Multifunctional coaxial composite fiber, preparation method and application thereof

Abstract

The present invention discloses a multifunctional coaxial composite fiber, a preparation method and application thereof. The multifunctional coaxial composite fiber comprises a coaxially arranged fiber core and a sheath; the fiber core comprises a composite of a hydrophilic polymer, gelatin and silica nanoparticles; the sheath comprises a composite of a hydrophilic polymer, a non-metallic conductive material and metal nanowires. The multifunctional coaxial composite fiber provided by the present invention has multiple functions of electrothermal effect, humidity perception and self-sensing drive. The coaxial fiber is water-absorbent and has humidity-size responsiveness. The electrothermal function assists in the rapid desorption of water molecules, improves the drive response rate, and accelerates the contraction of the fiber to achieve rapid physical closure of the wound; it can monitor changes in wound humidity, sense wound exudate, and remind and quickly adjust the contraction state of the wound. It can provide applications in the direction of wound healing and monitoring, and can achieve very excellent wound monitoring and healing promotion effects.

Description

Technical Field

[0001] The present invention relates to the field of fiber material science and technology, and in particular to a multifunctional coaxial composite fiber, a preparation method and application thereof. Background Art

[0002] Fibers, as one of the important basic necessities in human daily life, can be made into functional textiles by winding, weaving, knotting or bonding together. With the development of society, fibers are no longer limited to being woven into fabrics to provide warmth. Smart fibers are playing an increasingly important role in human daily life. In particular, integrating advanced synergistic effects into a tiny fiber puts higher demands on the development of smart fibers. The materials used to prepare smart fibers are diverse, including but not limited to inorganic non-metallic materials, metallic materials and synthetic polymers. Smart fibers provide lightweight and flexible solutions for applications such as artificial muscles, sensors, heaters, friction nanogenerators, thermal regulation textiles, electronic skin and implantable devices.

[0003] Advances in fiber fabrication technology have opened new opportunities for developing functional textiles with complex sensing and actuation capabilities, making them highly attractive for a range of applications. Ma et al. developed a fiber-based humidity sensor based on a biaxial yarn-wrapped structure. This sensor, woven into a 3M mask, can monitor human respiration in real time, potentially helping to assess health in daily life. Recently, Nam et al. implanted an artificial muscle fiber into the thigh of a mouse, demonstrating for the first time the functional replacement of natural muscle tissue. This approach offers promising applications in implantable medicine and the treatment of muscle atrophy. However, the lack of intelligence inherent in these single-function fibers limits their application in complex scenarios. Regarding the multifunctional integration of smart fibers, Ning et al. developed a dual-mode smart fiber with self-powered pressure sensing and temperature regulation of the microenvironment surrounding human skin, using hollow silicone rubber fibers filled with liquid metal electrodes. This fiber shows great promise for real-time thermal regulation and personal motion monitoring. Marriam et al. developed a conductive fiber coated with electroactive carbon black that has both energy storage and volatile organic compound monitoring capabilities. Despite significant progress in developing multifunctional smart fibers, it is noteworthy that advanced synergistic applications between the various fiber functions remain lacking.

[0004] Specifically, although other smart fibers have achieved multiple functions on the same fiber, there is a lack of close synergy between the functions; there are still great challenges in the mass production of multifunctional smart fibers; there are currently few reports on designs that integrate the three functions of perception, drive and feedback on the same fiber. Most of them are based on separate designs of each functional unit, which is not suitable for some miniaturized and intelligent application scenarios. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention aims to provide a multifunctional coaxial composite fiber, a preparation method and application thereof.

[0006] To achieve the aforementioned object of the invention, the technical solutions adopted by the present invention include:

[0007] In a first aspect, the present invention provides a multifunctional coaxial composite fiber comprising a coaxially arranged fiber core and a sheath;

[0008] The fiber core includes a composite of a hydrophilic polymer, gelatin, and silica nanoparticles;

[0009] The sheath layer includes a composite of a hydrophilic polymer, a non-metallic conductive material and metal nanowires.

[0010] In a second aspect, the present invention further provides a method for preparing a multifunctional coaxial composite fiber, comprising:

[0011] Providing a first spinning solution and a second spinning solution, wherein the first spinning solution contains a hydrophilic polymer, gelatin, and silica nanoparticles, and the second spinning solution contains a hydrophilic polymer, a non-metallic conductive material, and metal nanowires;

[0012] Allowing the first spinning solution to enter a coagulation bath through a first spinning channel and the second spinning solution to enter a coagulation bath through a second spinning channel to obtain a precursor coaxial fiber, wherein the second spinning channel is coaxially arranged around the first spinning channel;

[0013] The precursor coaxial fiber is dried to obtain a multifunctional coaxial composite fiber.

[0014] In a third aspect, the present invention further provides use of the multifunctional coaxial composite fiber in the preparation of a medical product, wherein the medical product has at least one of the functions of monitoring wound changes, promoting wound healing, and thermal therapy;

[0015] Furthermore, as an application for promoting wound healing, the medical product obtains changes in wound exudate by detecting changes in the resistance of the multifunctional coaxial composite fiber;

[0016] Furthermore, when the medical product detects that the resistance change of the multifunctional coaxial composite fiber exceeds a preset threshold, an electric current is applied to the multifunctional coaxial composite fiber to promote the desorption of the exudate adsorbed by the multifunctional coaxial composite fiber and to cause the multifunctional coaxial composite fiber to shrink;

[0017] Furthermore, when the multifunctional coaxial composite fiber contracts, the medical product continues to monitor the contraction of the multifunctional coaxial composite fiber by monitoring the change in resistance.

[0018] In a fourth aspect, the present invention further provides a wound healing dressing comprising the multifunctional coaxial composite fiber;

[0019] Furthermore, electrodes are provided at both ends of the multifunctional coaxial composite fiber.

[0020] In a fifth aspect, the present invention further provides a method for using the multifunctional coaxial composite fiber, comprising: adjusting the moisture content of the multifunctional coaxial composite fiber to change at least one physical property of the multifunctional coaxial composite fiber, the physical property comprising one or more of length, diameter, and electrical resistance;

[0021] Furthermore, the method specifically includes: passing current into the multifunctional coaxial composite fiber to adjust the water content of the multifunctional coaxial composite fiber through electrothermal effect.

[0022] In a sixth aspect, the present invention further provides a wound monitoring and treatment device, comprising:

[0023] The multifunctional coaxial composite fiber is used to be placed on the wound and its two ends are fixedly connected to the skin on both sides of the wound;

[0024] a monitoring module, electrically connected to the multifunctional coaxial composite fiber, and at least used to monitor the resistance of the multifunctional coaxial composite fiber;

[0025] a control module electrically connected to the monitoring module and configured to adjust the current input to the multifunctional coaxial composite fiber based on a monitoring signal output by the monitoring module, thereby adjusting the moisture content of the multifunctional coaxial composite fiber and thereby changing at least the length of the multifunctional coaxial composite fiber;

[0026] Furthermore, it also includes an alarm module, which is connected to the monitoring module and / or the control module and is used to issue an alarm message when the monitoring module detects that the resistance of the multifunctional coaxial composite fiber reaches a set threshold.

[0027] Based on the above technical solution, compared with the prior art, the beneficial effects of the present invention include at least:

[0028] The multifunctional coaxial composite fiber provided by the present invention has multifunctional synergistic coaxial composite fibers with electrothermal effect, humidity sensing and self-sensing drive. The integrated preparation method saves costs and can realize batch preparation.

[0029] Furthermore, the various functions of the coaxial fiber are not independent and superimposed, but rather work in synergy. The electrothermal and drive functions work synergistically, exhibiting water absorption and humidity-size responsiveness. The electrothermal function also assists in the rapid desorption of water molecules, improving the drive response rate. The humidity sensing function and the electrothermal-assisted drive function work synergistically, allowing the coaxial fiber to monitor changes in wound humidity and sense wound exudate, then issue reminders in various ways and quickly adjust the wound's contraction state.

[0030] The multifunctional coaxial composite fiber provided by the present invention has clear application directions and can be applied in the direction of wound healing and monitoring, and can achieve very excellent wound monitoring and healing promotion effects.

[0031] The above description is only an overview of the technical solution of the present invention. In order to enable those skilled in the art to more clearly understand the technical means of this application and implement them according to the contents of the specification, the following is an explanation of the preferred embodiments of the present invention with detailed drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the preparation process of a multifunctional coaxial composite fiber provided by a typical embodiment of the present invention;

[0033] Figure 2a This is a low-magnification electron microscope photograph of the surface morphology of a multifunctional coaxial composite fiber provided in a typical embodiment of the present invention;

[0034] Figure 2b This is a high-magnification electron microscope photograph of the surface morphology of a multifunctional coaxial composite fiber provided in a typical embodiment of the present invention;

[0035] Figure 2c This is a photograph of the change in the water adsorption state of the multifunctional coaxial composite fiber provided in a typical embodiment of the present invention;

[0036] Figure 2d This is a low-magnification electron microscope photograph of the radial cross-section of a multifunctional coaxial composite fiber provided in a typical embodiment of the present invention;

[0037] Figure 2e This is a high-magnification electron microscope photograph of the radial cross-section of a multifunctional coaxial composite fiber provided in a typical embodiment of the present invention;

[0038] Figure 2f This is a test diagram of radial cross-section element distribution of a multifunctional coaxial composite fiber provided by a typical embodiment of the present invention;

[0039] Figure 2g This is a MAP diagram of the radial cross-section element distribution of a multifunctional coaxial composite fiber provided by a typical embodiment of the present invention;

[0040] Figure 3 This is a test diagram of the electrothermal-assisted rapid driving performance of the multifunctional coaxial composite fiber provided by a typical embodiment of the present invention;

[0041] Figure 4a This is a test diagram of the humidity sensing function of the multifunctional coaxial composite fiber provided by a typical embodiment of the present invention;

[0042] Figure 4b This is a self-sensing performance test diagram of a multifunctional coaxial composite fiber provided by a typical embodiment of the present invention;

[0043] Figure 5a This is a schematic diagram of the wound healing effect of a wound healing dressing provided by a typical embodiment of the present invention;

[0044] Figure 5b This is an example diagram of a wound monitoring method for a wound healing dressing provided in a typical embodiment of the present invention;

[0045] Figure 5c This is a photograph of the wound healing process of a wound healing dressing provided by a typical embodiment of the present invention;

[0046] Figure 5d This is a detailed photo of the wound healing process of a wound healing dressing provided in a typical embodiment of the present invention. DETAILED DESCRIPTION

[0047] In view of the shortcomings of the prior art, the inventors of this case, after long-term research and extensive practice, have proposed the technical solution of the present invention. The following will further explain this technical solution, its implementation process and principles.

[0048] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0049] Moreover, relational terms such as “first” and “second” are merely used to distinguish one component or method step from another with the same name, but do not necessarily require or imply any actual relationship or order between these components or method steps.

[0050] An embodiment of the present invention provides a multifunctional coaxial composite fiber, which includes a coaxially arranged fiber core and a sheath; the fiber core includes a composite of a hydrophilic polymer, gelatin and silica nanoparticles; the sheath includes a composite of a hydrophilic polymer, a non-metallic conductive material and metal nanowires.

[0051] Regarding the selection of hydrophilic polymers for the fiber core and sheath, it's important to note that while both are named "hydrophilic polymer," they represent a class of compounds and do not necessarily require the same specific material for each component. For example, sodium alginate can be used for the fiber core, while chitosan can be used for the sheath. Regarding the molecular weight of the hydrophilic polymer, commonly used materials and parameters for liquid-phase spinning methods can be used.

[0052] Regarding the specific composite structure, in the fiber core, hydrophilic polymers such as sodium alginate and gelatin molecular chains form a double network structure that locks the nano-silica particles (which can be understood as the silica nanoparticles embedded in the gaps of the double network structure); non-metallic conductive materials such as MXene or carbon-based conductive materials and metal nanowires belong to a three-dimensional conductive network composed of wires and sheets, and the hydrophilic polymer is evenly dispersed around the conductive network, making it difficult for the conductive material to settle and acting as a cross-linking substance with the coagulation bath to lock the conductive material to the fiber surface. As a result, the sheath can sense changes in humidity and can also act as a heating layer to accelerate the rapid desorption of water molecules, allowing the fiber to complete the rapid drive process. The contraction rate of the fiber can be controlled by different applied voltages.

[0053] It should also be noted that in the present invention, non-metallic conductive materials and metal nanowires need to be combined and synergistically composited. Simply using one non-metallic conductive material or only metal nanowires cannot achieve good technical effects and will affect the performance of the coaxial fiber in many aspects, as shown in the following examples.

[0054] In some embodiments, the hydrophilic polymer includes any one of sodium alginate, chitosan, and cellulose, or a combination of two or more thereof.

[0055] In some embodiments, the non-metallic conductive material includes any one of MXene, graphene, and carbon nanotubes, or a combination of two or more thereof.

[0056] In some embodiments, the metal nanowires include any one of copper nanowires, silver nanowires, and gold nanowires, or a combination of two or more thereof.

[0057] In some embodiments, the metal nanowires may have a length of 6-22 μm and a diameter of 20-120 nm.

[0058] In some embodiments, the mass ratio of the hydrophilic polymer, gelatin, and silica nanoparticles in the fiber core is 3-7:3-7:0.5-2.5.

[0059] In some embodiments, the mass ratio of the hydrophilic polymer, the non-metallic conductive material, and the metal nanowires in the sheath layer is 8-12:1-3:4-6.

[0060] In some embodiments, the fiber core has a diameter of 100-400 μm.

[0061] In some embodiments, the sheath layer has a thickness of 10-50 μm.

[0062] As some typical application examples of the above technical solutions, the core of the multifunctional coaxial composite fiber can be composed of biopolymer-based materials, including sodium alginate, gelatin and silica nanoparticles; the sheath is composed of conductive-based materials, such as MXene, silver nanowires and sodium alginate.

[0063] In some embodiments, the multifunctional coaxial composite fiber is capable of absorbing water; at least one physical property of the multifunctional coaxial composite fiber changes with the water content of the multifunctional coaxial composite fiber, the physical property including one or more of length, diameter, and electrical resistance; the water content of the multifunctional coaxial composite fiber changes after an electric current is passed through the multifunctional coaxial composite fiber, the electric current being used to cause the multifunctional coaxial composite fiber to produce an electrothermal effect; and the electrical resistance of the multifunctional coaxial composite fiber changes with either the length or diameter of the multifunctional coaxial composite fiber. In other words, when the water content of the multifunctional coaxial composite fiber changes, the length and / or diameter and electrical resistance of the multifunctional coaxial composite fiber also change; and when an electric current is applied to the multifunctional coaxial composite fiber, the electric current can accelerate the desorption of water from the multifunctional coaxial composite fiber and the shrinkage of the multifunctional coaxial composite fiber.

[0064] like Figure 1 As shown, an embodiment of the present invention further provides a method for preparing a multifunctional coaxial composite fiber, which comprises the following steps:

[0065] A first spinning solution and a second spinning solution are provided, wherein a hydrophilic polymer, gelatin and silica nanoparticles are dispersed in the first spinning solution, and a hydrophilic polymer, a non-metallic conductive material and metal nanowires are dispersed in the second spinning solution.

[0066] The first spinning solution enters a coagulation bath through a first spinning channel, and the second spinning solution enters a coagulation bath through a second spinning channel to obtain a precursor coaxial fiber, wherein the second spinning channel is coaxially arranged around the first spinning channel.

[0067] The precursor coaxial fiber is dried to obtain a multifunctional coaxial composite fiber.

[0068] In some embodiments, the preparation method further comprises:

[0069] After the precursor coaxial fiber is dried, the dried fiber is brought into contact with the dispersion of the non-metallic conductive material and then dried again to finally obtain the multifunctional coaxial composite fiber.

[0070] In some embodiments, the mass fraction of the non-metallic conductive material in the dispersion is 1-3%.

[0071] In some embodiments, the mass fraction of the hydrophilic polymer in the first spinning solution is 1.5-3.5%, the mass fraction of gelatin is 1.5-3.5%, and the mass fraction of the silica nanoparticles is 0.25-1.25%.

[0072] In some embodiments, the mass fraction of the hydrophilic polymer in the second spinning solution is 0.4-0.6%, the mass fraction of the non-metallic conductive material is 1-3%, and the mass fraction of the metal nanowires is 4-6%.

[0073] In some embodiments, the first spinning solution is prepared by:

[0074] The gelatin is first dissolved in water at a temperature above 60° C. to obtain a gelatin solution. When the temperature is lowered to 15-35° C., the hydrophilic polymer and the silicon dioxide nanoparticles are dissolved in the gelatin solution.

[0075] As some typical application examples of the above technical solutions, for example, multifunctional coaxial composite fibers with multifunctional synergistic effects can be prepared by wet spinning. The specific preparation steps are as follows: Figure 1 As shown:

[0076] Step 1: Prepare a 5wt% calcium chloride aqueous solution coagulation bath. To prepare the core spinning solution, 2.5wt% gelatin particles are first dissolved in 60°C warm water. After the solution cools to room temperature, 2.5wt% sodium alginate and 1wt% silica nanoparticles are dissolved in the solution. Mechanical stirring is then used to form a uniform spinning solution. Finally, prolonged ultrasound is used to remove air bubbles from the spinning solution. The sheath spinning solution consists of 20mg / ml MXene, 5mg / ml silver nanowires, and 0.5wt% sodium alginate. Mechanical stirring is then used to form a uniform solution.

[0077] Step 2: Coaxial fibers were obtained by injecting the spinning solution into a calcium chloride coagulation bath at a constant extrusion speed. The coaxial needles were 25G inner and 18G outer. The wet-spun fibers were air-dried, then impregnated with a 20mg / mg MXene solution and dried again to prevent oxidation of the silver nanowires on the fiber surface due to exposure to air. Finally, the coaxial fibers were stored in darkness under argon.

[0078] Of course, if metal nanowires that are not susceptible to oxidation are used, the above-mentioned re-wetting and drying steps may not be performed, and the nanowires do not need to be stored in a dark and protective atmosphere.

[0079] Therefore, in the present invention, a multifunctional coaxial composite fiber is developed by a coaxial wet spinning method, specifically a sodium alginate / gelatin@MXene / silver nanowire composite fiber, which realizes the multiple roles of multiple sensing and driving functions. The bio-based polymer fiber core has a humidity-responsive deformation function, while the conductive sheath can realize electrothermal, humidity sensing and self-sensing driving functions. It is worth noting that the above-mentioned electrothermal function promotes the rapid desorption of water molecules, thereby improving the efficiency of the swollen fiber to return to its original length, and the desorption and contraction rate of the fiber can be regulated by controlling the current; the self-sensing function can provide real-time feedback on the working position status of the coaxial fiber. Due to the excellent multifunctional synergistic effect, this coaxial fiber shows the application potential in the integration of thermal therapy and wound healing / monitoring functions.

[0080] Although some existing technologies also disclose a technical solution in which a fiber has multiple functions, there are significant differences in principle between the present invention and the existing technology. This is mainly reflected in the fact that the present invention utilizes the conductive properties of the sheath and the hygroscopic properties of the fiber to achieve humidity response and motion perception based on humidity (water content) and electrothermal driving effects, and thus realizes the advantageous application of wound monitoring; while the capacitive sensing and the driving method utilizing the difference in expansion coefficient in the existing technology are essentially different from the present invention, and cannot realize the application function of wound monitoring.

[0081] The embodiments of the present invention further provide use of the multifunctional coaxial composite fiber provided by any of the above embodiments in preparing a wound healing dressing and / or promoting wound healing.

[0082] In some embodiments, changes in wound exudate are obtained by detecting changes in the resistance of the multifunctional coaxial composite fiber.

[0083] In some embodiments, when it is detected that the resistance change of the multifunctional coaxial composite fiber exceeds a preset threshold, an electric current can be applied to the multifunctional coaxial composite fiber to promote the desorption of the exudate adsorbed by the multifunctional coaxial composite fiber and cause the multifunctional coaxial composite fiber to shrink.

[0084] In some embodiments, when the multifunctional coaxial composite fiber shrinks, the shrinkage of the multifunctional coaxial composite fiber can be monitored by continuously monitoring the resistance change.

[0085] Correspondingly, an embodiment of the present invention further provides a wound healing dressing, which includes the multifunctional coaxial composite fiber provided by any of the above embodiments.

[0086] In some embodiments, electrodes are provided at both ends of the multifunctional coaxial composite fiber, and the electrodes are used at least to monitor the resistance change of the multifunctional coaxial composite fiber and / or apply current to the multifunctional coaxial composite fiber.

[0087] Of course, based on the above ideas, those skilled in the art can fully adaptably construct corresponding monitoring, power-on and alarm circuits and equipment based on existing common knowledge of electronics and control, which will not be elaborated here.

[0088] In summary, the electrothermal function of the multifunctional coaxial composite fiber provided by the present invention can promote the rapid desorption of water molecules, thereby improving the efficiency of the swollen fiber to recover to its original length; the humidity sensing function and the electrothermal assisted driving function work together to enable the coaxial fiber to monitor the humidity changes of the wound, and then quickly adjust the contraction state of the wound according to the prompts of the back-end circuit design; the coaxial fiber has self-sensing performance when it stretches in response to humidity changes, and the relative resistance of the coaxial fiber changes with the deformation of the fiber. By utilizing this phenomenon, the length changes of the fiber can be tracked at all times during the driving process without the need for a distance sensor.

[0089] The technical solution of the present invention is further described in detail below through several embodiments and in conjunction with the accompanying drawings. However, the selected embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0090] Example 1

[0091] This embodiment is a preparation process of a multifunctional coaxial composite fiber, which is specifically as follows:

[0092] Step 1: Prepare a 5wt% calcium chloride aqueous solution coagulation bath; To prepare the first spinning solution for the fiber core, dissolve 2.5wt% gelatin particles in 60°C warm water. Once the solution cools to room temperature (typically between 15-35°C, optimally 25°C), dissolve 2.5wt% sodium alginate and 1wt% silica nanoparticles. Mechanical stirring is then used to form a uniform first spinning solution. Finally, prolonged ultrasound is used to remove air bubbles from the spinning solution. The second spinning solution, which forms the sheath, consists of 20mg / ml MXene, 5mg / ml silver nanowires, and 0.5wt% sodium alginate. The spinning solution is mechanically stirred to form a uniform dispersion.

[0093] Step 2: Coaxial fibers were obtained by injecting the spinning solution into a calcium chloride coagulation bath at a constant extrusion speed. The coaxial needles were 25G inner and 18G outer. The wet-spun fibers were air-dried, then impregnated with a 20mg / mg MXene solution and dried again to prevent oxidation of the silver nanowires on the fiber surface due to exposure to air. Finally, the coaxial fibers were stored in darkness under argon.

[0094] Figure 2a This is a surface morphology of the multifunctional coaxial fiber prepared in this example. The diameter of the fiber is about 200 μm and the sheath layer on the surface can be seen. Figure 2b This is an enlarged view of the surface morphology of the multifunctional coaxial fiber. From the picture, it can be seen that MXene is very evenly wrapped on the fiber surface. Figure 2c These are optical images of the multifunctional coaxial fiber before and after reversible swelling in water. After swelling, the fiber increases to about 300 μm. Figure 2d-Figure 2e This is a cross-sectional view of the multifunctional coaxial fiber. The coaxial structure of the fiber can be clearly seen from the figure. Figure 2f-2g The element distribution test of the sheath and core shaft found that the element distribution was very clear under the Mapping analysis, with Ti and Ag elements distributed in the sheath, and Na and Si elements distributed in the core shaft.

[0095] Figure 3 This is the electrothermal assisted rapid driving performance diagram of the multifunctional coaxial fiber. It can be seen that the multifunctional coaxial fiber is sensitive to humidity and can adsorb water molecules to achieve elongation through swelling. After the water molecules are desorbed, the multifunctional coaxial fiber can restore its original shape. It is worth noting that the electrothermal function of the multifunctional coaxial fiber can promote the rapid desorption of water molecules, thereby improving the efficiency of the swollen fiber to return to its original length. For example, the time taken for the coaxial fiber to desorb water molecules is different under different voltages. At a voltage of 2.5V, the coaxial fiber takes about 590s to completely desorb water molecules, while at a voltage of 10V, the coaxial fiber only takes about 15s to complete the rapid desorption of water molecules.

[0096] Figure 4a The multifunctional coaxial fiber demonstrates its humidity sensing performance. Within a closed environment, as relative humidity increases from 15% to 95%, the fiber's relative resistance changes by approximately 3500%. However, when the relative humidity decreases from 95% to 15%, the relative resistance of the multifunctional coaxial fiber returns to its original state. The fiber's humidity sensing performance is stable, as evidenced by the consistent relative resistance curve over three cycles. Figure 4bThe multifunctional coaxial fiber has a self-sensing property when it stretches in response to humidity changes. The relative resistance of the coaxial fiber changes with the deformation of the fiber. By utilizing this phenomenon, the length change of the fiber can be tracked at all times during the driving process without the need for a distance sensor.

[0097] Example 2

[0098] This embodiment illustrates the preparation and application process of a wound healing dressing, as shown below:

[0099] The multifunctional coaxial composite fibers provided in Example 1 are woven into a wound healing dressing, which can be mixed with other materials to form a complete dressing. However, for ease of demonstration, the wound healing dressings in this embodiment are all arranged longitudinally.

[0100] Along the length direction of the multifunctional coaxial composite fiber, both sides of the wound healing dressing are coated with an adhesive that sticks to the skin, and electrodes are formed at both ends of the multifunctional coaxial composite fiber, and the resistance of the electrodes at both ends can be detected or current can be applied through the electrodes.

[0101] Based on the excellent driving, humidity sensing and electrothermal functions, this multifunctional coaxial fiber shows good application prospects in thermal therapy and wound monitoring / healing. Its applications include Figure 5a shown.

[0102] The humidity sensing function of the multifunctional coaxial fiber can monitor the blood or tissue fluid leakage from the wound. In the application verification of monitoring wound bleeding, the coaxial fiber was placed in a moist environment simulating the wound, and fetal bovine serum was used to simulate the blood leakage from the wound. When fetal bovine serum was dripped onto the multifunctional coaxial fiber, the relative resistance change of the multifunctional coaxial fiber increased instantaneously from the stable state, and then reached the set threshold to activate the alarm, such as Figure 5b Through this process, unexpected bleeding from the wound can be monitored to remind people to seek timely treatment, and most importantly, the following method can be integrated to close the wound through electric current.

[0103] For example, the multifunctional coaxial fiber can quickly absorb fetal bovine serum and then generate a large water-adaptive contraction force as the water molecules are desorbed, making it a potential biomedical material for wound healing. Applying an appropriate voltage can accelerate the desorption of water molecules and provide a suitable temperature to prevent wound infection. Different voltages can precisely control the shrinkage rate of the fiber and achieve precise adjustment for different wounds. In order to verify the properties of coaxial fibers in promoting wound healing, Figure 5c and Figure 5dA biological model was established using agar hydrogel to simulate injured human skin. Coaxial fibers were fixed at both ends of two separate agar gels, separated by a 1mm-wide gap. When a 5V voltage was applied, the coaxial fibers caused the two separated gels to close within 90 seconds, representing a process that promotes wound healing. In practical applications, real-time resistance detection can reflect tissue fluid exudation, automatically energizing the device and physically closing the wound without changing dressings or performing other medical treatments. This offers significant advantages over traditional monitoring and dressing changes or suturing to stop bleeding, both in terms of response speed and reducing secondary damage to the wound.

[0104] Example 3

[0105] This embodiment also illustrates the preparation process of a multifunctional coaxial composite fiber, which is substantially the same as that of Example 1, with the main differences being:

[0106] Sodium alginate was replaced by chitosan, MXene was replaced by graphene, and silver nanowires were replaced by gold nanowires of the same size.

[0107] The multifunctional coaxial composite fiber prepared also has multiple functional integrated effects of humidity sensing, electrothermal drive, moisture adsorption and motion sensing.

[0108] Example 4

[0109] This embodiment also illustrates the preparation process of a multifunctional coaxial composite fiber, which is substantially the same as that of Example 1, with the main differences being:

[0110] Sodium alginate was replaced by cellulose (molecular weight 30,000-80,000), MXene was replaced by carbon nanotubes, and silver nanowires were replaced by copper nanowires of the same size.

[0111] The multifunctional coaxial composite fiber prepared also has multiple functional integrated effects of humidity sensing, electrothermal drive, moisture adsorption and motion sensing.

[0112] Example 5

[0113] This embodiment also illustrates the preparation process of a multifunctional coaxial composite fiber, which is substantially the same as that of Example 1, with the main differences being:

[0114] In the first spinning solution, the mass fraction of gelatin was adjusted to 1.5 wt %, the mass fraction of sodium alginate was adjusted to 3.5 wt %, and the mass fraction of silicon dioxide nanoparticles was adjusted to 0.75 wt %.

[0115] In the second spinning solution, the mass fraction of sodium alginate was adjusted to 0.4 wt %, the mass fraction of MXene was adjusted to 1 wt %, and the mass fraction of silver nanowires was adjusted to 4 wt %.

[0116] The multifunctional coaxial composite fiber prepared also has multiple functional integrated effects of humidity sensing, electrothermal drive, moisture adsorption and motion sensing.

[0117] Example 6

[0118] This embodiment also illustrates the preparation process of a multifunctional coaxial composite fiber, which is substantially the same as that of Example 1, with the main differences being:

[0119] In the first spinning solution, the mass fraction of gelatin was adjusted to 3.5 wt %, the mass fraction of sodium alginate was adjusted to 1.5 wt %, and the mass fraction of silicon dioxide nanoparticles was adjusted to 1.25 wt %.

[0120] In the second spinning solution, the mass fraction of sodium alginate was adjusted to 0.6 wt %, the mass fraction of MXene was adjusted to 3 wt %, and the mass fraction of silver nanowires was adjusted to 6 wt %.

[0121] The multifunctional coaxial composite fiber prepared also has multiple functional integrated effects of humidity sensing, electrothermal drive, moisture adsorption and motion sensing.

[0122] Comparative Example 1

[0123] This comparative example is substantially the same as Example 1, except that:

[0124] Only silver nanowires are added to the second spinning solution without adding MXene, using a single conductive material.

[0125] As a result, the brittleness of the coaxial composite fiber increases, the conductivity decreases, the sensitivity and accuracy of the humidity-responsive resistance change decrease significantly, and the humidity-responsive driving amount also decreases. This makes it impossible to fully achieve the technical effects of sensing tissue fluid exudation, issuing an alarm, and accelerating contraction when used in the preparation of wound dressings.

[0126] Comparative Example 2

[0127] This comparative example is substantially the same as Example 1, except that:

[0128] Only MXene is added without silver nanowires, and a single conductive material is used.

[0129] As a result, the flexibility of the coaxial composite fiber increases, the corresponding fiber humidity response shrinkage force decreases significantly, the electrical conductivity decreases, and the sensitivity and accuracy of humidity response resistance changes decrease. This makes it impossible to fully achieve the technical effects of sensing tissue fluid exudation, issuing an alarm, and accelerating contraction when used in the preparation of wound dressings.

[0130] Comparative Example 3

[0131] This comparative example is substantially the same as Example 1, except that:

[0132] Instead of using a coaxial preparation method, liquid phase spinning is first used to form a fiber core, and then a second spinning solution containing MXene silver nanowires and sodium alginate is coated on the fiber core as a coating slurry, which is then dried to form a sheath layer.

[0133] The sheath formed on the surface by the coating method is not uniform enough, and the bonding between the sheath and the fiber core is also insufficient, which will affect the electrical conductivity of the fiber. In addition, the thickness cannot be precisely controlled, and ultimately the shrinkage performance of the wound healing dressing prepared by it is still poor, and the physical closure of the wound cannot be accelerated. In addition, this method increases the complexity of the preparation process, making it difficult to achieve large-scale batch preparation.

[0134] Based on the above embodiments and comparative examples, it can be clearly seen that the multifunctional coaxial composite fiber provided in the embodiments of the present invention has multifunctional synergistic coaxial composite fibers with electrothermal effect, humidity sensing and self-sensing drive. The integrated preparation method saves costs and can realize batch production.

[0135] Furthermore, the various functions of the coaxial fiber are not independent and superimposed, but rather work in synergy. The electrothermal and drive functions work synergistically, exhibiting water absorption and humidity-size responsiveness. The electrothermal function also assists in the rapid desorption of water molecules, improving the drive response rate. The humidity sensing function and the electrothermal-assisted drive function work synergistically, allowing the coaxial fiber to monitor changes in wound humidity and sense wound exudate, then issue reminders in various ways and quickly adjust the wound's contraction state.

[0136] The multifunctional coaxial composite fiber provided by the embodiment of the present invention has a clear application direction and can be applied in the direction of wound healing and monitoring, and can achieve very excellent wound monitoring and healing promotion effects.

[0137] It should be understood that the above embodiments are merely illustrative of the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent variations or modifications made in accordance with the spirit and substance of the present invention are intended to be encompassed within the scope of protection of the present invention.

Claims

1. A multifunctional coaxial composite fiber, characterized in that: comprising a coaxially arranged fiber core and a sheath; The fiber core comprises a composite of a selected hydrophilic polymer, gelatin, and silica nanoparticles, wherein the selected hydrophilic polymer is selected from any one or a combination of two or more of sodium alginate, chitosan, and cellulose, and the selected hydrophilic polymer and the gelatin molecular chain form a double network structure, and the double network structure locks the silica nanoparticles; The sheath layer includes a composite of a selected hydrophilic polymer, a non-metallic conductive material, and metal nanowires.

2. The multifunctional coaxial composite fiber according to claim 1, characterized in that: The non-metallic conductive material includes any one or a combination of two or more of MXene, graphene, and carbon nanotubes; The metal nanowires include any one of copper nanowires, silver nanowires, and gold nanowires, or a combination of two or more thereof.

3. The multifunctional coaxial composite fiber according to claim 1, characterized in that: The metal nanowire has a length of 6-22 μm and a diameter of 20-120 nm.

4. The multifunctional coaxial composite fiber according to claim 1, characterized in that: The mass ratio of the hydrophilic polymer, gelatin and silica nanoparticles in the fiber core is selected to be 3-7:3-7:0.5-2.5; and / or, the diameter of the fiber core is 100-400 μm; And / or, the thickness of the sheath layer is 10-50 μm.

5. The multifunctional coaxial composite fiber according to claim 1, characterized in that: The multifunctional coaxial composite fiber is capable of absorbing water; At least one physical property of the multifunctional coaxial composite fiber changes with the moisture content of the multifunctional coaxial composite fiber, the physical property comprising one or more of length, diameter, and electrical resistance; The water content of the multifunctional coaxial composite fiber changes after an electric current is passed through the multifunctional coaxial composite fiber, and the electric current is used to cause the multifunctional coaxial composite fiber to generate an electrothermal effect; And, the resistance of the multifunctional coaxial composite fiber changes with either the length or the diameter of the multifunctional coaxial composite fiber.

6. A method for preparing the multifunctional coaxial composite fiber according to any one of claims 1 to 5, characterized in that: include: Providing a first spinning solution and a second spinning solution, wherein the first spinning solution contains a selected hydrophilic polymer, gelatin, and silica nanoparticles, and the second spinning solution contains a selected hydrophilic polymer, a non-metallic conductive material, and metal nanowires; Allowing the first spinning solution to enter a coagulation bath through a first spinning channel and the second spinning solution to enter a coagulation bath through a second spinning channel to obtain a precursor coaxial fiber, wherein the second spinning channel is coaxially arranged around the first spinning channel; The precursor coaxial fiber is dried to obtain a multifunctional coaxial composite fiber.

7. The preparation method according to claim 6, characterized in that Also includes: After drying the precursor coaxial fiber, the dried fiber is brought into contact with the dispersion of the non-metallic conductive material and then dried again to finally obtain the multifunctional coaxial composite fiber; The mass fraction of the non-metallic conductive material in the dispersion is 1-3%.

8. The preparation method according to claim 6, characterized in that The mass fraction of the selected hydrophilic polymer in the first spinning solution is 1.5-3.5%, the mass fraction of gelatin is 1.5-3.5%, and the mass fraction of silica nanoparticles is 0.25-1.25%; And / or, the mass fraction of the selected hydrophilic polymer in the second spinning solution is 0.4-0.6%, the mass fraction of the non-metallic conductive material is 1-3%, and the mass fraction of the metal nanowires is 4-6%.

9. The preparation method according to claim 6, characterized in that The coagulation bath is a calcium chloride solution with a mass fraction of 3-5%.

10. The preparation method according to claim 6, characterized in that The preparation method of the first spinning solution comprises: The gelatin is first dissolved in water at a temperature above 60° C. to obtain a gelatin solution. When the temperature is cooled to 15-35° C., the selected hydrophilic polymer and silica nanoparticles are dissolved in the gelatin solution.

11. The method for using the multifunctional coaxial composite fiber according to any one of claims 1 to 5, characterized in that: include: The moisture content of the multifunctional coaxial composite fiber is adjusted to change at least one physical property of the multifunctional coaxial composite fiber, wherein the physical property includes one or more of length, diameter, and electrical resistance.

12. The method of use according to claim 11, characterized in that: Specifically include: Current is passed into the multifunctional coaxial composite fiber to adjust the water content of the multifunctional coaxial composite fiber through electrothermal effect.

13. Use of the multifunctional coaxial composite fiber according to any one of claims 1 to 5 in the preparation of a medical product, wherein the medical product has at least one of the functions of monitoring wound changes, promoting wound healing, and thermal therapy; The medical product obtains changes in wound exudate by detecting changes in the resistance of the multifunctional coaxial composite fiber; When the medical product detects that the resistance change of the multifunctional coaxial composite fiber exceeds a preset threshold, an electric current is applied to the multifunctional coaxial composite fiber to promote the desorption of the exudate adsorbed by the multifunctional coaxial composite fiber and to cause the multifunctional coaxial composite fiber to shrink; When the multifunctional coaxial composite fiber contracts, the medical product continues to monitor the contraction of the multifunctional coaxial composite fiber by monitoring the change in resistance.

14. A device for wound monitoring and treatment, characterized in that: include: The multifunctional coaxial composite fiber according to any one of claims 1 to 5, which is used to be placed on a wound and has its two ends fixedly connected to the skin on both sides of the wound; a monitoring module, electrically connected to the multifunctional coaxial composite fiber, and at least used to monitor the resistance of the multifunctional coaxial composite fiber; The control module is electrically connected to the monitoring module and is at least used to adjust the current input to the multifunctional coaxial composite fiber according to the monitoring signal output by the monitoring module, thereby adjusting the water content of the multifunctional coaxial composite fiber and further changing at least the length of the multifunctional coaxial composite fiber.

15. The wound monitoring and treatment device according to claim 14, characterized in that It also includes an alarm module, which is connected to the monitoring module and / or the control module and is used to issue an alarm message when the monitoring module detects that the resistance of the multifunctional coaxial composite fiber reaches a set threshold.

Images