Pressure gait sensing sterilization insole and preparation method thereof

Abstract

The invention relates to the technical field of insole preparation, in particular to a pressure gait sensing sterilization insole and a preparation method thereof. The preparation method comprises the following steps: preparing the upper insole layer; preparing a control pad; preparing a lower supporting layer; the upper insole layer, the control pad and the lower supporting layer are sequentially aligned from top to bottom and subjected to hot-pressing attachment, and the pressure gait sensing sterilization insole is obtained; the control pad comprises an ionized water gel pressure sensor. In the application, the upper insole layer, the control pad and the lower supporting layer are prepared step by step and are subjected to hot-pressing compounding, so that modular production of the functional layer is realized, and large-scale mass production is facilitated; meanwhile, an ionized water gel pressure sensor is integrated in the control pad, so that the insole breaks through the traditional single protection function and integrates the dual core functions of pressure gait sensing and sterilization, a complex sensing module does not need to be additionally arranged, the function integration level and wearing convenience are both considered, and the composite requirements of exercise monitoring and foot health care can be met.

Description

Technical Field

[0001] This application relates to the field of insole manufacturing technology, and mainly to a pressure gait sensing sterilized insole and its manufacturing method. Background Technology

[0002] Proper gait is crucial for exercise, as incorrect gait can lead to various degrees of sports injuries over time. Studies show that gait varies among individuals during exercise, with stride width and the force exerted on the forefoot and heel being the primary factors contributing to injuries. Most ordinary insoles on the market only offer basic cushioning and sweat absorption, failing to effectively address foot health issues. Some insoles with massage functions lack scientific and targeted design for their massage protrusions, failing to accurately stimulate foot reflex zones and achieve ideal therapeutic effects. Furthermore, most ordinary shoes on the market do not adequately consider antibacterial functions. Some so-called "antibacterial shoes" often use antibacterial agents added to the upper or insole materials. However, this method has many limitations. Firstly, the effectiveness of antibacterial agents gradually weakens with time and washing, failing to maintain a good antibacterial effect in the long term. Secondly, some antibacterial agents may irritate the skin, posing certain safety risks. Therefore, to meet the growing demand for foot health, it is necessary to provide a therapeutic insole that can sensor and monitor gait to effectively promote foot health.

[0003] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a pressure gait sensing sterilized insole and its preparation method, which aims to solve the problems that existing insoles cannot achieve gait monitoring and that the antibacterial agents used are prone to causing irritation.

[0005] The technical solution of this application is as follows: In a first aspect, this application provides a method for preparing a pressure gait sensing sterilized insole, comprising the following steps: Preparation of the upper insole layer; Preparation of control pads; Prepare the lower support layer; The upper insole layer, the control pad, and the lower support layer are aligned from top to bottom and then heat-pressed together to obtain the pressure gait sensing sterilized insole. The control pad includes an ionized hydrogel pressure sensor.

[0006] Furthermore, the fabrication method of the ion hydrogel pressure sensor includes the following steps: CMC powder, acrylamide, LiCl and MBAA were added sequentially to deionized water and stirred to obtain a basic solution; Modified SP powder was added to the base solution and then ultrasonically dispersed. Add ABS, stir for 1-2 minutes, pour into a mold, and allow to set at room temperature to obtain a gel. Copper wires are fixed at both ends of the gel with aluminum foil as electrodes, and the outer layer is sealed with thick PU tape. The modified SP powder is obtained by modifying SP powder with a silane coupling agent.

[0007] Furthermore, the mass ratio of the CMC powder, the acrylamide, the LiCl, and the MBAA is 10:90-110:85:0.4; The ratio of acrylamide to deionized water is 1:5; The amount of modified SP powder added is 1-3% of the mass of the base solution, and the ultrasonic dispersion power is 100-200W, and the time is 15-30min. The amount of ABS added is 0.5-0.1% of the mass of the base solution, and the time for obtaining gel at room temperature is 2-4 hours.

[0008] Furthermore, the step of preparing the upper insole layer includes: A flexible substrate is selected, and an upwardly protruding arch support is formed by molding, with its position corresponding to the arch area. An ultraviolet lamp assembly is installed in the forefoot and heel areas of a flexible substrate. The ultraviolet lamp assembly includes miniature ultraviolet LEDs, and their positions correspond to the acupoints on the sole of the foot. The micro UV LED has a wavelength of 100-280nm, an operating voltage of 2.5-4.0V, and a light emission angle of 120°.

[0009] Furthermore, the step of preparing the control pad includes: An insulating substrate is selected on which control components, ultraviolet lamp components, Bluetooth components, power supply components and radio electromagnetic positioning elements are mounted. Microcontroller components and signal input interface components are soldered onto the control components. After attaching the trigger plate and the lower trigger plate to the ion hydrogel pressure sensor, the forefoot area and heel area are mounted on the insulating substrate to obtain the pressure testing assembly. The control component, the ultraviolet lamp component, the Bluetooth component, the power supply component, the radio electromagnetic positioning element, and the pressure testing component are connected by wires to form a complete circuit.

[0010] Furthermore, the step of preparing the lower support layer includes: A flexible substrate is selected, and a honeycomb-like structure is formed using a mold. Prepare TiO2 cellulose aerogel and fill it into the cavity of the honeycomb-like structure; The honeycomb-like structure is a hexagonal cavity with a side length of 2-5 mm and a wall thickness of 0.3-0.5 mm.

[0011] Furthermore, the step of preparing TiO2 cellulose aerogel includes: Natural bamboo fiber is dispersed in a solvent and stirred vigorously to obtain a cellulose solution; TiO2 nanoparticles were added to the cellulose solution to obtain a mixed solution, which was then added dropwise to the regeneration solution and solidified. Rinse with deionized water for 12-15 hours, and exchange with ethanol more than 3 times to obtain the precursor; The precursor was freeze-dried at -50~-60℃ for 36-48 hours; The solvent is prepared by mixing sodium hydroxide, urea and water in a mass ratio of 7:12:81. The mass ratio of the natural bamboo fiber to the solvent is 1:45-55, and the temperature of the vigorous stirring is -12℃. The mass ratio of the TiO2 nanoparticles to the natural bamboo fiber is 1-2:20; The regeneration solution is prepared by mixing citric acid and acetic acid in a mass ratio of 1:3-5, and the mass ratio of the cellulose solution to the regeneration solution is 1:5-8.

[0012] Furthermore, the preparation method of the TiO2 nanoparticles includes the following steps: Mix tetrabutyl titanate with anhydrous ethanol and stir at 300-500 r / min for 30-40 min. The reaction is carried out at 110-130℃ for 4-5 hours. Wash three times with ethanol and once with deionized water. After each wash, centrifuge at 3700 rpm for 5 min. Dry at 80-90℃ for 24-30 hours, then calcine at 600-1000℃ for 6-8 hours; The volume ratio of tetrabutyl titanate to anhydrous ethanol is 1:28-30.

[0013] Furthermore, the hot-press bonding is performed by coating a 0.1-0.2 mm thick hot melt adhesive film at a temperature of 80-100℃, a pressure of 0.3-0.5 MPa, and a time of 5-10 min.

[0014] Secondly, this application provides a pressure gait sensing sterilized insole, which is prepared by the method for preparing pressure gait sensing sterilized insoles as described in the first aspect.

[0015] Beneficial effects: In this application, the upper insole layer, control pad, and lower support layer are prepared in steps and then hot-pressed together to achieve modular production of functional layers, which is convenient for mass production. At the same time, the control pad integrates an ion hydrogel pressure sensor, which enables the insole to break through the traditional single protective function and integrate the dual core functions of pressure gait sensing and sterilization. There is no need to add an additional complex sensing module, which takes into account both functional integration and wearing convenience, and meets the combined needs of sports monitoring and foot health care. Detailed Implementation

[0016] This application provides a pressure gait sensing sterilized insole and its preparation method. To make the purpose, technical solution, and effects of this application clearer and more explicit, the following provides a more detailed description. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0017] This application provides a method for preparing a pressure gait sensing sterilized insole, comprising the following steps: S1. Prepare the upper insole layer; S2, Prepare the control pad; S3. Prepare the lower support layer; S4. Align the upper insole layer, control pad and lower support layer from top to bottom, and heat press them together to obtain a pressure gait sensing sterilized insole. The control pad includes an ionized hydrogel pressure sensor.

[0018] In this application, the upper insole layer, control pad, and lower support layer are prepared in steps and then hot-pressed together to achieve modular production of the functional layers, which facilitates large-scale mass production. At the same time, the control pad integrates an ion hydrogel pressure sensor, enabling the insole to break through the traditional single protective function and integrate the dual core functions of pressure gait sensing and sterilization. There is no need to add an additional complex sensing module, which balances functional integration and wearing convenience, and meets the combined needs of sports monitoring and foot health care.

[0019] Further, in step S1, the step of preparing the upper insole layer includes: S11. Select a flexible substrate and mold an upwardly protruding arch support part, the position of which corresponds to the arch area; S12. Install ultraviolet lamp assemblies in the forefoot and heel areas of the flexible substrate. The ultraviolet lamp assemblies include miniature ultraviolet LEDs, and their positions correspond to the acupoints on the soles of the feet.

[0020] Specifically, the flexible substrate can be a polydimethylsiloxane (PDMS) film or a polyurethane (PU) film, among which a porous film can be used.

[0021] In this application, the arch support component can precisely adapt to the physiological curve of the foot arch, providing stable support for the arch and relieving foot fatigue during prolonged walking or exercise. At the same time, it can physically protect the control components below from damage caused by pressure on the sole of the foot. The ultraviolet lamp component is installed at the acupoints on the sole of the foot, which can achieve ultraviolet sterilization while relying on the physical protrusion and photothermal effect of the micro ultraviolet LED to achieve acupoint therapy. Furthermore, the PDMS flexible substrate has good flexibility and biocompatibility, ensuring that the insole is comfortable to wear and has a high degree of fit to the foot, thus improving the user experience.

[0022] Furthermore, in step S12, the wavelength of the miniature ultraviolet LED is 100-280nm, the operating voltage is 2.5-4.0V, and the emission angle is 120°.

[0023] In this application, the 100-280nm deep ultraviolet band can effectively kill bacteria and fungi inside shoes, reducing foot odor and disease risks at the source. At the same time, it can stimulate the photocatalytic sterilization performance of TiO2 in the subsequent functional layer to achieve synergistic antibacterial effect. The appropriate working voltage can be adapted to the power supply component output to reduce energy consumption. The 120° emission angle can expand the ultraviolet light coverage range, eliminate antibacterial dead spots, and ensure the comprehensiveness of sterilization effect.

[0024] Further, in step S2, the step of preparing the control pad includes: S21. Select an insulating substrate and mount the control component, ultraviolet lamp component, Bluetooth component, power supply component and radio electromagnetic positioning element on it. Solder the microcontroller component and signal input interface component on the control component. S22. After attaching the trigger plate and the lower trigger plate to the ion hydrogel pressure sensor, install them on the forefoot area and heel area on the insulating substrate to obtain the pressure test assembly. S23. Connect the control component, ultraviolet lamp component, Bluetooth component, power supply component, radio electromagnetic positioning element and pressure test component through wires to form a complete circuit.

[0025] The insulating flexible substrate can be a porous, breathable polyimide (PI) film. Three ion-hydrogel pressure sensors can be installed in the forefoot area, and two ion-hydrogel pressure sensors can be installed in the heel area.

[0026] In this application, the integrated installation of functional components enables a compact circuit layout that is compatible with the ultra-thin design of the insole; the assembly of the pressure testing component can accurately collect pressure data of the forefoot and heel, and with the help of the wireless electromagnetic positioning element, it can also acquire motion parameters such as gait and stride width; the Bluetooth component supports remote data transmission, making it convenient for users to monitor their exercise status in real time; the complete circuit connection ensures that each functional module responds in concert, enabling precise control of functions such as UV lamp start / stop and pressure sensing, and improving the adjustability of the insole.

[0027] Furthermore, in step S22, the method for preparing the ion hydrogel pressure sensor includes the following steps: S221. Add CMC (sodium carboxymethyl cellulose) powder, acrylamide, LiCl and MBAA (N,N'-methylenebisacrylamide) to deionized water in sequence and stir to obtain a basic solution; S222, After adding modified SP powder to the base solution, disperse it by ultrasonication; S223, add ABS, stir for 1-2 minutes, pour into a mold, and mold at room temperature to obtain a gel; S224. Use aluminum foil to fix copper wires to both ends of the gel as electrodes, and seal the outer layer with thick PU tape.

[0028] In this mixture, MBAA is a crosslinking agent and ABS is an initiator.

[0029] In this application, the gel matrix formed by compounding raw materials such as CMC and acrylamide has good flexibility and tensile properties, which can meet the deformation requirements of repeated pressure on the sole of the foot; the addition of modified SP powder can build a stable conductive network, improve the pressure response sensitivity and stability of the sensor; the design of aluminum foil electrode and PU tape sealing can not only ensure conductivity, but also isolate interference from external factors such as sweat, extend the service life of the sensor, and provide a reliable core component for gait pressure sensing.

[0030] Further, in step S221, the mass ratio of CMC powder, acrylamide, LiCl and MBAA is 10:90-110:85:0.4; the ratio of acrylamide to deionized water is 1:5.

[0031] In this application, by adjusting the proportions of CMC powder, acrylamide, LiCl, MBAA, and deionized water, the viscosity and crosslinking activity of the base solution can be matched to the gel molding requirements. LiCl can enhance ionic conductivity, and MBAA, as a crosslinking agent, can regulate the pore size and mechanical strength of the gel network. The synergistic effect of the proportions of each raw material ensures uniform gel molding and stable conductivity, avoiding sensor malfunction due to imbalance in the ratio.

[0032] Furthermore, in step S223, the amount of ABS added is 0.5-0.1% of the mass of the base solution, and the time to obtain gel at room temperature is 2-4 hours.

[0033] In this application, by adding an appropriate amount of ABS, it is possible to avoid excessive initiator leading to gel embrittlement or insufficient initiator leading to incomplete polymerization; the molding time of 2-4 hours can ensure that the gel network is fully cross-linked, and at the same time, no additional heating equipment is required at room temperature, which simplifies the preparation process, reduces production costs, and the molded gel has good elasticity and conductivity.

[0034] Further, in step S222, the amount of modified SP powder added is 1-3% of the mass of the base solution, the ultrasonic dispersion power is 100-200W, and the time is 15-30min.

[0035] In this application, by controlling the amount of SP powder added, it is possible to construct a continuous conductive path while avoiding excessive powder agglomeration that could affect the gel's flexibility. Ultrasonic treatment ensures that the modified SP powder is uniformly dispersed in the gel matrix, forming a stable conductive network, which improves the sensor's response accuracy and speed to pressure and ensures the accuracy of gait pressure data acquisition.

[0036] Further, the modified SP powder is obtained by modifying SP powder with a silane coupling agent, the steps of which include: SP powder was dispersed in anhydrous ethanol to obtain an SP dispersion. KH570 was dispersed in a 1:9 volume ratio of deionized water to anhydrous ethanol mixture, the pH was adjusted to 4-5 with glacial acetic acid, and the mixture was stirred at room temperature for 30 min to hydrolyze the solution and obtain the modified solution. Add the modification solution to the SP dispersion, stir at 60-70℃ for 4-6 hours, then wash three times with anhydrous ethanol by centrifugation, and then dry in an 80℃ oven for 6 hours to obtain modified SP powder.

[0037] The ratio of SP powder to anhydrous ethanol in the SP dispersion was 1:10 (g / mL); the ratio of KH570 to the deionized water-anhydrous ethanol mixture was 1:25 (g / mL); and the centrifugation washing speed was 3500 rpm, with each washing session lasting 5 min.

[0038] In this application, the hydrolysis products of KH570 can condense with the hydroxyl groups on the surface of SP powder to achieve grafting modification of SP powder, which can improve the hydrophilicity and dispersibility of SP powder, making it tightly bonded to the hydrogel matrix and preventing the conductive network from breaking under pressure. The modification method provided helps to prepare modified SP powder with good conductivity and compatibility, providing core material support for the high performance of ion hydrogel pressure sensors.

[0039] Furthermore, in step S3, the step of preparing the lower support layer includes: S31. Select a flexible substrate and mold a honeycomb structure. S32. Prepare TiO2 cellulose aerogel and fill it into the honeycomb-like cavity; S33. The honeycomb-like structure is a hexagonal cavity with a side length of 2-5mm and a wall thickness of 0.3-0.5mm.

[0040] Specifically, the flexible substrate can be a polydimethylsiloxane (PDMS) film or a polyurethane (PU) film, among which a porous film can be used.

[0041] In this application, the hexagonal cavities with a honeycomb-like structure can achieve excellent cushioning and shock absorption, adapting to the impact of foot pressure during sports activities. At the same time, the hollowed-out gaps can improve breathability and moisture wicking performance. After TiO2 cellulose aerogel is filled into the cavities, it can further enhance breathability and sterilization capabilities. The flexible nature of the PDMS substrate ensures that the flexibility of the lower support layer and the overall insole is matched, taking into account both sports protection and improvement of the foot microenvironment. The 2-5mm cavity side length and 0.3-0.5mm wall thickness of the honeycomb structure can balance structural support and lightness, avoiding the insole being too heavy and affecting the wearing experience.

[0042] Further, in step S32, the step of preparing TiO2 cellulose aerogel includes: S321. Disperse natural bamboo fiber in a solvent and stir vigorously to obtain a cellulose solution; S322. Add TiO2 nanoparticles to a cellulose solution to obtain a mixed solution. Add the mixed solution dropwise to a regeneration solution and solidify. S323, rinse with deionized water for 12-15 hours, and exchange with ethanol more than 3 times to obtain the precursor; S324. Freeze-dry the precursor at -50~-60℃ for 36-48 hours.

[0043] In this application, by introducing TiO2 nanoparticles into the cellulose solution, the porous structure of cellulose aerogel and the photocatalytic performance of TiO2 are combined, which not only retains the air permeability and moisture absorption properties of the aerogel, but also endows it with sterilization function. Multiple rounds of washing and freeze drying can remove residual impurities and completely preserve the porous structure, ensuring the performance stability of the aerogel. After being filled into a honeycomb-like structure, it can form a synergistic antibacterial system with the ultraviolet lamp component, improving the overall sterilization effect of the insole.

[0044] Further, in step S321, the solvent is prepared by mixing sodium hydroxide, urea and water in a mass ratio of 7:12:81.

[0045] In this application, the provided solvent system can efficiently dissolve natural bamboo fiber at low temperatures, breaking the hydrogen bonds between fiber molecules to form a uniform cellulose solution.

[0046] Further, in step S322, the mass ratio of natural bamboo fiber to solvent is 1:45-55, and the temperature for vigorous stirring is -12℃; the mass ratio of TiO2 nanoparticles to natural bamboo fiber is 1-2:20; the regeneration solution is prepared by mixing citric acid and acetic acid in a mass ratio of 1:3-5, and the mass ratio of cellulose solution to regeneration solution is 1:5-8.

[0047] In this application, by controlling the mass ratio of natural bamboo fiber to solvent, it is possible to ensure that the fiber is fully dissolved and the solution concentration is suitable for molding requirements. The stirring temperature of -12℃ can inhibit fiber degradation. By controlling the mass ratio of TiO2 nanoparticles to bamboo fiber, the sterilization performance of the aerogel can be guaranteed without affecting its porous structure. The appropriate proportion of cellulose solution in the regenerated solution can achieve mild curing of cellulose, forming a gel structure with both toughness and strength, which is suitable for the compression and bending scenarios of long-term wear of insoles.

[0048] The preparation method of TiO2 nanoparticles includes the following steps: Mix tetrabutyl titanate with anhydrous ethanol and stir at 300-500 r / min for 30-40 min. The reaction is carried out at 110-130℃ for 4-5 hours. Wash three times with ethanol and once with deionized water. After each wash, centrifuge at 3700 rpm for 5 min. Dry at 80-90℃ for 24-30 hours, then calcine at 600-1000℃ for 6-8 hours; The volume ratio of tetrabutyl titanate to anhydrous ethanol is 1:28-30.

[0049] In this application, by controlling parameters such as the ratio of tetrabutyl titanate to anhydrous ethanol, stirring speed, and reaction temperature, TiO2 nanoparticles with uniform particle size and high crystallinity can be prepared. These nanoparticles exhibit excellent photocatalytic activity and can efficiently respond to ultraviolet light to achieve sterilization. Multiple rounds of washing and centrifugation can remove impurities, and the calcination process can enhance the stability of the crystal structure, providing high-performance antibacterial components for TiO2 cellulose aerogel and ensuring the long-lasting sterilization function of the insole.

[0050] Further, in step S4, hot pressing is performed by coating a 0.1-0.2 mm thick hot melt adhesive film at a temperature of 80-100℃, a pressure of 0.3-0.5 MPa, and a time of 5-10 min.

[0051] In this application, the thickness of the hot melt adhesive film can ensure interlayer adhesion while avoiding excessive film thickness that could affect the flexibility of the insole. By using appropriate hot pressing parameters, the film can be fully melted without damaging the structure and performance of each functional layer, ensuring that the upper insole layer, control pad, and lower support layer are tightly bonded, preventing delamination during use, and improving the overall structural stability and service life of the insole.

[0052] This application also provides a pressure gait sensing sterilized insole, which is prepared by the method described above. The resulting insole integrates multiple functions such as pressure gait monitoring, ultraviolet sterilization, acupoint therapy, and cushioning. The various functional modules work together to achieve accurate monitoring of gait, assist in posture correction and fall risk assessment, and effectively improve the in-shoe microenvironment and prevent foot diseases. Furthermore, the insole is made of flexible materials, making it comfortable to wear and compatible with various shoe types, thus possessing wide applicability and practical value.

[0053] The following specific examples provide further details.

[0054] Example 1 The preparation method of the pressure gait sensing sterilized insole in Example 1 includes the following steps: (1) Preparation of the upper insole layer.

[0055] (11) Select a 1 mm thick polydimethylsiloxane (PDMS) film as a flexible substrate, and form an upwardly protruding arch support part with a height of 0.8 cm in the arch area using a mold; (12) Install ultraviolet lamp components in the forefoot and heel areas. The parameters of the miniature ultraviolet LEDs in the components are wavelength 200nm, working voltage 3.2V, and light emission angle 120°. The LEDs are distributed according to the acupoints such as Yongquan and Taichong on the sole of the foot.

[0056] (2) Preparation of control pad.

[0057] (21) Select a porous polyimide insulating substrate, and install a control component, an ultraviolet lamp component, a Bluetooth component (HC-08 model), a 3.7V 100mAh lithium battery power component and a radio electromagnetic positioning element on the substrate. Solder a microcontroller component (AT89C51) and a signal input interface component on the control component. (22) Fabrication of an ion-hydrogel pressure sensor: (220) Preparation of modified SP powder: 10g of SP powder was dispersed in 100mL of anhydrous ethanol at a ratio of 1g:10mL to obtain SP dispersion; 2g of KH570 was dispersed in 50mL of a 1:9 mixture of deionized water and anhydrous ethanol at a ratio of 1g:25mL, the pH was adjusted to 4.5 with glacial acetic acid, and the mixture was stirred at room temperature for 30min to obtain modified solution; the modified solution was poured into the SP dispersion, stirred at 65℃ for 5h, centrifuged and washed 3 times (5min each time) at 3500rpm, and dried in an oven at 80℃ for 6h to obtain modified SP powder; (221) Weigh 0.1g CMC powder, 1g acrylamide, 0.85g LiCl and 0.004g MBAA in a mass ratio of 10:100:85:0.4, add 5mL of deionized water (acrylamide to deionized water ratio 1:5), and stir to obtain the basic solution; (222) Add 0.02g of modified SP powder at 2% of the mass of the base solution and disperse at 150W ultrasonic power for 20min; (223) Add 0.008g ABS at 0.8% of the base solution mass, stir for 1.5min, pour into a 2cm×2cm×0.4cm mold, let stand at room temperature for 3h to form a gel; ④ S224: Fix copper wires to both ends of the gel with aluminum foil as electrodes, and seal the outer layer with thick PU tape; then assemble upper and lower trigger plates on the sensor, install 3 sensors in the forefoot area and 2 sensors in the heel area to form a pressure test assembly; (23) Connect the components with tin-plated copper wire with a diameter of 0.15mm to form a complete circuit.

[0058] (3) Prepare the lower support layer.

[0059] (30) Pre-preparation of TiO2 nanoparticles: 1 mL of tetrabutyl titanate and 29 mL of anhydrous ethanol were mixed at a volume ratio of 1:29 and stirred at 400 r / min for 35 min; kept at 120℃ for 4.5 h; washed with ethanol 3 times and deionized water once (centrifuged at 3700 rpm for 5 min each time); dried at 85℃ for 27 h and calcined at 800℃ for 7 h to obtain TiO2 nanoparticles.

[0060] (31) Select a 1mm thick PDMS film and form a hexagonal honeycomb structure (cavity side length 3mm, wall thickness 0.4mm) using a mold. (32) Preparation of TiO2 cellulose aerogel: (321) Prepare a NaOH-urea-water solvent in a mass ratio of 7:12:81 and cool it to -12℃; disperse 2g of natural bamboo fiber in 100g of solvent in a mass ratio of 1:50 and stir vigorously at -12℃ for 30min to obtain a cellulose solution; (322) Add 0.15g of TiO2 nanoparticles to cellulose solution at a mass ratio of 1.5:20 and stir to obtain a mixture; prepare a citric acid-acetic acid regeneration solution at a mass ratio of 1:4, and add the mixture dropwise to the regeneration solution at a mass ratio of 1:6, and cure at room temperature for 10min; (323) Rinse with deionized water for 13 hours, and exchange with ethanol 4 times to obtain the precursor; (324) -55℃ freeze-drying for 42h yields TiO2 cellulose aerogel, which is then used to fill honeycomb-like cavities; (4) Hot pressing composite.

[0061] A 0.15mm thick EVA hot melt adhesive film was coated between the upper insole layer and the control pad, and between the control pad and the lower support layer. The film was then hot-pressed at 85℃ and 0.4MPa pressure for 8 minutes and cut into 30cm×10cm sizes to obtain a pressure gait sensing sterilized insole.

[0062] Example 2 The preparation method of the pressure gait sensing sterilized insole in Example 2 is basically the same as that in Example 1, except that the mass ratio of CMC powder, acrylamide, LiCl and MBAA in Example 2 is changed to 10:90:85:0.4, the amount of ABS added is 0.5% of the mass of the base solution, and the room temperature molding time is extended to 4 hours; the TiO2 cellulose aerogel has a mass ratio of natural bamboo fiber to solvent of 1:45, a mass ratio of TiO2 nanoparticles to bamboo fiber of 1:20, and a mass ratio of citric acid to acetic acid in the regenerated solution of 1:3.

[0063] Example 3 The preparation method of the pressure gait sensing sterilized insole in Example 3 is basically the same as that in Example 1, except that the flexible substrate of the upper insole layer and the lower support layer in Example 3 is replaced with a 1.2mm thick polyurethane film; the amount of modified SP powder added is 3% of the mass of the base solution, the ultrasonic power is 200W, and the time is 30min; the honeycomb structure is 5mm in side length and 0.5mm in wall thickness; the hot-pressing composite is 0.2mm thick hot melt adhesive film, the hot-pressing temperature is 100℃, the pressure is 0.5MPa, and the time is 5min.

[0064] Comparative Example 1 Comparative Example 1 The preparation method of the insole of Comparative Example 1 is basically the same as that of Example 1. The only difference is that Comparative Example 1 does not modify the SP powder, but directly adds the SP powder to the base solution to prepare the ion hydrogel sensor. The remaining steps and parameters are the same as those of Example 1.

[0065] Comparative Example 2 The preparation method of the insole in Comparative Example 2 is basically the same as that in Example 1. The only difference is that Comparative Example 2 only forms a honeycomb-like structure, without preparing and filling TiO2 cellulose aerogel, and directly uses the hollow honeycomb-like structure as the lower support layer. The remaining steps and parameters are the same as those in Example 1.

[0066] The insoles prepared in Examples 1-3 and Comparative Examples 1-2 were subjected to performance tests, and the test items are as follows: (I) Pressure sensing sensitivity: A universal testing machine was used to apply a step pressure of 0-150 kPa to the sensor, and the sensor resistance response time and pressure measurement error were recorded.

[0067] (II) Antibacterial and sterilization properties: Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922), common pathogens of the soles of the feet, were selected, and the inoculation concentration was 1×10⁻⁶. 6 The bacterial suspension of CFU / mL was cultured with the forefoot area samples (2cm×2cm) of the insoles of Examples 1-3 and Comparative Examples 1-2 at 37℃ for 24h with shaking. The micro UV LED was turned on (working for 1h), and the antibacterial rate was calculated by plate counting method. At the same time, the samples were washed with water 5 times to test the antibacterial rate after washing.

[0068] (III) Structural durability: Refer to GB / T 3903.1-2008 to conduct 10,000 cycles of bending test (bending angle ±30°), frequency 30 times / min, 10,000 cycles. After the test, check the circuit continuity (resistance change rate ≤10% is qualified) and the integrity of aerogel.

[0069] (IV) Breathability: The breathability of different areas of the insole (forefoot, arch, and heel) was tested using a fabric breathability meter under a pressure of 100Pa, and the average value was taken.

[0070] The performance test data of Examples 1-3 and Comparative Examples 1-2 are shown in Table 1: Table 1 Comparative performance test data revealed that Examples 1-3, employing modified SP powder to construct a stable conductive network, exhibited fast sensing response and low error. The TiO2 cellulose aerogel and UV LED synergistically provided antibacterial protection, maintaining a high antibacterial rate even after washing. The functional layers were tightly bonded, resulting in stable circuitry and aerogel with good permeability. In Comparative Example 1, the unmodified SP powder easily agglomerated, leading to unstable conductive pathways, a significant decrease in sensitivity, and sensor failure during bending cycles, impacting sensing performance. Comparative Example 2, lacking TiO2 cellulose aerogel and relying solely on UV LED sterilization, showed poor antibacterial effect of the support layer, with a significant decrease in antibacterial effect after washing. Furthermore, the hollow structure was prone to collapse under pressure, significantly reducing permeability.

[0071] The pressure gait sensing sterilized insole prepared by the method provided in this application can monitor foot pressure and gait while ensuring antibacterial effect, making it easy to integrate other physiotherapy functions and ensuring the user experience of the insole.

[0072] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of this application.

Claims

1. A method for preparing a pressure gait sensing sterilized insole, characterized in that, Includes the following steps: Preparation of the upper insole layer; Preparation of control pads; Prepare the lower support layer; The upper insole layer, the control pad, and the lower support layer are aligned from top to bottom and then heat-pressed together to obtain the pressure gait sensing sterilized insole. The control pad includes an ionized hydrogel pressure sensor.

2. The method for preparing the pressure gait sensing sterilized insole according to claim 1, characterized in that, The fabrication method of the ion hydrogel pressure sensor includes the following steps: CMC powder, acrylamide, LiCl and MBAA were added sequentially to deionized water and stirred to obtain a basic solution; Modified SP powder was added to the base solution and then ultrasonically dispersed. Add ABS, stir for 1-2 minutes, pour into a mold, and allow to set at room temperature to obtain a gel. Copper wires are fixed at both ends of the gel with aluminum foil as electrodes, and the outer layer is sealed with thick PU tape. The modified SP powder is obtained by modifying SP powder with a silane coupling agent.

3. The method for preparing the pressure gait sensing sterilized insole according to claim 2, characterized in that, The mass ratio of the CMC powder, the acrylamide, the LiCl, and the MBAA is 10:90-110:85:0.

4. The ratio of acrylamide to deionized water is 1:5; The amount of modified SP powder added is 1-3% of the mass of the base solution, and the ultrasonic dispersion power is 100-200W, and the time is 15-30min. The amount of ABS added is 0.5-0.1% of the mass of the base solution, and the time for obtaining gel at room temperature is 2-4 hours.

4. The method for preparing pressure gait sensing sterilized insoles according to claim 2, characterized in that, The steps for preparing the upper insole layer include: A flexible substrate is selected, and an upwardly protruding arch support is formed by molding, with its position corresponding to the arch area. An ultraviolet lamp assembly is installed in the forefoot and heel areas of a flexible substrate. The ultraviolet lamp assembly includes miniature ultraviolet LEDs, and their positions correspond to the acupoints on the sole of the foot. The micro UV LED has a wavelength of 100-280nm, an operating voltage of 2.5-4.0V, and a light emission angle of 120°.

5. The method for preparing the pressure gait sensing sterilized insole according to claim 4, characterized in that, The steps for preparing the control pad include: An insulating substrate is selected on which control components, ultraviolet lamp components, Bluetooth components, power supply components and radio electromagnetic positioning elements are mounted. Microcontroller components and signal input interface components are soldered onto the control components. After attaching the trigger plate and the lower trigger plate to the ion hydrogel pressure sensor, the forefoot area and heel area are mounted on the insulating substrate to obtain the pressure testing assembly. The control component, the ultraviolet lamp component, the Bluetooth component, the power supply component, the radio electromagnetic positioning element, and the pressure testing component are connected by wires to form a complete circuit.

6. The method for preparing the pressure gait sensing sterilized insole according to claim 1, characterized in that, The steps for preparing the lower support layer include: A flexible substrate is selected, and a honeycomb-like structure is formed using a mold. Prepare TiO2 cellulose aerogel and fill it into the cavity of the honeycomb-like structure; The honeycomb-like structure is a hexagonal cavity with a side length of 2-5 mm and a wall thickness of 0.3-0.5 mm.

7. The method for preparing the pressure gait sensing sterilized insole according to claim 6, characterized in that, The steps for preparing TiO2 cellulose aerogel include: Natural bamboo fiber is dispersed in a solvent and stirred vigorously to obtain a cellulose solution; TiO2 nanoparticles were added to the cellulose solution to obtain a mixed solution, which was then added dropwise to the regeneration solution and solidified. Rinse with deionized water for 12-15 hours, and exchange with ethanol more than 3 times to obtain the precursor; The precursor was freeze-dried at -50~-60℃ for 36-48 hours; The solvent is prepared by mixing sodium hydroxide, urea and water in a mass ratio of 7:12:

81. The mass ratio of the natural bamboo fiber to the solvent is 1:45-55, and the temperature of the vigorous stirring is -12℃. The mass ratio of the TiO2 nanoparticles to the natural bamboo fiber is 1-2:20; The regeneration solution is prepared by mixing citric acid and acetic acid in a mass ratio of 1:3-5, and the mass ratio of the cellulose solution to the regeneration solution is 1:5-8.

8. The method for preparing the pressure gait sensing sterilized insole according to claim 7, characterized in that, The preparation method of the TiO2 nanoparticles includes the following steps: Mix tetrabutyl titanate with anhydrous ethanol and stir at 300-500 r / min for 30-40 min. The reaction is carried out at 110-130℃ for 4-5 hours. Wash three times with ethanol and once with deionized water. After each wash, centrifuge at 3700 rpm for 5 min. Dry at 80-90℃ for 24-30 hours, then calcine at 600-1000℃ for 6-8 hours; The volume ratio of tetrabutyl titanate to anhydrous ethanol is 1:28-30.

9. The method for preparing the pressure gait sensing sterilized insole according to claim 1, characterized in that, The hot-press bonding is performed by coating a 0.1-0.2mm thick hot melt adhesive film at a temperature of 80-100℃, a pressure of 0.3-0.5MPa, and a time of 5-10min.

10. A pressure gait sensing sterilization insole, characterized in that, It is prepared by the method for preparing pressure gait sensing sterilized insoles as described in any one of claims 1-9.

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