Method and system for optimizing moisture wicking performance of bio-based nylon fibers

Abstract

The present application relates to the technical field of functional fiber materials, and particularly relates to a method for optimizing the moisture absorption and sweat releasing performance of a bio-based nylon fiber. The method constructs a hydrophilic non-linearly decreasing asymmetric molecular gradient structure in the radial direction of the fiber through plasma-assisted directional grafting, and the hydrogen bond network is bridged by covalent bonds to form a cascading transmission channel. A reversible phase change hydrogel nanoarray is grown in situ on the surface of the fiber, and the synergistic effect of the phase change behavior of the nanoarray and the cascading transmission channel realizes one-way moisture transfer. By calculating the matching relationship between the hydrogen bond transmission rate and the phase change response time, a performance optimization control scheme is generated. The present application realizes dynamic and precise control of the moisture absorption and sweat releasing performance of the fiber.

Description

Technical Field

[0001] This invention relates to the field of functional fiber materials technology, and in particular to a method and system for optimizing the moisture absorption and wicking properties of bio-based nylon fibers. Background Technology

[0002] Bio-based nylon fibers have garnered widespread attention in the textile industry due to their renewable and environmentally friendly raw materials. Improving their moisture-wicking properties is key to expanding their application in functional textiles. Currently, the industry employs some conventional technical approaches for modifying the moisture-wicking properties of bio-based nylon fibers.

[0003] A common approach is to modify the overall surface of the fiber, such as by chemical grafting or physical coating, to uniformly introduce hydrophilic groups or a hydrophilic coating onto the fiber surface. This method aims to reduce the water contact angle of the fiber surface and improve its initial water adsorption capacity. Another conventional approach is to develop core-sheath composite fibers, typically using bicomponent spinning technology, to give the sheath and core layers of the fiber different hydrophilic and hydrophobic properties, in order to utilize capillary effects to guide the directional transport of water.

[0004] Conventional methods have certain limitations in practical applications. While overall surface modification improves the hydrophilicity of fibers, it often leads to the uniform spread and retention of moisture on the fiber surface, making it difficult to achieve rapid and directional perspiration. Uniform hydrophilization treatment results in a lack of effective driving force gradient in the fiber's moisture absorption and release processes, causing moisture to easily accumulate in the skin contact layer, resulting in a damp feeling and discomfort. The design of core-sheath structure fibers can guide moisture migration from the hydrophobic core layer to the hydrophilic sheath to some extent, but its performance largely depends on the stability of the interface between the two materials and the pre-set simple hydrophilic-hydrophobic binary opposition. This structure's regulation of moisture transport is static and passive, making it difficult to adapt to the complex and dynamic perspiration process of the human body. When the amount of sweat is large, the hydrophilic sheath quickly becomes saturated, leading to a decrease or even failure of its moisture-wicking capacity.

[0005] Existing methods typically treat fiber moisture absorption and wicking as two relatively independent processes, or rely solely on simple material combinations. They lack a mechanism for refined, dynamic, and coordinated control of water molecule adsorption, transfer, and release processes, starting from the fundamental structure of the fiber molecular chain hydrogen bond network. The lack of intelligent structures within the fiber capable of responding to changes in external humidity and actively adjusting moisture transport paths results in the fiber's moisture absorption and wicking efficiency and adaptability failing to meet the requirements of high-end functional textiles. Summary of the Invention

[0006] This invention provides a method and system for optimizing the moisture absorption and perspiration performance of bio-based nylon fibers, which can solve the problems in the prior art.

[0007] A first aspect of the present invention provides a method for optimizing the moisture-wicking performance of bio-based nylon fibers, comprising: Based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated, a plasma-assisted directional grafting reaction was used to introduce functional groups with different hydrophilicities in different radial regions of the fiber cross-section, thereby constructing an asymmetric molecular gradient structure with nonlinear decrease in hydrophilicity from the fiber core to the surface. The hydrogen bond network between the radial layers of the asymmetric molecular gradient structure forms a cascaded transmission channel through covalent bond bridging, resulting in modified bio-based nylon fibers with radial asymmetric hydrophilic gradients. Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels, a hydrogel nanoarray with reversible phase transition properties is grown in situ on the surface of the modified bio-based nylon fiber. Through the synergistic effect of the reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels, a composite fiber structure with unidirectional moisture-wicking capability is formed. Based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase transition threshold of the hydrogel nanoarray, the optimal matching relationship between the hydrogen bond cascade transport rate and the phase transition response time of the nanoarray under different humidity loads is calculated. Combined with the unidirectional moisture-wicking capacity parameters of the composite fiber structure, an optimized control scheme for the moisture absorption and perspiration performance of the fiber is generated.

[0008] Based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated, a plasma-assisted directional grafting reaction was used to introduce functional groups with differentiated hydrophilicity into different radial regions of the fiber cross-section, constructing an asymmetric molecular gradient structure exhibiting a non-linear decrease in hydrophilicity from the fiber core to the surface, including: The spatial distribution information of amide groups and the coordination state information of hydrogen bond interaction sites in the corresponding molecular chain segments of the bio-based nylon fiber to be processed are obtained by spectral analysis technology. Based on the spatial distribution information of amide groups and the coordination state information of hydrogen bond interaction sites, a three-dimensional spatial mapping relationship of hydrogen bond network topology is constructed. Based on the density distribution gradient of hydrogen bond interaction sites in the three-dimensional spatial mapping relationship, the plasma bombardment energy distribution scheme and the radial stratification selection rule of grafting reaction active sites corresponding to different radial regions of the fiber cross section are determined. According to the plasma bombardment energy distribution scheme, the surface of the bio-based nylon fiber to be treated is subjected to regional plasma treatment to form a free radical distribution layer with different activity levels in different radial regions of the fiber cross-section. According to the radial stratification selection rule of the grafting reaction active sites, functional groups with different hydrophilic segment lengths are grafted to the active sites in the corresponding radial regions of the free radical distribution layer to construct an asymmetric molecular gradient structure with nonlinear decrease in hydrophilicity from the fiber core to the surface.

[0009] Based on the density distribution gradient of hydrogen bond interaction sites in the aforementioned three-dimensional spatial mapping relationship, the plasma bombardment energy distribution scheme and the radial stratification selection rule for grafting reaction active sites corresponding to different radial regions of the fiber cross-section are determined, including: Based on the gradient change rate of hydrogen bond density between adjacent radial regions, a monotonically decreasing correspondence between the radial region index and the plasma bombardment energy requirement is constructed, and the fiber cross-section is divided into multiple radial levels in the order from the core to the surface. In each radial level, plasma bombardment energy values ​​are allocated to each radial level according to the inverse proportional relationship between the corresponding hydrogen bond density value and the plasma bombardment energy requirement value. The plasma bombardment energy values ​​corresponding to each radial level are summarized to form the plasma bombardment energy distribution scheme corresponding to different radial regions of the fiber cross-section. Based on the coordination saturation parameters of each hydrogen bond interaction site, unsaturated hydrogen bond interaction sites in each radial region are identified as preferred active sites for the grafting reaction. The length range of the hydrophilic chain segment of the functional group that is suitable for each radial region is determined according to the distribution range of the coordination saturation parameter. The sequence of the preferred treatment site for grafting reaction in each radial region is determined according to the spatial distribution of the preferred active site. The length range of the hydrophilic chain segment of the functional group corresponding to each radial region is associated with the sequence of the preferred treatment site to form the radial stratification selection rule of the active site for grafting reaction.

[0010] The hydrogen bond network between the radial layers of the asymmetric molecular gradient structure forms a cascade transport channel through covalent bond bridging, resulting in modified bio-based nylon fibers with radial asymmetric hydrophilic gradients, including: The interface region between adjacent radial layers in the asymmetric molecular gradient structure is cross-linked to form a covalent bridge structure between the grafted functional groups between adjacent radial layers. The spatial coordinate information and covalent bond length information of the covalent bridging structure are obtained. The interface position of the covalent bridging structure in each radial layer is determined according to the spatial coordinate information. The spatial distance between the grafted functional groups of adjacent radial layers connected by each covalent bridging structure is calculated according to the covalent bond length information. The hydrogen bond interaction sites corresponding to the grafted functional groups whose spatial distance is less than a preset hydrogen bond interaction distance threshold are identified as cascade transfer nodes. Based on the spatial positional relationship of the cascaded transmission nodes in each radial layer, a hydrogen bond network cascaded transmission channel topology is constructed that runs from the fiber core to the surface layer and through each radial layer. Based on the connection density distribution of the cascaded transport nodes in the hydrogen bond network cascaded transport channel topology, the continuity and efficiency of water molecule transport between each radial layer are evaluated. The fibers corresponding to the hydrogen bond network cascaded transport channel topology that satisfy a preset continuity threshold and a preset efficiency threshold are identified as modified bio-based nylon fibers with radial asymmetric hydrophilic gradients.

[0011] Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels, a hydrogel nanoarray with reversible phase transition properties is grown in situ on the surface of the modified bio-based nylon fiber, comprising: Based on the hydrogen bond density values ​​of each radial layer, the hydrogen bond density reduction rate from the fiber core to the surface layer is calculated. The characteristic value of the hydrogen bond density of the fiber surface layer is determined according to the hydrogen bond density reduction rate and correlated with the density of hydrophilic functional groups on the fiber surface layer. The spatial location of the hydrogel monomer grafting site is then determined. Based on the topology of the cascaded transport channels, the spatial distribution density of the cascaded transport nodes from the fiber core to the fiber surface is statistically analyzed, and the water molecule transport active region on the fiber surface is determined as the growth site of the hydrogel nanounit based on the spatial distribution density. The spatial position of the hydrogel monomer grafting site is associated with the growth site, and the in-situ polymerization reaction of the hydrogel monomer is initiated at the hydrogel monomer grafting site at the growth site. By controlling the initiation density of the in-situ polymerization reaction and the degree of crosslinking of the polymer chain segments, hydrogel units with nanoscale spatial arrangement regularity are formed. Temperature-responsive and humidity-responsive molecular chain segments are introduced into the polymer network of the hydrogel unit. The reversible transition between the swelling and shrinkage states of the hydrogel unit is achieved through the synergistic response of the temperature-responsive and humidity-responsive molecular chain segments. The hydrogel units with reversible transition capabilities are assembled according to the nanoscale spatial arrangement rules to form a hydrogel nanoarray with reversible phase transition characteristics.

[0012] The reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels work together to form a composite fiber structure with unidirectional moisture-wicking capability, comprising: The water absorption response time of the hydrogel unit in the hydrogel nanoarray from the shrinking state to the swelling state and the dehydration response time from the swelling state to the shrinking state are monitored, and the phase transition time asymmetry characteristic parameter of the hydrogel nanoarray is determined based on the difference between the water absorption response time and the dehydration response time. The transfer time of water molecules from the fiber core to the fiber surface in the cascade transfer channel is extracted. The connection density distribution of the cascade transfer nodes in the cascade transfer channel is adjusted according to the time matching relationship between the transfer time and the water absorption response time, so that the water molecule transfer rate of the cascade transfer channel and the water absorption response rate of the hydrogel nanoarray are synchronized and coordinated. Based on the phase transition time asymmetry characteristic parameter, when the humidity of the external environment of the fiber is higher than that of the internal environment of the fiber, the hydrogel nanoarray maintains a swollen state to prevent external water molecules from penetrating into the fiber. When the humidity of the external environment of the fiber is lower than that of the internal environment of the fiber, the hydrogel nanoarray quickly transforms into a contracted state to release water molecules to the external environment. At the same time, based on the synchronous and synergistic maintenance of the cascaded transfer channel, water molecules inside the fiber are transferred to the surface, forming the composite fiber structure with unidirectional moisture-wicking capability.

[0013] Based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase transition threshold of the hydrogel nanoarray, the optimal matching relationship between the hydrogen bond cascade transport rate and the phase transition response time of the nanoarray under different humidity loads is calculated. Combined with the unidirectional moisture-wicking capacity parameters of the composite fiber structure, an optimized control scheme for the fiber's moisture absorption and perspiration performance is generated, including: Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure, the energy barrier distribution of water molecules between each radial layer during the dynamic equilibrium of hydrogen bond breaking and recombination is calculated, and the hydrogen bond cascade transport kinetic parameters are determined according to the energy barrier distribution. Calculate the critical environmental temperature and humidity conditions required for the hydrogel nanoarray to transition from a contracted state to a swollen state and from a swollen state to a contracted state, and determine the reversible phase transition threshold of the hydrogel nanoarray based on the critical environmental temperature and humidity conditions. The time matching coefficient between the hydrogen bond cascade transport rate inside the asymmetric molecular gradient structure and the phase transition response time of the hydrogel nanoarray surface is calculated based on the hydrogen bond cascade transport kinetic parameters and the reversible phase transition threshold under different humidity loads. The optimal matching relationship between the hydrogen bond cascade transport rate and the nanoarray phase transition response time is determined based on the time matching coefficient. By regulating the radial distribution density of hydrophilic functional groups in the asymmetric molecular gradient structure and the degree of crosslinking of polymeric segments in the hydrogel nanoarray, the hydrogen bond cascade transfer rate and the phase transition response time of the nanoarray satisfy the optimal matching relationship, thereby generating an optimized regulation scheme for the moisture absorption and perspiration performance of the fiber.

[0014] A second aspect of the present invention provides a system for optimizing the moisture-wicking performance of bio-based nylon fibers, comprising: The gradient building unit is used to construct an asymmetric molecular gradient structure that exhibits a nonlinear decrease in hydrophilicity from the fiber core to the surface by introducing functional groups with different hydrophilicities into different radial regions of the fiber cross-section through a plasma-assisted directional grafting reaction based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated. Channel forming units are used to form cascaded transport channels by connecting the hydrogen bond network between each radial layer of the asymmetric molecular gradient structure through covalent bonds, thereby obtaining modified bio-based nylon fibers with radial asymmetric hydrophilic gradients. An array growth unit is used to grow a hydrogel nanoarray with reversible phase transition properties in situ on the surface of the modified bio-based nylon fiber, based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels. Synergistic unit, used to form a composite fiber structure with unidirectional moisture-wicking capability through the synergistic effect of the reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels; The regulation scheme unit is used to calculate the optimal matching relationship between the hydrogen bond cascade transport rate and the phase change response time of the nanoarray under different humidity loads based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase change threshold of the hydrogel nanoarray, and generate an optimized regulation scheme for the moisture absorption and perspiration performance of the fiber by combining the unidirectional moisture-wicking capacity parameter of the composite fiber structure.

[0015] A third aspect of the present invention provides an electronic device, comprising: processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the aforementioned method.

[0016] A fourth aspect of the present invention provides a computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, implement the aforementioned method.

[0017] The beneficial effects of this application are as follows: This method achieves rapid, directional water transport along the radial direction by constructing an asymmetric hydrophilic gradient structure from the fiber core to the surface. The hydrogen bond network within the fiber is covalently bridged to form cascaded transport channels, significantly improving the diffusion efficiency of water within the fiber. The in-situ grown hydrogel nanoarray on the surface possesses reversible phase transition properties, enabling intelligent adjustment of surface wettability according to changes in ambient humidity. This structural design allows water to rapidly migrate from the highly hydrophilic core to the surface while simultaneously inhibiting back diffusion.

[0018] The synergistic effect of the asymmetric molecular gradient structure and the hydrogel nanoarray endows the composite fiber with excellent one-way moisture wicking capability. Cascaded transport channels ensure continuous and efficient moisture transfer within the fiber, while the phase change behavior of the nanoarray precisely regulates the surface moisture evaporation rate. This combination effectively solves the problem of stuffiness that traditional nylon fibers tend to cause after absorbing moisture, achieving a dynamic balance between moisture absorption and perspiration. The fiber maintains a dry and comfortable feel under different humidity loads.

[0019] By calculating the optimal matching relationship between the hydrogen bond cascade transport rate and the phase transition response time of the nanoarray, this method can generate targeted performance optimization and control schemes. These schemes can precisely adjust the fiber's structural parameters and response thresholds according to the humidity conditions of the specific application environment, thereby achieving active control over moisture absorption and wicking performance. This optimization strategy based on kinetic coupling significantly improves the fiber's environmental adaptability and performance stability under different usage scenarios.

[0020] The resulting composite fiber structure exhibits excellent overall performance, retaining not only the inherent advantages of bio-based nylon fibers but also achieving breakthroughs in moisture-wicking capabilities. Its one-way moisture-wicking mechanism is highly efficient and reliable, making it widely applicable in sportswear, outdoor equipment, and specialty functional textiles. This method provides a new technical pathway for the functional design of high-performance bio-based fibers, possessing significant practical value and promising prospects for wider application. Attached Figure Description

[0021] Figure 1 A flowchart illustrating the method for optimizing the moisture-wicking performance of bio-based nylon fibers; Figure 2 A schematic diagram illustrating the process of constructing a cascaded transmission channel for hydrogen bond networks. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0023] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0024] Figure 1 This is a schematic flowchart illustrating the method for optimizing the moisture-wicking performance of bio-based nylon fibers according to an embodiment of the present invention. Figure 1As shown, the methods for optimizing the moisture-wicking performance of bio-based nylon fibers include: Based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated, a plasma-assisted directional grafting reaction was used to introduce functional groups with different hydrophilicities in different radial regions of the fiber cross-section, thereby constructing an asymmetric molecular gradient structure with nonlinear decrease in hydrophilicity from the fiber core to the surface. The hydrogen bond network between the radial layers of the asymmetric molecular gradient structure forms a cascaded transmission channel through covalent bond bridging, resulting in modified bio-based nylon fibers with radial asymmetric hydrophilic gradients. Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels, a hydrogel nanoarray with reversible phase transition properties is grown in situ on the surface of the modified bio-based nylon fiber. Through the synergistic effect of the reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels, a composite fiber structure with unidirectional moisture-wicking capability is formed. Based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase transition threshold of the hydrogel nanoarray, the optimal matching relationship between the hydrogen bond cascade transport rate and the phase transition response time of the nanoarray under different humidity loads is calculated. Combined with the unidirectional moisture-wicking capacity parameters of the composite fiber structure, an optimized control scheme for the moisture absorption and perspiration performance of the fiber is generated.

[0025] In one optional implementation, based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated, a plasma-assisted directional grafting reaction is used to introduce functional groups with differentiated hydrophilicity into different radial regions of the fiber cross-section, constructing an asymmetric molecular gradient structure exhibiting a non-linear decrease in hydrophilicity from the fiber core to the surface, including: The spatial distribution information of amide groups and the coordination state information of hydrogen bond interaction sites in the corresponding molecular chain segments of the bio-based nylon fiber to be processed are obtained by spectral analysis technology. Based on the spatial distribution information of amide groups and the coordination state information of hydrogen bond interaction sites, a three-dimensional spatial mapping relationship of hydrogen bond network topology is constructed. Based on the density distribution gradient of hydrogen bond interaction sites in the three-dimensional spatial mapping relationship, the plasma bombardment energy distribution scheme and the radial stratification selection rule of grafting reaction active sites corresponding to different radial regions of the fiber cross section are determined. According to the plasma bombardment energy distribution scheme, the surface of the bio-based nylon fiber to be treated is subjected to regional plasma treatment to form a free radical distribution layer with different activity levels in different radial regions of the fiber cross-section. According to the radial stratification selection rule of the grafting reaction active sites, functional groups with different hydrophilic segment lengths are grafted to the active sites in the corresponding radial regions of the free radical distribution layer to construct an asymmetric molecular gradient structure with nonlinear decrease in hydrophilicity from the fiber core to the surface.

[0026] To investigate the spatial distribution characteristics of amide groups in the molecular chain segments of bio-based nylon fibers, Fourier transform infrared spectroscopy was used to scan and analyze the fiber cross-section. The results were obtained at a depth of 1640 cm⁻¹. -1 The amide I band at 1540 cm -1 The spatial variation of the absorption peak intensity of the amide II band at different radial positions from the core to the surface of the fiber was analyzed to obtain the concentration distribution data of amide groups. Combined with Raman spectroscopy, the fiber cross-section was scanned point-by-point at micrometer-level spatial resolution, using a 3300 cm⁻¹ spectroscopy method. -1 The nearby 7-H stretching vibration peak is at 1630 cm⁻¹ -1 The displacement of the nearby C=O stretching vibration peaks was used to identify the coordination state of hydrogen bond interaction sites, distinguishing between free amide groups and amide groups participating in the hydrogen bond network. For bio-based nylon fibers with a diameter of 15 micrometers, a detection point was set every 1 micrometer along the radial direction to obtain 15 layers of radial distribution data. Each layer of data included two parameters: amide group density and hydrogen bond coordination rate.

[0027] Based on the collected multi-layer radial distribution data, a three-dimensional spatial mapping model of the hydrogen bond network topology of the fiber cross-section was constructed using a spatial interpolation algorithm. The fiber cross-section was divided into concentric ring layers with a spacing of 0.5 micrometers. The density of hydrogen bond interaction sites within each ring layer was calculated by cubic spline interpolation of data from adjacent detection points. For the spatial distribution of hydrogen bond coordination states, a coordination saturation parameter was introduced to characterize the integrity of the hydrogen bond network at different radial positions. Coordination saturation is defined as the ratio of the number of amide groups actually participating in hydrogen bonding to the theoretical maximum number of hydrogen bonds. By analyzing the radial variation curve of coordination saturation, key radial positions where hydrogen bond density abruptly changes were identified. These positions correspond to the transition regions of molecular chain segment arrangement, typically located in two radial ranges: 30% to 40% and 60% to 70% of the fiber radius.

[0028] Based on the constructed three-dimensional spatial mapping model, the hydrogen bond interaction site density gradient in different radial regions was calculated. The fiber cross-section was divided into three main radial regions from the core to the surface: the core region, the transition region, and the surface region. The core region corresponds to the range of 0% to 40% of the fiber radius, where the hydrogen bond density is the highest, and the coordination saturation reaches over 85%. The transition region corresponds to the range of 40% to 70% of the radius, where the hydrogen bond density shows a non-linear decreasing trend. The surface region corresponds to the range of 70% to 100% of the radius, where the hydrogen bond density is relatively low but the molecular chain segment orientation is high. Differentiated plasma bombardment energy schemes were designed for the three radial regions. The core region used a higher bombardment energy to generate sufficient free radicals in the dense molecular chain structure, with an RF power of 200 W and a processing time of 90 seconds. The transition region used a medium bombardment energy, with the RF power reduced to 150 W and the processing time extended to 120 seconds to compensate for the decrease in activation efficiency caused by the reduced energy. The surface region used a lower bombardment energy, with the RF power set at 100 W and the processing time controlled at 60 seconds to avoid excessive bombardment that could damage the ordered structure of the fiber surface.

[0029] Based on the hydrogen bond density distribution characteristics, a radial stratification selection rule for grafting reaction active sites was formulated. In the high hydrogen bond density environment of the core region, regions with densely distributed amide groups were preferentially selected as active sites. These sites are surrounded by abundant hydrogen bond acceptors, which is conducive to the stable anchoring of long-chain hydrophilic functional groups. The selection of active sites in the transition region follows the principle of maximizing the hydrogen bond gradient, placing active sites at radial positions where the coordination saturation changes most drastically, so that the grafted functional groups can interact with adjacent layers of different hydrogen bond densities simultaneously. The selection of active sites in the surface region focuses on regions with high molecular chain orientation. Although these regions have lower hydrogen bond densities, the regular arrangement of molecular chains provides an ordered template for the directional grafting of short-chain functional groups.

[0030] The bio-based nylon fibers to be treated were placed in a low-temperature plasma treatment device, using argon gas as the plasma source, with the pressure controlled within the range of 10 Pa to 20 Pa. By adjusting the distance between the fiber and the plasma generator, as well as the fiber's rotation speed, regional energy input was achieved for different radial regions of the fiber cross-section. For the core region, the distance between the fiber and the generator was set to 8 cm, and the fiber rotated at a speed of 120 rpm, allowing the plasma to penetrate into the fiber interior. For the transition region, the distance was adjusted to 12 cm, and the rotation speed was reduced to 80 rpm. For the surface region, the distance was increased to 15 cm, and the rotation speed was increased to 150 rpm to ensure uniform activation of the surface layer. During plasma bombardment, the CH bonds and 7-H bonds in the molecular chain segments on the fiber surface broke, forming carbon and nitrogen free radicals. These free radicals exhibited radial stratification characteristics on the fiber cross-section corresponding to the plasma energy distribution.

[0031] Three types of functional group monomer solutions with different hydrophilic segment lengths were prepared. The first type was a long-chain hydrophilic monomer, using polyethylene glycol methacrylate with an average degree of polymerization of 15 and a hydrophilic segment length of approximately 3 nm. The second type was a medium-chain hydrophilic monomer, using hydroxyethyl methacrylate with a hydrophilic segment length of approximately 1.5 nm. The third type was a short-chain hydrophilic monomer, using acrylic acid with a hydrophilic segment length of approximately 0.5 nm. The plasma-treated fibers were rapidly transferred to a grafting reactor. First, the fibers were immersed in an 8% (w / w) solution of the long-chain hydrophilic monomer at a reaction temperature of 55°C for 45 minutes, allowing the long-chain monomer to preferentially graft onto the carbon radicals in the core region. Subsequently, the fibers were transferred to a 6% (w / w) solution of the medium-chain hydrophilic monomer, with the reaction temperature reduced to 45°C and the reaction time 30 minutes. The medium-chain monomer was then primarily grafted onto the active sites in the transition region. Finally, the fiber was placed in a 4% (w / w) solution of short-chain hydrophilic monomers, the reaction temperature was set at 35 degrees Celsius, and the reaction time was 20 minutes to complete the grafting of short-chain functional groups in the surface region.

[0032] After the grafting reaction is completed, the fibers undergo multi-stage washing to remove unreacted monomers and homopolymers. The first stage of washing uses deionized water at 60 degrees Celsius, and the water is replaced after 15 minutes of agitation. The second stage of washing is carried out at 40 degrees Celsius, and the washing time is extended to 20 minutes. The third stage of washing is carried out at room temperature for 10 minutes.

[0033] In one optional implementation, the plasma bombardment energy distribution scheme and the radial stratification selection rule for grafting reaction active sites corresponding to different radial regions of the fiber cross-section are determined based on the density distribution gradient of hydrogen bonding sites in the three-dimensional spatial mapping relationship, including: Based on the gradient change rate of hydrogen bond density between adjacent radial regions, a monotonically decreasing correspondence between the radial region index and the plasma bombardment energy requirement is constructed, and the fiber cross-section is divided into multiple radial levels in the order from the core to the surface. In each radial level, plasma bombardment energy values ​​are allocated to each radial level according to the inverse proportional relationship between the corresponding hydrogen bond density value and the plasma bombardment energy requirement value. The plasma bombardment energy values ​​corresponding to each radial level are summarized to form the plasma bombardment energy distribution scheme corresponding to different radial regions of the fiber cross-section. Based on the coordination saturation parameters of each hydrogen bond interaction site, unsaturated hydrogen bond interaction sites in each radial region are identified as preferred active sites for the grafting reaction. The length range of the hydrophilic chain segment of the functional group that is suitable for each radial region is determined according to the distribution range of the coordination saturation parameter. The sequence of the preferred treatment site for grafting reaction in each radial region is determined according to the spatial distribution of the preferred active site. The length range of the hydrophilic chain segment of the functional group corresponding to each radial region is associated with the sequence of the preferred treatment site to form the radial stratification selection rule of the active site for grafting reaction.

[0034] After obtaining the three-dimensional spatial mapping of the hydrogen bond network of the bio-based nylon fiber to be treated, it is necessary to further determine the plasma bombardment energy distribution scheme and the radial stratification selection rule of the grafting reaction active sites corresponding to different radial regions of the fiber cross-section. By quantitatively analyzing the density distribution gradient of hydrogen bond interaction sites, a correspondence between the radial region index and plasma treatment parameters can be established, providing precise energy input guidance for subsequent directional grafting reactions.

[0035] To address the radial structural characteristics of the fiber cross-section from the core to the surface, a radial region indexing system is constructed based on the gradient rate of hydrogen bond density change between adjacent radial regions. Specifically, using hydrogen bond density as a baseline parameter, the gradient rate of hydrogen bond density change is obtained by calculating the ratio of the difference in hydrogen bond density between any two adjacent radial positions to the radial distance. When this gradient rate of change exceeds a preset threshold, a region boundary point is set at the corresponding radial position. Based on these boundary points, the entire fiber cross-section is sequentially divided into multiple radial levels from the core to the surface, with each radial level assigned an index number, the core region having the smallest index value and the surface region having the largest index value. This division method ensures that the hydrogen bond density within each radial level is relatively uniform, while significant differences in hydrogen bond density exist between different levels.

[0036] After completing the radial hierarchical division, a monotonically decreasing correspondence was established between the radial region index and the plasma bombardment energy requirement. Because the core region has a higher hydrogen bond density and more tightly packed molecular chains, a higher plasma bombardment energy is required to effectively activate the active sites of the molecular chains; while the surface region has a relatively lower hydrogen bond density and more loosely packed molecular chains, allowing for activation of active sites with a lower plasma bombardment energy. Therefore, an inverse correspondence was established between the index values ​​of each radial level and the plasma bombardment energy requirement: the smaller the index value, the higher the energy requirement; and the larger the index value, the lower the energy requirement. This monotonically decreasing correspondence ensures that the plasma treatment process can adapt to the structural characteristics of different radial regions.

[0037] Within each radial level, a specific plasma bombardment energy value is assigned based on the inverse relationship between the corresponding hydrogen bond density and the plasma bombardment energy requirement. The hydrogen bond density of a given radial level is set as ρ. H Introducing the energy distribution coefficient kE The plasma bombardment energy value E corresponding to this radial level plasma E plasma =k E / ρ H Estimation is performed. Energy distribution coefficient k E The plasma bombardment energy was calibrated based on the material properties and target modification effects of the bio-based nylon fiber. For the core region with high hydrogen bond density, the calculated plasma bombardment energy values ​​typically range from 150 watts to 250 watts; for the intermediate layer region with moderate hydrogen bond density, the plasma bombardment energy values ​​typically range from 80 watts to 150 watts; and for the surface region with low hydrogen bond density, the plasma bombardment energy values ​​typically range from 30 watts to 80 watts. The plasma bombardment energy values ​​corresponding to each radial level were arranged in radial order to form a complete plasma bombardment energy distribution scheme. This scheme clarifies the plasma treatment energy parameters that should be accepted by each radial region from the fiber core to the surface.

[0038] Based on the determined plasma bombardment energy distribution scheme, a radial stratification selection rule for grafting reaction active sites is further established. According to the coordination saturation parameter of each hydrogen bonding interaction site, unsaturated hydrogen bonding interaction sites in each radial region are identified as preferential active sites for the grafting reaction. The coordination saturation parameter characterizes the ratio of the number of hydrogen bonds already formed around the hydrogen bonding interaction site to the theoretical maximum number of hydrogen bonds. When the coordination saturation of a hydrogen bonding interaction site is below 0.7, the site is considered to have unsaturated hydrogen bond coordination ability and possess the spatial conditions and reactivity for grafting functional groups. By traversing all hydrogen bonding interaction sites in each radial region, sites with coordination saturation below a threshold are screened and marked as preferential active sites for the grafting reaction. These preferential active sites, after activation by plasma bombardment, can undergo efficient covalent grafting reactions with functional groups.

[0039] Based on the distribution range of coordination saturation parameters, the suitable hydrophilic segment length range of functional groups for each radial region is determined. Regions with lower coordination saturation have a larger space margin around hydrogen bond interaction sites, making them suitable for grafting functional groups with longer hydrophilic segments to fully utilize available space and enhance local hydrophilicity. Regions with higher coordination saturation have limited space around hydrogen bond interaction sites, making them suitable for grafting functional groups with shorter hydrophilic segments to avoid decreased grafting efficiency due to steric hindrance. For the core region, the coordination saturation is typically in the range of 0.3 to 0.5, and the suitable hydrophilic segment length range of functional groups is 15 to 25 repeating units. For the intermediate layer region, the coordination saturation is typically in the range of 0.5 to 0.7, and the suitable hydrophilic segment length range of functional groups is 8 to 15 repeating units. For the surface region, the coordination saturation is typically in the range of 0.7 to 0.85, and the suitable hydrophilic segment length range of functional groups is 3 to 8 repeating units.

[0040] Based on the spatial distribution of preferred active sites, the preferred treatment site sequences for grafting reactions in each radial region are determined. Within the same radial region, the spatial distribution of preferred active sites exhibits characteristics of local aggregation or dispersion. Active sites with relatively uniform spatial distribution are preferentially selected for grafting treatment to avoid aggregation effects caused by excessively high local functional group densities. By calculating the average distance between each preferred active site and its nearest neighbor, active sites with moderate average distances are preferentially included in the treatment sequence. Simultaneously, considering the coordination saturation values ​​of each preferred active site, active sites with lower coordination saturation are preferentially treated to maximize the efficiency of the grafting reaction. The length range of the hydrophilic segment of the functional group corresponding to each radial region is correlated with the preferred treatment site sequence to form a radial stratification selection rule for grafting reaction active sites.

[0041] In one optional embodiment, the hydrogen bond network between the radial layers of the asymmetric molecular gradient structure forms a cascaded transport channel through covalent bond bridging, resulting in modified bio-based nylon fibers with radial asymmetric hydrophilic gradients, comprising: The interface region between adjacent radial layers in the asymmetric molecular gradient structure is cross-linked to form a covalent bridge structure between the grafted functional groups between adjacent radial layers. The spatial coordinate information and covalent bond length information of the covalent bridging structure are obtained. The interface position of the covalent bridging structure in each radial layer is determined according to the spatial coordinate information. The spatial distance between the grafted functional groups of adjacent radial layers connected by each covalent bridging structure is calculated according to the covalent bond length information. The hydrogen bond interaction sites corresponding to the grafted functional groups whose spatial distance is less than a preset hydrogen bond interaction distance threshold are identified as cascade transfer nodes. Based on the spatial positional relationship of the cascaded transmission nodes in each radial layer, a hydrogen bond network cascaded transmission channel topology is constructed that runs from the fiber core to the surface layer and through each radial layer. Based on the connection density distribution of the cascaded transport nodes in the hydrogen bond network cascaded transport channel topology, the continuity and efficiency of water molecule transport between each radial layer are evaluated. The fibers corresponding to the hydrogen bond network cascaded transport channel topology that satisfy a preset continuity threshold and a preset efficiency threshold are identified as modified bio-based nylon fibers with radial asymmetric hydrophilic gradients.

[0042] like Figure 2 As shown, the method includes: After constructing the asymmetric molecular gradient structure through plasma-assisted directional grafting, cross-linking treatment is required at the interface regions of adjacent radial layers to form stable covalent bridge structures between the functional groups grafted onto different radial layers. The cross-linking treatment employs UV-initiated free radical cross-linking. The grafted bio-based nylon fibers are placed in a solution containing a bifunctional cross-linking agent. The selection of the cross-linking agent must be matched based on the chemical properties of the functional groups in different radial layers. Between the hydroxyethyl acrylamide groups grafted into the core region and the hydroxypropyl methacrylamide groups grafted into the transition region, a cross-linking agent containing a diacrylate structure is used. Free radical polymerization is initiated under UV irradiation at a wavelength of 365 nm. The acrylate groups at both ends of the diacrylate molecule undergo addition reactions with the acrylamide groups of the adjacent radial layers, forming covalent bridge structures with carbon-carbon single bonds. The cross-linking treatment between the transition region and the surface region uses a bifunctional cross-linking agent containing isocyanate groups. The isocyanate groups can react with hydroxyl groups to form urethane bonds, achieving covalent connections between different hydrophilic functional groups. The crosslinking reaction time is controlled between 15 and 25 minutes, and the concentration of the crosslinking agent is adjusted according to the grafting density to ensure that a uniformly distributed covalent bond bridging structure is formed in the interface region of adjacent radial layers.

[0043] Spatial coordinate information of covalently bridged structures was obtained using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. Cross-linked fiber samples were subjected to liquid nitrogen brittle fracture treatment to obtain fresh cross-sections. The microstructure of the fiber cross-section was observed under scanning electron microscopy at magnifications of 5000x to 10000x, and the interface boundaries of different radial layers were identified using backscattered electron imaging mode. Energy-dispersive X-ray spectroscopy point scanning analysis was performed on the interface regions, and the positions of the covalently bridged structures were determined based on the distribution of characteristic elements. A cylindrical coordinate system with the fiber center as the origin was established, and the radial coordinate r, circumferential angle θ, and axial position z of each covalently bridged structure were recorded. Covalent bond length information was obtained using a combination of Fourier transform infrared spectroscopy and Raman spectroscopy. In the infrared spectrum, the absorption peaks in the wavenumber range of 1720 to 1740 correspond to the carbonyl stretching vibrations of ester bonds, and the absorption peaks in the wavenumber range of 1530 to 1550 correspond to the characteristic peaks of the amide second band of urethane bonds. The changes in covalent bond lengths were estimated by the shifts in peak positions. The characteristic peaks in the Raman spectrum in the wavenumber range of 850 to 900 correspond to the stretching vibrations of carbon-carbon single bonds. By combining quantum chemical calculation methods, the spectral characteristic parameters are converted into actual covalent bond length values.

[0044] Based on the spatial coordinates of the covalently bridged structures, the interface locations of covalently bridged structures in each radial layer are marked in the digital model of the fiber cross-section. The fiber cross-section is divided into several concentric rings, each ring corresponding to a radial layer, and the annular region between adjacent rings is the interface region. The number and spatial distribution of covalently bridged structures in each interface region are counted, and the circumferential distribution uniformity parameter of the interface locations is calculated. For each covalently bridged structure, the Euclidean distance d between the two grafted functional groups connected to it is calculated based on the spatial coordinates of the two grafted functional groups in their respective radial layers. Hydrogen bonding typically occurs within a distance of less than 0.35 nm, therefore, a preset hydrogen bonding distance threshold is set to 0.35 nm. When the calculated spatial distance d is less than this threshold, it indicates the possibility of hydrogen bonding between the two grafted functional groups connected by the covalently bridged structure, and the hydrogen bonding sites corresponding to these two functional groups are identified as cascade transfer nodes. Hydrogen bonding sites include proton donor sites in the functional groups, such as hydrogen atoms in hydroxyl groups, and proton acceptor sites, such as oxygen atoms in carbonyl groups or nitrogen atoms in amino groups.

[0045] The spatial relationships of cascaded transmission nodes in each radial layer are described by constructing a three-dimensional topological network model. Starting with the fiber core as the initial layer, all identified cascaded transmission nodes in this layer are considered first-level nodes, interconnected by hydrogen bond networks in the core region. At the interface between the core and the transition region, covalent bond bridges exist, connecting cascaded transmission nodes in both the core and transition regions, establishing transmission paths from first-level nodes to second-level nodes. Cascaded transmission nodes within the transition region form a second-level network structure through the region's hydrogen bond network. Simultaneously, at the interface between the transition region and the surface region, covalent bond bridges again establish transmission paths to third-level nodes. Cascaded transmission nodes in the surface region constitute the third-level network, ultimately forming a hydrogen bond network cascaded transmission channel topology that runs from the fiber core to the surface, traversing all radial layers. This topology is mathematically described using a graph theory model, where nodes represent cascaded transmission nodes, edges represent hydrogen bond connections or covalent bond bridges, and the degree of a node reflects the connection density at that location.

[0046] The connection density distribution of cascaded transport nodes is obtained by calculating the product of the number of nodes per unit volume and the average degree of the nodes. Each radial layer is divided into equal-volume micro-elements. The number of nodes in each micro-element is counted, and the average degree of the nodes is calculated. The product of these two values ​​is the connection density of that micro-element. The radial distribution curve of the connection density reflects the spatial distribution characteristics of the cascaded transport channels of the hydrogen bond network. The transport of water molecules in the fiber depends on the continuity of the hydrogen bond network. Continuity is evaluated by calculating the proportion of cross-interface connection nodes between adjacent radial layers to the total number of nodes. This proportion needs to be greater than a preset continuity threshold of 60% to ensure that water molecules can be smoothly transported from one radial layer to the next through the hydrogen bond network. The transport efficiency is evaluated by calculating the ratio of the shortest path length of water molecules transported from the core to the surface to the actual path length. This ratio needs to be greater than a preset efficiency threshold of 75%, indicating that the paths of the cascaded transport channels of the hydrogen bond network are relatively direct, without excessive detours that would increase transport resistance.

[0047] In one optional embodiment, based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels, an in-situ hydrogel nanoarray with reversible phase transition properties is grown on the surface of the modified bio-based nylon fiber, comprising: Based on the hydrogen bond density values ​​of each radial layer, the hydrogen bond density reduction rate from the fiber core to the surface layer is calculated. The characteristic value of the hydrogen bond density of the fiber surface layer is determined according to the hydrogen bond density reduction rate and correlated with the density of hydrophilic functional groups on the fiber surface layer. The spatial location of the hydrogel monomer grafting site is then determined. Based on the topology of the cascaded transport channels, the spatial distribution density of the cascaded transport nodes from the fiber core to the fiber surface is statistically analyzed, and the water molecule transport active region on the fiber surface is determined as the growth site of the hydrogel nanounit based on the spatial distribution density. The spatial position of the hydrogel monomer grafting site is associated with the growth site, and the in-situ polymerization reaction of the hydrogel monomer is initiated at the hydrogel monomer grafting site at the growth site. By controlling the initiation density of the in-situ polymerization reaction and the degree of crosslinking of the polymer chain segments, hydrogel units with nanoscale spatial arrangement regularity are formed. Temperature-responsive and humidity-responsive molecular chain segments are introduced into the polymer network of the hydrogel unit. The reversible transition between the swelling and shrinkage states of the hydrogel unit is achieved through the synergistic response of the temperature-responsive and humidity-responsive molecular chain segments. The hydrogel units with reversible transition capabilities are assembled according to the nanoscale spatial arrangement rules to form a hydrogel nanoarray with reversible phase transition characteristics.

[0048] Cross-sections of modified bio-based nylon fibers were scanned using laser confocal microscopy. Hydrogen bond density distribution from the core to the surface was obtained by fluorescently labeling hydrogen bond sites. Twenty equally spaced measurement points were selected along the fiber radius, and the number of hydrogen bonds per unit volume within each measurement point region was counted. The local hydrogen bond density reduction rate was calculated by dividing the difference in hydrogen bond density between adjacent measurement points by the distance between the two points. A weighted average of all local reduction rates was then performed to obtain the overall hydrogen bond density reduction rate from the fiber core to the surface. Hydrogen bond density values ​​within approximately 200 nanometers of the fiber surface were extracted, and statistical analysis was performed on the hydrogen bond density within this region. The average value was calculated as the characteristic value of the hydrogen bond density of the fiber surface.

[0049] X-ray photoelectron spectroscopy (XPS) was used to perform elemental analysis on the fiber surface. The types and contents of hydrophilic functional groups on the fiber surface were quantitatively analyzed by detecting the characteristic peak positions and intensities of nitrogen and oxygen atoms. The fiber surface was divided into several nanoscale grid units, and the number of hydrophilic functional groups in each grid unit was counted, calculating the density distribution of functional groups per unit area. A correlation analysis was performed between the characteristic values ​​of hydrogen bond density and the density of hydrophilic functional groups to establish a quantitative correspondence between the two. Regions with high hydrogen bond density characteristic values ​​and moderate hydrophilic functional group density were selected as preferred grafting sites for hydrogel monomers. These sites possess sufficient reactivity while ensuring effective anchoring of the hydrogel monomers. The microenvironment around the selected sites was evaluated using molecular simulation software, confirming the existence of spatial channels near the grafting sites that allow access by hydrogel monomers. Finally, the three-dimensional spatial coordinates of the hydrogel monomer grafting sites were determined.

[0050] Small-angle X-ray scattering (SAXS) was used to characterize the cascaded transport channels within the fiber, obtaining their three-dimensional topological information. The fiber cross-section was divided into polar coordinates, with multiple concentric circular layers arranged radially. The number of cascaded transport nodes within each layer was counted. A cascaded transport node was defined as a hydrogen bond connection point formed by covalent bonds bridging adjacent radial layers. The spatial distribution density of cascaded transport nodes at different radial positions was calculated by dividing the number of nodes in each circular layer by the area of ​​that layer. The distribution density data was plotted as a radial distribution curve to identify regions with local maxima in node density. Regions on the fiber surface with node density greater than 1.5 times the overall average were selected; these regions correspond to the preferred destinations for water molecules transported from the fiber core.

[0051] Atomic force microscopy was used to scan the nanoscale morphology of the fiber surface, and force curve measurements were used to identify local differences in hydrophilicity. Spatial superposition analysis of regions with strong hydrophilicity and high-density regions of cascade transport nodes identified the overlapping areas as water molecule transport active regions. Within these active regions, water molecules can rapidly transport from the fiber interior to the surface and accumulate there. These water molecule transport active regions were marked as growth sites for hydrogel nanounits, where the hydrogel units can fully utilize the transported water molecules to participate in reversible phase transition processes.

[0052] The spatial coordinates of the hydrogel monomer grafting sites were matched with the spatial distribution of the growth sites, and sites that overlapped or were less than 5 nm apart were selected as the final hydrogel growth initiation points. A hydrogel precursor solution containing acrylic acid, 7-isopropylacrylamide, and a crosslinking agent was prepared, with a molar ratio of acrylic acid to 7-isopropylacrylamide of 3:7. Modified bio-based nylon fibers were immersed in the precursor solution, and ultrasonic assistance was used to ensure that the monomer molecules in the precursor solution were sufficiently close to the growth initiation points on the fiber surface. An azo initiator was introduced at the growth initiation point, and the initiator decomposed under ultraviolet light irradiation to generate free radicals. The intensity and duration of ultraviolet light irradiation were controlled to maintain the free radical initiation density at 3 to 8 initiation points per square nanometer.

[0053] The hydrogel monomers undergo in-situ polymerization initiated by free radicals. Acrylic units provide hydrophilic carboxyl groups, while 7-isopropylacrylamide units provide temperature responsiveness. During polymerization, the crosslinking agent reacts simultaneously with multiple polymer segments, forming a three-dimensional network structure. The degree of crosslinking of the polymer segments is controlled by adjusting the mass fraction of the crosslinking agent in the precursor solution, ranging from 0.8% to 1.5%. A lower degree of crosslinking allows the hydrogel units to maintain sufficient flexibility to respond to environmental changes, while a higher degree of crosslinking ensures the mechanical stability of the hydrogel units. After 30 to 60 minutes of polymerization, hydrogel units with a diameter of approximately 50 to 150 nanometers are formed on the fiber surface. The spacing between adjacent hydrogel units is controlled at 80 to 200 nanometers, resulting in a regular nanoscale spatial arrangement of the hydrogel units.

[0054] Temperature-responsive molecular segments are introduced into the polymer network of the hydrogel unit. These segments exhibit a hydrophilic extended state below the low critical solution temperature and transform into a hydrophobic contractile state above this temperature. The introduced humidity-responsive molecular segments contain multiple hydroxyl or carboxyl groups, which can form hydrogen bonds with water molecules in the environment. When the ambient humidity increases, a large number of water molecules are adsorbed onto the humidity-responsive segments, causing the polymer network to expand and enter a swollen state. When the ambient humidity decreases, the adsorbed water molecules are desorbed from the polymer network, the hydrophobic interactions between the polymer segments are enhanced, and the network shrinks. The temperature-responsive and humidity-responsive molecular segments are alternately distributed in the polymer network, and the response behaviors of the two types of segments influence each other, forming a synergistic effect.

[0055] Under conditions of rising temperature and decreasing humidity, temperature-responsive segments transform into a hydrophobic state, promoting network contraction, while humidity-responsive segments also tend to contract due to the loss of water molecules. The combined effect of these two factors causes the hydrogel unit to rapidly transition from a swollen state to a contracted state. Under conditions of decreasing temperature and rising humidity, temperature-responsive segments regain their hydrophilicity, while humidity-responsive segments adsorb water molecules, causing the hydrogel unit to re-swell. By precisely controlling the feed ratio of temperature-responsive monomers to humidity-responsive monomers during polymerization, the phase transition threshold of the hydrogel unit can be matched to the temperature and humidity variation range of human skin.

[0056] In one optional embodiment, the formation of a composite fiber structure with unidirectional moisture-wicking capability through the synergistic effect of the reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels includes: The water absorption response time of the hydrogel unit in the hydrogel nanoarray from the shrinking state to the swelling state and the dehydration response time from the swelling state to the shrinking state are monitored, and the phase transition time asymmetry characteristic parameter of the hydrogel nanoarray is determined based on the difference between the water absorption response time and the dehydration response time. The transfer time of water molecules from the fiber core to the fiber surface in the cascade transfer channel is extracted. The connection density distribution of the cascade transfer nodes in the cascade transfer channel is adjusted according to the time matching relationship between the transfer time and the water absorption response time, so that the water molecule transfer rate of the cascade transfer channel and the water absorption response rate of the hydrogel nanoarray are synchronized and coordinated. Based on the phase transition time asymmetry characteristic parameter, when the humidity of the external environment of the fiber is higher than that of the internal environment of the fiber, the hydrogel nanoarray maintains a swollen state to prevent external water molecules from penetrating into the fiber. When the humidity of the external environment of the fiber is lower than that of the internal environment of the fiber, the hydrogel nanoarray quickly transforms into a contracted state to release water molecules to the external environment. At the same time, based on the synchronous and synergistic maintenance of the cascaded transfer channel, water molecules inside the fiber are transferred to the surface, forming the composite fiber structure with unidirectional moisture-wicking capability.

[0057] When constructing composite fiber structures with unidirectional moisture-wicking capabilities, it is necessary to precisely coordinate the reversible phase transition behavior of the hydrogel nanoarray with the water molecule transport dynamics of the cascaded transport channels. The hydrogel nanoarray on the surface of the modified bio-based nylon fiber is composed of poly(7-isopropylacrylamide) and acrylamide copolymer units. The diameter of each hydrogel unit is controlled within the range of 80-150 nm, and the center-to-center spacing between array units is maintained at 200-300 nm, ensuring that adjacent units can form a continuous water molecule barrier layer in the swollen state. The hydrogel units are chemically bonded to the amino groups on the fiber surface through a silane coupling agent, achieving an anchoring density of 15-25 anchoring points per square micrometer.

[0058] To monitor the phase transition response characteristics of hydrogel nanoarrays, a micro-humidity sensor array was used to track the volume changes of individual hydrogel units in real time. When the relative humidity of the environment suddenly increased from 40% to 85%, the hydrophilic segments inside the hydrogel units began to absorb water molecules. The reconstruction of the hydrogen bond network caused the polymer chains to extend, and the unit volume expanded to 2.5-3.2 times its initial volume within 8-12 seconds, entering a fully swollen state. At this time, the gaps between the hydrogel units were filled, forming a continuous hydration layer with a thickness of approximately 200-280 nanometers on the fiber surface. Water molecules in this hydration layer were bound inside the hydrogel network through the hydrogen bond network, effectively preventing liquid water or high-humidity air from the external environment from penetrating into the fiber interior.

[0059] When the relative humidity drops from 85% to 40%, water molecules inside the hydrogel unit begin to diffuse outward, and the polymer chain segments collapse, shrinking the unit volume to its original state within 3-5 seconds. There is a significant difference between this water absorption response time and the dehydration response time; the water absorption process takes 8-12 seconds, while the dehydration process only takes 3-5 seconds. The phase transition time asymmetry characteristic parameter is defined as the ratio of the dehydration response time to the water absorption response time, which is typically between 0.25 and 0.45. This time asymmetry is key to achieving unidirectional moisture wicking. The rapid response of the dehydration process ensures that water molecules inside the fiber can be quickly released to the external environment, while the slow response of the water absorption process provides sufficient barrier time in high-humidity external environments.

[0060] The transport dynamics of water molecules in the cascaded transport channels directly affect the unidirectional moisture wicking efficiency. The radial distance from the fiber core to the surface is typically 15-25 micrometers. The cascaded transport channels are composed of covalently bonded bridging structures between different radial layers, with each bridging node containing 2-4 covalently linked sites of carboxyl and hydroxyl groups. Water molecules enter the cascaded transport channels under the adsorption of hydrophilic groups in the core and are transferred between adjacent radial layers in a skip-transfer manner through a hydrogen bond network. The time for a single water molecule to be transferred from the core to the surface is modulated by the connection density of the cascaded transport nodes. When the connection density is 80-120 nodes per cubic micrometer, the water molecule transport time is approximately 6-9 seconds, which is basically matched with the water absorption response time of 8-12 seconds for the hydrogel nanoarray, forming a temporally synchronized synergistic relationship.

[0061] When controlling the connection density distribution of cascade transport nodes, a refined design is required based on the hydrogen bond density characteristics at different radial positions of the fiber. In the inner layer region, 5-8 micrometers from the fiber's central axis, the hydrogen bond density is high, and the connection density of the cascade transport nodes is set to 100-130 per cubic micrometer to provide a faster water molecule transport rate. In the middle layer region, 8-15 micrometers from the central axis, the connection density is adjusted to 70-95 per cubic micrometer, and the water molecule transport rate is appropriately reduced to match the response characteristics of the outer hydrogel array. In the outer layer region, above 15 micrometers from the central axis, the connection density is controlled at 50-70 per cubic micrometer to form a buffer layer in direct contact with the hydrogel nanoarray, preventing the surface hydrogel units from being unable to respond quickly enough due to an excessively fast water molecule transport rate.

[0062] The unidirectional moisture-wicking capability relies on the coupling effect of phase transition time asymmetry and synchronous synergy. When the human body sweats during exercise, the internal humidity of the fiber increases rapidly, and water molecules are transferred from the core to the surface driven by the asymmetric molecular gradient structure. Because the transfer time of the cascaded transfer channels matches the water absorption response time of the hydrogel nanoarray, when water molecules reach the fiber surface, the surface hydrogel units have not yet fully swelled. At this time, water molecules can be released into the external environment through the gaps between the hydrogel arrays. When the external humidity is higher than the internal humidity of the fiber, such as in a static state in a high-humidity environment, the hydrogel nanoarray fully swells within 8-12 seconds, forming a continuous barrier layer. External water molecules cannot penetrate into the fiber interior, keeping the fiber interior dry.

[0063] The unidirectional moisture-wicking capacity of the composite fiber structure is quantitatively evaluated using the moisture wicking index, defined as the ratio of the number of water molecules transferred from the inside to the outside of the fiber per unit time to the number of water molecules penetrating from the outside to the inside. Under standard test conditions of 65% relative humidity and 25 degrees Celsius, the optimized composite fiber structure achieves a moisture wicking index of 15-25, indicating that the rate of water molecule transfer from the inside to the outside is 15-25 times faster than the rate of water penetration from the outside to the inside. This significant unidirectional moisture-wicking capacity ensures that the bio-based nylon fiber can quickly wick away sweat produced by the human body during actual wear, while effectively preventing moisture from the external environment from penetrating into the fiber, significantly improving the fabric's moisture absorption and wicking performance and wearing comfort.

[0064] By regulating the chemical composition of the hydrogel nanoarray, the phase transition time asymmetry characteristic parameters can be further optimized. Increasing the molar ratio of poly-7-isopropylacrylamide can shorten the dehydration response time and increase the rate of transition from swelling to shrinkage, enabling the composite fiber structure to maintain efficient unidirectional moisture wicking capacity even when a large amount of sweat is generated during rapid exercise.

[0065] In one optional embodiment, based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase transition threshold of the hydrogel nanoarray, the optimal matching relationship between the hydrogen bond cascade transport rate and the phase transition response time of the nanoarray under different humidity loads is calculated. Combined with the unidirectional moisture-wicking capacity parameters of the composite fiber structure, an optimized control scheme for the fiber's moisture absorption and perspiration performance is generated, including: Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure, the energy barrier distribution of water molecules between each radial layer during the dynamic equilibrium of hydrogen bond breaking and recombination is calculated, and the hydrogen bond cascade transport kinetic parameters are determined according to the energy barrier distribution. Calculate the critical environmental temperature and humidity conditions required for the hydrogel nanoarray to transition from a contracted state to a swollen state and from a swollen state to a contracted state, and determine the reversible phase transition threshold of the hydrogel nanoarray based on the critical environmental temperature and humidity conditions. The time matching coefficient between the hydrogen bond cascade transport rate inside the asymmetric molecular gradient structure and the phase transition response time of the hydrogel nanoarray surface is calculated based on the hydrogen bond cascade transport kinetic parameters and the reversible phase transition threshold under different humidity loads. The optimal matching relationship between the hydrogen bond cascade transport rate and the nanoarray phase transition response time is determined based on the time matching coefficient. By regulating the radial distribution density of hydrophilic functional groups in the asymmetric molecular gradient structure and the degree of crosslinking of polymeric segments in the hydrogel nanoarray, the hydrogen bond cascade transfer rate and the phase transition response time of the nanoarray satisfy the optimal matching relationship, thereby generating an optimized regulation scheme for the moisture absorption and perspiration performance of the fiber.

[0066] Following the formation of the aforementioned modified bio-based nylon fiber, its moisture-wicking properties require in-depth optimization and control. Firstly, the hydrogen bond network in the asymmetric molecular gradient structure is quantitatively characterized using Fourier transform infrared spectroscopy combined with deuterated solvent exchange technology to determine the type and number density of hydrogen bonds in each radial layer from the core to the surface. The fiber is divided radially into three typical regions: a core region, an intermediate transition region, and a surface region. X-ray photoelectron spectroscopy is used to analyze the distribution and concentration of hydrophilic functional groups such as carboxyl and hydroxyl groups in each region. In the core region, the molar concentration of hydrophilic groups is typically in the range of 8-12 mmol / g, decreasing to 4-7 mmol / g in the intermediate transition region, and further decreasing to 1-3 mmol / g in the surface region, forming a significant concentration gradient.

[0067] Based on the hydrogen bond density distribution data mentioned above, molecular dynamics simulations were used to calculate the energy barriers that water molecules need to overcome during migration between radial layers. At the interface between the core region and the intermediate transition region, due to the significant difference in hydrogen bond density, water molecules need to break the existing hydrogen bond network and form new hydrogen bonds in the new environment. The activation energy for this process is typically 35-45 kJ / mol. During the transfer from the intermediate transition region to the surface region, due to the weaker hydrophilicity of the surface layer, water molecules tend to exist in the form of free water, and the energy barrier drops to 20-30 kJ / mol. By correlating temperature and transfer rate using the Arrhenius equation, under human skin temperature conditions of 32-36℃, the diffusion coefficient of water molecules from the core region to the intermediate region is approximately 2.5 × 10⁻⁶. -10 m 2 / s, the diffusion coefficient from the intermediate region to the surface region increases to 6.8×10 -10 m 2 / s. These parameters constitute the core dataset of hydrogen bond cascade transport dynamics.

[0068] To investigate the reversible phase transition behavior of hydrogel nanoarrays, the morphological changes of the nanoarrays under different temperature and humidity conditions were observed using environmentally controlled scanning electron microscopy. When the relative humidity was below 40% and the temperature was above 35℃, the hydrogel polymer segments shrank due to water loss, causing the nanoarray height to decrease from the initial 200-300 nm to 80-120 nm, the porosity to decrease from 65% to 30%, and the surface contact angle to increase from 45° to 85°. When the relative humidity increased to above 65% and the temperature decreased to below 28℃, the polymer segments absorbed water and swelled, causing the nanoarray to expand back to its original size, the porosity to recover, and the contact angle to decrease. The critical phase transition point was precisely determined using differential scanning calorimetry (DSC). It was found that at 60% relative humidity, the temperature threshold was 31.5 ± 0.8℃; when the relative humidity increased to 80%, the temperature threshold decreased to 29.2 ± 0.6℃. These critical condition parameters define the reversible phase transition threshold of the hydrogel nanoarrays.

[0069] After obtaining the hydrogen bond cascade transport kinetic parameters and phase transition threshold, a coupled computational model was established to evaluate the synergistic effect of the two. Different humidity load scenarios were set, such as 150-250 g / m² of moisture generated per hour on the skin surface under moderate exercise intensity. 2 Sweat production during high-intensity exercise can reach 400-600 g / m³. 2 Under moderate humidity loads, after absorbing moisture, the fiber core transfers it outward through hydrogen bond cascade channels. According to the aforementioned diffusion coefficient, the time required for moisture to reach the surface from the core is approximately 8-12 seconds. If the phase transition response time of the hydrogel nanoarray is 6-9 seconds, it means that the nanoarray has completed the transformation from shrinkage to swelling before the moisture reaches the surface. The resulting hydrophilic surface can rapidly absorb and release moisture, achieving highly efficient moisture wicking. The time-matching coefficient is defined as the ratio of the hydrogen bond cascade transfer time to the phase transition response time, with an optimal range of 0.8-1.3, at which point the moisture absorption rate and perspiration rate reach the best balance.

[0070] When humidity load increases to high-intensity exercise levels, the hydrogen bond cascade transport rate needs to be increased accordingly. By increasing the density of hydrophilic groups in the intermediate transition region, raising the carboxyl group concentration in this region from 5 mmol / g to 7 mmol / g, the overall diffusion coefficient can be increased by approximately 30%, and the transport time shortened to 5-8 seconds. Simultaneously adjusting the crosslinking degree of polymer segments in the hydrogel nanoarray from the initial 15% to 10% enhances segment flexibility, accelerating the phase transition response time to 4-6 seconds. At this point, the time-matching coefficient is maintained at 1.0-1.4, ensuring rapid perspiration while preventing surface moisture accumulation.

[0071] For low humidity load scenarios, such as when sitting or engaging in light activity, the output is 50-100 g / m³ per hour. 2The trace amounts of sweat can appropriately reduce the hydrogen bond cascade transfer rate, thereby extending the fiber's moisture absorption and buffering capacity. By reducing the covalent bond bridging density at the interface between the core and intermediate regions, the energy barrier is increased to 50 kJ / mol, extending the transfer time to 15-20 seconds. Correspondingly, the cross-linking degree of the hydrogel nanoarray is increased to 20%, enhancing structural stability, extending the phase transition response time to 12-16 seconds, and maintaining the time-matching coefficient at 0.9-1.2, achieving slow and continuous moisture regulation.

[0072] Based on the calculation results from the different scenarios described above, a systematic optimization and control scheme is formulated. This scheme comprises three core control dimensions: First, by adjusting the plasma processing power and grafting reaction time, the distribution density of hydrophilic groups in each radial layer is precisely controlled. The core region maintains a high density to ensure moisture absorption capacity, the intermediate region is adjusted within the range of 4-8 mmol / g according to the target application scenario, and the surface region maintains a low density to ensure hydrophobic wicking. Second, by changing the hydrogel monomer ratio and polymerization conditions, the degree of crosslinking is controlled within the range of 8%-22% to match different phase transition response requirements. Third, a real-time monitoring system is introduced, using miniature humidity sensors embedded within the fiber to provide feedback on the actual humidity load and dynamically adjust the fiber structural parameters. The optimization scheme is stored in a database containing optimal parameter configurations under different combinations of temperature, humidity, and activity intensity, enabling intelligent adaptive control of the fiber's moisture absorption and wicking performance.

[0073] A second aspect of the present invention provides a system for optimizing the moisture-wicking performance of bio-based nylon fibers, comprising: The gradient building unit is used to construct an asymmetric molecular gradient structure that exhibits a nonlinear decrease in hydrophilicity from the fiber core to the surface by introducing functional groups with different hydrophilicities into different radial regions of the fiber cross-section through a plasma-assisted directional grafting reaction based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated. Channel forming units are used to form cascaded transport channels by connecting the hydrogen bond network between each radial layer of the asymmetric molecular gradient structure through covalent bonds, thereby obtaining modified bio-based nylon fibers with radial asymmetric hydrophilic gradients. An array growth unit is used to grow a hydrogel nanoarray with reversible phase transition properties in situ on the surface of the modified bio-based nylon fiber, based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels. Synergistic unit, used to form a composite fiber structure with unidirectional moisture-wicking capability through the synergistic effect of the reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels; The regulation scheme unit is used to calculate the optimal matching relationship between the hydrogen bond cascade transport rate and the phase change response time of the nanoarray under different humidity loads based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase change threshold of the hydrogel nanoarray, and generate an optimized regulation scheme for the moisture absorption and perspiration performance of the fiber by combining the unidirectional moisture-wicking capacity parameter of the composite fiber structure.

[0074] A third aspect of the present invention provides an electronic device, comprising: processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the aforementioned method.

[0075] A fourth aspect of the present invention provides a computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, implement the aforementioned method.

[0076] This invention can be a method, apparatus, system, and / or computer program product. The computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for performing various aspects of the invention.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for optimizing the moisture absorption and wicking properties of bio-based nylon fibers, characterized in that, include: Based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated, a plasma-assisted directional grafting reaction was used to introduce functional groups with different hydrophilicities in different radial regions of the fiber cross-section, thereby constructing an asymmetric molecular gradient structure with nonlinear decrease in hydrophilicity from the fiber core to the surface. The hydrogen bond network between the radial layers of the asymmetric molecular gradient structure forms a cascaded transmission channel through covalent bond bridging, resulting in modified bio-based nylon fibers with radial asymmetric hydrophilic gradients. Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels, a hydrogel nanoarray with reversible phase transition properties is grown in situ on the surface of the modified bio-based nylon fiber. Through the synergistic effect of the reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels, a composite fiber structure with unidirectional moisture-wicking capability is formed. Based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase transition threshold of the hydrogel nanoarray, the optimal matching relationship between the hydrogen bond cascade transport rate and the phase transition response time of the nanoarray under different humidity loads is calculated. Combined with the unidirectional moisture-wicking capacity parameters of the composite fiber structure, an optimized control scheme for the moisture absorption and perspiration performance of the fiber is generated.

2. The method according to claim 1, characterized in that, Based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated, a plasma-assisted directional grafting reaction was used to introduce functional groups with differentiated hydrophilicity into different radial regions of the fiber cross-section, constructing an asymmetric molecular gradient structure exhibiting a non-linear decrease in hydrophilicity from the fiber core to the surface, including: The spatial distribution information of amide groups and the coordination state information of hydrogen bond interaction sites in the corresponding molecular chain segments of the bio-based nylon fiber to be processed are obtained by spectral analysis technology. Based on the spatial distribution information of amide groups and the coordination state information of hydrogen bond interaction sites, a three-dimensional spatial mapping relationship of hydrogen bond network topology is constructed. Based on the density distribution gradient of hydrogen bond interaction sites in the three-dimensional spatial mapping relationship, the plasma bombardment energy distribution scheme and the radial stratification selection rule of grafting reaction active sites corresponding to different radial regions of the fiber cross section are determined. According to the plasma bombardment energy distribution scheme, the surface of the bio-based nylon fiber to be treated is subjected to regional plasma treatment to form a free radical distribution layer with different activity levels in different radial regions of the fiber cross-section. According to the radial stratification selection rule of the grafting reaction active sites, functional groups with different hydrophilic segment lengths are grafted to the active sites in the corresponding radial regions of the free radical distribution layer to construct an asymmetric molecular gradient structure with nonlinear decrease in hydrophilicity from the fiber core to the surface.

3. The method according to claim 2, characterized in that, Based on the density distribution gradient of hydrogen bond interaction sites in the aforementioned three-dimensional spatial mapping relationship, the plasma bombardment energy distribution scheme and the radial stratification selection rule for grafting reaction active sites corresponding to different radial regions of the fiber cross-section are determined, including: Based on the gradient change rate of hydrogen bond density between adjacent radial regions, a monotonically decreasing correspondence between the radial region index and the plasma bombardment energy requirement is constructed, and the fiber cross-section is divided into multiple radial levels in the order from the core to the surface. In each radial level, plasma bombardment energy values ​​are allocated to each radial level according to the inverse proportional relationship between the corresponding hydrogen bond density value and the plasma bombardment energy requirement value. The plasma bombardment energy values ​​corresponding to each radial level are summarized to form the plasma bombardment energy distribution scheme corresponding to different radial regions of the fiber cross-section. Based on the coordination saturation parameters of each hydrogen bond interaction site, unsaturated hydrogen bond interaction sites in each radial region are identified as preferred active sites for the grafting reaction. The length range of the hydrophilic chain segment of the functional group that is suitable for each radial region is determined according to the distribution range of the coordination saturation parameter. The sequence of the preferred treatment site for grafting reaction in each radial region is determined according to the spatial distribution of the preferred active site. The length range of the hydrophilic chain segment of the functional group corresponding to each radial region is associated with the sequence of the preferred treatment site to form the radial stratification selection rule of the active site for grafting reaction.

4. The method according to claim 1, characterized in that, The hydrogen bond network between the radial layers of the asymmetric molecular gradient structure forms a cascade transport channel through covalent bond bridging, resulting in modified bio-based nylon fibers with radial asymmetric hydrophilic gradients, including: The interface region between adjacent radial layers in the asymmetric molecular gradient structure is cross-linked to form a covalent bridge structure between the grafted functional groups between adjacent radial layers. The spatial coordinate information and covalent bond length information of the covalent bridging structure are obtained. The interface position of the covalent bridging structure in each radial layer is determined according to the spatial coordinate information. The spatial distance between the grafted functional groups of adjacent radial layers connected by each covalent bridging structure is calculated according to the covalent bond length information. The hydrogen bond interaction sites corresponding to the grafted functional groups whose spatial distance is less than a preset hydrogen bond interaction distance threshold are identified as cascade transfer nodes. Based on the spatial positional relationship of the cascaded transmission nodes in each radial layer, a hydrogen bond network cascaded transmission channel topology is constructed that runs from the fiber core to the surface layer and through each radial layer. Based on the connection density distribution of the cascaded transport nodes in the hydrogen bond network cascaded transport channel topology, the continuity and efficiency of water molecule transport between each radial layer are evaluated. The fibers corresponding to the hydrogen bond network cascaded transport channel topology that satisfy a preset continuity threshold and a preset efficiency threshold are identified as modified bio-based nylon fibers with radial asymmetric hydrophilic gradients.

5. The method according to claim 3, characterized in that, Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels, a hydrogel nanoarray with reversible phase transition properties is grown in situ on the surface of the modified bio-based nylon fiber, comprising: Based on the hydrogen bond density values ​​of each radial layer, the hydrogen bond density reduction rate from the fiber core to the surface layer is calculated. The characteristic value of the hydrogen bond density of the fiber surface layer is determined according to the hydrogen bond density reduction rate and correlated with the density of hydrophilic functional groups on the fiber surface layer. The spatial location of the hydrogel monomer grafting site is then determined. Based on the topology of the cascaded transport channels, the spatial distribution density of the cascaded transport nodes from the fiber core to the fiber surface is statistically analyzed, and the water molecule transport active region on the fiber surface is determined as the growth site of the hydrogel nanounit based on the spatial distribution density. The spatial position of the hydrogel monomer grafting site is associated with the growth site, and the in-situ polymerization reaction of the hydrogel monomer is initiated at the hydrogel monomer grafting site at the growth site. By controlling the initiation density of the in-situ polymerization reaction and the degree of crosslinking of the polymer chain segments, hydrogel units with nanoscale spatial arrangement regularity are formed. Temperature-responsive and humidity-responsive molecular chain segments are introduced into the polymer network of the hydrogel unit. The reversible transition between the swelling and shrinkage states of the hydrogel unit is achieved through the synergistic response of the temperature-responsive and humidity-responsive molecular chain segments. The hydrogel units with reversible transition capabilities are assembled according to the nanoscale spatial arrangement rules to form a hydrogel nanoarray with reversible phase transition characteristics.

6. The method according to claim 1, characterized in that, The reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels work together to form a composite fiber structure with unidirectional moisture-wicking capability, comprising: The water absorption response time of the hydrogel unit in the hydrogel nanoarray from the shrinking state to the swelling state and the dehydration response time from the swelling state to the shrinking state are monitored, and the phase transition time asymmetry characteristic parameter of the hydrogel nanoarray is determined based on the difference between the water absorption response time and the dehydration response time. The transfer time of water molecules from the fiber core to the fiber surface in the cascade transfer channel is extracted. The connection density distribution of the cascade transfer nodes in the cascade transfer channel is adjusted according to the time matching relationship between the transfer time and the water absorption response time, so that the water molecule transfer rate of the cascade transfer channel and the water absorption response rate of the hydrogel nanoarray are synchronized and coordinated. Based on the phase transition time asymmetry characteristic parameter, when the humidity of the external environment of the fiber is higher than that of the internal environment of the fiber, the hydrogel nanoarray maintains a swollen state to prevent external water molecules from penetrating into the fiber. When the humidity of the external environment of the fiber is lower than that of the internal environment of the fiber, the hydrogel nanoarray quickly transforms into a contracted state to release water molecules to the external environment. At the same time, based on the synchronous and synergistic maintenance of the cascaded transfer channel, water molecules inside the fiber are transferred to the surface, forming the composite fiber structure with unidirectional moisture-wicking capability.

7. The method according to claim 1, characterized in that, Based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase transition threshold of the hydrogel nanoarray, the optimal matching relationship between the hydrogen bond cascade transport rate and the phase transition response time of the nanoarray under different humidity loads is calculated. Combined with the unidirectional moisture-wicking capacity parameters of the composite fiber structure, an optimized control scheme for the fiber's moisture absorption and perspiration performance is generated, including: Based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure, the energy barrier distribution of water molecules between each radial layer during the dynamic equilibrium of hydrogen bond breaking and recombination is calculated, and the hydrogen bond cascade transport kinetic parameters are determined according to the energy barrier distribution. Calculate the critical environmental temperature and humidity conditions required for the hydrogel nanoarray to transition from a contracted state to a swollen state and from a swollen state to a contracted state, and determine the reversible phase transition threshold of the hydrogel nanoarray based on the critical environmental temperature and humidity conditions. The time matching coefficient between the hydrogen bond cascade transport rate inside the asymmetric molecular gradient structure and the phase transition response time of the hydrogel nanoarray surface is calculated based on the hydrogen bond cascade transport kinetic parameters and the reversible phase transition threshold under different humidity loads. The optimal matching relationship between the hydrogen bond cascade transport rate and the nanoarray phase transition response time is determined based on the time matching coefficient. By regulating the radial distribution density of hydrophilic functional groups in the asymmetric molecular gradient structure and the degree of crosslinking of polymeric segments in the hydrogel nanoarray, the hydrogen bond cascade transfer rate and the phase transition response time of the nanoarray satisfy the optimal matching relationship, thereby generating an optimized regulation scheme for the moisture absorption and perspiration performance of the fiber.

8. A system for optimizing the moisture-wicking properties of bio-based nylon fibers, used to implement the method as described in any one of claims 1-7, characterized in that, include: The gradient building unit is used to construct an asymmetric molecular gradient structure that exhibits a nonlinear decrease in hydrophilicity from the fiber core to the surface by introducing functional groups with different hydrophilicities into different radial regions of the fiber cross-section through a plasma-assisted directional grafting reaction based on the hydrogen bond network topology of the corresponding molecular chain segments of the bio-based nylon fiber to be treated. Channel forming units are used to form cascaded transport channels by connecting the hydrogen bond network between each radial layer of the asymmetric molecular gradient structure through covalent bonds, thereby obtaining modified bio-based nylon fibers with radial asymmetric hydrophilic gradients. An array growth unit is used to grow a hydrogel nanoarray with reversible phase transition properties in situ on the surface of the modified bio-based nylon fiber, based on the hydrogen bond density distribution characteristics of each radial layer in the asymmetric molecular gradient structure and the connectivity of the cascade transport channels. Synergistic unit, used to form a composite fiber structure with unidirectional moisture-wicking capability through the synergistic effect of the reversible phase transition behavior of the hydrogel nanoarray and the cascaded transport channels; The regulation scheme unit is used to calculate the optimal matching relationship between the hydrogen bond cascade transport rate and the phase change response time of the nanoarray under different humidity loads based on the coupling relationship between the hydrogen bond cascade transport kinetics of the asymmetric molecular gradient structure and the reversible phase change threshold of the hydrogel nanoarray, and generate an optimized regulation scheme for the moisture absorption and perspiration performance of the fiber by combining the unidirectional moisture-wicking capacity parameter of the composite fiber structure.

9. An electronic device, characterized in that, include: processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having computer program instructions stored thereon, characterized in that, When the computer program instructions are executed by the processor, they implement the method described in any one of claims 1 to 7.

Images