Fiber membrane with continuous cooling and moisture regulation properties, preparation method and application thereof

Abstract

The present invention belongs to the field of functional fiber technology and relates to a fiber membrane having both continuous cooling and moisture regulating properties, and its preparation method and application. The preparation method is: after respectively configuring the skin spinning solution and the core layer spinning solution, coaxial electrospinning is performed to obtain a fiber membrane having both continuous cooling and moisture regulating properties. The constituent fibers of the fiber membrane having both continuous cooling and moisture regulating properties have a skin-core structure, the skin layer includes a skin base material and functional particles, the core layer has phase change characteristics, the phase change temperature of the core layer is 28-32°C, and the functional particles have the characteristic of absorbing sweat vapor. The fiber membrane having both continuous cooling and moisture regulating properties of the present invention can be applied to personal protection, outdoor sports, aerospace or military equipment fields.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional fibers, and relates to a fiber membrane having both continuous cooling and moisture regulating properties, and a preparation method and application thereof. Background Art

[0002] In hot environments, the human body dissipates heat through sweating and other methods. However, if clothing fails to dissipate this heat in a timely manner, the body will feel stuffy and uncomfortable. Furthermore, the body produces a large amount of sweat during this heat dissipation process. If clothing fails to effectively remove moisture, sweat accumulates on the skin's surface, not only exacerbating the feeling of stuffiness but also potentially causing skin discomfort and bacterial growth, further impacting human health and comfort. Furthermore, when the environment is dry, moisture from the human skin evaporates faster, and excessive dryness can cause skin tightness, itching, and flaking. Therefore, whether in hot and humid environments or dry environments, temperature regulation and moisture regulation (i.e., the ability to dynamically adjust the relative humidity of the body-fabric microenvironment to avoid excessive moisture or dryness) are crucial for maintaining human comfort and health.

[0003] As people's quality of life improves and they pursue a healthier and more comfortable lifestyle, consumers are demanding more and more comfort in their clothing. Temperature and moisture regulation have become key elements in determining textile quality. Sustained cooling (i.e., the ability to absorb moisture from the skin, causing the surface temperature to drop, resulting in a continuous cool sensation) is a crucial characteristic of temperature regulation, particularly in hot environments. It plays a crucial role in regulating the body's microenvironmental temperature and enhancing wearing comfort.

[0004] However, existing technologies often cannot provide both continuous cooling and moisture regulation.

[0005] For example, patent application CN115559020A describes a composite phase-change thermoregulatory material made by mixing and granulating a polymer-based phase-change thermoregulatory material, phase-change thermoregulatory microcapsules containing polyoxymethylene melamine urea capsule walls, and a high-thermal-conductivity powder. The composite material is then melt-spun with a low-melting-point polyester core layer and a fiber-forming polymer and thermally conductive material as the sheath layer. The resulting fiber exhibits sustained thermoregulatory properties. However, the fiber lacks either sustained cooling or moisture-regulating properties.

[0006] 37.5™ technology embeds volcanic sand or coconut shell activated carbon particles into the fabric, adding a water-release mechanism to natural fibers, reducing microclimate moisture levels and improving garment comfort. It achieves temperature regulation through a dual mechanism: first, it uses electrostatic forces to attract moisture, drawing it away from the skin to dry the microclimate; second, it absorbs infrared energy naturally emitted by the body, accelerating molecular thermal motion and thus sweat evaporation. However, the volcanic sand or coconut shell activated carbon particles used in this technology are micron-sized and are currently primarily added to yarns. This makes it impossible to create nanofibers or yarns, and it also lacks the ability to provide a sustained cooling effect.

[0007] Outlast ® Constant temperature technology relies on a solid-liquid phase change material (microencapsulated natural wax) that is infiltrated into fabrics or fibers. When the ambient temperature rises due to factors such as exercise, the natural wax absorbs excess heat and stores it in the textile. When the temperature drops, the wax resolidifies, releasing the stored heat back into the body, thus achieving active heat management. However, this technology cannot regulate the humidity in the microenvironment. Summary of the Invention

[0008] The purpose of the present invention is to solve the problems existing in the prior art and provide a fiber membrane with both continuous cooling and moisture regulating properties, as well as a preparation method and application thereof.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] A fiber membrane that has both a continuous cooling sensation and moisture-regulating properties. Its constituent fibers have a skin-core structure, with the skin layer including a skin substrate and functional particles. The core layer has phase change properties, and the functional particles have the property of absorbing sweat vapor. The phase change temperature of the core layer is 28-32°C, close to the human body's comfortable temperature range (usually around 28°C). When the ambient temperature exceeds this phase change temperature, the core layer absorbs heat through phase change, thereby lowering the temperature around the human body.

[0011] The constituent fibers of the fiber membrane of the present invention have a continuous cooling property because when the fiber contacts the human body, the core layer with phase change properties is activated, and the heat of the human body is effectively absorbed through the fiber, lowering the core temperature of the human body, thereby maintaining a comfortable microclimate. As the ambient temperature rises or physical activity intensifies, the core body temperature rises, inducing the generation of sweat vapor, which triggers the adsorption of functional particles in the fiber. At the same time, the latent heat absorbed by the core layer with phase change properties is effectively used to promote water evaporation, and the released water further enhances the evaporative cooling effect. Therefore, this establishes a self-sustaining positive feedback loop, that is, the water release caused by the phase change promotes continuous adsorption, and the adsorption further promotes the phase change, synergistically amplifying the overall cooling effect.

[0012] In addition, the constituent fibers of the fiber membrane of the present invention also have moisture regulation properties. Because the functional particles in the fibers have a porous structure, a high specific surface area, and adsorption properties, the fibers can dynamically adjust their ability to absorb and release moisture. When the relative humidity of the environment is high (such as when the human body sweats), the fibers can quickly absorb sweat vapor to reduce the feeling of stuffiness; when the environment is dry, the fibers can gradually release the stored moisture, thereby maintaining the relative humidity balance and stability of the microenvironment (such as when the environment is dry). Figure 1 shown).

[0013] The functional particles in the fibers that make up existing fiber membranes lack the ability to absorb sweat vapor. Therefore, they cannot effectively absorb the moisture and heat released by sweating, causing sweat to accumulate on the skin surface and hindering the evaporative cooling effect. Furthermore, due to the lack of active sweat vapor adsorption, the heat and moisture exchange efficiency within the fibers is low, and evaporation cannot promptly remove body heat. Consequently, they lack sustained cooling properties and moisture regulation capabilities.

[0014] As the preferred technical solution:

[0015] In the fiber membrane having both continuous cooling and moisture regulating properties as described above, the functional particles are activated carbon and / or nano-mineral materials.

[0016] The fiber membrane having both continuous cooling and moisture regulating properties as described above has a pore size of 10-100 nm, a porosity of ≥85%, and a specific surface area of ​​500-1500 m 2 / g, the particle size is 0.1-2μm, and the adsorption capacity for water vapor is ≥200mg / g under the conditions of temperature of 25℃ and relative humidity of 90%.

[0017] As described above, the fiber membrane has both continuous cooling and moisture regulating properties, and the skin base material is PU (polyurethane).

[0018] In the fiber membrane having both continuous cooling and moisture regulating properties as described above, the mass ratio of the cortex substrate to the functional particles is 1:0.05-0.5.

[0019] The fiber membrane having both continuous cooling and moisture regulating properties as described above has a core layer made of solid-solid phase change material.

[0020] The core layer of the fiber in the prior art is a solid-liquid phase change material, which is prone to leakage. The present invention solves the leakage problem by designing the core layer to be a solid-solid phase change material.

[0021] As described above, a fiber membrane having both continuous cooling and moisture regulating properties has a core layer which is a blend of PEG (polyethylene glycol) and PU in a mass ratio of 1:0.5-5, the number average molecular weight of PEG is ≤800 g / mol, and the melting point of PU is 60-100°C.

[0022] The core layer can also be a blend of PI (polyimide) or PVDF (polyvinylidene fluoride) with a suitable melting point and a suitable molecular weight.

[0023] The fiber membrane having both continuous cooling and moisture regulating properties as described above has a circular cross-section of its constituent fibers, a core layer with a diameter of 500-1000 nm, and a skin layer with a thickness of 100-500 nm.

[0024] The fiber membrane having both continuous cooling and moisture regulating properties as described above has a moisture permeability of 8.15-10.14 kg·m -2 ·d -1 The dry breaking strength is 3.47-5.88MPa, the wet breaking strength is 2.61-8.47MPa, the Q-max value (contact cooling coefficient, an important indicator to measure the cooling performance of the fabric, which indicates the maximum value of heat loss at the moment of contact between the skin and the fabric. When the Q-max value is ≥0.15, it is considered to have contact cooling performance) is 0.28-0.43W / cm², the cooling duration (the length of time the fabric can continue to provide a cooling sensation after contacting the skin) is 45-60min, and the moisture regulation efficiency is 0.01-2% / min.

[0025] The present invention also provides a method for preparing a fiber membrane having both continuous cooling and moisture regulating properties as described in any of the above items. After respectively preparing the skin layer spinning solution and the core layer spinning solution, coaxial electrospinning is performed to obtain a fiber membrane having both continuous cooling and moisture regulating properties.

[0026] As the preferred technical solution:

[0027] As described above, the process parameters of coaxial electrospinning include: injection rate of skin spinning solution 2-5 mL / h, injection rate of core spinning solution 0.3-1.5 mL / h, spinning voltage 18-22 kV, spinning distance 20-30 cm, ambient temperature 20-30 ° C, ambient relative humidity 30-70%, slide moving speed 50-100 cm / min, and receiving roller speed 50-100 r / min.

[0028] The present invention also provides an application of a fiber membrane having both continuous cooling and moisture regulating properties as described in any one of the above items, for use in personal protection, outdoor sports, aerospace or military equipment.

[0029] Beneficial effects:

[0030] 1. The core layer of the fiber membrane of the present invention, which has both continuous cooling and moisture-regulating properties, has a phase-change property. The phase-change temperature is 28-32°C, which is close to the human body's comfortable temperature range (usually around 28°C). When the ambient temperature exceeds this phase-change temperature, the core layer absorbs heat through phase change, thereby reducing the temperature around the human body.

[0031] When the fiber comes into contact with the human body, the core layer is activated, absorbing the body's heat, lowering the body's core temperature and maintaining a comfortable microclimate;

[0032] When the ambient temperature rises or physical activity intensifies, the human body produces sweat vapor. The functional particles in the fiber absorb the sweat vapor. At the same time, the latent heat absorbed by the core layer drives the evaporation of water. The released water enhances the evaporative cooling effect, forming a self-sustaining positive feedback loop, which synergistically amplifies the overall cooling effect.

[0033] 2. The functional particles in the constituent fibers of the fiber membrane of the present invention having both continuous cooling and moisture regulating properties have a porous structure, a high specific surface area and adsorption properties, and can dynamically regulate the absorption and release of moisture. When the relative humidity of the environment is high, the fibers quickly absorb sweat vapor to reduce the feeling of stuffiness; when the environment is dry, the fibers gradually release the stored moisture to maintain the relative humidity regulation and stability of the microenvironment. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the sustained cooling and moisture regulation mechanism of the fiber membrane with both sustained cooling and moisture regulation properties of the present invention;

[0035] Figure 2 This is a TEM image of TMRT fiber (the gray circle area in the background of this image is the copper mesh structure used to support the sample during TEM sample preparation and is unavoidable);

[0036] Figure 3 These are the infrared contrast images of TMRT fiber membrane, PAC fiber membrane, PPEG fiber membrane, and PU fiber membrane in the skin simulation experiment; a is the physical layout diagram of each fiber membrane in its initial state, and b is the corresponding infrared thermal imaging image of each fiber membrane at 0 / 0.3 / 0.6 minutes;

[0037] Figure 4 This is the temperature comparison curve of simulated skin, TMRT fiber membrane, PAC fiber membrane, PPEG fiber membrane and PU fiber membrane in the skin simulation experiment from 0-20min;

[0038] Figure 5 The relative humidity-time comparison curves of the moisture regulation efficiency tests of TMRT fiber membrane, PAC fiber membrane, PPEG fiber membrane, and PU fiber membrane;

[0039] Figure 6This is the relative humidity-time comparison curve of TMRT fiber membrane and PET fabric in the moisture conditioning experiment;

[0040] Figure 7 This is a comparison curve of the cooling duration test between TMRT fiber membrane and PET fabric. DETAILED DESCRIPTION

[0041] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0042] The following are the test methods of the relevant performance indicators in each embodiment and comparative example and the specific process of the relevant experiments:

[0043] Melting point: tested according to GB / T 617-2006 "General method for determination of melting point range of chemical reagents".

[0044] Porosity: The porosity of functional particles is measured according to the standard GB / T19587-2017 "Determination of the specific surface area of ​​solid substances by gas adsorption BET method" using ASAP 2460 surface area analyzer and the porosity (P) is calculated according to the following formula:

[0045] P=Vp / Vt×100%;

[0046] Where Vp is the pore volume per unit mass of functional particles (unit: cm 3 / g), Vt is the total volume of functional particles per unit mass (in cm 3 / g).

[0047] Specific surface area: tested using an ASAP 2460 surface area analyzer in accordance with standard GB / T19587-2017 “Determination of the specific surface area of ​​solid substances by the gas adsorption BET method”.

[0048] Adsorption capacity of water vapor: First, place the functional particles in a vacuum oven at 60°C and dry them to constant weight (the weight at this time is m0, unit is g), then place them in a constant temperature and humidity chamber (temperature 25°C, relative humidity 90%) for 72 hours, take out the functional particles and weigh them (the weight at this time is m1, unit is g), and calculate the adsorption capacity of the functional particles for water vapor C according to the following formula abs (Unit: mg / g):

[0049] C abs = (m1-m0) × 10 3 / m0.

[0050] Phase transition temperature: measured by differential scanning calorimetry (DSC250).

[0051] Water vapor permeability: tested according to standard GB / T 12704.1-200 "Test method for water vapor permeability of textile fabrics - Part 1: Moisture absorption method".

[0052] Dry / wet breaking strength: tested according to standard GBT3923.1-2013 "Tensile properties of textile fabrics Part 1: Determination of breaking force and elongation at break (strip method)".

[0053] Q-max value: tested according to standard GB / T 35263-2017 "Testing and evaluation of the instantaneous cooling properties of textiles".

[0054] Duration of cool feeling: The test is conducted according to the standard T CNGA 23-2021 "Testing and evaluation of the continuous cooling performance of clothing", and the time corresponding to the temperature starting to rise and approaching 30°C is taken as the duration of the cool feeling; among which, the ambient temperature is 35°C and the relative humidity is 30%.

[0055] Moisture regulation efficiency: In an environment with a relative humidity of 31±1%, first prepare an acrylic box with a cubic structure (length 25cm, width 21cm, height 42cm). A switch door is set on the side of the box (to facilitate the insertion or removal of the fiber membrane). A square (5cm×5cm) through-hole is opened in the center of the top of the box. A humidifier (manufacturer: Xiaomi Technology Co., Ltd., model: MJJSQ02LX) is set at the through-hole. The steam outlet of the humidifier is facing the inside of the box. The initial temperature in the box is 23℃, and the initial relative humidity in the box ranges from 15-40% (within this range, the initial relative humidity in the box has no obvious effect on the test results, and any value can be selected). A hygrometer (for real-time monitoring of the relative humidity within the box, manufactured by China Medecine Co., Ltd., model JR900) was placed in a sealed state. A fiber membrane (25 cm long, 20 cm wide) was then laid flat on the bottom of the box. Six cycles of humidity adjustment were then performed continuously. The specific process for a single humidity adjustment cycle was as follows: water vapor was introduced into the box through the through-hole using a humidifier (operating at the first gear). One minute after the start of water vapor introduction (the start of water vapor introduction in each cycle was marked as 0 min), water vapor introduction was stopped, and equilibrium was continued for 9 minutes, completing one humidity adjustment cycle. The relative humidity within the box was recorded over time. After the cycle was completed, the adjustment efficiency at time i was calculated using the following formula:

[0056] υ i =(H i -Hi-k ) / {i-(ik)};

[0057] In the formula, i=1min,2min,3min...;k=1min;H i is the relative humidity in the box at time i, unit is %; H i-k is the relative humidity in the box at time ik, in units of %;υ i is the regulation efficiency at time i, in % / min;

[0058] In each cycle, 9 regulation efficiencies can be obtained. The maximum and minimum values ​​of all regulation efficiencies obtained after 6 cycles are taken as the upper and lower limits. All regulation efficiencies obtained after 6 cycles are summarized into a range value, which is the moisture regulation efficiency of the fiber membrane.

[0059] The test process was carried out in parallel 3 times, and the average value was taken as the final result.

[0060] Simulated skin experiment: First, prepare the simulated skin (made of JY370 silicone rubber produced by Omega Corporation of the United States, with a thickness of 1mm). Spray distilled water on the simulated skin (to simulate sweat, with a spray volume of 0.1mL / cm 2 ), a heater was installed at the bottom of the simulated skin, and insulating foam wrapped in aluminum foil was placed under the heater (to reduce heat loss from the bottom of the simulated skin); then, the fiber membrane was covered on the simulated skin, and the heater was turned on to heat the simulated skin. At the same time, a FOTRIC 310 infrared thermal imaging camera (manufactured by Shanghai Thermal Imaging Technology Co., Ltd.) was used to monitor the real-time temperature of the simulated skin and fiber membrane, and obtain the temperature-time curve of the simulated skin and fiber membrane within 0-20 minutes.

[0061] Humidity conditioning experiment: In an environment with a relative humidity of 31±1%, first prepare an acrylic box with a cubic structure (length 25cm, width 21cm, height 42cm). The box is equipped with a switch door on the side (to facilitate the insertion or removal of the fiber membrane). A square (5cm×5cm) through-hole is opened in the center of the top of the box. A humidifier (manufacturer: Xiaomi Technology Co., Ltd., model: MJJSQ02LX) is installed in the through-hole. The steam outlet of the humidifier is facing the inside of the box. A horizontally arranged partition divides the internal space of the box into two upper and lower chambers. The volumes of the upper and lower chambers are equal. The partition can be pulled out of the box. The initial temperature inside the box is 23°C. Then, the partition is pulled out first, and the fiber membrane / PET fabric (length 25 cm, width 20 cm) is spread flat on the bottom of the box. The partition is then inserted and the humidifier is started. After the relative humidity in the upper chamber reaches 35% / 60% / 90%, the partition is pulled out again, and the curve of the relative humidity in the box changing with time is recorded.

[0062] The weight of the fiber membranes with both continuous cooling and moisture regulating properties in the following embodiments is 43 g / m 2 , the thickness is 158μm.

[0063] Example 1

[0064] A method for preparing a fiber membrane having both continuous cooling and moisture regulating properties, comprising the following steps:

[0065] (1) Preparation of raw materials;

[0066] DMF (N,N-dimethylformamide);

[0067] PU: melting point is 60℃;

[0068] Functional particles: Nano activated carbon, pore size 10-30nm, porosity 90%, specific surface area 500m 2 / g, particle size is 0.1-0.5μm, and the adsorption capacity for water vapor is 200mg / g under the conditions of temperature of 25℃ and relative humidity of 90%;

[0069] PEG: The manufacturer is Shanghai Aladdin Reagent Co., Ltd., the product number is P103726, and the number average molecular weight is 800 g / mol;

[0070] (2) preparing the skin layer spinning solution and the core layer spinning solution respectively;

[0071] The cortex spinning solution consists of DMF, PU and functional particles. The mass ratio of PU to functional particles is 1:0.05, and the total concentration of cortex substrate and functional particles is 20wt%.

[0072] The core layer spinning solution consists of DMF, PEG and PU, with a mass ratio of PEG to PU of 1:2 and a total concentration of PEG and PU of 20 wt%;

[0073] (3) Preparation of fiber membranes with both continuous cooling and moisture regulation properties;

[0074] The skin layer spinning solution and the core layer spinning solution are coaxially electrospun to obtain a fiber membrane with both continuous cooling and moisture regulation properties;

[0075] The process parameters of coaxial electrospinning are as follows: injection rate of the skin spinning solution is 2 mL / h, injection rate of the core spinning solution is 0.3 mL / h, spinning voltage is 18 kV, spinning distance is 20 cm, ambient temperature is 20 °C, relative humidity is 30%, slide moving speed is 100 cm / min, and receiving roller speed is 50 r / min.

[0076] The final fiber membrane with both continuous cooling and moisture regulation properties (referred to as TMRT fiber, TEM Figure 2 The fiber membrane (shown as shown) consists of a skin layer and a core layer with a circular cross-section. The core layer has phase change properties with a phase change temperature of 28.7°C. The core layer has a diameter of 800nm ​​and a thickness of 200nm. The moisture permeability of the fiber membrane (denoted as TMRT fiber membrane) with both continuous cooling and moisture regulation properties is 10.14kg·m -2 ·d -1 The dry breaking strength is 5.88MPa, the wet breaking strength is 6.56MPa, the Q-max value is 0.43W / cm², the cooling sensation lasts for 60min, and the moisture regulation efficiency is 0.05-3% / min.

[0077] The TMRT fiber film and PET fabric (manufacturer: Quanzhou Senli Textile Trading Co., Ltd., item number 1308, weight 85g / m 2 ) to conduct humidity adjustment experiments, and the relative humidity-time change comparison curve is as follows Figure 6 As shown, from Figure 6 It can be seen that the moisture regulation efficiency of TMRT fiber membrane in various relative humidity environments is significantly better than that of PET fabric.

[0078] The comparison curve of the cooling duration test of TMRT fiber membrane and PET fabric is as follows Figure 7 As shown, from Figure 7 It can be seen that the surface temperature of the TMRT fiber membrane still maintained at 29.8℃ (<30℃) after 60 minutes, while the PET fabric exceeded 30℃ in only 22 minutes, indicating that the TMRT fiber membrane has good continuous cooling properties.

[0079] Comparative Example 1

[0080] A method for preparing a PAC fiber membrane differs from Example 1 only in that the PEG in the core layer spinning solution is replaced by PU of equal mass.

[0081] Comparative Example 2

[0082] A method for preparing a PPEG fiber membrane is different from that of Example 1 in that there are no functional particles in the cortex spinning solution.

[0083] Comparative Example 3

[0084] A method for preparing a PU fiber membrane is different from Example 1 only in that the skin layer spinning solution has no functional particles, and the core layer spinning solution is the same as the skin layer spinning solution.

[0085] The final products of Comparative Examples 1 to 3 are respectively recorded as PAC fiber membrane, PPEG fiber membrane, and PU fiber membrane. The simulated skin test is performed on TMRT fiber membrane, PAC fiber membrane, PPEG fiber membrane, and PU fiber membrane respectively. The results are as follows: Figure 3 and Figure 4 As shown; the relative humidity-time comparison curves of the moisture regulation efficiency test of TMRT fiber membrane, PAC fiber membrane, PPEG fiber membrane and PU fiber membrane are as shown Figure 5 As shown. Figures 3 to 5 It can be seen that the PAC fiber membrane, PPEG fiber membrane, and PU fiber membrane have significantly poorer inhibitory effects on simulated skin temperature rise and moisture regulation performance. This is because:

[0086] In PAC fiber membranes, the PEG in the core layer spinning solution is replaced by PU, resulting in the loss of the core layer's phase change properties. It can neither absorb heat through phase change nor provide an active cooling source when the temperature rises. Furthermore, the process of promoting water evaporation by the latent heat of phase change is missing, so moisture adsorption cannot be effectively converted into evaporative heat dissipation, leading to the accumulation of stuffiness. In PPEG fiber membranes, the lack of functional particles in the skin layer spinning solution prevents the rapid adsorption of simulated sweat vapor when the human body sweats. Simulated sweat accumulates on the skin surface and hinders the evaporative cooling effect. Simultaneously, the lack of adsorption by functional particles prevents the latent heat released by the core layer's phase change from amplifying the cooling effect through the "adsorption-evaporation" cycle, resulting in a poorer suppression of the simulated skin temperature rise. In PU fiber membranes, the lack of functional particles in the skin layer and the absence of PEG in the core layer results in the loss of both the "moisture adsorption" and "phase change cooling" mechanisms. For moisture regulation, the functional particles cannot adsorb simulated sweat vapor, nor can the phase change latent heat promote water evaporation. This leads to an imbalance in environmental humidity and an inability to effectively transfer heat.

[0087] Comparative Example 4

[0088] A method for preparing a fiber membrane, which differs from Example 1 only in that the functional particles are nano-alumina; the pore size of the nano-alumina is 10-30nm, the porosity is 90%, and the specific surface area is 500m 2 / g, particle size is 0.1-0.5μm.

[0089] The cooling effect of the fiber membrane finally prepared lasts for 10 minutes, and the moisture regulation efficiency is 0-0.05% / min.

[0090] Comparative Example 5

[0091] A method for preparing a fiber membrane, which differs from Example 1 only in that the functional particles are nano zinc oxide; the pore size of the nano zinc oxide is 10-30nm, the porosity is 90%, and the specific surface area is 500m 2 / g, particle size is 0.1-0.5μm.

[0092] The cooling effect of the fiber membrane finally prepared lasts for 5 minutes, and the moisture regulation efficiency is 0-0.05% / min.

[0093] Compared to Example 1, the fiber membranes produced in Comparative Examples 4 and 5 exhibited significantly poorer cooling duration and moisture regulation efficiency. This is because the functional particles used in Comparative Examples 4 and 5 lack the ability to absorb sweat vapor, preventing them from promptly removing moisture and heat from the skin's surface. This leads to sweat accumulation on the skin's surface, hindering the evaporative cooling effect. Furthermore, due to the lack of active sweat vapor adsorption, the heat and moisture exchange efficiency within the fibers is low, preventing evaporation from promptly removing body heat, leading to a decrease in their sustained cooling performance and moisture regulation performance.

[0094] Example 2

[0095] A method for preparing a fiber membrane having both continuous cooling and moisture regulating properties, comprising the following steps:

[0096] (1) Preparation of raw materials;

[0097] DMF (N,N-dimethylformamide);

[0098] PU: melting point is 60℃;

[0099] Functional particles: Nano activated carbon, pore size 20-50nm, porosity 92%, specific surface area 900m 2 / g, particle size is 0.3-1μm, and the adsorption capacity for water vapor is 300mg / g under the conditions of temperature of 25℃ and relative humidity of 90%;

[0100] PEG: The manufacturer is Shanghai Aladdin Reagent Co., Ltd., the product number is P103726, and the number average molecular weight is 800 g / mol;

[0101] (2) preparing the skin layer spinning solution and the core layer spinning solution respectively;

[0102] The cortex spinning solution consists of DMF, PU and functional particles. The mass ratio of PU to functional particles is 1:0.1, and the total concentration of cortex substrate and functional particles is 20wt%.

[0103] The core layer spinning solution consists of DMF, PEG and PU, with a mass ratio of PEG to PU of 1:5 and a total concentration of PEG and PU of 20 wt%;

[0104] (3) Preparation of fiber membranes with both continuous cooling and moisture regulation properties;

[0105] The skin layer spinning solution and the core layer spinning solution are coaxially electrospun to obtain a fiber membrane with both continuous cooling and moisture regulation properties;

[0106] The process parameters of coaxial electrospinning were as follows: injection rate of the skin spinning solution was 3 mL / h, injection rate of the core spinning solution was 1 mL / h, spinning voltage was 20 kV, spinning distance was 20 cm, ambient temperature was 25 °C, relative humidity was 50%, slide moving speed was 70 cm / min, and receiving roller speed was 50 r / min.

[0107] The fiber membrane with both continuous cooling and moisture regulation properties is composed of a cortex and a core layer with a circular cross-section. The core layer has phase change properties with a phase change temperature of 30°C. The core layer has a diameter of 1000nm and a thickness of 100nm. The moisture permeability of the fiber membrane with both continuous cooling and moisture regulation properties is 8.15kg·m -2 ·d -1 The dry breaking strength is 5.27MPa, the wet breaking strength is 2.61MPa, the Q-max value is 0.38W / cm², the cooling sensation lasts for 45min, and the moisture regulation efficiency is 0.01-1% / min.

[0108] Example 3

[0109] A method for preparing a fiber membrane having both continuous cooling and moisture regulating properties, comprising the following steps:

[0110] (1) Preparation of raw materials;

[0111] DMF (N,N-dimethylformamide);

[0112] PU: melting point is 80℃;

[0113] Functional particles: Nano activated carbon, pore size 20-50nm, porosity 95%, specific surface area 1200m 2 / g, particle size is 0.3-1.2μm, and the adsorption capacity for water vapor is 200mg / g under the conditions of temperature of 25℃ and relative humidity of 90%;

[0114] PEG: The manufacturer is Shanghai Aladdin Reagent Co., Ltd., the product number is P103727, and the number average molecular weight is 600 g / mol;

[0115] (2) preparing the skin layer spinning solution and the core layer spinning solution respectively;

[0116] The cortex spinning solution consists of DMF, PU and functional particles. The mass ratio of PU to functional particles is 1:0.3, and the total concentration of cortex substrate and functional particles is 20wt%.

[0117] The core layer spinning solution consists of DMF, PEG and PU, with a mass ratio of PEG to PU of 1:3 and a total concentration of PEG and PU of 20 wt%;

[0118] (3) Preparation of fiber membranes with both continuous cooling and moisture regulation properties;

[0119] The skin layer spinning solution and the core layer spinning solution are coaxially electrospun to obtain a fiber membrane with both continuous cooling and moisture regulation properties;

[0120] The process parameters of coaxial electrospinning are as follows: injection rate of the skin spinning solution is 4 mL / h, injection rate of the core spinning solution is 1.3 mL / h, spinning voltage is 18 kV, spinning distance is 25 cm, ambient temperature is 30 °C, relative humidity is 50%, slide moving speed is 100 cm / min, and receiving roller speed is 100 r / min.

[0121] The resulting fiber membrane, which has both sustained cooling and moisture-regulating properties, consists of a cortex and a core layer. The cross-section is circular, and the core layer has phase-change properties at a temperature of 31°C. The core layer has a diameter of 900 nm and a cortex thickness of 300 nm. The moisture permeability of the fiber membrane, which has both sustained cooling and moisture-regulating properties, is 9.61 kg·m -2 ·d -1 The dry breaking strength is 4.48MPa, the wet breaking strength is 8.47MPa, the Q-max value is 0.33W / cm², the cooling sensation lasts for 50min, and the moisture regulation efficiency is 0.01-1.5% / min.

[0122] Example 4

[0123] A method for preparing a fiber membrane having both continuous cooling and moisture regulating properties, comprising the following steps:

[0124] (1) Preparation of raw materials;

[0125] DMF (N,N-dimethylformamide);

[0126] PU: melting point is 100℃;

[0127] Functional particles: Nano activated carbon, pore size 70-100nm, porosity 95%, specific surface area 1500m 2 / g, particle size is 1.5-2μm, and the adsorption capacity for water vapor is 250mg / g under the conditions of temperature of 25℃ and relative humidity of 90%;

[0128] PEG: The manufacturer is Shanghai Aladdin Reagent Co., Ltd., the product number is P103737, and the number average molecular weight is 400 g / mol;

[0129] (2) preparing the skin layer spinning solution and the core layer spinning solution respectively;

[0130] The cortex spinning solution consists of DMF, PU and functional particles. The mass ratio of PU to functional particles is 1:0.5, and the total concentration of cortex substrate and functional particles is 20wt%.

[0131] The core layer spinning solution consists of DMF, PEG and PU, with a mass ratio of PEG to PU of 1:0.5 and a total concentration of PEG and PU of 20 wt%;

[0132] (3) Preparation of fiber membranes with both continuous cooling and moisture regulation properties;

[0133] The skin layer spinning solution and the core layer spinning solution are coaxially electrospun to obtain a fiber membrane with both continuous cooling and moisture regulation properties;

[0134] The process parameters of coaxial electrospinning are as follows: injection rate of the skin spinning solution is 5 mL / h, injection rate of the core spinning solution is 1.5 mL / h, spinning voltage is 22 kV, spinning distance is 30 cm, ambient temperature is 25 °C, relative humidity is 70%, slide moving speed is 50 cm / min, and receiving roller speed is 75 rpm.

[0135] The fiber membrane with both continuous cooling and moisture regulation properties is composed of a cortex and a core layer. The cross-section is circular, and the core layer has phase change properties with a phase change temperature of 32°C. The core layer has a diameter of 500nm and a thickness of 500nm. The moisture permeability of the fiber membrane with both continuous cooling and moisture regulation properties is 9.96kg·m -2 ·d -1 The dry breaking strength is 3.47MPa, the wet breaking strength is 2.61MPa, the Q-max value is 0.28W / cm², the cooling sensation lasts for 55min, and the moisture regulation efficiency is 0.02-2% / min.

[0136] The present invention prepares a fiber membrane with both continuous cooling and moisture regulation properties through coaxial electrospinning. The cooling sensation lasts for 45-60 minutes, and the moisture regulation efficiency reaches 0.01-2% / min. This functionality enables it to resist heat accumulation in high-temperature environments in the field of personal protection, adapt to changing climates and maintain wearing comfort during outdoor sports, meet the lightweight thermal regulation needs under extreme temperatures in the aerospace field, and take into account both protective functions and microclimate management in complex environments in military equipment scenarios.

Claims

1. A fiber membrane with both sustained cooling and moisture regulation properties, wherein the constituent fibers have a skin-core structure, the skin layer comprises a skin substrate and functional particles, and the core layer has phase change properties, characterized in that: Functional particles have the property of absorbing sweat vapor; the phase transition temperature of the core layer is 28-32°C; the functional particles are activated carbon; the pore size of the functional particles is 10-100nm, the porosity is ≥85%, and the specific surface area is 500-1500m 2 / g, with a particle size of 0.1-2μm and a water vapor adsorption capacity of ≥200mg / g at a temperature of 25°C and a relative humidity of 90%. The core layer is a blend of PEG and PU in a mass ratio of 1:0.5-5, with a number-average molecular weight of PEG ≤800g / mol and a melting point of PU of 60-100°C. The fiber membrane, which has both continuous cooling and moisture-regulating properties, has a water vapor permeability of 8.15-10.14kg·m -2 ·d -1 The cooling sensation lasts for 45-60 minutes.

2. A fiber membrane with both continuous cooling and moisture regulating properties according to claim 1, characterized in that: The base material of the cortex is PU.

3. The fiber membrane having both continuous cooling and moisture regulating properties according to claim 1, characterized in that: The mass ratio of the cortical substrate to the functional particles is 1:0.05-0.

5.

4. The fiber membrane having both continuous cooling and moisture regulating properties according to claim 1, characterized in that: The cross section of its constituent fibers is circular, the diameter of the core layer is 500-1000nm, and the thickness of the skin layer is 100-500nm.

5. A fiber membrane having both continuous cooling and moisture regulating properties according to any one of claims 1 to 4, characterized in that: The fiber membrane, which has both continuous cooling and moisture regulation properties, has a dry breaking strength of 3.47-5.88 MPa, a wet breaking strength of 2.61-8.47 MPa, and a Q-max value of 0.28-0.43 W / cm².

6. A method for preparing a fiber membrane having both sustained cooling and moisture regulating properties as claimed in any one of claims 1 to 5, characterized in that: After respectively preparing the skin layer spinning solution and the core layer spinning solution, coaxial electrospinning is performed to obtain a fiber membrane with both continuous cooling and moisture regulating properties.

7. The method according to claim 6, characterized in that: The process parameters of coaxial electrospinning include: injection rate of skin spinning solution 2-5 mL / h, injection rate of core spinning solution 0.3-1.5 mL / h, spinning voltage 18-22 kV, spinning distance 20-30 cm, ambient temperature 20-30 ° C, ambient relative humidity 30-70%, slide moving speed 50-100 cm / min, and receiving roller speed 50-100 r / min.

8. An application of the fiber membrane having both continuous cooling and moisture regulating properties as claimed in any one of claims 1 to 5, characterized in that: Used for personal protection, outdoor sports, aerospace or military equipment.

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