fiber, differs from Example 1 in that the glass microspheres in the sand cup are replaced with an equal amount of metal sand. Comparative Example

[0047] Comparative Example 1, a silk-like fiber, differs from Example 6 in that an equal amount of modified zinc oxide from Example 6 is used instead of the modified zinc oxide whiskers from Example 1.

[0048] Comparative Example 2, a silk-like fiber, differs from Example 6 in that an equal amount of modified calcium carbonate whiskers from Preparation Example 7 is used instead of modified zinc oxide whiskers from Preparation Example 1.

[0049] Comparative Example 3, a silk-like fiber, differs from Example 6 in that modified zinc oxide whiskers were not added to the polyester melt.

[0050] Comparative Example 4, a silk-like fiber, differs from Comparative Example 3 in that the draw ratio between HR1 and HR2 is 1.12, the draw ratio between HR2 and HR3 is 1.25, and the draw ratio between HR3 and HR4 is 1.43.

[0051] Performance testing

[0052] 1. Referring to GB / T 6508-2015 "Test Method for Dyeing Uniformity of Polyester Filament", the imitation silk FDY fibers obtained in the examples and comparative examples were woven into socks and dyed. The dyeing rate of the socks was measured by spectrophotometer and the K / S value of the socks was determined by colorimeter.

[0053] 2. Refer to FZ / T 54039-2018 "Irregularly Shaped Polyester Draw Yarn" to determine the fiber dyeing uniformity, breaking strength, breaking elongation, and boiling water shrinkage.

[0054] 3. Downgrading rate of filaments: Filaments are downgraded if there are more than 2 broken filaments on the surface of each filament roll. Each filament roll weighs 8kg. The downgrading rate of filaments = number of downgraded filaments × 100% / total number of filaments.

[0055] 4. Excellent rate = {Total number of pieces - (Number of broken small curls + Number of downgraded pieces with wool + Number of downgraded pieces with dyed fabrics + Number of other downgraded pieces)} × 100% / Total number of pieces.

[0056] Table 1. Performance Test Results

[0057] As shown in Example 1, Comparative Example 3, and Table 1, the addition of modified zinc oxide whiskers during the preparation of FDY fibers significantly improved the dyeing performance, including dyeing rate and K / S value, as well as strength properties such as breaking strength. Furthermore, FDY fibers prepared using non-whiskered zinc oxide powder (Comparative Example 1) exhibited poorer dyeing performance in terms of dyeing rate and K / S value compared to FDY fibers prepared using modified zinc oxide whiskers. This may be because zinc oxide whiskers promote the formation of dye penetration channels within the polyester, while zinc oxide powder is more effective in promoting the formation of crystalline regions, increasing fiber strength but reducing dye penetration channels, which is detrimental to improving dyeing performance. FDY fibers prepared using calcium carbonate whiskers (Comparative Example 2) are prone to forming fuzz during manufacturing, reducing the product yield. This may be because calcium carbonate, compared to zinc oxide, is less effective in improving the antistatic properties of the fiber. For silk-like FDY fibers with a small fineness and large specific surface area, static electricity is easily generated during the spinning process, leading to fuzz formation.

[0058] As shown in Example 4 and Table 1, if the aspect ratio of the zinc oxide whiskers is too long, the resulting fiber fuzzing and breakage will increase, and the product yield will decrease. As shown in Example 5 and Table 1, modifying zinc oxide whiskers with only an aminosilane coupling agent results in fibers with poor strength properties. As shown in Example 6 and Table 1, compared to glass microsphere filtration, metal sand filtration makes the resulting FDY fibers more prone to fuzzing and breakage, leading to a decrease in the product yield.

[0059] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A process for the production of a silk-like FDY fiber, characterized by, Modified zinc oxide whiskers (1-3% by weight) are added to the polyester melt via an online addition system. The melt is then extruded from the spinning assembly to obtain monofilaments with a fineness of 0.5-1 dtex. These monofilaments are then sequentially cooled, oiled, pre-networked, hot-rolled drawn and shaped, main-networked, and wound to produce silk-like FDY fibers. The aspect ratio of the zinc oxide whiskers is 10-20. The hot-rolled drawn and shaped process uses five sets of hot rollers: HR1, HR2, HR3, HR4, and HR5. The temperatures of HR1, HR2, and HR3 are 82±2℃, and the temperatures of HR4 and HR5 are 132±2℃. The draw ratio between HR1 and HR2 is 1.01-1.06, between HR2 and HR3 is 1.08-1.12, and between HR3 and HR4 is 1.20-1. .32; The modified zinc oxide whiskers are prepared by mixing zinc oxide whiskers with an aminosilane coupling agent in ethanol at a mass ratio of 100:3 to 6, filtering, washing, and drying to obtain aminated whiskers; then adding the aminated whiskers and carboxyl-terminated hyperbranched polyester in N,N-dimethylformamide at a mass ratio of 100:5 to 10, reacting at 100 to 120°C, filtering, washing, and drying to obtain the modified zinc oxide whiskers; the diameter of the modified zinc oxide whiskers is 1 to 2 micrometers and the length is 10 to 30 micrometers.

2. The production method according to claim 1, characterized by, The rotational speeds of HR1, HR2, and HR3 are 3080±20m / min, 3130±20m / min, and 3630±20m / min, respectively, and the rotational speeds of HR4 and HR5 are 4650±20m / min; and / or the contact length between the fiber and the hot roller is 62 to 66% of the outer diameter of the hot roller.

3. The preparation method according to claim 1, characterized in that, The molecular weight of the end-carboxyl hyperbranched polyester is 1000-6000, and the carboxyl content per unit molar mass of the end-carboxyl hyperbranched polyester is 6-24 moles.

4. The preparation method according to claim 1, characterized in that, The spinning assembly has a 400-mesh filter, an 80-100-mesh glass microsphere, a 100-mesh filter, and a 40-60-mesh glass microsphere arranged sequentially from bottom to top inside the sand cup. The initial pressure of the spinning assembly is 17.9 MPa.

5. The preparation method according to claim 1, characterized in that, The oiling process uses an emulsion with an oil concentration of 95.5±0.3wt%, an oil temperature of 40±2℃, and a round nozzle with a diameter of 0.16±0.02mm.

6. The preparation method according to claim 1, characterized in that, The pre-network pressure is 0.1–0.2 MPa, and the main network pressure is 0.2–0.4 MPa.

7. The preparation method according to claim 1, characterized in that, The cooling ring air pressure is 16±2Pa and the ring air temperature is 20.5±1℃.

8. A silk-like FDY fiber, characterized in that, The fiber is prepared by any one of the preparation methods described in claims 1 to 7; the fiber has a downgrading rate of ≤2.7%, a dyeing uniformity of ≥4, a breaking strength of ≥4.4cN / dtex, a breaking elongation of 28±3%, a boiling water shrinkage rate of 6.5±0.5%, a dyeing rate of ≥90%, and a K / S value of ≥23.

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