Preparation method of high-thermal-conductivity cool-feeling fabric

Abstract

The invention provides a preparation method of a high-thermal-conductivity cool-feeling fabric, which comprises the following steps: S10: mixing alpha-alumina and boehmite according to a mass ratio of 85: 15-95: 5, the alpha-alumina and boehmite are spherical or sphere-like and have a median particle size D50 of 0.1-0.9 [mu] m, and adding a silane coupling agent accounting for 0.8-1.2% of the total mass of the powder for surface coating treatment to obtain modified powder; s20, the modified powder and polyester chips are mixed, the mass percent of the modified powder ranges from 10% to 30%, the mixture is subjected to melt extrusion granulation through a double-screw extruder, and cool master batches are obtained; s30, respectively feeding the cool master batch and the common polyester chip according to the proportion that the cool master batch accounts for 2-5% of the total weight, uniformly mixing in a molten state, extruding by a spinneret plate, cooling, winding and post-processing to obtain the cool polyester staple fiber; s40, carding, drawing and spinning the cool polyester staple fibers into yarns, and weaving the yarns to obtain the high-thermal-conductivity cool fabric. The high-thermal-conductivity cool fabric prepared by the preparation method has the advantages of good durability and good washing resistance.

Description

Technical Field

[0001] This invention relates to the field of cooling fabric technology, specifically to a method for preparing a high thermal conductivity cooling fabric. Background Technology

[0002] Polyethylene terephthalate (PET, commonly known as polyester) fiber is widely used in the clothing industry due to its high strength, good elasticity, and durability. However, ordinary polyester fiber has a low thermal conductivity and poor breathability and moisture absorption, which can easily cause a stuffy feeling when worn in high-temperature environments. Currently, the main way to achieve the cooling function of polyester fabric is through finishing with additives, which typically involves attaching additives such as xylitol and silicone oil to the fabric surface. Although this method can improve the hydrophilicity or smoothness of the fabric, thereby producing a cooling sensation, this cooling effect is usually not lasting, has poor washability, and its function will significantly diminish after repeated washing. Summary of the Invention

[0003] The purpose of this invention is to overcome the above-mentioned defects or problems in the prior art and provide a method for preparing a high thermal conductivity cooling fabric. The high thermal conductivity cooling fabric prepared by this method has the advantages of good durability and good washability.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: Technical Solution 1: A method for preparing a high thermal conductivity cooling fabric, comprising the following steps: S10: Mixing α-alumina and boehmite at a mass ratio of 85:15 to 95:5, wherein the α-alumina and boehmite are spherical or near-spherical with a median particle size D50 of 0.1 μm to 0.9 μm, and adding 0.8% to 1.2% of a silane coupling agent by mass of the powder for surface coating treatment to obtain modified powder; S20: Mixing the modified powder with polyester chips, wherein the mass percentage of the modified powder is 10% to 30%, and granulating by melt extrusion using a twin-screw extruder to obtain cooling masterbatch; S30: Feeding the cooling masterbatch and ordinary polyester chips separately at a ratio of 2% to 5% of the cooling masterbatch by mass, mixing uniformly in a molten state, and extruding, cooling, winding, and post-treatment to obtain cooling polyester staple fiber; S40: The cooling polyester staple fiber is combed, drawn, and worsted into yarn, and then the yarn is woven into a high thermal conductivity cooling fabric.

[0005] Technical Solution 2 based on Technical Solution 1: In step S10, before the coating treatment, the mixed α-alumina and boehmite are heated to 110°C for drying; the coating treatment is carried out by stirring at a speed of 1000 r / min for 10 to 20 minutes.

[0006] Technical Solution 3 based on Technical Solution 1: In step S20, before melt extrusion granulation, the polyester chips are dried by forced air at 170°C to 180°C, and the modified powder is dried by vacuum at 70°C to 80°C.

[0007] Technical Solution 4 based on Technical Solution 1: In step S20, the homogenization section temperature of the twin-screw extruder is set to 275°C to 280°C, and the screw speed is set to 300 r / min to 500 r / min.

[0008] Technical Solution 5 based on Technical Solution 1: The intrinsic viscosity of the cooling masterbatch obtained in step S20 is 0.55 dL / g to 0.60 dL / g; the intrinsic viscosity of the ordinary polyester chips in step S30 is 0.640 ± 0.005 dL / g.

[0009] Technical Solution Six based on Technical Solution One: In step S30, the temperature of the melt spinning chamber is 285°C to 295°C, the spinneret orifice diameter is 0.20mm to 0.25mm, and the length-to-diameter ratio is 2:1 to 3:1.

[0010] Technical solution seven based on technical solution one: In step S30, the post-processing includes two water bath stretching processes on the wound fiber, with a total stretching ratio of 3.5 to 4.0 times; then heat setting is performed at a temperature of 145°C to 155°C; finally, the fiber is cut into short fibers with a length of 38 mm or 51 mm.

[0011] Technical solution eight based on technical solution one: In step S40, 8 slivers are combined in the carding and drawing process; in the worsted spinning process, the total draft ratio of the fine yarn is 6 times, and the fine yarn spindle speed is 12000r / min to 18000r / min.

[0012] Technical Solution Nine based on Technical Solution One: In step S40, the knitting process adopts a plain weave fabric, and the resulting fabric has a weight of 145g / m² to 155g / m².

[0013] Technical solution ten based on technical solution one: the sphericity of the α-alumina and boehmite in step S10 is greater than 0.9, and the maximum particle size D98 of the modified powder is less than 2.0 μm. As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following beneficial effects: Technical Solution 1 provides a method for preparing a high thermal conductivity cooling fabric. This method involves directly adding thermally conductive mineral powder to a polyester matrix during the spinning process, and then using this modified polyester matrix to spin-dry cooling polyester staple fibers before preparing the high thermal conductivity cooling fabric. This improves upon the problems of poor durability and poor washability found in existing auxiliary finishing methods. Specifically, this solution adds α-alumina, a material with high thermal conductivity, during the modification of the polyester matrix. While this material provides better thermal conductivity, α-alumina has high hardness. During melt spinning, when the hard particles flow through the micro-orifices of the spinneret, they exert a continuous cutting effect on the metal orifice walls. This wear can cause the spinneret orifice diameter to expand or deform in a short time, resulting in uneven fiber fineness and, in severe cases, forcing frequent production line shutdowns for component replacement. Therefore, this solution specifically incorporates a specific proportion of boehmite into the α-alumina. Boehmite has a layered crystal structure and low hardness. During melt flow, the lower-hardness boehmite particles in the mixture can distribute between the high-hardness α-alumina particles and the metal flow channel wall, acting as a buffer and isolation similar to a solid lubricant. This compounding method retains α-alumina as the main heat-conducting framework while utilizing boehmite to reduce the overall mechanical wear of the equipment caused by the powder. Furthermore, addressing the issue of agglomeration and clogging at micro-spinnerets when the inorganic powder filling amount increases, this solution limits the powder to submicron-sized spherical or near-spherical shapes and incorporates a silane coupling agent for surface chemical coating. Compared to the flake-like or angular particles formed by conventional mechanical crushing, the friction between spherical particles and between particles and the tube wall during shear flow is primarily rolling friction. Combined with the organic molecular layer on the surface, this reduces the flow resistance of the powder-containing melt, thus avoiding bridging by irregular particles in narrow orifices and ensuring smooth melt passage through the spinneret. Furthermore, this method combines masterbatch preparation with online addition. First, the high-concentration powder is pre-dispersed in the carrier through the strong shearing action of twin-screw extrusion, and then diluted online into the main polyester at a lower ratio. This preparation method avoids most of the main polyester chips undergoing secondary high-temperature strong shearing, preserving the molecular weight and intrinsic viscosity of the polyester matrix. This ensures that the final fiber, even after being filled with inorganic powder, still possesses the mechanical strength required for spinning and weaving, overcoming the defect that high filler content usually leads to a significant decrease in fiber strength.

[0014] In technical solution two, the mixed powder is dried at high temperature before coating modification, and the process parameters for high-speed stirring modification are limited. This pre-drying treatment removes physically adsorbed water from the surface of the inorganic powder, preventing pre-hydrolysis of the silane coupling agent before contact with the powder and ensuring effective chemical bonding between the coupling agent and the hydroxyl groups on the powder surface. Combined with the shear dispersion effect generated by high-speed stirring, the atomized coupling agent can be uniformly spread on the surface of each spherical powder to form a monolayer or low-molecular-weight layer coating, avoiding excessive local coating or leakage, thereby improving the compatibility and dispersion stability of the inorganic powder in the organic matrix.

[0015] In technical solution three, the polyester chips and modified powder are dried under specific conditions. High-temperature forced-air drying of the polyester chips reduces the moisture content of the resin, preventing hydrolytic degradation of the polyester molecular chains during high-temperature melting and maintaining the viscosity of the matrix. Vacuum drying of the modified powder utilizes a negative pressure environment to effectively extract air and residual small molecules trapped within the pores and agglomerates of the fine powder, preventing bubbles and voids caused by gas expansion or volatilization during masterbatch preparation, thus ensuring a dense structure in the resulting masterbatch.

[0016] In technical solution four, the homogenization section temperature and screw speed of the twin-screw extruder are limited. This specific temperature range ensures the polyester matrix has suitable fluidity to wet the powder, while avoiding thermal degradation of the matrix due to excessively high temperatures. The higher screw speed provides strong mechanical shear force, effectively breaking down soft agglomerates between submicron-sized inorganic powders, dispersing them into independent particles that are uniformly distributed within the polyester matrix. This ensures the microscopic dispersion uniformity of the powder in the high-filler masterbatch, avoiding pressure fluctuations or breakage in subsequent spinning components caused by the presence of agglomerates.

[0017] In technical solution five, the uniformity of online mixing is promoted by controlling the difference in intrinsic viscosity between the cooling masterbatch and ordinary polyester chips. By controlling the intrinsic viscosity of the masterbatch to be slightly lower than that of ordinary polyester chips, the lower viscosity masterbatch melt has a stronger tendency to flow and diffuse compared to the higher viscosity bulk melt during the melt mixing stage. This drives the masterbatch to quickly penetrate and expand to the interface of the bulk melt. During the short residence time in the static mixer, the high concentration of powder in the masterbatch can also be quickly and uniformly diluted and dispersed into the bulk polyester, avoiding fiber evenness or color difference caused by uneven mixing.

[0018] Technical Solution Six specifies the temperature of the spinning box and the relevant process parameters of the spinneret. A higher box temperature ensures sufficient fluidity of the filled melt as it passes through the micropores, reducing shear viscosity. Combined with the selected spinneret orifice diameter and aspect ratio, a stable melt flow state is achieved. This provides sufficient back pressure to eliminate the instability of melt fracture while avoiding excessive shear stress that could cause turbulence or orifice buildup. These process parameter limitations significantly reduce filament drift and breakage rates during spinning, ensuring production continuity.

[0019] In technical solution seven, two water bath drawing processes fully stretch the nascent fibers, causing the polymer chains to be highly oriented and crystallized along the fiber axis, effectively compensating for the fiber strength loss caused by the addition of inorganic fillers. Heat setting eliminates residual stress within the fiber, fixes the fiber structure, and ensures the dimensional stability of the fiber during subsequent processing and use. Cutting the fiber to a specific length facilitates conventional blending processes.

[0020] In technical solution eight, the number of slivers, the yarn draft ratio, and the spindle speed during the spinning process are set to ensure the evenness of the yarn, reduce weight deviation, and enable the weaving of fine yarns with a tight structure and evenness.

[0021] In technical solution nine, the plain weave fabric gives it a smooth and even surface, maximizing the effective contact area between the skin and the fabric, which facilitates rapid heat conduction through the highly thermally conductive fibers. The limited fabric weight ensures that it is lightweight and breathable while containing sufficient thermally conductive powder per unit area, thus fully utilizing the material's instantaneous cooling properties without sacrificing summer wearing comfort.

[0022] In technical solution ten, the sphericity is limited to greater than 0.9, which can ensure that the frictional resistance is reduced to a suitable value. At the same time, the maximum particle size D98 is controlled to be less than 2.0μm to avoid the mixing of large particles and ensure that no particles larger than or close to the spinneret orifice diameter enter the component. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are preferred embodiments of the present invention and should not be considered as excluding other embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] In the claims and description of this invention, the terms "comprising," "having," and variations thereof are used to mean "including but not limited to."

[0025] This invention relates to a method for preparing a high thermal conductivity cooling fabric, which mainly includes the following steps: S10: α-alumina and boehmite are mixed at a mass ratio of 85:15 to 95:5, wherein the α-alumina and boehmite are spherical or near-spherical and the median particle size D50 is 0.1 μm to 0.9 μm, and 0.8% to 1.2% of silane coupling agent is added for surface coating treatment to obtain modified powder; S20: The modified powder is mixed with polyester chips, wherein the mass percentage of the modified powder is 10% to 30%, and then melt-extruded and granulated by a twin-screw extruder to obtain a cooling masterbatch. S30: The cooling masterbatch and ordinary polyester chips are fed into the mixture at a ratio of 2% to 5% of the total weight of the cooling masterbatch, and mixed evenly in a molten state. The mixture is then extruded through a spinneret, cooled, wound, and post-treated to obtain cooling polyester staple fiber. S40: The cooling polyester staple fiber is combed, drawn and spun into yarn, and then the yarn is woven to obtain a high thermal conductivity cooling fabric.

[0026] The following will provide a detailed explanation of each of the above steps.

[0027] First, step S10 will be described in detail. The purpose of step S10 is to provide a polyester compound system that combines high thermal conductivity, low abrasion and excellent dispersibility, thereby improving the application challenges of high-hardness inorganic powders in chemical fiber spinning.

[0028] First, the raw materials are selected and compounded. Alpha-alumina is selected as the main filler to provide high thermal conductivity, and boehmite is selected as the auxiliary filler to provide lubrication and buffering. During the selection process, the microstructure and particle size of the two powders must be controlled. Both the selected alpha-alumina and boehmite powders should be spherical or near-spherical, with a sphericity preferably greater than 0.9. This utilizes their geometric symmetry to convert the sliding friction of the particles during melt flow and contact with the equipment wall into rolling friction, reducing wear and rheological resistance. Regarding particle size, the median particle size D50 of both powders is limited to between 0.1 μm and 0.9 μm, preferably between 0.3 μm and 0.5 μm. Furthermore, the powders must be free of coarse particles, ensuring that the maximum particle size D98 is less than 2.0 μm to prevent pore blockage during subsequent spinning. Two powders were weighed according to a mass ratio of α-alumina to boehmite of 85:15 to 95:5 and placed in a high-speed mixer for physical premixing to ensure that the boehmite particles were evenly dispersed among the α-alumina particles.

[0029] Next, a pre-treatment of powder drying is performed. To eliminate adsorbed physical water on the surface of the inorganic powder and prevent it from interfering with the subsequent chemical reaction of the silane coupling agent, the uniformly mixed powder needs to be dried under heating conditions. Specifically, the mixed powder is placed in a heating device, heated to 110℃, and maintained at a constant temperature for drying. During the drying process, low-speed stirring can be turned on to ensure uniform heating of the powder until the powder moisture content drops to a low level, for example, below 0.1%.

[0030] Finally, surface chemical coating treatment is performed. A silane coupling agent, such as KH-550 (γ-aminopropyltriethoxysilane), is selected as the surface modifier, and its dosage is controlled between 0.8% and 1.2% of the total powder mass. This dosage range is based on the theoretical value required for monolayer or low-molecular-weight layer coating calculated from the specific surface area of ​​the powder, ensuring complete coating while avoiding slippage or small molecule residue caused by excessive coupling agent. The modification operation is carried out in a high-speed mixer. The dried hot powder is kept at a suitable reaction temperature, and the silane coupling agent is diluted into a solution (such as an ethanol solution) and then uniformly sprayed into the mixer in a mist form. At the same time, the stirring speed of the mixer is set to a high speed of 1000 r / min, and the reaction is continuously stirred at this speed for 10 to 20 minutes. The strong shear force field generated by the high speed helps to break up the soft agglomeration of the powder, allowing the atomized coupling agent to spread rapidly and uniformly on the surface of each spherical particle and undergo a condensation reaction with the hydroxyl groups on the powder surface to form a strong chemical bond layer. After the reaction is complete, the solvent vapor needs to be removed and the mixture dried to obtain a modified powder with organic active groups on the surface, good flowability, and excellent compatibility in the polyester matrix.

[0031] Next, step S20 will be described in detail. Step S20 mainly involves dispersing the modified powder obtained in step S10 into a polyester matrix to prepare a cooling masterbatch.

[0032] Before melt extrusion, the raw materials need to be dried to prevent moisture from affecting the processing and product quality. Specifically, polyester chips are placed in a forced-air drying device and dried at 170°C to 180°C to remove moisture from the inside and surface of the chips, preventing hydrolysis of the polyester during high-temperature melting. Simultaneously, the modified powder obtained in step S10 is placed in a vacuum drying device and dried at 70°C to 80°C. This negative pressure environment removes air and small volatile molecules from the gaps and micropores between powder particles, ensuring the powder is in a compact and dry state.

[0033] After drying, the ingredients are mixed. The dried modified powder is mixed with the dried polyester chips at a ratio of 10% to 30% by mass. The mixed material is then fed into a twin-screw extruder for melt extrusion granulation. During extrusion, the process parameters of the twin-screw extruder are crucial to the quality of the masterbatch. The temperature of the extruder's homogenization section is set to 275℃ to 280℃. This temperature range ensures that the polyester matrix is ​​fully melted and has good fluidity to wet the powder, while avoiding severe thermal degradation of the polyester due to excessive temperature. Simultaneously, the screw speed is set to 300 rpm to 500 rpm. The strong shear force generated by the high speed breaks up the agglomerated powder particles and disperses them evenly in the polyester melt.

[0034] After being extruded by a twin-screw extruder, the material is cooled in a water bath to form strips, and then cut into pellets by a pelletizer to obtain the cooling masterbatch. By controlling the drying conditions of the above raw materials and the extrusion process parameters, the intrinsic viscosity of the obtained cooling masterbatch is controlled between 0.55 dL / g and 0.60 dL / g. This viscosity range is slightly lower than that of conventional spinning-grade polyester chips, which helps the masterbatch to diffuse rapidly and mix evenly in the bulk melt during subsequent online addition.

[0035] Next, step S30 will be described in detail. Step S30 mainly involves online mixing and spinning of the cooling masterbatch obtained in step S20 with ordinary polyester chips, followed by post-treatment to produce cooling polyester staple fibers.

[0036] First, ordinary polyester chips are prepared as the main raw material, and the intrinsic viscosity of the ordinary polyester chips needs to be controlled within the range of 0.640±0.005 dL / g. An online addition process is adopted, with the cooling masterbatch and ordinary polyester chips fed into the spinning system separately through a metering device. The addition amount of the cooling masterbatch is controlled at 2% to 5% of the total weight. Since the intrinsic viscosity of the cooling masterbatch obtained in step S20 (0.55 dL / g to 0.60 dL / g) is slightly lower than that of the ordinary polyester chips, during the melt mixing process, the lower viscosity masterbatch melt diffuses more easily into the higher viscosity bulk melt, thus ensuring that even at a low addition ratio, the masterbatch can achieve rapid and uniform dispersion in the bulk melt.

[0037] The homogeneously mixed melt then enters the spinning box for extrusion spinning. To ensure that the melt containing inorganic powder can pass smoothly through the micropores without clogging or melt breakage, the temperature of the spinning box is set to 285°C to 295°C. Simultaneously, a spinneret with an orifice diameter of 0.20mm to 0.25mm and an aspect ratio of 2:1 to 3:1 is selected. The melt is extruded through the spinneret to form a fine stream, which is then cooled and solidified by a cooling device before being wound on a winding machine to form nascent fiber bundles.

[0038] Finally, the nascent fiber bundles undergo post-treatment to impart the mechanical properties required for spinning. The post-treatment process mainly includes drafting, heat setting, and cutting. First, the wound fibers undergo two water bath drafting processes, with the total draft ratio controlled between 3.5 and 4.0 times. This stretching action causes the fiber macromolecules to align and crystallize, improving fiber strength. The drafted fibers then enter the heat setting process, with the heat setting temperature controlled between 145℃ and 155℃ to eliminate internal fiber stress and improve dimensional stability. The set fibers are then cut by a cutting machine into cotton-type staple fibers with a length of 38mm or 51mm, yielding the final cool-feeling polyester staple fiber.

[0039] Next, step S40 will be described in detail. Step S40 mainly involves spinning the cool-feeling polyester staple fiber obtained in step S30 into yarn, which is then woven into fabric. In this embodiment, knitting is preferably used.

[0040] The spinning process begins with the cutting of cool-feeling polyester staple fibers into a cotton spinning machine, where they undergo opening, cleaning, and carding processes to produce sliver. To improve yarn evenness and fiber parallelism, eight slivers are combined and drafted during the drawing process. The yarn is then roving-produced before entering the worsting process. In worsting, the total draft ratio of the yarn is set to 6, and the spindle speed of the spinning machine is set to 12,000 to 18,000 rpm. At this relatively high spindle speed and specific draft ratio, the fibers are tightly bound together, resulting in a dense and even yarn structure with the strength required for subsequent high-speed knitting.

[0041] After obtaining the yarn, the knitting process begins. The yarn is fed into knitting equipment for weaving, using a plain weave fabric structure. Plain weave fabric features a smooth surface and clear texture, maximizing the effective contact area between the fabric and the skin, thus facilitating rapid heat transfer through the highly thermally conductive fibers. During the weaving process, the loop length and density are controlled to maintain the fabric weight between 145g / m² and 155g / m². This weight range ensures the fabric is lightweight and breathable, suitable for summer wear, while also ensuring sufficient thermally conductive powder per unit area, resulting in an excellent instant cooling effect upon contact.

[0042] The following specific embodiment illustrates the preparation method.

[0043] α-alumina powder with a sphericity of 0.95, a median particle size D50 of 0.4 μm, and a maximum particle size D98 of 1.8 μm and boehmite powder were selected. The raw materials were weighed at a mass ratio of α-alumina to boehmite of 90:10 and added to a high-speed mixer. The heating device was turned on, and the mixed powder was heated to 110℃ and kept dry for 30 min. Subsequently, silane coupling agent KH-550 was weighed at a ratio of 1.0% of the total powder mass, dissolved in anhydrous ethanol to prepare a solution, and sprayed into the high-speed mixer by atomization. The mixer speed was set to 1000 r / min, and the reaction was carried out at this speed for 15 min. After the reaction was completed, the solvent vapor was discharged, yielding the modified powder.

[0044] Fiber-grade polyester chips with an intrinsic viscosity of 0.64 dL / g were placed in a forced-air drying oven and dried at 180°C for 4 hours to reduce their moisture content to below 30 ppm. Simultaneously, the modified powder obtained in step S10 was placed in a vacuum drying oven and dried at 80°C and -0.09 MPa for 4 hours. The modified powder and polyester chips were mixed at a ratio of 20% by mass and 80% by mass. The mixture was added to a twin-screw extruder, with the homogenization section temperature set to 278°C and the screw speed at 400 r / min. After shearing dispersion, melt extrusion, water-cooling drawing, and pelletizing, a cooling masterbatch was obtained. The intrinsic viscosity of this cooling masterbatch was measured to be 0.58 dL / g.

[0045] Ordinary polyester chips with an intrinsic viscosity of 0.64 dL / g were prepared as the main material. Using an online addition process, the dried ordinary polyester chips and the dried cooling masterbatch obtained in step S20 were fed into the spinning system separately via metering pumps. The addition ratio of the cooling masterbatch was set to 2% of the total weight (i.e., the inorganic powder content in the final fiber was 0.4%). The melt flow was uniformly mixed in a static mixer with an aspect ratio of 12 and then entered the spinning box. The box temperature was set to 290℃, and a spinneret with an aperture of 0.22 mm and an aspect ratio of 2.5:1 was used for extrusion. The extruded fine stream was cooled by side blowing and wound into nascent fibers at a speed of 1200 r / min. The nascent fibers were then post-treated: subjected to two water bath stretching processes with a total stretch ratio of 3.8; crimped by a mechanical crimping machine; heat-set at 150℃ for 10 min; and finally cut into short fibers with a length of 38 mm.

[0046] The obtained cooling polyester staple fiber is fed into a cotton spinning machine. After opening, cleaning, and carding, eight slivers are combined in the drawing process. In the worsted spinning process, the total draft ratio of the yarn is set to 6, and the spindle speed is 16000 r / min to produce 40S yarn. The yarn is then fed into a circular knitting machine and woven using a plain weave structure, with the weave density controlled. After setting, a high thermal conductivity cooling fabric with a weight of 150 g / m² is obtained.

[0047] The cooling polyester staple fiber and fabric prepared in the above embodiments were subjected to performance tests. The test standards and results are shown below:

[0048] The above results show that, in Example 1, with only 0.4% inorganic powder added, the fabric's Q-max value reached 0.20 J / (cm²·s), significantly higher than the national standard (≥0.15 J / (cm²·s)). Furthermore, the cooling sensation remained virtually unchanged after 20 washes, demonstrating the durability of the cooling function. Simultaneously, the fibers maintained high mechanical strength (5.6 cN / dtex), and the spinning assembly achieved a continuous operating cycle of up to 25 days, verifying the technical effectiveness of this invention in addressing equipment wear and spinnability.

[0049] The foregoing description of the specifications and embodiments is intended to explain the scope of protection of this invention, but does not constitute a limitation on the scope of protection of this invention. Modifications, equivalent substitutions, or other improvements to the embodiments of this invention or a portion thereof that can be obtained by those skilled in the art through logical analysis, reasoning, or limited experimentation, based on the teachings of this invention or the foregoing embodiments, in conjunction with common knowledge, general technical knowledge, and / or existing technology, should all be included within the scope of protection of this invention.

Claims

1. A method for preparing a high thermal conductivity cooling fabric, characterized in that, Includes the following steps: S10: α-alumina and boehmite are mixed at a mass ratio of 85:15 to 95:5, wherein the α-alumina and boehmite are spherical or near-spherical and the median particle size D50 is 0.1 μm to 0.9 μm, and 0.8% to 1.2% of silane coupling agent is added for surface coating treatment to obtain modified powder; S20: The modified powder is mixed with polyester chips, wherein the mass percentage of the modified powder is 10% to 30%, and then melt-extruded and granulated by a twin-screw extruder to obtain a cooling masterbatch. S30: The cooling masterbatch and ordinary polyester chips are fed into the mixture at a ratio of 2% to 5% of the total weight of the cooling masterbatch, and mixed evenly in a molten state. The mixture is then extruded through a spinneret, cooled, wound, and post-treated to obtain cooling polyester staple fiber. S40: The cooling polyester staple fiber is combed, drawn and spun into yarn, and then the yarn is woven to obtain a high thermal conductivity cooling fabric.

2. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, In step S10, the mixed α-alumina and boehmite are heated to 110°C and dried before the coating treatment; the coating treatment is carried out by stirring at 1000 r / min for 10 to 20 minutes.

3. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, In step S20, before melt extrusion granulation, the polyester chips are dried by forced air at 170°C to 180°C, and the modified powder is dried by vacuum at 70°C to 80°C.

4. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, In step S20, the homogenization section temperature of the twin-screw extruder is set to 275°C to 280°C, and the screw speed is set to 300 r / min to 500 r / min.

5. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, The intrinsic viscosity of the cooling masterbatch obtained in step S20 is 0.55 dL / g to 0.60 dL / g; the intrinsic viscosity of the ordinary polyester chips in step S30 is 0.640 ± 0.005 dL / g.

6. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, in In step S30, the temperature of the melt spinning chamber is 285°C to 295°C, the spinneret orifice diameter is 0.20mm to 0.25mm, and the length-to-diameter ratio is 2:1 to 3:

1.

7. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, in In step S30, the post-processing includes performing two water bath stretching operations on the wound fibers, with a total stretching ratio of 3.5 to 4.0 times; then performing heat setting at a temperature of 145°C to 155°C; and finally cutting the fibers into short fibers with a length of 38 mm or 51 mm.

8. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, in In step S40, the carding and drawing process uses 8 slivers combined; in the worsted spinning process, the total draft ratio of the yarn is 6 times, and the yarn spindle speed is 12000 r / min to 18000 r / min.

9. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, in In step S40, the knitting process uses a plain weave fabric, and the resulting fabric has a weight of 145g / m² to 155g / m².

10. The method for preparing a high thermal conductivity cooling fabric as described in claim 1, characterized in that, In step S10, the sphericity of the α-alumina and boehmite is greater than 0.9, and the maximum particle size D98 of the modified powder is less than 2.0 μm.

Images