Polyester fabric with moisture absorption, quick drying and cool touch

Abstract

The application provides a polyester fabric with moisture absorption and quick drying and cool touch, and belongs to the technical field of fabrics.The fabric is formed by modified polyester fibers with a radial three-layer structure, and comprises, from outside to inside, an outer hydrophilic layer with a polydopamine transition layer and an amphoteric ion polymer grafting layer formed on the surface, a moisture guiding layer in continuous pores formed by dissolving out of a water-soluble polymer pore-forming component, and an inner heat conducting layer containing dispersed and fixed sheet-shaped hexagonal boron nitride nanosheets.The fabric is prepared by composite spinning, water washing pore forming and surface radical grafting.The application realizes coupling regulation and control of rapid water adsorption, continuous migration and efficient heat diffusion, and has excellent moisture absorption, quick drying, cool touch and washing stability.

Description

Technical Field

[0001] This invention belongs to the field of fabric technology, and in particular relates to a polyester fabric with moisture-wicking, quick-drying and cool-to-the-touch properties. Background Technology

[0002] Polyester fibers are widely used in modern clothing and functional textiles due to their excellent mechanical strength, abrasion resistance, wrinkle resistance, and good processing performance. However, the lack of hydrophilic functional groups in polyester macromolecular chains and their high crystallinity result in polyester fabrics having strong hydrophobicity and extremely poor moisture absorption and breathability. During wear, sweat excreted by the human body is difficult to be quickly absorbed and conducted by the fabric, easily accumulating in the microclimate zone where the skin contacts the fabric, producing a stuffy and sticky feeling. At the same time, traditional polyester fibers have low thermal conductivity, making it difficult to quickly dissipate the heat released by the human body and failing to produce a cooling sensation upon contact. As consumers' demands for clothing comfort continue to increase, developing multifunctional polyester fabrics that combine highly efficient moisture absorption and quick-drying with a cool touch has become a research hotspot and consumer trend in the textile and apparel industry.

[0003] Currently, the main technologies for improving the moisture absorption and quick-drying properties of polyester fabrics on the market focus on two aspects: physical cross-section modification and chemical finishing. Physical cross-section modification mainly involves using specially shaped spinnerets to prepare polyester fibers into irregular cross-sections such as cross-shaped, Y-shaped, or multi-grooved sections. This method utilizes the capillary effect generated by the micron-level grooves formed on the fiber surface, enabling water to diffuse and migrate rapidly within the grooves. However, the physical capillary effect generated by the irregular cross-section alone cannot change the hydrophobic nature of the polyester fiber itself. The initial wetting angle of liquid water on the fiber surface remains relatively large, making it difficult for water to be quickly captured upon contact, resulting in a significant water absorption lag. Chemical finishing methods involve padding or coating with hydrophilic finishing agents to form a hydrophilic film on the fabric surface. Although this method can significantly improve the wettability of the fiber surface, the bonding force between the finishing agent and the polyester fiber is usually weak, relying only on physical adsorption or weak force anchoring. After repeated daily washing and friction, the hydrophilic coating is prone to peeling off and failure, leading to a sharp decline in moisture absorption performance. In addition, an excessively thick finishing coating can clog the fabric's gaps, damaging the fabric's original breathability and feel.

[0004] In the development of cool-feel fabrics, existing technologies mainly rely on adding high thermal conductivity inorganic fillers to the polyester matrix or coating the surface with cooling finishing agents. High thermal conductivity inorganic fillers are typically directly incorporated into polyester chips during melt spinning, utilizing the high thermal conductivity of inorganic particles to improve the overall heat transfer rate of the fiber. However, in traditional spinning processes, inorganic fillers are randomly dispersed, making it difficult to form continuous and efficient heat conduction pathways within the fiber. This limits heat transfer efficiency and the cooling effect. Blindly increasing the amount of filler added in pursuit of a higher contact cooling coefficient can easily lead to increased pressure differential in the spinning assembly, deterioration of melt rheology, and frequent yarn breakage. It can also severely damage the tensile strength of the fiber, making the fabric feel stiff and rough, and compromising wearing comfort.

[0005] More importantly, when integrating the two functions of moisture-wicking and quick-drying with a cooling sensation, existing technologies often face the dilemma of mutual constraints and poor synergy. The inorganic fillers introduced in large quantities to enhance the cooling sensation are usually highly hydrophobic or inert, which further exacerbates the hydrophobic characteristics of polyester fibers, leading to a significant reduction in the fabric's moisture absorption and wicking capabilities. On the other hand, the hydrophilic organic finishing coatings applied to improve moisture absorption typically have extremely low thermal conductivity, acting like an insulating layer on the fabric surface, severely hindering heat conduction between the inorganic fillers and the skin, thus greatly diminishing the cooling effect. Therefore, existing technologies struggle to truly achieve efficient synergy between moisture-wicking and quick-drying and a cooling sensation while ensuring the fabric's washability and processability, which greatly limits the further promotion and application of high-performance functional polyester fabrics. Summary of the Invention

[0006] The first objective of this invention is to provide a polyester fabric with moisture-wicking, quick-drying, and cool-to-the-touch properties, wherein the polyester fabric is formed of modified polyester fibers, and the modified polyester fibers sequentially include an outer hydrophilic layer, a middle moisture-wicking layer, and an inner thermally conductive layer in the radial direction. The outer hydrophilic layer is formed on the surface of the polyester fiber and includes a polydopamine transition layer and a zwitterionic polymer graft layer formed on the surface of the polydopamine transition layer; the thickness of the outer hydrophilic layer is 50-500 nm, wherein the thickness of the zwitterionic polymer graft layer accounts for 30%-80% of the total thickness of the outer hydrophilic layer; The middle moisture-conducting layer is located between the outer hydrophilic layer and the inner thermally conductive layer, and is composed of a continuous pore structure formed inside the modified polyester fiber; the pores are formed by removing water-soluble polymer pore-forming components dispersed in the modified polyester fiber after washing and dissolving, and the average pore size of the pores is 50nm-5μm. The inner thermal conductive layer comprises modified polyester fibers and sheet-like hexagonal boron nitride nanosheets dispersed and fixed in the polyester fibers. The mass of the hexagonal boron nitride nanosheets accounts for 1%-10% of the mass of the modified polyester fibers in the inner thermal conductive layer, and the diameter-to-thickness ratio of the hexagonal boron nitride nanosheets is 10-50:1.

[0007] Preferably, the zwitterionic polymer graft layer is grafted onto the surface of the polydopamine transition layer via free radical polymerization, and the polydopamine transition layer serves as the interface for the free radical grafting reaction.

[0008] Preferably, the zwitterionic polymer graft layer is formed by polymerization of unsaturated monomers containing sulfonic acid groups and quaternary ammonium groups.

[0009] Preferably, the hexagonal boron nitride nanosheets are dispersed and fixed in the modified polyester fibers of the inner thermally conductive layer after surface coupling modification treatment.

[0010] Preferably, the mass ratio of the water-soluble polymer pore-forming component to the modified polyester fiber material forming the intermediate moisture-conducting layer is (5-40):100.

[0011] A second objective of this invention is to provide a method for preparing the aforementioned polyester fabric, comprising the following steps: Preparation of S1 composite spinning melt: Core layer spinning melt, intermediate layer spinning melt and skin layer spinning melt were prepared respectively; The core spinning melt includes polyester chips and hexagonal boron nitride nanosheets. The hexagonal boron nitride nanosheets are mixed with molten polyester after coupling modification and dispersion treatment to form a thermally conductive composite melt containing hexagonal boron nitride nanosheets. The intermediate layer spinning melt includes polyester chips and water-soluble polymer pore-forming components, which are melt-blended to form a composite spinning melt containing water-soluble polymer pore-forming components. The skin spinning melt is a polyester chip melt; S2 Three-layer Composite Spinning: The core layer spinning melt, the intermediate layer spinning melt, and the sheath layer spinning melt are respectively fed into a composite spinning assembly, and a composite polyester fiber with a radially distributed structure of sheath layer, intermediate layer, and core layer is obtained by radial three-layer composite spinning. S3 pore structure construction: The composite polyester fiber is placed in a water washing medium for treatment, so that the water-soluble polymer pore-forming component is dissolved and removed by water washing, forming a continuous pore structure inside the composite polyester fiber, and obtaining a polyester fiber precursor with a capillary moisture-wicking layer. S4 Surface Hydrophilic Modification: The polyester fiber precursor is placed in a reaction system containing dopamine, and dopamine is oxidatively polymerized on the fiber surface to form a polydopamine transition layer; then zwitterionic unsaturated monomers are added, and under the action of an initiator, the zwitterionic unsaturated monomers undergo free radical polymerization and are grafted onto the surface of the polydopamine transition layer to obtain modified polyester fibers. S5 Fabric Preparation: The modified polyester fiber is woven to form a polyester fabric.

[0012] Preferably, in step S1, the coupling modification of the hexagonal boron nitride nanosheets is carried out by dispersing the hexagonal boron nitride nanosheets and the silane coupling agent in an organic solvent to perform a surface coupling reaction, wherein the mass ratio of the silane coupling agent to the hexagonal boron nitride nanosheets is (0.05~0.5):1.

[0013] Preferably, in step S1, the dispersion treatment of the hexagonal boron nitride nanosheets involves premixing the coupling-modified hexagonal boron nitride nanosheets with polyester chips to form a thermally conductive masterbatch, and then melt-blending the thermally conductive masterbatch with the polyester chips to form a core layer spinning melt.

[0014] Preferably, in step S2, during the radial three-layer composite spinning process, the mass flow ratio of the skin layer spinning melt, the middle layer spinning melt, and the core layer spinning melt is 10-30:20-50:30-70.

[0015] Preferably, in step S4, the polydopamine transition layer is formed by immersing the polyester fiber precursor in an alkaline buffer solution containing dopamine for in-situ oxidative polymerization, so that dopamine is deposited on the surface of the polyester fiber; the concentration of dopamine in the alkaline buffer solution containing dopamine is 0.5-5.0 g / L.

[0016] This invention designs a radial functional gradient structure for polyester fibers, resulting in a polyester fabric that simultaneously possesses rapid moisture absorption, directional moisture conduction, rapid drying, and a cool-to-the-touch property. Unlike traditional polyester fibers that primarily rely on fiber cross-sectional irregularities or surface hydrophilic finishing to achieve moisture absorption, this invention constructs an outer hydrophilic layer, a middle moisture-conducting layer, and an inner thermally conductive layer, distributed sequentially from the outside to the inside. Through the synergistic effect between different functional regions, the coupling and regulation of moisture transfer and heat diffusion processes are achieved.

[0017] Specifically, the outer hydrophilic layer is formed on the surface of the polyester fiber and consists of a polydopamine transition layer and a zwitterionic polymer graft layer grafted onto its surface. Polydopamine has strong surface adhesion capabilities, enabling it to form a stable intermediate bonding interface on the polyester fiber surface and improving the bonding stability between subsequent hydrophilic polymer segments and the polyester fiber. By further grafting zwitterionic polymers containing sulfonic acid and quaternary ammonium groups onto the surface of the polydopamine transition layer, a large number of hydrophilic ionic groups and water-binding sites are introduced onto the fiber surface, reducing the contact angle between water droplets and the fiber surface and increasing the wetting rate of sweat or moisture on the fiber surface. Simultaneously, the zwitterionic polymer segments have strong hydration capabilities, forming a stable hydration layer on the fiber surface, which facilitates the rapid entry of moisture from the fiber exterior into the fiber interior and improves the hydrophilic stability of the fabric during long-term use.

[0018] The intermediate moisture-conducting layer is formed by introducing water-soluble polymer pore-forming components during the composite spinning process and removing them through subsequent washing to create a continuous pore structure. This multi-level pore structure, located between the outer hydrophilic layer and the inner thermally conductive layer, serves as a channel for moisture migration. When external moisture enters the fiber, it diffuses along the continuous pores into the fiber interior and along the fiber axis, driven by the wetting effect of the hydrophilic layer and the capillary action of the pores, preventing moisture from accumulating on the fiber surface for extended periods. Simultaneously, the pore structure increases the effective specific surface area within the fiber, enhancing the exchange area between moisture and air, which is beneficial for subsequent evaporation and thus improves the fabric's moisture absorption and quick-drying properties.

[0019] The inner thermally conductive layer constructs a thermally conductive composite region by introducing layered hexagonal boron nitride nanosheets within the polyester fiber. The surface-coupled modified hexagonal boron nitride nanosheets enhance the interfacial bonding performance between the nanosheets and the polyester matrix, allowing the layered inorganic components to be stably dispersed within the polyester fiber. Due to the high in-plane thermal conductivity of hexagonal boron nitride, its layered structure promotes heat transfer within the fiber, enabling rapid diffusion of localized heat generated by the skin into the fiber interior and the entire fabric, reducing heat accumulation on the skin surface and thus producing an instant cooling effect. Simultaneously, the hexagonal boron nitride nanosheets dispersed within the fiber do not significantly affect the fiber surface softness, maintaining the original wearing comfort of the polyester fabric.

[0020] Furthermore, this invention employs a radial three-layer composite spinning method, enabling the outer hydrophilic layer, middle moisture-conducting layer, and inner thermally conductive layer to form a stable spatial distribution structure within a single polyester fiber. The outer layer is responsible for rapid moisture absorption, the middle layer for continuous moisture migration, and the inner layer for rapid heat transfer. Through synergistic spatial arrangement, the moisture transport path and heat diffusion path are matched. Compared to polyester fabrics with a single hydrophilic finish, simply adding thermally conductive fillers, or simply constructing a porous structure, this invention, through a combination of fiber internal structure regulation and surface chemical modification, achieves simultaneous improvement in moisture absorption and quick-drying performance as well as a cool-to-the-touch feel, while also exhibiting good structural stability and washability.

[0021] The beneficial effects of this invention are as follows: (1) The present invention improves the wetting ability and water absorption capacity of polyester fiber by constructing a polydopamine / zwitterionic polymer composite hydrophilic layer on the surface of polyester fiber, thus overcoming the problems of strong hydrophobicity and insufficient moisture absorption of traditional polyester fiber.

[0022] (2) By removing the water-soluble polymer pore-forming components, the present invention forms a continuous capillary channel structure inside the fiber, so that the absorbed water can quickly diffuse into the inside and outside of the fiber, improve the water migration efficiency, shorten the drying time of the fabric, and achieve excellent moisture absorption and quick-drying performance.

[0023] (3) The present invention introduces surface-modified hexagonal boron nitride nanosheets into the core of polyester fiber, so that the thermally conductive inorganic components are stably dispersed inside the fiber, thereby improving the overall heat diffusion capacity of the fiber and fabric and reducing the local heat accumulation on human skin, thus giving the fabric a fast cooling sensation.

[0024] (4) The present invention adopts radial three-layer composite spinning technology, which enables the hydrophilic, moisture-wicking and heat-conducting functional areas to achieve spatial separation and synergistic combination within a single fiber. Compared with the traditional surface coating finishing method, the functional components are not easy to fall off and have better wash resistance stability.

[0025] (5) This invention combines chemical grafting modification with internal composite structure construction to achieve a balance between moisture absorption and quick-drying properties and cool touch properties while maintaining the good mechanical properties, processing properties and weaving adaptability of polyester fibers. It is suitable for sportswear, outdoor clothing and functional textile fabrics. Attached Figure Description

[0026] Figure 1 The diagram shows a TEM image of the cross-section of the modified polyester fiber; where (a) is the composite modified polyester fiber of Example 1, (b) is the polyester fiber without the skin layer of Example 4, (c) is the polyester fiber without the middle moisture-conducting layer of Example 5, and (d) is the polyester fiber without the inner heat-conducting layer of Example 6.

[0027] Figure 2 The images show the EDS elemental mapping distribution of the cross-sections of modified polyester fibers; (a) is the composite modified polyester fiber of Example 1, (b) is the high-concentration boron nitride core layer polyester fiber of Example 3, (c) is the undoped boron nitride core layer polyester fiber of Example 7, and (d) is the single-component thermally conductive modified polyester fiber of Example 11; the upper left of each group of images is the SEM electronic image, the upper right is the boron (B) elemental distribution map, the lower left is the nitrogen (N) elemental distribution map, and the lower right is the carbon (C) elemental distribution map.

[0028] Figure 3 The images show a comparison of the edge morphology of the modified polyester fiber before and after grafting. (a) shows the edge of the ungrafted polyester fiber in Example 8, and (b) shows the edge of the modified polyester fiber after grafting zwitterionic polymer in Example 1. Detailed Implementation

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In the description of this invention, the term "for example" is used to mean "used as an example, illustration, or description." Any embodiment described as "for example" in this invention is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed herein.

[0032] Unless otherwise specified, the experimental methods used in the specific implementation methods are all conventional methods, and the materials and reagents used are all commercially available unless otherwise specified.

[0033] In this invention, unless otherwise specified, "%" represents a percentage by mass; the raw materials and reagents used are all commercially available products.

[0034] The polyester fiber raw material used in this invention is spinning-grade polyethylene terephthalate (PET) chips with an intrinsic viscosity of 0.67 dL / g.

[0035] The hexagonal boron nitride nanosheets A used in this invention have an average diameter of 436 nm, an average thickness of 28.6 nm, and a diameter-to-thickness ratio of 15.2:1.

[0036] The hexagonal boron nitride nanosheets B used in this invention have an average diameter of 823 nm, an average thickness of 18.7 nm, and a diameter-to-thickness ratio of 44.0:1.

[0037] The silane coupling agent used in this invention is γ-aminopropyltriethoxysilane (KH550).

[0038] The water-soluble polymer pore-forming component A used in this invention is polyethylene glycol (PEG), with an average molecular weight of 6120.

[0039] The water-soluble polymer pore-forming component B used in this invention is polyvinyl alcohol (PVA), with an average degree of polymerization of 1780 and a degree of alcoholysis of 97.6%.

[0040] The water-soluble polyester used in this invention is a sodium isophthalate-5-sulfonate modified polyester, wherein the molar content of sodium isophthalate-5-sulfonate isophthalic acid unit is 2.8%.

[0041] The zwitterionic unsaturated monomer A used in this invention is sulfobetaine methacrylate (SBMA).

[0042] The zwitterionic unsaturated monomer B used in this invention is carboxybetaine methacrylate (CBMA).

[0043] The free radical initiator used in this invention is ammonium persulfate.

[0044] The alkaline buffer system used in this invention is a tris(hydroxymethyl)aminomethane-hydrochloric acid buffer system, wherein the Tris concentration is 10.5 mmol / L.

[0045] The washing medium used in this invention is deionized water.

[0046] Example 1: Preparation of three-layer modified polyester fibers 1. Step S1: Preparation of composite spinning melt (1) Preparation of core layer spinning melt Coupling modification: 100.0 parts by weight of dried hexagonal boron nitride nanosheets A and 5.0 parts by weight of silane coupling agent KH550 were weighed and ultrasonically dispersed in 800 parts by weight of anhydrous ethanol. The mixture was refluxed at 75°C for 6 hours. After the reaction, the nanosheets were centrifuged, washed with anhydrous ethanol, and vacuum dried at 80°C to obtain surface-modified hexagonal boron nitride nanosheets A.

[0047] Masterbatch preparation and melt blending: The modified hexagonal boron nitride nanosheets A and dried spinning-grade PET chips were mixed at a mass ratio of 10:90 and melt-blended and pelletized at 275°C using a twin-screw extruder to obtain a high-concentration thermally conductive masterbatch containing 10.0 wt% boron nitride.

[0048] Melt blending: Take 10.0 parts by weight of the thermally conductive masterbatch and mix it with 90.0 parts by weight of dried pure PET chips. Then feed the mixture into a screw extruder and melt blend it at 280°C to obtain the core layer spinning melt.

[0049] (2) Preparation of intermediate layer spinning melt Weigh 5.0 parts by weight of water-soluble polymer pore-forming component A, polyethylene glycol, and 100.0 parts by weight of dried pure PET chips. After premixing evenly in a high-speed mixer, feed the mixture into a twin-screw extruder and melt-blend at 270°C–275°C to obtain an intermediate layer composite spinning melt containing water-soluble pore-forming components.

[0050] (3) Preparation of cortical spinning melt Spinning-grade pure PET chips dried to a water content of less than 50 ppm were directly fed into a single-screw extruder and heated to melt at 280°C to obtain pure polyester skin spinning melt.

[0051] 2. Step S2: Three-layer composite spinning The prepared skin layer spinning melt, intermediate layer spinning melt, and core layer spinning melt are respectively fed into the three-layer composite spinning assembly through their respective melt channels.

[0052] Adjust the speed of the gear metering pump to control the mass flow ratio of the skin layer spinning melt, the intermediate layer spinning melt, and the core layer spinning melt to 10:20:70.

[0053] The melt is extruded through a radially concentric three-layer composite spinneret to form a nascent composite fiber with a radially encapsulated structure of skin-intermediate-core layer.

[0054] After the extruded fluid is cooled and solidified by side blowing, it is hot-stretched between an 85°C preheating roller and a 130°C drawing roller (stretching ratio of 3.2 times), and then heat-set at 150°C to obtain a composite polyester fiber with a radial three-layer distribution structure.

[0055] 3. Step S3: Hole Structure Construction The above-mentioned composite polyester fiber was immersed in deionized water at 80°C for 45 minutes for continuous extraction to dissolve and remove PEG.

[0056] After dissolution, the fibers are repeatedly rinsed with deionized water until the conductivity of the washing solution no longer changes. Then, they are dried in a vacuum drying oven at 105°C for 6 hours to obtain a polyester fiber precursor with a medium moisture-conducting layer.

[0057] 4. Step S4: Surface hydrophilic modification Construction of the polydopamine (PDA) transition layer: A dopamine solution with a concentration of 0.5 g / L was prepared using a 10.5 mmol / L Tris-HCl buffer solution. The dried polyester fiber precursor was immersed in this alkaline buffer solution and subjected to in-situ oxidative deposition at 25°C for 1.5 hours. Dopamine was controlled to spontaneously polymerize in small amounts on the fiber surface to form a film. After washing and drying, a polydopamine transition layer was deposited on the polyester surface.

[0058] Zwitterionic polymer grafting polymerization: Zwitterionic unsaturated monomer A sulfobetaine methacrylate (SBMA) was added to the system containing the above-mentioned PDA-modified fibers to achieve a monomer concentration of 0.15 mol / L. Subsequently, ammonium persulfate (concentration of 2.0 mmol / L) was added as a free radical initiator. Under nitrogen protection, the temperature was raised to 60°C for 2 hours to initiate the free radical grafting polymerization of SBMA on the surface of the polydopamine transition layer.

[0059] After the reaction was completed, the fiber was removed and ultrasonically cleaned for 15 minutes in sequence with 50°C deionized water and anhydrous ethanol to remove unreacted singles and homopolymers. Finally, it was vacuum dried at 60°C for 8 hours.

[0060] 5. Structural parameter determination The modified polyester fibers were characterized by cross-section and surface micromorphology. The total thickness of the outer hydrophilic layer was approximately 52 nm. The thickness of the polydopamine transition layer was approximately 10.4 nm, and the thickness of the surface-grafted polysulfobetaine methacrylate (PSBMA) zwitterionic graft layer was approximately 41.6 nm.

[0061] Example 2: Preparation of three-layer modified polyester fibers The difference between this embodiment and Embodiment 1 lies in: changing the type of hexagonal boron nitride nanosheets, adjusting the formulation of the intermediate layer pore-forming components, and replacing the surface-grafted zwitterionic monomers. The specific differences are as follows: 1. Step S1: Differences in the preparation of composite spinning melt Core spinning melt: The hexagonal boron nitride nanosheets A in Example 1 were replaced with hexagonal boron nitride nanosheets B. The coupling modification process, thermally conductive masterbatch preparation, and melt mixing ratio were the same as in Example 1, and a core spinning melt containing 1.0 wt% hexagonal boron nitride nanosheets B was obtained.

[0062] Intermediate layer spinning melt: The water-soluble polymer pore-forming component was replaced by a compound pore-forming agent, which was a mixture of water-soluble polymer pore-forming component A (PEG, average molecular weight 6120) and water-soluble polymer pore-forming component B (PVA) in a mass ratio of 1:1, instead of the single PEG in Example 1. 5.0 parts by mass of this compound pore-forming agent were melt-blended with 100.0 parts by mass of dried pure PET chips, maintaining the mass ratio of pore-forming component to PET at 5:100.

[0063] Skin spinning melt: exactly the same as in Example 1.

[0064] 2. Steps S2–S3: Differences between three-layer composite spinning and pore structure construction The three-layer melt mass flow ratio (10:20:70) and spinning and drawing process parameters in step S2 are the same as in Example 1.

[0065] In the water washing extraction process of step S3, due to the addition of PVA component, the temperature of the deionized water washing medium was adjusted to 90°C and the extraction time was extended to 60 minutes to ensure that PEG and PVA were fully dissolved. After washing and drying, a continuous capillary channel structure was formed in the intermediate layer.

[0066] 3. Step S4: Differences in surface hydrophilic modification Construction of polydopamine transition layer: The parameters and operations were the same as in Example 1, the dopamine concentration was maintained at 0.5 g / L, and a PDA transition layer of about 10 nm was deposited.

[0067] Zwitterionic polymer grafting: Monomer A (SBMA) is replaced with zwitterionic unsaturated monomer B carboxybetaine methacrylate (CBMA). The monomer concentration in the system is maintained at 0.15 mol / L. The reaction is carried out at 60°C for 2 hours under the action of ammonium persulfate initiator. Free radical grafting polymerization is carried out on the surface of PDA transition layer to form polycarboxybetaine methacrylate grafting layer.

[0068] 4. Structural parameter determination The total thickness of the outer hydrophilic layer of the obtained modified polyester fiber is about 51 nm, of which the thickness of the PDA transition layer is about 10.2 nm and the thickness of the PCBMA zwitterionic graft layer is about 40.8 nm.

[0069] Example 3: Preparation of three-layer modified polyester fibers The difference between this embodiment and Embodiment 1 lies in: increasing the amount of boron nitride added to the core layer and the ratio of the coupling agent, adjusting the feed ratio of the pore-forming components, changing the melt flow ratio of the three-layer spinning, and controlling the surface hydrophilic modification parameters to construct a high-thickness outer hydrophilic layer. The specific differences are as follows: 1. Step S1: Differences in the preparation of composite spinning melt Core layer spinning melt: In the coupling modification, the mass ratio of silane coupling agent KH550 to hexagonal boron nitride nanosheets A was increased to 0.5:1 (100.0 parts by mass of nanosheets A and 50.0 parts by mass of KH550 were weighed).

[0070] During the preparation and blending of thermally conductive masterbatch, the proportion of masterbatch feed is increased so that the final mass ratio of hexagonal boron nitride nanosheets A in the core polyester layer is controlled to be 10.0%.

[0071] Intermediate layer spinning melt: The pore-forming component is still the water-soluble polymer pore-forming component A (PEG0), and the mass ratio of PEG to the modified polyester material forming the intermediate moisture-conducting layer is adjusted to 40:100.

[0072] Skin spinning melt: exactly the same as in Example 1.

[0073] 2. Step S2: Differences in three-layer composite spinning Adjust the speed of the gear metering pump to set the mass flow rate ratio of the skin layer spinning melt, the intermediate layer spinning melt, and the core layer spinning melt to 30:50:30. The spinning, stretching, and heat setting process parameters are the same as in Example 1.

[0074] 3. Step S3: Differences in Hole Structure Construction The water washing, extraction and drying process is the same as in Example 1, forming a continuous capillary structure in situ in the intermediate layer.

[0075] 4. Step S4: Differences in surface hydrophilic modification Construction of polydopamine (PDA) transition layer: The concentration of dopamine in the alkaline buffer solution containing dopamine was increased to 5.0 g / L, and the impregnation reaction time was extended to 4 hours.

[0076] Zwitterionic polymer grafting layer polymerization: The concentration of monomer A (SBMA) was adjusted to 0.30 mol / L, and the free radical polymerization reaction time initiated by the initiator was controlled to 1.5 hours.

[0077] 5. Structural parameter determination The total thickness of the outer hydrophilic layer of the obtained modified polyester fiber is approximately 493 nm. Among them, the thickness of the zwitterionic polymer graft layer accounts for approximately 149.4 nm of the total thickness of the outer hydrophilic layer, and the thickness of the PDA transition layer is approximately 343.6 nm.

[0078] Example 4: Preparation of two-layer composite polyester fibers lacking a cortex The difference between this embodiment and Embodiment 1 is that the preparation of the skin layer spinning melt in step S1 is omitted, and a two-layer composite spinning process is adopted. The specific differences are as follows: Steps S1 and S2: Only the intermediate layer spinning melt (containing PEG pore-forming agent) and the core layer spinning melt (containing 1.0 wt% hexagonal boron nitride nanosheets A) are prepared. In step S2, a two-layer composite spinneret is used, and the mass flow rate ratio of the intermediate layer to the core layer melt is adjusted to 30:70 to obtain a two-layer composite polyester fiber containing only the intermediate layer and the core layer.

[0079] Steps S3 and S4: Same as in Example 1. Step S3: Wash with water to remove PEG and construct a porous structure; Step S4: Deposit a PDA transition layer directly on the exposed porous structure surface of the intermediate layer and graft zwitterionic polymer (SBMA) onto it with free radicals.

[0080] Example 5: Preparation of two-layer composite polyester fiber lacking a moisture-wicking layer The difference between this embodiment and Embodiment 1 is that the preparation of the intermediate layer spinning melt in step S1 is omitted, and the internal capillary channel structure is not constructed. The specific differences are as follows: Steps S1 and S2: Only pure PET sheath spinning melt and core layer spinning melt containing 1.0 wt% hexagonal boron nitride nanosheets A are prepared. In step S2, the mass flow ratio of the sheath to the core layer melt in the two-layer composite spinning is controlled at 20:80 to obtain a non-porous composite polyester fiber with a sheath-core structure.

[0081] Steps S3 and S4: Since there are no pore-forming components, the water washing and pore-forming step in step S3 is skipped, and the fiber is directly subjected to surface PDA deposition and zwitterionic polymer grafting modification in step S4 to obtain modified polyester fiber without a middle moisture-conducting layer.

[0082] Example 6: Preparation of a two-layer composite polyester fiber lacking an inner thermally conductive layer The difference between this embodiment and Embodiment 1 is that the core layer spinning melt is eliminated, and hexagonal boron nitride thermally conductive components and the core layer structure are not introduced into the fiber. The specific differences are as follows: Steps S1 and S2: Prepare only pure PET sheath spinning melt and intermediate layer spinning melt (containing PEG pore-forming agent). In step S2, a two-layer composite spinneret (outer sheath / inner intermediate layer) is used, and the mass flow ratio of the sheath to the intermediate layer melt is adjusted to 30:70 to obtain two-layer polyester fibers containing only the sheath and intermediate layer.

[0083] Steps S3 and S4: The process is exactly the same as in Example 1.

[0084] Example 7 Preparation of three-layer composite polyester fiber with core layer undoped with boron nitride The difference between this embodiment and Embodiment 1 is that the core layer does not contain hexagonal boron nitride nanosheets A; only pure polyester chip melt is used. The specific differences are as follows: Step S1: The core layer spinning melt and the sheath layer spinning melt were directly obtained by melting dried pure PET chips; the intermediate layer spinning melt was the same as in Example 1 (containing PEG pore-forming agent).

[0085] Steps S2–S4: The three-layer melt flow ratio (10:20:70), composite spinning, water washing extraction pore-forming, and surface PDA / zwitterion grafting processes are exactly the same as in Example 1.

[0086] Example 8: Preparation of three-layer composite polyester fibers without surface hydrophilic grafting modification The difference between this embodiment and Embodiment 1 is that the surface chemical hydrophilic modification in step S4 is not performed. The specific differences are as follows: Steps S1–S3: Following Example 1, the preparation of the three-layer composite spinning melt, the three-layer composite spinning with a flow ratio of 10:20:70, and the water washing and pore-forming process in step S3 are completed to obtain a polyester fiber precursor with an internal capillary moisture-wicking layer and a boron nitride thermally conductive core layer.

[0087] Step S4: Step S4 is omitted directly. PDA transition layer deposition and free radical grafting polymerization of zwitterionic monomer (SBMA) are not performed. The dried fiber precursor is used directly as a control sample.

[0088] Example 9 Preparation of pure sheath melt spinning and surface-modified polyester fibers The difference between this embodiment and Embodiment 1 is that only pure PET skin melt is used for single-pore spinning, and surface hydrophilic modification is performed. The specific differences are as follows: Steps S1 and S2: Only the dried pure PET chips are melted and then spun, stretched, and heat-set using a single-hole spinneret to produce ordinary solid polyester fibers.

[0089] Steps S3 and S4: Step S3, water washing and pore-forming, is omitted; the solid polyester fiber is subjected to surface PDA transition layer deposition and zwitterionic graft polymerization according to step S4.

[0090] Example 10 Preparation of polyester fibers with only intermediate layer melt spinning and pore formation The difference between this embodiment and Embodiment 1 is that only a pore-forming intermediate layer melt containing a pore-forming agent is used for single-component spinning and water washing for pore formation. The specific differences are as follows: Steps S1 and S2: PEG pore-forming agent and pure PET chips are blended and melted at a ratio of 5:100, and then spun into fibers using a single-component method.

[0091] Steps S3 and S4: Following step S3, PEG is extracted and removed from deionized water at 80°C to obtain polyester fibers with micropores distributed throughout the cross-section; the surface grafting modification in step S4 is omitted.

[0092] Example 11 Preparation of polyester fibers spun from a core-layer thermally conductive melt. The difference between this embodiment and Embodiment 1 is that only a core layer melt containing 1.0 wt% hexagonal boron nitride nanosheets A is used for single-component spinning. The specific differences are as follows: Steps S1 and S2: The polyester melt containing 1.0 wt% hexagonal boron nitride nanosheets A is directly subjected to single-component spinning and stretching heat setting to obtain solid polyester fibers with boron nitride nanosheets uniformly dispersed throughout the cross-section.

[0093] Steps S3 and S4: Steps S3 and S4 are omitted, and water washing extraction and surface grafting treatment are not performed.

[0094] Example 12 Preparation of unmodified blank control polyester fibers This example serves as a completely blank control group, and the specific steps are as follows: Spinning-grade pure PET chips (intrinsic viscosity 0.67 dL / g) dried to a water content of less than 50 ppm were fed into a single-screw extruder and melted at 280°C.

[0095] Conventional solid polyester fibers, without any chemical modification and blended with internal pores and thermally conductive fillers, are produced by extrusion through a conventional single-hole spinneret, side-blowing cooling and curing, followed by 3.2 times hot stretching and 150°C heat setting between an 85°C preheating roller and a 130°C drawing roller.

[0096] Ultrathin sections of Examples 1, 4, 5, and 6 were analyzed using transmission electron microscopy (TEM). Figure 1 As shown; (a) is the composite modified polyester fiber of Example 1, (b) is the polyester fiber without the skin layer of Example 4, (c) is the polyester fiber without the middle moisture-conducting layer of Example 5, and (d) is the polyester fiber without the inner heat-conducting layer of Example 6.

[0097] EDS boron / nitrogen element mapping in Examples 1, 3, 7, and 11 is as follows: Figure 2 As shown; (a) is the composite modified polyester fiber of Example 1, (b) is the high-concentration boron nitride core layer polyester fiber of Example 3, (c) is the undoped boron nitride core layer polyester fiber of Example 7, and (d) is the single-component thermally conductive modified polyester fiber of Example 11; the upper left of each group of images is the SEM electronic image, the upper right is the boron (B) element distribution map, the lower left is the nitrogen (N) element distribution map, and the lower right is the carbon (C) element distribution map.

[0098] Example 8.1: FE-SEM edge morphology comparison Figure 3As shown in Figure (a), the edge of the ungrafted modified polyester fiber in Example 8 is shown in Figure (b), and the edge of the modified polyester fiber after surface grafting with zwitterionic polymer in Example 1 is shown in Figure (b).

[0099] Test Example 1: Single Fiber and Fabric Performance Testing The intrinsic properties of single fibers and the macroscopic functions of fabrics were tested on the three-layer modified polyester fibers / fabrics prepared in Examples 1–3 and the comparative samples prepared in Examples 4–12.

[0100] 1. Testing Method (1) Single fiber stage test Single fiber contact angle: The advancing contact angle of a single fiber is measured using a single fiber contact angle measuring instrument (Williammi method) with deionized water as the wetting liquid.

[0101] Single fiber thermal conductivity: The axial thermal conductivity (W / m·K) of a single fiber was determined using the micro-nano scale thermal wave method (FDTR).

[0102] Breaking strength: The breaking strength (cN / dtex) was determined using a single-fiber electronic tensile tester, in accordance with GB / T14337 "Test Method for Tensile Properties of Chemical Fibers (Short Fibers)".

[0103] (2) Fabric stage testing Instant cooling performance upon contact (Q) max ): The fibers of each example / comparative example were prepared according to the same specifications (plain weave, 150 μm 5 g / m²). 2 The fabric is woven and the instantaneous cooling coefficient Q is determined according to GB / T 35263-2017 "Test and Evaluation of Instantaneous Cooling Performance of Textiles". max [J / (cm 2 ·s)).

[0104] Water droplet diffusion time and liquid water transfer performance: Referring to GB / T 21655.2-2019 "Evaluation of moisture absorption and quick-drying properties of textiles - Part 2: Dynamic moisture transfer method" (MMT), the water droplet diffusion time (s) and one-way transfer index (R) were determined. Simultaneously, referring to GB / T8629, the Q of the fabric after 50 standard washes was tested. max Retention rate.

[0105] 2. Test Results The test data for single fibers and fabrics in Examples 1–3 and Comparative Examples 4–12 are shown in Tables 1 and 2 below: Table 1 ; Table 2 ; According to the data in Tables 1 and 2, the modified polyester fiber of this invention achieves synergistic regulation of heat conduction and liquid transport through a radial three-layer structure design of "outer hydrophilic - middle moisture-conducting - inner thermally conductive". The outer hydrophilic layer is modified by grafting a polydopamine transition layer with zwitterionic polymers, which significantly improves the wettability of the polyester surface, reduces the water droplet diffusion time, and ensures interfacial stability through covalent bonding; the middle moisture-conducting layer utilizes the in-situ dissolution of water-soluble polymers to construct continuous capillary channels, and uses the capillary pressure difference of the channels to drive the liquid to migrate into the fiber interior and axially, which significantly improves the unidirectional moisture-conducting performance; the inner thermally conductive layer introduces coupled modified hexagonal boron nitride nanosheets and forms an oriented structure during spinning and stretching, establishing an axial heat conduction channel, which improves the intrinsic thermal conductivity of the fiber and the instantaneous cooling sensation upon contact with the fabric. Comparative analysis shows that the absence of any functional layer will lead to a significant decrease in the corresponding performance, making it difficult to achieve the superposition of high moisture conductivity and high thermal conductivity. At the same time, the composite structure design that confines pore formation and filler to specific layer domains reduces the damage of modified components to the mechanical properties of the polyester matrix, so that the fiber can maintain the breaking strength that meets the requirements of textile processing while possessing multifunctional properties.

[0106] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

Claims

1. A polyester fabric with moisture-wicking, quick-drying, and cool-to-the-touch properties, characterized in that, The polyester fabric is formed from modified polyester fibers, which in turn include an outer hydrophilic layer, a middle moisture-conducting layer, and an inner thermally conductive layer in the radial direction. The outer hydrophilic layer is formed on the surface of the polyester fiber and includes a polydopamine transition layer and a zwitterionic polymer graft layer formed on the surface of the polydopamine transition layer; the thickness of the outer hydrophilic layer is 50-500 nm, wherein the thickness of the zwitterionic polymer graft layer accounts for 30%-80% of the total thickness of the outer hydrophilic layer; The middle moisture-conducting layer is located between the outer hydrophilic layer and the inner thermally conductive layer, and is composed of a continuous pore structure formed inside the modified polyester fiber; the pores are formed by removing water-soluble polymer pore-forming components dispersed in the modified polyester fiber after washing and dissolving, and the average pore size of the pores is 50nm-5μm. The inner thermal conductive layer comprises modified polyester fibers and sheet-like hexagonal boron nitride nanosheets dispersed and fixed in the polyester fibers. The mass of the hexagonal boron nitride nanosheets accounts for 1%-10% of the mass of the modified polyester fibers in the inner thermal conductive layer, and the diameter-to-thickness ratio of the hexagonal boron nitride nanosheets is 10-50:

1.

2. The polyester fabric according to claim 1, characterized in that, The zwitterionic polymer graft layer is grafted onto the surface of the polydopamine transition layer via free radical polymerization, and the polydopamine transition layer serves as the interface for the free radical grafting reaction.

3. The polyester fabric according to claim 1, characterized in that, The zwitterionic polymer graft layer is formed by polymerization of unsaturated monomers containing sulfonic acid groups and quaternary ammonium groups.

4. The polyester fabric according to claim 1, characterized in that, The hexagonal boron nitride nanosheets are dispersed and fixed in the modified polyester fibers of the inner thermally conductive layer after surface coupling modification treatment.

5. The polyester fabric according to claim 1, characterized in that, The mass ratio of the water-soluble polymer pore-forming component to the modified polyester fiber material forming the intermediate moisture-conducting layer is (5-40):

100.

6. The method for preparing the polyester fabric according to any one of claims 1-5, characterized in that, Includes the following steps: Preparation of S1 composite spinning melt: Core layer spinning melt, intermediate layer spinning melt and skin layer spinning melt were prepared respectively; The core spinning melt includes polyester chips and hexagonal boron nitride nanosheets. The hexagonal boron nitride nanosheets are mixed with molten polyester after coupling modification and dispersion treatment to form a thermally conductive composite melt containing hexagonal boron nitride nanosheets. The intermediate layer spinning melt includes polyester chips and water-soluble polymer pore-forming components, which are melt-blended to form a composite spinning melt containing water-soluble polymer pore-forming components. The skin spinning melt is a polyester chip melt; S2 Three-layer Composite Spinning: The core layer spinning melt, the intermediate layer spinning melt, and the sheath layer spinning melt are respectively fed into a composite spinning assembly, and a composite polyester fiber with a radially distributed structure of sheath layer, intermediate layer, and core layer is obtained by radial three-layer composite spinning. S3 pore structure construction: The composite polyester fiber is placed in a water washing medium for treatment, so that the water-soluble polymer pore-forming component is dissolved and removed by water washing, forming a continuous pore structure inside the composite polyester fiber, and obtaining a polyester fiber precursor with a capillary moisture-wicking layer. S4 Surface Hydrophilic Modification: The polyester fiber precursor is placed in a reaction system containing dopamine, and dopamine is oxidatively polymerized on the fiber surface to form a polydopamine transition layer; then zwitterionic unsaturated monomers are added, and under the action of an initiator, the zwitterionic unsaturated monomers undergo free radical polymerization and are grafted onto the surface of the polydopamine transition layer to obtain modified polyester fibers. S5 Fabric Preparation: The modified polyester fiber is woven to form a polyester fabric.

7. The method for preparing polyester fabric according to claim 6, characterized in that, In step S1, the coupling modification of the hexagonal boron nitride nanosheets involves dispersing the hexagonal boron nitride nanosheets and a silane coupling agent in an organic solvent to carry out a surface coupling reaction, wherein the mass ratio of the silane coupling agent to the hexagonal boron nitride nanosheets is (0.05~0.5):

1.

8. The method for preparing polyester fabric according to claim 6, characterized in that, In step S1, the dispersion treatment of the hexagonal boron nitride nanosheets involves premixing the coupling-modified hexagonal boron nitride nanosheets with polyester chips to form a thermally conductive masterbatch, and then melt-blending the thermally conductive masterbatch with the polyester chips to form a core layer spinning melt.

9. The method for preparing polyester fabric according to claim 6, characterized in that, In step S2, during the radial three-layer composite spinning process, the mass flow ratio of the skin layer spinning melt, the middle layer spinning melt, and the core layer spinning melt is 10-30:20-50:30-70.

10. The method for preparing polyester fabric according to claim 6, characterized in that, In step S4, the polydopamine transition layer is formed by immersing the polyester fiber precursor in an alkaline buffer solution containing dopamine for in-situ oxidative polymerization, thereby depositing dopamine on the surface of the polyester fiber; the concentration of dopamine in the alkaline buffer solution containing dopamine is 0.5-5.0 g / L.

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