Cool-feeling functional master batch based on modified boron nitride and fiber preparation method of cool-feeling functional master batch

Abstract

The invention belongs to the technical field of high polymer material modification, and particularly discloses a cool-feeling functional master batch based on modified boron nitride and a fiber preparation method of the cool-feeling functional master batch. Hexagonal boron nitride is subjected to hydroxylation pretreatment through NaOH, and the surface activity of the hexagonal boron nitride is activated; then, a silane coupling agent and a titanate coupling agent are compounded, grafted and modified according to the proportion of 3: 1, and the dispersity and interface bonding strength of mBN in the resin are remarkably improved. The double-resin-system master batch is developed aiming at different matrixes: ethylene diamine tetra (methylene phosphonic acid) sodium is added into a PET system to stabilize a molecular chain structure, a PA6 system is grafted with polypropylene wax and POE through maleic anhydride to construct a chemical-physical double-crosslinking network, and toughening and rigidity are balanced. The problems of filler agglomeration, large interface thermal resistance, mechanical property attenuation and the like are effectively solved, and the prepared fiber has efficient heat dissipation, excellent mechanical property and stable processability and can be widely applied to the field of cool-feeling textiles.

Description

Technical Field

[0001] This invention relates to the field of polymer material modification technology, and specifically discloses a cooling functional masterbatch based on modified boron nitride and its fiber preparation method. Background Technology

[0002] The core of cooling functionality lies in the material's ability to quickly dissipate heat from the human body surface, reducing heat accumulation at the contact interface and thus creating an instant cooling experience. However, existing cooling materials still have significant shortcomings in terms of thermal conductivity, mechanical properties, and processing stability, which restricts their industrial application.

[0003] Traditional cooling materials often rely on the moisture-wicking properties of natural fibers (such as cotton and linen) or passive heat dissipation through the addition of metal particles or phase change materials (PCMs). However, natural fibers generally have low thermal conductivity (cotton approximately 0.04 W / (m·K)), making it difficult to meet the demands of efficient heat dissipation. While metal particles can improve thermal conductivity, they can increase material rigidity, degrade the feel, and pose an oxidation risk. Phase change materials, due to their limited enthalpy, cannot sustain their effectiveness at high temperatures. In recent years, polymer composites filled with thermally conductive fillers (such as boron nitride and graphene) have become a research hotspot, significantly improving the material's heat transfer efficiency by constructing a three-dimensional thermally conductive network. However, these materials still face the following key challenges in practical applications: inorganic fillers such as boron nitride (BN) tend to agglomerate in the polymer matrix due to their surface inertness, leading to discontinuous thermally conductive networks. While high filler content can improve thermal conductivity, it often sacrifices the material's mechanical properties. During melt spinning, existing cooling fibers are prone to interfacial stress concentration due to the large difference in thermal expansion coefficients between the filler and the matrix, leading to fiber breakage or damage to the thermal conductivity network. Furthermore, traditional spinning processes lack precise control over the cooling process, making it difficult to optimize fiber crystallinity and orientation, further limiting the cooling performance. Most cooling materials only focus on instantaneous heat conduction, neglecting thermal stability during long-term use. For example, phase change materials are prone to leakage during repeated phase changes, while metal fillers may oxidize and fail at high temperatures. In addition, existing materials exhibit poor dimensional stability in humid and hot environments, easily leading to a decline in cooling performance.

[0004] To address the aforementioned issues, this invention proposes a cooling functional masterbatch based on modified boron nitride (mBN) and its fiber preparation method, achieving synergistic optimization of thermal conductivity, mechanical properties, and contact cooling sensation through multi-dimensional innovative design. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art by providing a cooling functional masterbatch based on modified boron nitride and its fiber preparation method, so as to solve the problems mentioned in the above-mentioned technical background.

[0006] To achieve the above objectives, the present invention provides the following technical solution: On one hand, the present invention provides a cooling functional masterbatch based on modified boron nitride, a premix composed of 80-120 parts by weight of PET masterbatch and 380-420 parts by weight of PA6 composite masterbatch, which is used for subsequent melt spinning. The PET masterbatch comprises: modified boron nitride mBN, PET chips, and sodium ethylenediaminetetramethylenephosphonate (EDTMPS); wherein, the modified boron nitride mBN is prepared by: boron nitride hydroxylation pretreatment and graft modification with compound modifiers; The preparation of PA6 composite masterbatch includes: grafting maleic anhydride onto polypropylene wax and preparing PA6 resin system.

[0007] Preferably, the compound modifier is a mixture of silane coupling agent and titanate coupling agent in a 3:1 ratio.

[0008] On the other hand, the present invention provides a cooling functional masterbatch based on modified boron nitride and a method for preparing its fibers, the specific preparation steps of which are as follows: S1: Boron nitride hydroxylation pretreatment: 15-25 g of hexagonal boron nitride (h-BN) nanosheets with a thickness ≤50 nm and a diameter of 1-2 μm were dispersed in 500 mL of 3 mol / L NaOH solution; the solution was placed in a constant temperature magnetic stirrer and reacted in an 80℃ water bath at 800 rpm for 4 hours; the reaction solution was centrifuged at 12000 rpm for 10 min, and the precipitate was ultrasonically washed with deionized water; the wet material was transferred to a vacuum drying oven and dried at 120℃ for 4-6 h to obtain hydroxylated boron nitride (OH-BN); This step involves surface hydroxylation of h-BN nanosheets with NaOH. The core objective is to activate their inert surface and introduce hydrophilic hydroxyl groups. Under stirring conditions of 80℃ and 800 rpm, the NaOH solution reacts with h-BN for 4 hours, effectively exfoliating the nanosheets and covalently bonding hydroxyl groups to form hydroxylated boron nitride (OH-BN). This process significantly enhances the material's hydrophilicity and chemical reactivity, laying the foundation for subsequent grafting modification, while also improving its dispersibility in water and preventing aggregation.

[0009] S2: Grafting modification with compound modifier: 8-12 g of OH-BN was added to 500 mL of anhydrous ethanol and ultrasonically dispersed for 30 min to form a uniform suspension; 0.5 g (based on the total mass of KH-550 and NDZ-201) of the KH-550 / NDZ-201 compound modifier solution, which had been pre-mixed and allowed to stand for 30 min for activation, was added; the mixture was then subjected to mechanical stirring and ultrasonic reaction in a 60 ℃ constant temperature oil bath for 4-6 h; the modified product was filtered through a Buchner funnel, washed three times with ethanol, and vacuum dried at 60 ℃ for 12 h to obtain modified boron nitride mBN; This step involves surface grafting modification of OH-BN using a 3:1 mixture of KH-550 (silane coupling agent) and NDZ-201 (titanium ester coupling agent). Under ultrasonic-mechanical stirring conditions at 60℃, the amino and hydroxyl groups of KH-550 react to form chemical bonds, enhancing compatibility with polar polymers; while the titanate groups of NDZ-201 optimize dispersibility in non-polar resins. The synergistic effect of both significantly improves the interfacial bonding strength and uniformity of modified boron nitride (mBN) in the matrix, preventing particle agglomeration during processing. S3: PET Masterbatch: Formula: mBN 80~100 g; PET chips, viscosity 0.68 dL / g 350~380 g; sodium ethylenediaminetetramethylenephosphonate 10~15 g; styrene-maleic anhydride copolymer 5~10 g; antioxidant 1010 2~3 g; carbodiimide 2.5~5 g; Raw materials are dried at 110℃ for 4 hours by forced air drying, and then fed into a co-rotating twin-screw extruder through a loss-in-weight feeder. The twin-screw extruder has an L / D ratio of 40:1 and a screw diameter of 35 mm. Temperature zone settings: Zone 1 feeding section 220℃, Zone 2 melting section 240℃, Zone 3 mixing section 255℃, Zone 4 die head 250℃; Screw assembly: configured with 4 sets of kneading blocks with a 45° stagger angle and 2 sets of reverse screw elements, speed 300 rpm, melt pressure maintained at 12-15MPa; extruded strips are cooled in a water bath and then pelletized to a particle size of 2×3mm. This step involves co-extruding mBN with PET, sodium ethylenediaminetetramethylenephosphonate (EDTMP), and antioxidants, achieving uniform dispersion through the high shear force of a twin-screw extruder. EDTMP acts as a dispersant to further prevent mBN aggregation, while antioxidant 1010 improves the heat resistance of the masterbatch. The masterbatch process simplifies subsequent spinning steps, ensuring the stable presence of mBN in the matrix. Simultaneously, optimized screw assembly (4 sets of 45° kneading blocks + 2 sets of anti-screw elements) and temperature zoning (220-255℃) guarantee melt uniformity and processing stability.

[0010] S4: Polypropylene wax grafted with maleic anhydride (PPW-g-MAH): 25-35 g of polypropylene wax was heated to a molten state at 80-90℃, 2.2-2.5 g of maleic anhydride was added and stirred for 5 min, and 3 g of methyl methacrylate solution containing 0.004-0.006 g of dicumyl peroxide was added dropwise, and the reaction was stirred continuously for 30-60 min; the crude product was dissolved by reflux in 30 mL of 1,2-dichloroethane (DCE) at 80℃ for 1.5 h, then cooled to 50℃ and 80 mL of acetone was added to precipitate the product. The product was kept at a constant temperature of 50℃ in a water bath for 0.5 h, and then allowed to stand at room temperature for 1 h. After vacuum filtration and multiple acetone washings, the product was vacuum dried at 80℃ for 16 h to obtain the purified product PPW-g-MAH; In this step, the grafted product is selectively separated and purified by solvent through reflux and dissolution-precipitation, which thoroughly removes unreacted monomers and homopolymer impurities, ensuring the grafting rate of PPW-g-MAH. S5: PA6 resin system: Formulation: mBN 70~80 g, polypropylene wax grafted maleic anhydride 20~40 g, polypropylene grafted maleic anhydride 30~50 g; polyamide 6 280~320 g, maleic anhydride grafted POE 20~30 g; extruder temperature settings: Zone 1 230 ℃, Zone 2 245 ℃, Zone 3 255 ℃, Zone 4 250 ℃; high-shear screw is used, speed 280 rpm; after extrusion, vacuum devolatilization is carried out at -0.08MPa for 20 min, and then the melt is cut into elliptical particles with a major diameter of 3mm by an air-cooled granulator to obtain PA6 composite masterbatch; This step targets a polyamide 6 (PA6) matrix, using maleic anhydride-grafted POE as a compatibilizer. The anhydride groups react with the hydroxyl groups on the mBN surface, significantly enhancing interfacial bonding. High-shear screws and temperature control ensure uniform dispersion of mBN in PA6, avoiding defects. This step also involves customizing a masterbatch formulation suitable for polar resins, optimizing the balance between thermal conductivity and mechanical properties, and providing high-performance raw materials for subsequent spinning.

[0011] S6: Cooling Fiber Melt Spinning: 80-120 g of PET masterbatch is premixed with 380-420 g of PA6 composite masterbatch to obtain cooling functional masterbatch, which is dried at 120 ℃ for 8 h; it enters a screw spinning mill with a diameter of 30 mm, L / D=28:1, and temperature zones: feed section: 210 ℃, compression section: 240 ℃, metering section: 255 ℃, spinning box: 265 ℃; the melt is transported to the spinneret's 72 orifices (0.25 mm diameter) by a metering pump (0.6 cc / rev); key slow cooling zone design: a dual-channel temperature control system is set in the 30 cm area below the spinneret: upper 0-10 cm: 150 ℃ hot air circulation, wind speed of 0.3 m / s; lower 10-30 cm: gradient cooling to 80 ℃, cooling rate of 2.3 ℃ / cm; after the nascent fiber is cooled by side blowing, it is then spun at 1000... The fiber is pre-stretched at a speed of m / min, then stretched by hot rollers at a temperature of 90 ℃, and then heat-set at 130 ℃ for 30 s. The final winding speed is 2500 m / min. This yields a cooling fiber based on a modified boron nitride cooling functional masterbatch. This step controls the fiber structure by optimizing the spinning process: a slow cooling zone design (150°C hot air circulation at the top + gradient cooling to 80°C at the bottom) reduces thermal stress and promotes uniform crystallization; high spinning speed (2500m / min) and drawing process (800m / min pre-drawing + 60°C hot roller drawing) improve fiber orientation. Combined with the high thermal conductivity of mBN, the final fiber achieves rapid heat dissipation and excellent cooling effect while maintaining high strength and dimensional stability.

[0012] Preferably, in step S1, the amount of hexagonal boron nitride used is 20 g, and the drying time is 5 h; Preferably, in step S2, the amount of hydroxylated boron nitride used is 10 g, and the ultrasonic reaction time is 5 h; The specific steps for pre-static mixing and activation of the KH-550 / NDZ-201 compound modifier solution are as follows: add KH-550 and NDZ-201 at a ratio of 0.375g:0.125g to 2-3mL of anhydrous ethanol, stir magnetically for 10 minutes until a homogeneous solution is obtained, and let stand for 30 minutes to complete the ethoxy / alkoxy hydrolysis activation. Preferably, the formulation in step S3 is as follows: 90 g of mBN; 365 g of PET chips with a viscosity of 0.68 dL / g; 13 g of sodium ethylenediaminetetramethylenephosphonate; 8 g of styrene-maleic anhydride copolymer; 2.5 g of antioxidant 1010; and 4 g of carbodiimide. Preferably, in step S4, 30 g of polypropylene wax is heated to a molten state at 85 °C, 2.3 g of maleic anhydride is added, and 3 g of methyl methacrylate solution contains 0.005 g of dicumyl peroxide. The reaction time is 45 min.

[0013] Preferably, the formulation in step S5 is: 75 g mBN, 30 g polypropylene wax grafted with maleic anhydride, 40 g polypropylene grafted with maleic anhydride; 300 g polyamide 6, and 25 g maleic anhydride grafted with POE. Preferably, in step S6, 100 g of PET masterbatch and 400 g of PA6 composite masterbatch are premixed; The technological advancements achieved by this invention due to the adoption of the above technical solution are as follows: 1. In this invention, after grafting with a compound modifier, the modified boron nitride on its surface forms hydrogen bonds and van der Waals entanglements with the resin matrix, respectively, and is oriented along the fiber axis as a rigid nanoskeleton, directly improving the modulus and creep resistance; maleic anhydride grafted onto polypropylene wax forms imide bonds with the amino groups on the mBN surface through maleic anhydride groups, while polypropylene wax segments penetrate into the amorphous region of PA6, strengthening the interfacial stress transfer through "chemical-physical" double crosslinking; maleic anhydride grafting constructs an elastic network, which synergistically inhibits crack propagation with PPW-g-MAH, maintaining rigidity while toughening; and sodium ethylenediaminetetramethylenephosphonate stabilizes the PET molecular chain structure by chelating metal ions, ensuring the intrinsic strength of the matrix and optimizing mechanical properties.

[0014] 2. In this invention, modified boron nitride (mBN), polypropylene wax grafted with maleic anhydride (PPW-g-MAH), and maleic anhydride grafted with POE (POE-g-MAH) significantly enhance heat dissipation capacity through multi-dimensional synergistic effects: First, the hydroxylated and compounded modifier-modified mBN forms a high aspect ratio layered structure, constructing a three-dimensional continuous thermally conductive network in the polymer matrix, effectively reducing phonon scattering and improving in-plane / out-of-plane heat conduction efficiency; second, the polar grafted chains of PPW-g-MAH strengthen the compatibility of the filler-matrix interface through hydrogen bonding, reducing... Interfacial thermal resistance promotes stress transfer and heat conduction; furthermore, POE-g-MAH has both toughening and thermal conductivity functions, and its elastomer properties alleviate thermal stress between mBN and resin, while the MAH groups further optimize the continuity of the thermally conductive network; ultimately, the three work together to achieve efficient heat conduction: mBN constructs a thermally conductive framework, PPW-g-MAH and POE-g-MAH reduce thermal resistance through interfacial modification, the matrix resin provides structural support, and the dispersant ensures uniform distribution of fillers, together forming a low thermal resistance, high thermal conductivity composite system, significantly improving the heat dissipation performance of the material.

[0015] 3. In this invention, modified boron nitride (mBN) constructs a three-dimensional thermally conductive network. Its high aspect ratio layered structure rapidly conducts heat from the body surface along the in-plane / out-of-plane direction, reducing heat accumulation at the skin-material interface. Surface hydroxylation and compound modification agent (KH-550: NDZ-201) treatment enhance the hydrophilicity of the mBN surface, increasing the wetting area upon skin contact and promoting instantaneous heat exchange. Polypropylene wax grafted with maleic anhydride (PPW-g-MAH) acts as a compatibilizer, optimizing the interfacial bonding between mBN and the PA6 matrix and reducing interfacial thermal resistance in the heat conduction path. The elastomeric properties of maleic anhydride grafted with POE (POE-g-MAH) alleviate thermal stress and maintain the stability of the thermally conductive network. The synergistic effect of these mechanisms enables the material to rapidly dissipate heat from the body surface upon contact, and significantly improves the cooling sensation upon contact by optimizing surface properties and heat conduction paths. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a bar chart comparing the fracture strength of mechanical property test data of Embodiment 1 and Comparative Examples 1-3 of the present invention; Figure 2 The following is a bar chart comparing the thermal conductivity data obtained from Examples 2 and Comparative Examples 4-6 of this invention: Figure 3The bar chart shows the contact cooling sensation data of Embodiment 3 and Comparative Examples 7-9 of the present invention. Figure 4 The image shows a cross-sectional SEM image of the PA6 composite masterbatch (PA6 / mBN composite material) obtained in step S5 of Example 3 of this invention. Figure 5 This is a photograph of the PET masterbatch obtained in step S3 of Example 3; Figure 6 This is a photograph of the fibers obtained in Example 3. Detailed Implementation

[0018] To make the technical problem to be solved, the technical solution, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the content of this invention and are not intended to limit this invention.

[0019] In this invention, boron nitride (h-BN) was purchased from Henan Nitrogen-Boron New Material Technology Co., Ltd.; KH-550 was purchased from Nanjing Nengde New Material Technology Co., Ltd.; NDZ-201 was purchased from Wuhan Kanos Technology Co., Ltd.; PET chips were purchased from Dongguan Hebao Plastics Co., Ltd.; sodium ethylenediaminetetramethylphosphonate was purchased from Shandong Taihe Water Treatment Technology Co., Ltd.; antioxidant 1010 was purchased from Guangzhou Dayin New Material Co., Ltd.; polypropylene was purchased from Dongming Hengchang Chemical Co., Ltd.; maleic anhydride-grafted POE was purchased from Dongguan Nabaichuan Plastics Co., Ltd.; polypropylene wax was purchased from Shijiazhuang Tengchi Chemical Co., Ltd.; maleic anhydride (CAS 108-31-6) was purchased from Jinan Century Tongda Chemical Co., Ltd.; and polypropylene-grafted maleic anhydride was purchased from Dongguan Xingyuan Chemical Co., Ltd. Example 1

[0020] This embodiment illustrates how the mechanical properties are optimized through the synergistic effect of modified boron nitride, polypropylene wax grafted with maleic anhydride, and sodium ethylenediaminetetramethylenephosphonate. The specific implementation steps are as follows: S1: Boron nitride hydroxylation pretreatment: 20 g of hexagonal boron nitride (h-BN) nanosheets with a thickness ≤50 nm and a diameter of 1-2 μm were dispersed in 500 mL of 3 mol / L NaOH solution; the solution was placed in a constant temperature magnetic stirrer and reacted in an 80℃ water bath at 800 rpm for 4 hours; the reaction solution was centrifuged at 12000 rpm for 10 min, and the precipitate was ultrasonically washed with deionized water; the wet material was transferred to a vacuum drying oven and dried at 120℃ for 5 h to obtain hydroxylated boron nitride (OH-BN); S2: Grafting modification with compound modifier: 10 g OH-BN was added to 500 mL anhydrous ethanol and ultrasonically dispersed for 30 min to form a uniform suspension; 0.5 g of compound modifier KH-550:NDZ-201 (3:1) was added after being pre-mixed and activated by standing for 30 min; the mixture was then stirred mechanically and ultrasonically reacted in a 60℃ constant temperature oil bath for 5 h; the modified product was filtered through a Buchner funnel, washed three times with ethanol, and vacuum dried at 60℃ for 12 h to obtain modified boron nitride mBN; the specific steps for pre-activation of the KH-550 / NDZ-201 compound modifier solution were as follows: KH-550 and NDZ-201 were added to 3 mL anhydrous ethanol at a ratio of 0.375 g:0.125 g and magnetically stirred for 10 min to form a homogeneous solution, and then allowed to stand for 30 min to complete the ethoxy / alkoxy hydrolysis activation; S3: PET Masterbatch: Formula: mBN 90 g; PET chips, viscosity 0.68 dL / g 365 g; sodium ethylenediaminetetramethylenephosphonate 13 g; styrene-maleic anhydride copolymer 8 g; antioxidant 1010 2.5 g; carbodiimide 4 g; Raw materials are dried at 110℃ for 4 hours by forced air drying, and then fed into a co-rotating twin-screw extruder through a loss-in-weight feeder. The twin-screw extruder has an L / D ratio of 40:1 and a screw diameter of 35 mm. Temperature zone settings: Zone 1 feeding section 220 ℃, Zone 2 melting section 240 ℃, Zone 3 mixing section 255 ℃, Zone 4 die head 250 ℃; Screw assembly: configured with 4 sets of kneading blocks with a 45° stagger angle and 2 sets of reverse screw elements, rotation speed 300 rpm, melt pressure maintained at 13 MPa; The extruded strip is cooled in a water bath and then granulated, with a particle size of 2×3 mm. S4: Polypropylene wax grafted with maleic anhydride: 30 g of polypropylene wax was heated to 85℃ and melted. 2.3 g of maleic anhydride was added and stirred for 5 min. 3 g of methyl methacrylate solution containing 0.005 g of dicumyl peroxide was added dropwise, and the reaction was continued with stirring for 45 min. The crude product was dissolved in 30 mL of 1,2-dichloroethane (DCE) under reflux at 80℃ for 1.5 h. The solution was then cooled to 50℃ and 80 mL of acetone was added to precipitate the product. The solution was kept in a constant temperature water bath at 50℃ for 0.5 h and then allowed to stand at room temperature for 1 h. After vacuum filtration and multiple acetone washes, the product was vacuum dried at 80℃ for 16 h to obtain the purified product PPW-g-MAH. S5: PA6 resin system: Formulation: mBN 75 g, polypropylene wax grafted maleic anhydride 30 g, polypropylene grafted maleic anhydride 40 g; polyamide 6 300 g, maleic anhydride grafted POE 25 g; extruder temperature settings: zone 1 230 ℃, zone 2 245 ℃, zone 3 255 ℃, zone 4 250 ℃; high shear screw with a speed of 280 rpm; after extrusion, vacuum devolatilization is performed at -0.08MPa for 20 min, and then the melt is cut into elliptical particles with a major diameter of 3 mm by an air-cooled granulator to obtain PA6 composite masterbatch; S6: Cooling Fiber Melt Spinning: 100 g of PET masterbatch and 400 g of PA6 composite masterbatch are premixed to obtain cooling functional masterbatch, which is dried at 120 ℃ for 8 h; it enters a screw spinning mill with a diameter of 30 mm, L / D=28:1, and temperature zones: feeding section: 210 ℃, compression section: 240 ℃, metering section: 255 ℃, spinning box: 265 ℃; the melt is delivered to the spinneret's 72 orifices (0.25 mm diameter) by a metering pump (0.6 cc / rev); key slow cooling zone design: a dual-channel temperature control system is set in the 30 cm area below the spinneret: upper 0-10 cm: 150 ℃ hot air circulation, wind speed of 0.3 m / s; lower 10-30 cm: gradient cooling to 80 ℃, cooling rate of 2.3 ℃ / cm; after the nascent fiber is cooled by side blowing, it is then spun at 1000... The material is pre-stretched at a speed of m / min, then stretched by hot rollers at a temperature of 90 ℃, and then heat-set at 130 ℃ for 30 s. The final winding speed is 2500 m / min. This yields a cooling functional masterbatch based on modified boron nitride and its fiber.

[0021] Comparative Example 1: In steps S3 and S5, the modified boron nitride was replaced with hexagonal boron nitride (h-BN), and all other steps were the same as in Example 1; Comparative Example 2: In step S5, polypropylene wax grafted with maleic anhydride was replaced with an equal amount of polypropylene grafted with maleic anhydride, and the other steps were the same as in Example 1. Comparative Example 3: In step S3, sodium ethylenediaminetetramethylenephosphonate (EDTMPS) was replaced with hydroxyethylidene diphosphonic acid (HEDP), and all other steps were the same as in Example 1; Hydroxyethylidene diphosphonic acid (HEDP) belongs to the same organophosphonic acid class as EDTMPS and has chelating and dispersing functions; it is suitable for determining whether the polyphosphonic acid groups in EDTMPS are key to synergistic enhancement; hydroxyethylidene diphosphonic acid was purchased from Shandong Taihe Water Treatment Technology Co., Ltd.

[0022] Mechanical property testing: Tests were conducted according to GB / T 1040.2-2022 standard using a computer-controlled electronic universal testing machine (SANS-CMT6104). Standard dumbbell-shaped specimens were prepared from the cooling functional masterbatches of Examples 1 and Comparative Examples 1-3 using an extrusion process; the gauge length was 75 mm, the width was 10 mm, and the thickness was 4 mm. The specimens were pretreated in a constant temperature and humidity chamber for 24 hours to eliminate internal stress. The tensile speed was set to 50 mm / min, and recording was continued until the specimen fractured. The maximum tensile force (F) was recorded synchronously using the testing machine software. max ), elongation at break (ΔL) and stress-strain curves in the elastic stage;

[0023] Fracture strength (σ): σ = F max / (b·d) Where b is the sample width (10 mm) and d is the thickness (4 mm). Elongation at break (ε): ε = ∆L / L0 × 100% Where L0 is the original gauge length (75mm).

[0024] The elastic modulus is the slope of the linear segment of the stress-strain curve.

[0025] The calculated data is recorded in Table 1: Table 1 Mechanical property test data of Example 1 and Comparative Examples 1-3

[0026] The experimental data show that the fibers prepared by the synergistic effect of modified boron nitride, polypropylene wax grafted with maleic anhydride and sodium ethylenediaminetetramethylenephosphonate have the best mechanical properties. Example 2

[0027] This embodiment illustrates that the present invention can significantly enhance heat dissipation capacity through multi-dimensional synergistic effects of modified boron nitride (mBN), polypropylene wax grafted with maleic anhydride (PPW-g-MAH), and maleic anhydride grafted with POE (POE-g-MAH). The specific implementation steps are as follows: S1: Boron nitride hydroxylation pretreatment: 15 g of hexagonal boron nitride (h-BN) nanosheets with a thickness ≤50 nm and a diameter of 1-2 μm were dispersed in 500 mL of 3 mol / L NaOH solution; the solution was placed in a constant temperature magnetic stirrer and reacted in an 80℃ water bath at 800 rpm for 4 hours; the reaction solution was centrifuged at 12000 rpm for 10 min, and the precipitate was ultrasonically washed with deionized water; the wet material was transferred to a vacuum drying oven and dried at 120℃ for 4 h to obtain hydroxylated boron nitride (OH-BN); S2: Grafting modification with compound modifier: 8 g of OH-BN was added to 500 mL of anhydrous ethanol and ultrasonically dispersed for 30 min to form a uniform suspension; 0.5 g of compound modifier KH-550:NDZ-201 (3:1) was added after being pre-mixed and activated by standing for 30 min; the mixture was then stirred mechanically and ultrasonically reacted in a 60℃ constant temperature oil bath for 4 h; the modified product was filtered through a Buchner funnel, washed three times with ethanol, and vacuum dried at 60℃ for 12 h to obtain modified boron nitride mBN; the specific steps for pre-activation of the KH-550 / NDZ-201 compound modifier solution were as follows: KH-550 and NDZ-201 were added to 3 mL of anhydrous ethanol at a ratio of 0.375 g:0.125 g, and magnetically stirred for 10 min until a homogeneous solution was obtained; the solution was then allowed to stand for 30 min to complete the ethoxy / alkoxy hydrolysis activation; S3: PET Masterbatch: Formula: mBN 80 g; PET chips, viscosity 0.68 dL / g 350 g; sodium ethylenediaminetetramethylenephosphonate 10 g; styrene-maleic anhydride copolymer 5 g; antioxidant 1010 2 g; carbodiimide 2.5 g; The raw materials are dried at 110℃ for 4 hours by forced air and fed into a co-rotating twin-screw extruder through a loss-in-weight feeder. The twin-screw extruder has an L / D ratio of 40:1 and a screw diameter of 35 mm. Temperature zone settings: Zone 1 feeding section 220 ℃, Zone 2 melting section 240 ℃, Zone 3 mixing section 255 ℃, Zone 4 die head 250 ℃; Screw assembly: configured with 4 sets of kneading blocks with a 45° stagger angle and 2 sets of reverse screw elements, rotation speed 300 rpm, melt pressure maintained at 12-15 MPa; The extruded strip is cooled in a water bath and then granulated to a particle size of 2×3 mm. S4: Polypropylene wax grafted with maleic anhydride: 25 g of polypropylene wax was heated to 80℃ and melted. 2.2 g of maleic anhydride was added and stirred for 5 min. 3 g of methyl methacrylate solution containing 0.004 g of dicumyl peroxide was added dropwise, and the reaction was stirred continuously for 30 min. The crude product was dissolved in 30 mL of 1,2-dichloroethane (DCE) under reflux at 80℃ for 1.5 h. The solution was then cooled to 50℃ and 80 mL of acetone was added to precipitate the product. The solution was kept in a constant temperature water bath at 50℃ for 0.5 h and then allowed to stand at room temperature for 1 h. After vacuum filtration and multiple acetone washes, the product was vacuum dried at 80℃ for 16 h to obtain the purified product PPW-g-MAH. S5: Resin system: PA6 formulation: mBN 70 g, polypropylene wax grafted maleic anhydride 20 g, polypropylene grafted maleic anhydride 30 g; polyamide 6 280 g, maleic anhydride grafted POE 20 g; extruder temperature settings: zone 1 230 ℃, zone 2 245 ℃, zone 3 255 ℃, zone 4 250 ℃; high shear screw is used, speed 280 rpm; after extrusion, vacuum devolatilization is carried out at -0.08MPa for 20 min, and then the melt is cut into elliptical particles with a major diameter of 3 mm by an air-cooled granulator to obtain PA6 composite masterbatch; S6: Cooling Fiber Melt Spinning: 80 g of PET masterbatch and 380 g of PA6 composite masterbatch are premixed to obtain cooling functional masterbatch, which is dried at 120 ℃ for 8 h; it enters a screw spinning mill with a diameter of 30 mm, L / D=28:1, and temperature zones: feeding section: 210 ℃, compression section: 240 ℃, metering section: 255 ℃, spinning box: 265 ℃; the melt is transported to the spinneret's 72 orifices (0.25 mm diameter) by a metering pump (0.6 cc / rev); key slow cooling zone design: a dual-channel temperature control system is set in the 30 cm area below the spinneret: upper 0-10 cm: 150 ℃ hot air circulation, wind speed of 0.3 m / s; lower 10-30 cm: gradient cooling to 80 ℃, cooling rate of 2.3 ℃ / cm; after the nascent fiber is cooled by side blowing, it is then spun at 1000... The material is pre-stretched at a speed of m / min, then stretched by hot rollers at a temperature of 90 ℃, and then heat-set at 130 ℃ for 30 s. The final winding speed is 2500 m / min. This yields a cooling functional masterbatch based on modified boron nitride and its fiber.

[0028] Comparative Example 4: In steps S3 and S5, the modified boron nitride was replaced with hexagonal boron nitride, and the other steps were the same as in Example 2; Comparative Example 5: In step S5, polypropylene wax grafted with maleic anhydride was replaced with an equal amount of polypropylene grafted with maleic anhydride, and the other steps were the same as in Example 2. Comparative Example 6: In step S5, pure polyolefin elastomer was used instead of maleic anhydride-grafted POE, and all other steps were the same as in Example 2. Among them, the polyolefin elastomer (W1-801) was purchased from Wanhua Chemical Group Co., Ltd. Thermal conductivity testing: The thermal conductivity of the cooling functional masterbatch was tested according to ASTM E1461 standard; a laser flare thermal conductivity meter (Netzsch LFA 467) equipped with an Nd:YAG laser (wavelength 1064nm) and an infrared detector was used for testing. The cooling functional masterbatches prepared in Examples 2 and 4-6 were dried in a vacuum drying oven at 80°C for 4 hours. After cooling, they were premixed with additives and dispersed in a solvent to ensure uniformity. The tableting temperature was set to 310°C, the pressure was controlled at 120 MPa, and the holding time was 4 minutes. After tableting, the tablets were slowly cooled. A graphite layer of ≤5 μm was sprayed onto the surface of the tablets, which were then cut into tablets with a diameter of 12.7 mm and a thickness of 2 mm. The tablets were dried again at 80°C for 4 hours. The laser energy was adjusted to 8 J / cm², and the sample was placed on the sample holder, ensuring that the laser irradiation surface was perpendicular to the detector. A laser pulse (pulse width 0.5 ms) was emitted, and the temperature rise curve on the back of the sample was recorded. The temperature range was from room temperature to 150°C, with each 50°C test point. The tests were conducted in a nitrogen atmosphere. The calculated thermal conductivity data are recorded in Table 2. The formula for calculating the thermal diffusivity is: α = 0.1388·(d² / t) 1 / 2 ) Where d is the sample thickness (m), t 1 / 2 The time (s) required for the temperature to rise to half of its maximum value; Thermal conductivity calculation formula: λ = α·ρ·c p Where ρ is density (measured according to Archimedes' method), c p For specific heat (DSC test) Table 2 shows the thermal conductivity data obtained from Examples 2 and Comparative Examples 4-6.

[0029]

[0030] Based on the data obtained in this experiment, it can be seen that modified boron nitride (mBN), polypropylene wax grafted with maleic anhydride (PPW-g-MAH), and maleic anhydride grafted with POE (POE-g-MAH) can significantly enhance heat dissipation capacity through multi-dimensional synergistic effects. Example 3:

[0031] This embodiment illustrates the synergistic effect of modified boron nitride (mBN), polypropylene wax grafted with maleic anhydride, and maleic anhydride grafted with POE, enabling the material to rapidly dissipate heat from the body surface upon contact. Furthermore, by optimizing surface properties and heat conduction paths, the cooling sensation upon contact can be significantly enhanced.

[0032] The specific implementation steps are as follows: S1: Boron nitride hydroxylation pretreatment: 25 g of hexagonal boron nitride (h-BN) nanosheets with a thickness ≤50 nm and a diameter of 1-2 μm were dispersed in 500 mL of 3 mol / L NaOH solution; the solution was placed in a constant temperature magnetic stirrer and reacted in an 80℃ water bath at 800 rpm for 4 hours; the reaction solution was centrifuged at 12000 rpm for 10 min, and the precipitate was ultrasonically washed with deionized water; the wet material was transferred to a vacuum drying oven and dried at 120℃ for 6 h to obtain hydroxylated boron nitride (OH-BN); S2: Grafting modification with compound modifier: 12 g OH-BN was added to 500 mL anhydrous ethanol and ultrasonically dispersed for 30 min to form a uniform suspension; 0.5 g of compound modifier KH-550:NDZ-201 (3:1) was added after being pre-mixed and activated by standing for 30 min; the mixture was then stirred mechanically and ultrasonically reacted in a 60℃ constant temperature oil bath for 6 h; the modified product was filtered through a Buchner funnel, washed three times with ethanol, and vacuum dried at 60 ℃ for 12 h to obtain modified boron nitride mBN; the specific steps for pre-activation of the KH-550 / NDZ-201 compound modifier solution were as follows: KH-550 and NDZ-201 were added to 3 mL anhydrous ethanol at a ratio of 0.375 g:0.125 g and magnetically stirred for 10 min until a homogeneous solution was obtained, and then allowed to stand for 30 min to complete the ethoxy / alkoxy hydrolysis activation; S3: PET Masterbatch: Formula: mBN 100 g; PET chips, viscosity 0.68 dL / g 380 g; sodium ethylenediaminetetramethylenephosphonate 15 g; styrene-maleic anhydride copolymer 10 g; antioxidant 1010 3 g; carbodiimide 5 g; Raw materials are dried at 110℃ for 4 hours by forced air drying, and then fed into a co-rotating twin-screw extruder via a loss-in-weight feeder. The twin-screw extruder has an L / D ratio of 40:1 and a screw diameter of 35 mm. Temperature zone settings: Zone 1 feeding section 220℃, Zone 2 melting section 240℃, Zone 3 mixing section 255℃, Zone 4 die head 250℃. ℃; Screw assembly: configured with 4 sets of kneading blocks with a staggered angle of 45° and 2 sets of reverse screw elements, rotation speed 300 rpm, melt pressure maintained at 12-15 MPa; extruder strips are granulated after cooling in a water bath, with a particle size of 2×3 mm; a physical image of the PET masterbatch obtained in this embodiment is shown below. Figure 5 As shown; S4: Polypropylene wax grafted with maleic anhydride: 35 g of polypropylene wax was heated to 90℃ and melted. 2.5 g of maleic anhydride was added and stirred for 5 min. 3 g of methyl methacrylate solution containing 0.006 g of dicumyl peroxide was added dropwise, and the reaction was stirred continuously for 60 min. The crude product was dissolved in 30 mL of 1,2-dichloroethane (DCE) under reflux at 80℃ for 1.5 h. The solution was then cooled to 50℃ and 80 mL of acetone was added to precipitate the product. The solution was kept in a constant temperature water bath at 50℃ for 0.5 h and then allowed to stand at room temperature for 1 h. After vacuum filtration and multiple acetone washes, the product was vacuum dried at 80℃ for 16 h to obtain the purified product PPW-g-MAH. S5: PA6 resin system: Formulation: mBN 80 g, polypropylene wax grafted maleic anhydride 40 g, polypropylene grafted maleic anhydride 50 g; polyamide 6 320 g, maleic anhydride grafted POE 30 g; extruder temperature settings: zone 1 230 ℃, zone 2 245 ℃, zone 3 255 ℃, zone 4 250 ℃; high shear screw with a speed of 280 rpm; after extrusion, vacuum devolatilization is performed at -0.08MPa for 20 min, and then the melt is cut into elliptical particles with a major diameter of 3 mm by an air-cooled granulator to obtain PA6 composite masterbatch; S6: Cooling Fiber Melt Spinning: 120 g of PET masterbatch and 420 g of PA6 composite masterbatch are premixed to obtain cooling functional masterbatch, which is dried at 120 ℃ for 8 h; it enters a screw spinning mill with a diameter of 30 mm, L / D=28:1, and temperature zones: feed section: 210 ℃, compression section: 240 ℃, metering section: 255 ℃, spinning box: 265 ℃; the melt is transported to the 72 orifices of the spinneret by a metering pump (0.6 cc / rev), with an orifice diameter of 0.25 mm; key slow cooling zone design: a dual-channel temperature control system is set in the 30 cm area below the spinneret: upper 0-10 cm: 150 ℃ hot air circulation, wind speed of 0.3 m / s; lower 10-30 cm: gradient cooling to 80 ℃, cooling rate of 2.3 ℃ / cm; after the nascent fiber is cooled by side blowing, it is then spun at 1000 The fiber is pre-stretched at a speed of m / min, then heat-set at 130℃ for 30 s after hot rolling at 90℃, and finally wound at a speed of 2500 m / min; thus, a cooling functional masterbatch based on modified boron nitride and its fiber are obtained. A physical image of the fiber obtained in this embodiment is shown below. Figure 6 As shown.

[0033] Comparative Example 7: In steps S3 and S5, the modified boron nitride was replaced with hexagonal boron nitride, and the other steps were the same as in Example 3; Comparative Example 8: In step S5, polypropylene wax grafted with maleic anhydride was replaced with an equal amount of polypropylene grafted with maleic anhydride, and the other steps were the same as in Example 3. Comparative Example 9: In step S5, pure polyolefin elastomer was used instead of maleic anhydride-grafted POE; all other steps were the same as in Example 3.

[0034] The cooling sensation upon contact was tested according to GB / T 35263-2017 standard. The cooling performance at the moment of contact was evaluated by measuring the maximum heat flux (Q-max value) when the material came into contact with artificial skin (thermal water jacket). A higher Q-max value indicates stronger thermal conductivity and a more significant cooling sensation. A cooling sensation tester (KES-F7) was used, with the heat flux meter calibrated to ±0.01 W / cm², and the artificial skin temperature controlled at 32±0.5℃. Cooling fibers made from the cooling functional masterbatches prepared in Examples 2 and 4-6 were woven into 40S plain knit fabrics, washed three times, and conditioned at 25℃ / 65%RH for 24 hours before being cut into 10×10cm samples. The sample was laid flat on the test stage, and a pressure of 1.96 kPa (simulating light touch pressure) was applied for 5 seconds. The maximum heat flow rate (Q-max value) output by the heat flow meter was recorded. The test was repeated 5 times and the average value was taken. The obtained data are recorded in Table 3. Table 3. Contact cooling sensation data for Examples 3 and Comparative Examples 7-9

[0035]

[0036] The experimental data shows that the fiber material prepared in Example 3 has the largest Q-max value, indicating that the material prepared in Example 3 has the best cooling sensation upon contact. This proves that the synergistic effect of modified boron nitride (mBN), polypropylene wax grafted with maleic anhydride, and maleic anhydride grafted with POE can significantly improve the cooling sensation upon contact.

[0037] Figure 4 The image shows a cross-sectional SEM image of the PA6 composite masterbatch (PA6 / mBN composite material) obtained in step S5 of Example 3 of this invention. As can be seen from the image, the mBN particles are well dispersed in PA6, and their plate-like structure forms a directional thermal conductive pathway in the PA6 matrix, which indirectly proves that modified boron nitride can work synergistically with PA6 to improve the cooling sensation upon contact.

Claims

1. A cooling functional masterbatch based on modified boron nitride, characterized in that, A premix consisting of 80-120 parts by weight of PET masterbatch and 380-420 parts by weight of PA6 composite masterbatch, the cooling functional masterbatch is used for subsequent melt spinning; The PET masterbatch comprises: modified boron nitride mBN, PET chips, and sodium ethylenediaminetetramethylenephosphonate; wherein, the modified boron nitride mBN is prepared by: boron nitride hydroxylation pretreatment and graft modification with compound modifier; The preparation of PA6 composite masterbatch includes: grafting maleic anhydride onto polypropylene wax and preparing PA6 resin system.

2. The cooling functional masterbatch based on modified boron nitride according to claim 1, characterized in that: The compound modifier is a mixture of silane coupling agent and titanate coupling agent in a 3:1 ratio.

3. The cooling functional masterbatch based on modified boron nitride according to claim 2, characterized in that: The boron nitride hydroxylation pretreatment steps are as follows: 15~25 g of hexagonal boron nitride (h-BN) nanosheets with a thickness ≤50 nm and a diameter of 1-2 μm are dispersed in 500 mL of 3 mol / L NaOH solution; the solution is placed in a constant temperature magnetic stirrer and reacted in an 80℃ water bath at 800 rpm for 4 hours; the reaction solution is centrifuged at 12000 rpm for 10 min, and the precipitate is ultrasonically washed with deionized water; the wet material is transferred to a vacuum drying oven and dried at 120℃ for 4~6 h to obtain hydroxylated boron nitride (OH-BN).

4. The cooling functional masterbatch based on modified boron nitride according to claim 3, characterized in that: The method for grafting modification with compound modifier is as follows: 8-12 g of OH-BN is added to 500 mL of anhydrous ethanol and ultrasonically dispersed for 30 min to form a uniform suspension; 0.5 g of compound modifier that has been pre-mixed and allowed to stand for 30 min for activation is added; the mixture is then stirred mechanically and ultrasonically reacted in a 60 ℃ constant temperature oil bath for 4-6 h; the modified product is filtered through a Buchner funnel, washed three times with ethanol, and vacuum dried at 60 ℃ for 12 h to obtain modified boron nitride mBN.

5. A cooling functional masterbatch based on modified boron nitride according to claim 4, characterized in that: The amount of hydroxylated boron nitride used is 10 g, and the ultrasonic reaction time is 5 h. The specific steps for pre-static mixing and activation are as follows: KH-550 and NDZ-201 are added to 2-3 mL of anhydrous ethanol at a ratio of 0.375 g: 0.125 g, and the mixture is magnetically stirred for 10 minutes until a homogeneous solution is obtained. The mixture is then allowed to stand for 30 minutes to complete the ethoxy / alkoxy hydrolysis activation.

6. The cooling functional masterbatch based on modified boron nitride according to claim 4, characterized in that: The PET masterbatch preparation method is as follows: Masterbatch formula: mBN 80~100 g; PET chips 350~380 g, viscosity 0.68 dL / g; sodium ethylenediaminetetramethylenephosphonate 10~15 g; styrene-maleic anhydride copolymer 5~10 g; antioxidant 1010 2~3 g; carbodiimide 2.5~5 g; the raw materials are dried at 110℃ for 4 hours by forced air drying, and then fed into a co-rotating twin-screw extruder through a loss-in-weight feeder. The twin-screw extruder has an L / D ratio of 40:1 and a screw diameter of 35 mm. Temperature zone settings: Zone 1 feeding section 220 ℃, Zone 2 melting section 240 ℃, Zone 3 mixing section 255 ℃, Zone 4 die head 250 ℃; Screw assembly: configured with 4 sets of kneading blocks with a 45° stagger angle and 2 sets of reverse screw elements, speed 300 rpm. At rpm, the melt pressure is maintained at 12-15 MPa; the extruded strip is cooled in a water bath and then granulated to a particle size of 2×3 mm.

7. The cooling functional masterbatch based on modified boron nitride according to claim 6, characterized in that: The masterbatch formulation consists of 90 g of mBN, 365 g of PET chips with a viscosity of 0.68 dL / g, 13 g of sodium ethylenediaminetetramethylenephosphonate, and 2.5 g of antioxidant 1010.

8. A cooling functional masterbatch based on modified boron nitride according to claim 4, characterized in that: The method for grafting maleic anhydride onto polypropylene wax is as follows: 25-35 g of polypropylene wax is heated to a molten state at 80-90℃, 2.2-2.5 g of maleic anhydride is added and stirred for 5 min, and 3 g of methyl methacrylate solution containing 0.004-0.006 g of dicumyl peroxide is added dropwise, and the reaction is continuously stirred for 30-60 min. The crude product is dissolved by reflux in 30 mL of 1,2-dichloroethane (DCE) at 80℃ for 1.5 h, then cooled to 50℃ and 80 mL of acetone is added to precipitate the product. The product is kept at a constant temperature of 50℃ in a water bath for 0.5 h and allowed to stand for 1 h. After vacuum filtration and multiple acetone washings, the product is vacuum dried at 80℃ for 16 h to obtain the purified product PPW-g-MAH.

9. A cooling functional masterbatch based on modified boron nitride according to claim 8, characterized in that: Preparation of PA6 resin system: Formula: mBN 70~80 g, polypropylene wax grafted with maleic anhydride 20~40 g, polypropylene grafted with maleic anhydride 30~50 g. Polyamide 6 280~320 g, maleic anhydride grafted POE 20~30 g; extruder temperature settings: zone 1 230 ℃, zone 2 245 ℃, zone 3 255 ℃, zone 4 250 ℃; high shear screw with a speed of 280 rpm; after extrusion, vacuum devolatilization is carried out at -0.08MPa for 20 min, and then the melt is cut into elliptical particles with a major diameter of 3mm by an air-cooled granulator to obtain PA6 composite masterbatch.

10. A method for preparing cooling fibers based on a cooling functional masterbatch based on modified boron nitride as described in any one of claims 1-9, characterized in that: The melt spinning method for cooling fibers is as follows: 80-120 g of PET masterbatch is premixed with 380-420 g of PA6 composite masterbatch to obtain the cooling functional masterbatch, which is then dried at 120 ℃ for 8 h. The masterbatch is then fed into a screw spinning mill (30 mm diameter, L / D = 28:1), with temperature zones: feed section: 210 ℃, compression section: 240 ℃, metering section: 255 ℃, spinning box: 265 ℃. The melt is pumped to the 72 orifices of the spinneret (0.25 mm diameter) via a metering pump. A key slow cooling zone is designed: a dual-channel temperature control system is installed in the 30 cm area below the spinneret: upper 0-10 cm: 150 ℃ hot air circulation at a speed of 0.3 m / s; lower 10-30 cm: gradient cooling to 80 ℃ at a cooling rate of 2.3 ℃ / cm. After being cooled by side blowing, the nascent fibers are then... The fiber is pre-stretched at a speed of m / min, then stretched by hot rollers at a temperature of 90 ℃, and then heat-set at 130 ℃ for 30 s. The final winding speed is 2500 m / min. This yields a cooling fiber based on a modified boron nitride cooling functional masterbatch.

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