An ionic sensing slurry and a preparation method thereof, a textile ionic sensor and a preparation method and application thereof

Abstract

The application provides an ion sensing slurry and a preparation method thereof, a textile ion sensor and a preparation method and application thereof, and relates to the technical field of sensors.The ion sensing slurry provided by the application comprises graphene, water-based polyurethane and silk fibroin; the mass of the silk fibroin is 5-25% of the total mass of the graphene and the water-based polyurethane; and the mass of the graphene is 5-15% of the total mass of the graphene and the water-based polyurethane.The ion sensing slurry provided by the application has the function of ion sensing, is printed onto the surface of a fabric, and the obtained textile ion sensor can effectively detect urine protein in urine, realizes the monitoring of human life and health, and has good mechanical strength and bending resistance.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and in particular to an ion-sensing slurry and its preparation method, a textile ion sensor and its preparation method and application. Background Technology

[0002] Wearable sensing textile technology has become a research hotspot in fields such as biomedicine, health monitoring, military, and aerospace. Emerging sensing materials can be categorized into strain sensors, pressure sensors, and ion sensors, depending on the type of stimuli from the environment and objects. With the rapid development of technology, textiles with sensing functions are finding increasingly wider applications in health monitoring.

[0003] To date, humidity-sensing fabrics, temperature-sensing fabrics, intelligent electrocardiogram (ECG) detection fabrics, electromyography (EMG) measurement fabrics, and electroencephalogram (EEG) measurement fabrics have been applied in the market. In the near future, intelligent textiles will become the mainstream of the global textile market, and with the improvement of people's living standards and the growth in demand for intelligent textiles, its development prospects will be very broad.

[0004] Due to the many excellent properties of graphene, in recent years, an increasing number of studies have focused on developing graphene-based textile products. This trend is expected to continue in the coming years. For example, Imperial College London designed and fabricated a highly sensitive and stretchable graphene-based TPU / knitted textile strain sensor. When integrated into various wearable devices, this composite sensor can accurately detect various human movements and subtle physiological signals, showing great potential in wearable monitoring devices.

[0005] As we all know, urine is a liquid excretion produced by humans and vertebrates through the urinary system and urinary tract to meet metabolic needs. Urine tests can reveal many diseases. Therefore, the design and development of wearable, close-fitting fabric sensors to accurately monitor urine in different bodily states is of great significance to human life and health, and will further promote the development of disease prevention materials. Summary of the Invention

[0006] The purpose of this invention is to provide an ion-sensing slurry and its preparation method, a textile ion sensor and its preparation method and application. The textile ion sensor provided by this invention can effectively detect urinary protein in urine, thereby enabling the monitoring of human life and health.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0008] The present invention provides an ion sensing slurry comprising graphene, aqueous polyurethane, and silk fibroin; wherein the mass of the silk fibroin is 5-25% of the total mass of graphene and aqueous polyurethane; and the mass of the graphene is 5-15% of the total mass of graphene and aqueous polyurethane.

[0009] Preferably, the mass of the graphene is 12.5 to 15% of the total mass of the graphene and the waterborne polyurethane.

[0010] Preferably, the mass of the silk fibroin is 25% of the total mass of graphene and waterborne polyurethane.

[0011] The present invention provides a method for preparing the ion sensing slurry described above, comprising the following steps: dissolving graphene powder in aqueous polyurethane, mixing the resulting solution with silk fibroin to obtain the ion sensing slurry.

[0012] Preferably, the dissolution and mixing are carried out under stirring conditions.

[0013] The present invention provides a textile ion sensor, comprising a fabric and an ion sensing layer located on the surface of the fabric; the ion sensing layer is formed from the ion sensing slurry described in the above-described scheme or the ion sensing slurry prepared by the preparation method described in the above-described scheme.

[0014] The present invention provides a method for preparing the textile ion sensor described above, comprising the following steps: printing ion sensing paste onto the surface of a fabric, drying it, and obtaining the textile ion sensor.

[0015] Preferably, the printing includes screen printing.

[0016] Preferably, the drying temperature is 60–100°C.

[0017] This invention provides the application of the textile ion sensor described in the above-described scheme or the textile ion sensor prepared by the above-described method in monitoring urine for non-disease diagnosis and treatment purposes.

[0018] This invention provides an ion-sensing paste comprising graphene, aqueous polyurethane, and silk fibroin; the mass of the silk fibroin is 5-25% of the total mass of graphene and aqueous polyurethane; the mass of the graphene is 5-15% of the total mass of graphene and aqueous polyurethane. This invention utilizes the principle that silk fibroin reacts with urinary proteins in urine, and achieves ion sensing functionality by measuring conductivity. By using graphene as a conductive filler and aqueous polyurethane solution as a binder, and controlling the content of the three components within appropriate ranges, the resulting ion-sensing paste possesses excellent printing and sensing properties.

[0019] The results of the embodiments show that the ion sensing paste provided by the present invention has the function of ion sensing. When printed onto the surface of a fabric, the resulting textile ion sensor can monitor urinary protein in urine and has good mechanical strength and bending resistance. Attached Figure Description

[0020] Figure 1 This is a diagram illustrating the screen printing process.

[0021] Figure 2 This is a graph showing the measurement parameters for resistance testing.

[0022] Figure 3 This is a connection diagram for resistance testing instruments;

[0023] Figure 4 This is a picture of the actual protein in urine.

[0024] Figure 5 Resistance values ​​of textile ion sensors with different silk fibroin contents of 15% graphene;

[0025] Figure 6 Resistance values ​​of textile ion sensors with different silk fibroin contents and 12.5% ​​graphene content;

[0026] Figure 7 Resistance values ​​of textile ion sensors with different silk fibroin contents of 10% graphene;

[0027] Figure 8 Resistance values ​​of textile ion sensors with different silk fibroin contents and 7.5% graphene content;

[0028] Figure 9 Resistance values ​​of textile ion sensors with different silk fibroin contents and 5% graphene content;

[0029] Figure 10 Viscosities of ion-sensing slurries with different graphene contents;

[0030] Figure 11 A photograph of a textile ion sensor with different silk fibroin contents and 15% graphene content.

[0031] Figure 12 Images of textile ion sensors with different silk fibroin contents and 12.5% ​​graphene content;

[0032] Figure 13 Images of textile ion sensors with different silk fibroin contents and 10% graphene content;

[0033] Figure 14 Images of textile ion sensors with different silk fibroin contents and 7.5% graphene content;

[0034] Figure 15Images of textile ion sensors with different silk fibroin contents and 5% graphene content;

[0035] Figure 16 SEM images of textile ion sensors with different graphene contents;

[0036] Figure 17 The graph shows the resistance change of a textile ion sensor after different number of washes.

[0037] Figure 18 The graph shows the resistance change of the textile ion sensor under a 45° bend.

[0038] Figure 19 The graph shows the resistance change of the textile ion sensor under a 90° bend.

[0039] Figure 20 The graph shows the resistance change of the textile ion sensor under a 135° bend.

[0040] Figure 21 The graph shows the resistance change of the textile ion sensor when bent at 180°. Detailed Implementation

[0041] The present invention provides an ion sensing slurry comprising graphene, aqueous polyurethane, and silk fibroin; wherein the mass of the silk fibroin is 5-25% of the total mass of graphene and aqueous polyurethane; and the mass of the graphene is 5-15% of the total mass of graphene and aqueous polyurethane.

[0042] In this invention, the mass of the graphene is preferably 12.5-15% of the total mass of graphene and waterborne polyurethane, more preferably 12.5%; the mass of the silk fibroin is preferably 25% of the total mass of graphene and waterborne polyurethane.

[0043] This invention utilizes the principle that silk fibroin responds to urinary proteins, and achieves ion sensing by measuring conductivity. By combining graphene as a conductive filler and aqueous polyurethane solution as a binder, and controlling the content of the three components within a suitable range, the resulting ion sensing paste has excellent printing and sensing performance.

[0044] The present invention provides a method for preparing the ion sensing slurry described above, comprising the following steps: dissolving graphene powder in aqueous polyurethane, mixing the resulting solution with silk fibroin to obtain the ion sensing slurry.

[0045] Unless otherwise specified, all raw materials used in this invention are commercially available products well known in the art.

[0046] This invention dissolves graphene powder in aqueous polyurethane to obtain a solution.

[0047] This invention does not have special requirements for the graphene powder used; any graphene powder well-known in the art can be used. In this invention, the dissolution is preferably carried out under stirring conditions, and the stirring speed is preferably 300–600 r / min. This invention does not have special requirements for the stirring time; stirring until the graphene powder is completely dissolved is sufficient.

[0048] After obtaining the solution, the present invention mixes the solution with silk fibroin to obtain the ion sensing slurry.

[0049] In this invention, the mixing is preferably carried out under stirring conditions. The invention does not have special requirements for the stirring conditions; stirring until the mixture is homogeneous is sufficient. In an embodiment of this invention, the stirring rate is 400 r / min, and the stirring time is 2 min. Silk fibroin has a "multi-block" molecular chain. During the mixing process, silk fibroin causes graphene to spontaneously aggregate or assemble in the aqueous polyurethane, thereby affecting the performance of the ion-sensing slurry.

[0050] The present invention provides a textile ion sensor, comprising a fabric and an ion sensing layer located on the surface of the fabric; the ion sensing layer is formed from the ion sensing slurry described in the above-described scheme or the ion sensing slurry prepared by the preparation method described in the above-described scheme.

[0051] This invention does not impose any special requirements on the fabric used; any fabric well-known in the art can be used, and those skilled in the art can choose according to actual needs. In the embodiments of this invention, the fabric is a commercially available membrane polyester fabric. This invention does not impose any special limitations on the thickness of the ion sensing layer; those skilled in the art can adjust it according to actual needs.

[0052] The present invention provides a method for preparing the textile ion sensor described above, comprising the following steps: printing ion sensing paste onto the surface of a fabric, drying it, and obtaining the textile ion sensor.

[0053] In this invention, the printing preferably includes screen printing; the present invention does not have special requirements for the screen printing process, and a screen printing process well known in the art can be used. In an embodiment of the present invention, the screen printing uses a screen mesh of 150 mesh.

[0054] In this invention, the drying temperature is preferably 60-100°C, more preferably 80°C, and the drying time is preferably 15 minutes.

[0055] The ion sensing paste provided by this invention has a suitable viscosity, is suitable for printing, and has good permeability. When printed onto the surface of a fabric, the resulting textile ion sensor has good sensing performance.

[0056] This invention provides the application of the textile ion sensor described in the above-described scheme or the textile ion sensor prepared by the above-described method in monitoring urine for non-disease diagnosis and treatment purposes.

[0057] The following detailed description, in conjunction with embodiments, illustrates the ion-sensing slurry and its preparation method, the textile ion sensor and its preparation method, and their applications provided by the present invention. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0058] The aqueous polyurethane used in the following examples was purchased from Hefei Tairek New Material Technology Co., Ltd., product model 601A-K.

[0059] Examples 1-25

[0060] (1) Weigh graphene and aqueous polyurethane solution using an electronic balance to prepare five groups of 150g slurries. The graphene content of groups 1 to 5 is 5%, 7.5%, 10%, 12.5%, and 15%, respectively.

[0061] (2) Weigh out the graphene and water-based polyurethane, mix them, and then put them into a mixer. Set the mixing time to 5 min, the speed of groups 1 and 2 to 300 r / min, and the speed of groups 3 to 5 to 600 r / min, so that the graphene is completely dissolved in the water-based polyurethane solution.

[0062] (3) Divide the solution into five equal parts, each weighing 30g, and label them as 1a, 1b, 1c, 1d, and 1e.

[0063] (4) Add 7.5g, 6g, 4.5g, 3g and 1.5g of silk fibroin to the five groups of solutions obtained in step (3), put them into a mixer, set the speed to 400r / min, and stir for 2min to obtain the ion sensing slurry of Examples 1 to 5.

[0064] (5) Perform steps (3) and (4) on groups 2 to 5 to obtain the ion sensing slurry of Examples 6 to 25.

[0065] In Examples 1-25, the percentages of graphene and silk fibroin in the total mass of graphene and waterborne polyurethane are shown in Table 1.

[0066] Table 1 Specific material usage in Examples 1-25

[0067]

[0068] Application Examples 1-25

[0069] Cut 2cm x 2cm pieces of coated polyester fabric and lay them flat under a 150-mesh screen frame. Pour the graphene paste prepared in Examples 1-25 above onto the edge of the screen frame. The starting position is the position where the squeegee begins its forward printing stroke on the screen, and the ending position is the squeegee retraction position. During screen printing, do not push the paste at the retraction position back to the starting position; instead, allow the squeegee to pick up the paste at the retraction position. Then, remove the squeegee with the paste from the screen and return it to the starting position. The squeegee carries the picked-up paste back to the starting position on the screen, and uses the carried-back paste to print on the screen. Repeat this process 3-5 times. Then, place the printed fabric in an 80℃ oven to dry for 15 minutes to obtain a textile ion sensor. See [link to printing operation details] for further instructions. Figure 1 .

[0070] Performance testing:

[0071] (1) Sensing performance

[0072] The resistance of the textile ion sensor corresponding to cases 1-25 is tested using a digital bridge, and the steps are as follows:

[0073] (1) Cut 25 sets of textile ion sensors with different concentrations into four pieces of 2*6cm each;

[0074] (2) Connect the digital bridge instrument to the power supply, turn on the switch, and preheat for 15 minutes;

[0075] (3) Set measurement parameters as follows Figure 2 ;

[0076] (4) Connect the test sample to the instrument, such as Figure 3 ;

[0077] (5) Evenly add five drops of urine protein solution to the middle of three test samples in each group to simulate human urine. The urine protein solution is a standard synthetic test solution purchased from Dongguan Chuangwei Testing Instruments Co., Ltd. on Taobao. The urine protein solutions are acidic (pH 4.6), neutral (pH 6.5), and alkaline (pH 8.5). Do not add urine protein solution to the remaining sample. Figure 4 As shown;

[0078] (6) Click the start button on the computer to perform a resistance test;

[0079] (7) Repeat the above operation with different samples.

[0080] The data obtained in the experiment are summarized as follows:

[0081] (1) Resistance values ​​of textile ion sensors with different silk fibroin contents of 15% graphene (Examples 21-25), such as Figure 5 As shown, the specific data is shown in Table 2.

[0082] Table 2. Resistance values ​​(unit: Ω) of ion sensors for textile printing in Examples 21-25.

[0083]

[0084]

[0085] (2) Resistance values ​​of textile ion sensors with different fibroin contents of 12.5% ​​graphene (Examples 16-20), such as... Figure 6 As shown, the corresponding specific data is shown in Table 3.

[0086] Table 3. Resistance values ​​(unit: Ω) of ion sensors for textile printing in Examples 16-20.

[0087] Silk fibroin content No urine added acidic neutral alkaline 5％ 12534.7 9570.82 12087.5 8238.2 10％ 10799.09 10382.12 10148.2 7725.14 15％ 7810.31 6002.4 6973.72 5927.9 20％ 6628.2 5925.97 5984.65 5229.11 25％ 4588.64 2856.79 2602.14 2311.05

[0088] (3) Resistance values ​​of textile ion sensors with different fibrous protein contents of 10% graphene (Examples 11-15), such as Figure 7 As shown, the corresponding specific data is shown in Table 4.

[0089] Table 4. Resistance values ​​(unit: Ω) of ion sensors for textile printing in Examples 11-15.

[0090] Silk fibroin content No urine added acidic neutral alkaline 5％ 13998.33 13509.72 13508.93 11890.15 10％ 13015.85 12793.22 12759.26 12496.3 15％ 12671.84 12419.56 12430.36 12214.22 20％ 11295.94 10772.04 11064.93 10378.06 25％ 10440.79 10273.35 10219.44 9722.01

[0091] (4) Resistance values ​​of textile ion sensors with different fibroin contents of 7.5% graphene (Examples 6-10), such as... Figure 8 As shown, the corresponding specific data is shown in Table 5.

[0092] Table 5 shows the resistance values ​​(unit: Ω) of the ion sensors for textile printing in Examples 6-10.

[0093]

[0094]

[0095] (5) Resistance values ​​of textile ion sensors with different fibroin contents of 5% graphene (Examples 1-5), such as Figure 9 As shown, the corresponding specific data is shown in Table 6.

[0096] Table 6. Resistance values ​​(unit: Ω) of ion sensors for textile printing in Examples 6-10.

[0097] Silk fibroin content No urine added acidic neutral alkaline 5％ 14200.35 12921.16 13821.2 12863.55 10％ 13553.45 13189.13 13229.48 12892.15 15％ 12982.36 12589.27 12693.64 12339.29 20％ 11937.2 11682.25 11871.25 10238.33 25％ 11392.24 10998.5 11028.32 10027.3

[0098] The horizontal analysis of the above charts shows that in graphene solutions of the same concentration, the resistance of the textile ion sensor decreases with increasing silk fibroin content; when the silk fibroin content is the same, the resistance also decreases with increasing graphene content. This may be because as the graphene content increases, the contact between graphene particles becomes tighter, forming a three-dimensional network that runs through the entire structure. Furthermore, the large number of graphene particles in contact with each other creates excellent conductors, increasing the space for free electron movement and thus reducing the resistance.

[0099] The longitudinal analysis of the above charts shows that: overall, adding urinary protein solution reduces the resistance of the textile ion sensor. Among acidic, neutral, and alkaline urinary protein solutions, the slope of the curve changes most significantly with the addition of alkaline urinary protein solution, resulting in the most pronounced change in resistance. This indicates that alkaline urinary protein solution has the best ion sensing effect for this sizing material. Comparing acidic and neutral urinary protein solutions, the structural changes with acidic urinary protein solution are more pronounced than those with neutral urinary protein solution. Therefore, the sensing performance ranking of the three different types of urinary protein solutions is: alkaline urinary protein solution > acidic urinary protein solution > neutral urinary protein solution.

[0100] By calculating the change in resistance in an alkaline urinary protein solution and comparing the data, it was found that the textile ion sensor exhibited the greatest resistance change when the graphene content was 12.5% ​​and the silk fibroin content was 25%. This means that the ion sensing slurry containing 12.5% ​​graphene and 5% silk fibroin provided the best ion sensing effect. At this concentration, both the silk fibroin and graphene contents were relatively high. In the conductive graphene slurry, the responsiveness between silk fibroin and urinary protein was most pronounced, resulting in the most significant resistance change in the textile ion sensor at this concentration.

[0101] (2) Viscosity test

[0102] This experiment uses an NDJ-1 rotary viscometer. Two consecutive measurements are taken, and the difference between each measurement and the average value must not exceed ±3% of the average value. Otherwise, a third measurement is performed.

[0103] Ion sensing pastes require a certain viscosity (within a specific viscosity range) for application. Furthermore, the viscosity of the paste is related to its penetration into the fabric. If the viscosity is too high, it will not flow; a suitable viscosity results in good flowability and penetration, leading to more uniform and smooth printing on the fabric surface, resulting in better and more stable conductivity and sensing performance. If the paste viscosity is too low, it tends to flow to the sides of the printing screen, causing uneven printing return, poor conductivity of the fabric, and wasted paste.

[0104] This experiment tested the viscosity of slurries (Examples 5, 10, 15, 20, and 25) with a silk fibroin content of 25% and graphene contents of 5%, 7.5%, 10%, 12.5%, and 15%, respectively. The results are as follows: Figure 10 As shown, Figure 10 The specific results are shown in Table 7.

[0105] Table 7 Viscosity test results

[0106] Graphene content Slurry viscosity (Pa·s) 5％ 73.5 7.5％ 90.5 10％ 98 12.5％ 112.5 15％ 130.5

[0107] Depend on Figure 10 As shown in Table 7, the viscosity of the slurry increases with increasing graphene content. This indicates that, under different conditions, the higher the graphene content in the slurry, the greater its viscosity. A possible reason is that with increasing graphene content, the probability of contact between graphene particles increases, leading to agglomeration and an increase in the graphene flake diameter, thus increasing the slurry viscosity. However, for a slurry to be considered viable, the viscosity must be within a feasible range; it must be greater than 100 Pa·s. Therefore, slurries with graphene contents of 12.5% ​​and 15% have feasible viscosities.

[0108] (3) Morphology analysis of surface coatings for textile ion sensors

[0109] Figure 11 In the middle, from top to bottom, the slurry concentrations are: 15% graphene, 5-25% silk fibroin; Figure 12 In the middle, from top to bottom, the slurry concentrations are: 12.5% ​​graphene, 5-25% silk fibroin; Figure 13 In the middle, from top to bottom, the slurry concentrations are: 10% graphene, 5-25% silk fibroin; Figure 14 In the middle, from top to bottom, the slurry concentrations are: 7.5% graphene, 5-25% silk fibroin; Figure 15 In the middle, from top to bottom, the slurry concentrations are: 5% graphene and 5-25% silk fibroin.

[0110] Depend on Figures 11-15It can be observed that when the graphene content is the same, the coating color becomes increasingly darker with the increase of silk fibroin. This may be because the viscosity of the sizing increases with the increase of silk fibroin, resulting in better adhesion of the sizing to the fabric. When the graphene content is 15%, small particles begin to appear on the coating surface of the fabric as the silk fibroin concentration increases. This is because the sizing concentration is high at this point, close to the saturation concentration for screen printing, making particle phenomena more likely to occur during screen printing. When the graphene content is 12.5%, the coating on the fabric is relatively uniform and thick, with the best effect. Furthermore, the coating effect improves with the increase of silk fibroin concentration, because the sizing concentration is relatively high at this point, resulting in a better screen printing effect. When the graphene content is 5%, the coating effect on the fabric is poor, possibly because there are fewer graphene and silk fibroin in the sizing at this point, resulting in a lower sizing concentration and therefore a poorer effect.

[0111] A 5×5cm textile ion sensor was used, and its surface morphology was observed under high magnification using a scanning electron microscope (SEM). For example... Figure 16 As shown, in order from top to bottom and left to right, the graphene contents of the sizing agents are 5%, 7.5%, 10%, 12.5%, and 15%, respectively, and the silk fibroin content is 25%. Microscopic observation of the fabric surface revealed the following results: The coating density gradually increases with increasing graphene content. When the graphene content is below 7.5%, the coating is relatively sparse, possibly because the graphene content is low and the sizing agent is thin. When the graphene content is between 10% and 12.5%, the coating becomes denser, indicating a significant increase in graphene content. When the graphene content is 15%, large particle agglomerates appear on the coating. This phenomenon may be due to the high graphene content, with the sizing agent concentration approaching the saturation concentration of screen printing, making it difficult for the sizing agent to disperse evenly on the fabric surface, thus leading to agglomeration.

[0112] Depend on Figures 11-16 The comparison shows that the printing effect is best when the paste contains 12.5% ​​graphene and 25% silk fibroin.

[0113] (4) Water resistance of textile ion sensors

[0114] The test subject was a textile ion sensor with a graphene content of 12.5% ​​and a silk fibroin content of 25%. Three pieces of fabric measuring 3*6cm were placed in a beaker, and an appropriate amount of soap flakes were added. The mixture was stirred in a glass cup, and after 30 seconds, the fabric was removed and dried. The conductivity of the dried fabric was then tested again. This process was repeated five times, and the conductivity performance was recorded and compared. The results are shown below. Figure 17 The specific data is shown in Table 8.

[0115] Table 8 Resistance values ​​of fabrics after different washing cycles

[0116] Number of washes Resistance / Ω 0 4588.64 1 4729.48 2 4893.47 3 5099.63 4 5439.48 5 5938.10

[0117] The above results indicate that before three washes, the resistance of the textile ion sensor did not increase significantly, but after three washes, the resistance change increased. This suggests that the sizing agent is suitable for products that are not frequently washed. The main reason is that graphene has a two-dimensional sheet structure of single-layer carbon atoms, lacking other water-soluble groups such as hydroxyl, carboxyl, and heteroatoms. This unique structure makes graphene less water-soluble, and the surface effect of graphene results in a large contact angle with water droplets, leading to poor water wetting. Meanwhile, polyurethane has good adhesion, resulting in better wash resistance.

[0118] (5) Mechanical properties of textile ion sensors

[0119] The mechanical properties of the fabrics before and after screen printing were tested using a tensile strength tester. Samples were cut from the screen-printed fabric and the original fabric, with a length and width of 200*50mm. Five samples were tested in each group, and the average value was taken.

[0120] The tensile strength properties of polyester-cotton fabrics before and after coating were tested using a tensile strength tester. The average breaking strength and elongation at break in the warp and weft directions of the original fabric and the textile ion sensor prepared from the original fabric and 12.5% ​​graphene and 25% virgin silk protein are shown in Tables 9 and 10.

[0121] Table 9 Tensile Results of Original Fabric

[0122]

[0123]

[0124] Note: The CV value, also known as the coefficient of variation, is the ratio of the standard deviation to the mean, indicating the magnitude of the deviation. Generally, a larger CV value indicates greater dispersion and poorer precision in repeated measurements; a smaller CV value indicates smaller dispersion in repeated measurements.

[0125] Table 10 Tensile Results of Textile Ion Sensor

[0126]

[0127] As shown in Tables 9 and 10, the breaking strength of the textile ion sensor is improved in both the warp and weft directions compared to the original fabric. Possible reasons include: 1. Polyurethane is polymerized from isocyanate (monomer) and hydroxyl compounds. Due to the presence of highly polar urethane groups, it is insoluble in non-polar groups and possesses good oil resistance, toughness, abrasion resistance, aging resistance, and adhesion. 2. Graphene is one of the strongest known materials, while also exhibiting excellent toughness and flexibility. Graphene has a theoretical Young's modulus of 1.0 TPa and an inherent tensile strength of 130 GPa. 3. The CN bond length in the -CO-NH- peptide bond of the silk fibroin protein macromolecule is 0.132 nm, which is slightly shorter than the CN single bond length of 0.147 nm but longer than the C=N double bond length of 0.127 nm. This gives the peptide chain some double bond properties and greater rigidity, thus increasing the fabric strength after coating the fabric surface with this sizing agent.

[0128] (6) Bending resistance

[0129] A 10*10cm textile ion sensor was used to test its bending resistance at different angles. Bending was performed 100, 200, 300, 400, 500, 600, 700, 800, 900, and 1000 times at 45°, 90°, 135°, and 180° respectively. The resistance of the samples after each bending was then measured to analyze their bending resistance at different angles.

[0130] The data obtained in the experiment are summarized as follows:

[0131] (1) Data for 45° bend as follows Figure 18 As shown, the corresponding specific data is shown in Table 11.

[0132] Table 11 45° Bending Data

[0133] Number of bends Resistance / Ω 0 27906.1 100 28493.5 200 29484.9 300 30629.8 400 31514.1 500 31151.1 600 31457.7 700 32122.4 800 32108.1 900 32204.5 1000 32611.2

[0134] (2) 90° bending data as follows Figure 19 As shown, the corresponding specific data is shown in Table 12.

[0135] Table 11 90° Bending Data

[0136]

[0137]

[0138] (3) The data for the 135° bend are as follows: Figure 20 The specific data is shown in Table 13.

[0139] Table 13 135° Bending Data

[0140] frequency Resistance / Ω 0 27906.1 100 27843.4 200 27743.7 300 29974.5 400 29485.4 500 30853.5 600 31934.5 700 31942.4 800 32583.5 900 32983.5 1000 32649.7

[0141] (4) The data for 180° bending are as follows Figure 21 The specific data is shown in Table 14.

[0142] Table 14 180° Bending Data

[0143]

[0144]

[0145] like Figures 18-21 As shown in Tables 11-14, the resistance of the textile ion sensor fluctuates slightly with increasing bending frequency, but generally shows an upward trend. This indicates that, under different conditions, the more bending cycles, the higher the resistance of the textile ion sensor, and the worse the ion sensing performance of the slurry. Among the four different bending angles, a 90° bend has the greatest impact on the resistance of the textile ion sensor, while a 180° bend has the least impact. A possible reason is that bending causes the coating to peel off the substrate, creating gaps between the continuous graphene layers, thus reducing conductivity.

[0146] In summary, based on the performance tests of the ion sensing paste and the textile ion sensor after screen printing, the following conclusions are drawn:

[0147] (1) The slurry prepared from graphene, silk fibroin and polyurethane solution has the function of ion sensing.

[0148] (2) Among acidic, neutral and alkaline urinary protein solutions, the alkaline urinary protein solution has the best sensing effect, and the ion sensing effect of the slurry is best when the graphene content is 12.5% ​​and the silk fibroin content is 25%.

[0149] (3) The strength of the fabric after screen printing (i.e., the textile ion sensor) is improved and the fabric has good bending resistance, but the coating is suitable for fabrics that are not frequently washed.

[0150] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An ion-sensing slurry for detecting urinary protein, characterized in that, It includes graphene, waterborne polyurethane, and silk fibroin; the mass of the silk fibroin is 5-25% of the total mass of graphene and waterborne polyurethane; the mass of the graphene is 5-15% of the total mass of graphene and waterborne polyurethane.

2. The ion-sensing slurry according to claim 1, characterized in that, The mass of the graphene is 12.5 to 15% of the total mass of the graphene and waterborne polyurethane.

3. The ion-sensing slurry according to claim 1 or 2, characterized in that, The mass of the silk fibroin is 25% of the total mass of graphene and waterborne polyurethane.

4. A method for preparing the ion-sensing slurry according to any one of claims 1 to 3, characterized in that, Includes the following steps: Graphene powder is dissolved in aqueous polyurethane, and the resulting solution is mixed with silk fibroin to obtain the ion sensing slurry.

5. The preparation method according to claim 4, characterized in that, The dissolution and mixing are carried out under stirring conditions.

6. A textile ion sensor, characterized in that, It includes a fabric and an ion sensing layer located on the surface of the fabric; the ion sensing layer is formed from the ion sensing slurry according to any one of claims 1 to 3 or the ion sensing slurry prepared by the preparation method according to any one of claims 4 to 5.

7. The method for preparing the textile ion sensor according to claim 6, characterized in that, Includes the following steps: The ion-sensing paste is printed onto the surface of the fabric and dried to obtain the textile ion sensor.

8. The preparation method according to claim 7, characterized in that, The printing process includes screen printing.

9. The preparation method according to claim 7, characterized in that, The drying temperature is 60~100℃.

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