A starch-based biomimetic impact-resistant gel and a preparation method and application thereof

Abstract

The present application relates to a kind of based on starch biomimetic impact gel and its preparation method and application, preparation method includes: the solution of silane grafting modified starch is mixed with ionic solution, gel component is mixed, layered processing, gelation reaction, obtain.Compared with prior art, the preparation process of the present application is simple and efficient, material is cheap and easy to obtain, the gel with biomimetic structure prepared has obvious mechanical property difference, the outer hard phase can resist dynamic impact load, the inner soft phase provides good energy dissipation capacity, thereby reducing the blunt injury to human body, showing excellent impact resistance and buffering effect, meanwhile, the gel also has good sensing performance, can be assembled into skin protection device, has important significance in soft armor, human-computer interaction, wearable monitoring equipment field.

Description

Technical Field

[0001] This invention belongs to the field of gel materials technology, and relates to a starch-based biomimetic impact-resistant gel, its preparation method and application. Background Technology

[0002] With the advancement of technology and social development, the requirements for material performance are increasing across all industries, especially the demand for material durability and safety. Impact loads exist in human activities such as daily life, sports, automotive transportation, aerospace, and military operations, posing a potential threat to personal safety. Protective equipment, as a crucial barrier to ensure human life, must possess sufficient impact protection performance. The impact resistance of rigid protective materials generally stems from their high stiffness and hardness; however, this inherently makes them lack flexibility, hindering their ability to effectively dissipate energy and protect objects with complex shapes or dynamic deformation characteristics.

[0003] In recent years, with the advancement of science and technology, some soft protective materials have been developed. Flexible protective materials have excellent deformability and good energy absorption capacity. However, since mechanical strength and energy dissipation capacity are often inversely related, they are difficult to resist large dynamic impact loads. At the same time, the local deformation effect caused by the impact can still cause blunt damage to the protected object. Therefore, there is an urgent need for a strategy to construct flexible protective materials that can synergistically resist impact and achieve good energy dissipation.

[0004] Inspired by the impact-resistant structures and protective mechanisms of organisms in nature, such as shells, bones, and crustaceans, these organisms possess structural gradients, consisting of a hard outer layer and a flexible inner layer. The hard outer layer directly resists impact loads, while the flexible inner layer absorbs high energy, acting as a deformable buffer layer to stabilize the structure. Therefore, developing a material with a hard outer layer and a flexible inner layer to reduce deformation effects during impact can achieve excellent impact load resistance and good protective buffering effects, preventing secondary injuries to the human body, and has great application potential.

[0005] Hydrogels are a class of materials with a three-dimensional cross-linked network structure. Through structural and functional design, they can achieve excellent strain response, good mechanical compliance, and tunable electrical conductivity, and have broad application prospects in fields such as body indicator monitoring, soft robots, and human-computer interaction.

[0006] Prior art CN114835931A discloses an interface-enhanced multilayer composite conductive gel and its preparation method. The multilayer composite conductive gel comprises n gel layers and n-1 interface layers, which are alternately stacked, with the layers arranged sequentially along the stacking direction as a first gel layer, a first interface layer, a second gel layer, a second interface layer, ..., the (n-1)th interface layer, and the nth gel layer, where n is an integer greater than or equal to 2. In this invention, the interface layer serves as the bonding interface between the gel layers, constructing interlocking structural units between adjacent gel layers. This results in the multilayer composite conductive gel exhibiting excellent tensile properties, good tensile strength, good elastic modulus, and high toughness, as well as excellent interface stability and good fatigue resistance. As a tensile strain sensor, it also possesses good conductivity, sensitive strain sensing performance, a wide strain response range, and excellent response stability.

[0007] Currently, hydrogel materials have been extensively studied in the fields of monitoring and sensing of life signals and human movement, but there are few reports on their application in shock-resistant sensing that integrates monitoring and protection. Summary of the Invention

[0008] The purpose of this invention is to provide a starch-based biomimetic impact-resistant gel that integrates impact protection and monitoring, along with its preparation method and applications. The gel material prepared using a biomimetic strategy exhibits different structural morphologies within the gel due to the sedimentation of starch particles, resulting in a distinct layered structure that is hard on the outside and soft on the inside. This unique biomimetic structure endows the inner and outer sides of the gel with significantly different mechanical properties, effectively combining the characteristics of hard and soft materials. This overcomes the shortcomings of existing protective materials, meeting the flexibility requirements of wearable devices while also satisfying the impact resistance requirements of protective materials. It exhibits a significant force attenuation effect, protecting fragile items and human safety from damage. Furthermore, this biomimetic gel possesses good electrical conductivity, demonstrating excellent sensing sensitivity and good stability.

[0009] The objective of this invention can be achieved through the following technical solutions:

[0010] The first aspect of the present invention provides a method for preparing a starch-based biomimetic impact-resistant gel, comprising: mixing a solution of silane-grafted modified starch with an ionic solution and a gelling component, performing a layering process, and a gelling reaction to obtain the gel.

[0011] In some specific embodiments, the preparation method of the silane-grafted modified starch includes: mixing starch and a silane coupling agent in water and reacting them to obtain the desired result.

[0012] In some preferred embodiments, the silane coupling agent is propyl 3-(trimethoxysilyl)methacrylate;

[0013] The amount of starch added is 30%-50% of the weight of water, and the amount of silane coupling agent added is 3%-5% of the weight of the silane-grafted modified starch solution. The reaction temperature is room temperature, and the reaction time is 24-48 hours.

[0014] In some specific embodiments, the mass ratio of starch to silane coupling agent is 30:4.35.

[0015] In some preferred embodiments, the reaction temperature is room temperature and the reaction time is 24–48 h.

[0016] In some specific embodiments, the ionic liquid is selected from one of imidazole acetate, imidazole chloride, and imidazole bromide; preferably 1-ethyl-3-methylimidazole acetate.

[0017] The gelling component includes a monomer, a crosslinking agent, and a thermal initiator. The monomer is acrylamide, the crosslinking agent is chondroitin sulfate methacrylamide, and the thermal initiator is potassium persulfate.

[0018] In some specific embodiments, the amount of the ionic liquid added is 10%-20% of the weight of the silane-grafted modified starch solution, the amount of the monomer added is 30-40% of the weight of the silane-grafted modified starch solution, the amount of the crosslinking agent added is 0.1%-1% of the weight of the silane-grafted modified starch solution, and the amount of the thermal initiator added is 0.5%-1% of the weight of the silane-grafted modified starch solution.

[0019] In some specific embodiments, the feeding ratio of the silane-grafted modified starch solution, ionic liquid, monomer, crosslinking agent, and thermal initiator is 10mL:1g:4g:100mg:50mg, wherein the amount of the silane-grafted modified starch solution is calculated as a modified starch solution with a mass fraction of 50%.

[0020] In some specific embodiments, the stratification process includes static stratification, with the static temperature at room temperature and the static time being 1-2 hours.

[0021] In some specific embodiments, the gelation reaction is carried out at a temperature of 70-80°C and a reaction time of 20-40 minutes.

[0022] In some specific embodiments, the preparation method of starch-based biomimetic impact-resistant gel includes the following steps:

[0023] (1) Use silane coupling agent to modify starch granules, graft double bonds on the starch surface to enhance the compatibility of starch granules in gel.

[0024] (2) The modified starch obtained in step (1) is mixed with ionic liquid and gelling component, and the mixture is shaken thoroughly to prepare a uniform gel precursor solution;

[0025] (3) The precursor liquid obtained in step (2) is left to stand, gravity induces stratification, and gels under thermal initiation conditions. After cooling, a biomimetic gel with an outer hard and inner soft structure with impact resistance is obtained.

[0026] A second aspect of the present invention provides a starch-based biomimetic impact-resistant gel, which is prepared by the method described above.

[0027] A third aspect of the present invention provides an application of the starch-based biomimetic shock-resistant gel as described above, including using the starch-based biomimetic shock-resistant gel to prepare epidermal protective devices.

[0028] The process conditions described in this invention represent the optimal preparation conditions. This invention modifies starch using a silane coupling agent, grafting double bonds to enhance the compatibility of starch particles in the hydrogel. Starch itself consists of micron-sized particles, making it difficult to integrate well with the gel system, resulting in low toughness and high brittleness—a key issue limiting the application of starch-based hydrogels. Modification with a silane coupling agent allows it to form a more robust network with polymers, improving the tensile modulus and toughness of the gel.

[0029] This invention induces starch granules to settle under gravity by allowing the precursor solution to stand, resulting in a gel with a distinct layered structure, exhibiting a hard lower layer and a soft upper layer. The chosen thermal initiation gelation temperature of 70°C is used to induce gelatinization of the starch granules during gelation. Gelatinization causes the starch granules to gradually expand, disrupting their ordered crystalline structure. Amylose leaches from the granules and participates in the gel network, forming a stable network with the polymers. Cooling at room temperature for 24 hours after gelation allows the starch to retrograde. Amorphous starch paste, amylose, and amylopectin recrystallize through hydrogen bonds, further enhancing the mechanical strength of the lower gel layer. This results in a significant difference in mechanical properties between the soft and hard gel layers, thus achieving a good synergistic effect in resisting impact and energy dissipation.

[0030] This invention incorporates ionic liquids during gel preparation. Ionic liquids are salts with melting points below 100°C. As a green solvent, they possess excellent water retention, high ionic conductivity, freeze resistance, and thermal stability. Ionic liquids such as imidazole acetate, imidazole chloride, and imidazole bromide, composed of imidazole cations and anions with strong hydrogen bonding capabilities, can bind to the hydroxyl groups of polysaccharide molecules, exhibiting excellent solubility for natural polymers such as starch. This not only further enhances the compatibility of starch in the gel but also endows the gel with good electrical conductivity, making it suitable for use as a strain / pressure sensor. Therefore, in practical applications, this gel can be assembled into a good skin protection device to achieve synergistic monitoring and protection against impact forces, thereby enabling applications in fields such as soft robotics and human-computer interaction.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1) Compared with traditional impact-resistant materials, the biomimetic impact-resistant gel prepared by this invention can solve the contradiction between the inability of hard materials to dissipate energy and the inability of soft materials to prevent penetration, effectively combining hard and soft materials into a whole, and achieving the integration of structure and performance.

[0033] 2) Hydrogels with a hard outer layer and a soft inner layer, developed using biomimetic structure inspiration, have high impact resistance and energy absorption capacity. The hard outer layer can effectively resist dynamic impact loads, while the soft inner layer can efficiently absorb and disperse impact energy, thus playing a protective and buffering role and effectively reducing blunt damage to objects.

[0034] 3) Compared with traditional impact-resistant materials, the biomimetic impact-resistant gel prepared by this invention not only has structural advantages, but also endows the gel with good sensing properties, which can synergistically realize the monitoring and protection of impact force, and make up for the problem of the relatively single performance of traditional materials.

[0035] 4) By adjusting the amount of starch added, the ratio of the soft and hard gel layers can be controlled, thereby enabling customized design of protective materials and achieving excellent protection and cushioning effects.

[0036] 5) The preparation process of the present invention is simple and effective, and the raw materials are inexpensive and readily available. Attached Figure Description

[0037] Figure 1 This is a schematic diagram illustrating the preparation of the starch-based biomimetic impact-resistant gel in this embodiment.

[0038] Figure 2(a) Tensile stress-strain curves, (b) Young's modulus and toughness, and (c) tensile comparison diagrams of acrylamide (AAm), acrylamide / starch raw material (AAm / Starch), and acrylamide / modified starch solution (AAm / St-MA) hydrogels, as examples.

[0039] Figure 3 Scanning electron microscope images of the starch raw material (Starch), modified starch solution (St-MA), and the hard and soft layers of the starch-based biomimetic impact-resistant gel, as shown in the example.

[0040] Figure 4 Polarized light microscope images of the starch raw material (Starch), modified starch solution (St-MA), and the hard and soft layers of the starch-based biomimetic impact-resistant gel, as shown in the example.

[0041] Figure 5 X-ray diffraction patterns of the starch raw material (Starch), modified starch solution (St-MA), and the hard and soft layers of the starch-based biomimetic impact-resistant gel in the embodiment;

[0042] Figure 6 Two-dimensional wide-angle X-ray scattering images of the starch raw material (Starch), modified starch solution (St-MA), and the hard and soft layers of the starch-based biomimetic impact-resistant gel used in the embodiment;

[0043] Figure 7 Raman spectra of the starch raw material (Starch), modified starch solution (St-MA), and the hard and soft layers of the starch-based biomimetic impact-resistant gel in the example.

[0044] Figure 8 Infrared spectrum of starch-based biomimetic impact-resistant gel as an example;

[0045] Figure 9 The layered puncture, tensile, and compressive stress-strain curves and soft-hard layer modulus diagrams of the starch-based biomimetic impact-resistant gel used in this embodiment are shown.

[0046] Figure 10 A schematic diagram illustrating how starch-based biomimetic impact-resistant gel protects glass and eggs from damage, as shown in the embodiment.

[0047] Figure 11The impact force test diagrams of the starch-based biomimetic impact-resistant gel for the example are as follows: (a) Bar graph of peak impact force of gels with different soft and hard layer ratios, (b) Impact force-time curve of gel with a soft and hard layer ratio of 1:1 at different drop heights, and (c) Bar graph of impact force of gel with a soft and hard layer ratio of 1:1 and other common protective materials at a drop height of 1m.

[0048] Figure 12 The following are examples of the split Hopkinson bar curves of the starch-based biomimetic impact-resistant gel: (a) Schematic diagram of the split Hopkinson bar test system, (b) Impact stress-strain curves of the hardened gel at different strain rates, and (c) Bar charts of maximum stress and corresponding impact toughness at different strain rates.

[0049] Figure 13 The following are the sensing performance diagrams of the starch-based biomimetic impact-resistant gel used in the embodiment: (a) Schematic diagram of a pressure sensor assembled by sandwiching the gel between two copper foils; (b) GF value of the gel pressure sensor; (c) ΔR / R0 resistance change curves within the strain range of 1%-5% and (d) 5%-30%; (e) ΔR / R0 change curves caused by a 100g ball falling from different heights; (f) ΔR / R0 change curves caused by balls of different weights falling from a height of 1m.

[0050] Figure 14 This is a schematic diagram of the structure of a starch-based biomimetic impact-resistant gel used in an embodiment. Detailed Implementation

[0051] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0052] In the following embodiments, unless otherwise specified, the raw materials, reagents or processing techniques are all conventional commercial products or conventional processing techniques in the art.

[0053] In the following embodiments,

[0054] The method for characterizing the puncture modulus includes: puncturing a 1 mm thick sheet-like hydrogel sample with a 2 mm diameter and 7 cm length traction needle at a speed of 60 mm / min.

[0055] The characterization method of Young's modulus includes: cutting the hydrogel sample into strips (50 mm in length, 8 mm in width, and 1 mm in thickness) and stretching them at a rate of 50 mm / min until the breaking point.

[0056] The method for characterizing the compressive modulus includes cutting the hydrogel sample into a cylindrical shape (14 mm in diameter and 10 mm in thickness) and compressing it at a speed of 5 mm / min until 95% of the strain is reached.

[0057] The above elastic moduli were all calculated by the slope of the fitted straight line in the linear range (5%-15%) of the stress-strain curve.

[0058] The method for characterizing the impact resistance of gels involves placing a gel sample on a pressure sensor (RDF-DP), with the soft layer attached to the sensor (i.e., soft layer below, hard layer above). A steel ball (100g) is dropped freely from a height of 1m, impacting the 3mm thick sample. The force-time curve and peak impact force received by the sensor at the bottom of the sample are analyzed from the collected data. The frequency signal is 100kHz.

[0059] Example

[0060] A method for preparing a starch-based biomimetic impact-resistant gel includes the following steps:

[0061] Preparation of modified starch: Add 30g starch to 60mL of deionized water, stir thoroughly and place on a magnetic stirrer with a speed of 300rpm. Then slowly add 4.35g silane coupling agent (3-(trimethoxysilyl)propyl methacrylate, TMSPMA) to the starch solution. After reacting at room temperature for 24h, centrifuge the solution to wash away unreacted silane coupling agent to obtain modified starch.

[0062] Preparation of a biomimetic hard-on-soft-on-the-inner layered hydrogel: 10 mL of 50% modified starch solution (St-MA) was weighed and added to a 50 mL centrifuge tube and dispersed evenly. Then, 1 g of 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]), 4 g of acrylamide (AAm), 100 mg of chondroitin sulfate (CSMA), and 50 mg of potassium persulfate (KPS) were added. The mixture was vortexed and then shaken for 10 min to ensure thorough mixing. The prepared precursor solution was then poured into a designated mold and allowed to stand for 1 h to allow for layering. Finally, the mixture was placed in a 70℃ oven for thermal initiation gelation for 30 min. A schematic diagram is shown below. Figure 1 As shown, the result is as follows. Figure 14 The material shown is an impact-resistant gel material with a biomimetic hard outer and soft inner layered structure (forming upper and lower layers during the static process, with the upper layer being soft as a skin-friendly inner layer and the lower layer being hard as an outer reinforcing layer).

[0063] like Figure 2As shown, firstly, the tensile test curves indicate that, compared to starch, the addition of modified starch can effectively improve the tensile properties of the gel. The modified St-MA particles can participate more effectively in the polymer network through partial bonding, enhancing the compatibility of starch particles in the hydrogel. Compared to AAm / starch, the tensile modulus and toughness of AAm / St-MA gel increased from 0.4 MPa / 4.81 MJ / m², respectively. -3 Increased to 0.71 MPa / 12.97 MJ m -3 The stretched physical images also show that the gel with modified starch has a greater elongation at break, which indicates that modified starch can build a more robust gel network.

[0064] like Figure 3 As shown, the microstructure was characterized. Both starch and modified starch exhibit granular shapes. However, under 70℃ thermal induction, the granular morphology of starch is disrupted. The image reveals that the soft layer gel exhibits a typical porous network structure, while the tough layer not only possesses the gel's inherent network structure but also clearly shows embedded semi-gelatinized starch granules. This demonstrates the distribution of starch within the gel. Furthermore, two distinct structures exist within the starch: a crystalline structure and an amorphous structure. These two structures differ in density and refractive index, representing its growth ring structure, which produces a polarized cross under a polarizing microscope. Figure 4 As shown, both starch and modified starch have polarized crosses. However, during gelatinization, the polarized crosses of starch gradually decrease and eventually disappear. In the gel soft layer, the polarized crosses are basically gone, while in the tough layer, starch granules exist and exhibit polarized cross phenomena.

[0065] Its crystal structure was further characterized by XRD and WAXS, as follows: Figure 5 and Figure 6 As shown, starch is a C-type crystal with obvious characteristic peaks at 15, 17, 19, and 22°, and exhibits a clear diffraction ring from the inside out. In the soft layer of the gel, the characteristic peaks of starch completely disappear, and the diffraction rings are basically gone. The characteristic peaks are present in the tough layer, but the peak values ​​are reduced, although the crystal structure is still there. This indicates that the small amount of starch in the soft layer inside the gel will be completely gelatinized, while the large amount of starch in the tough layer due to the gravity sedimentation step will be partially gelatinized during thermal gelation.

[0066] like Figure 7 and 8As shown, the mechanism of action within the gel was analyzed using Raman and infrared spectroscopy. The decrease in peak intensity in the Raman spectrum and the continuous shift of the starch-OH peak in the infrared spectrum towards lower wavenumbers with the addition of ionic liquids and acrylamide indicate that the internal mechanism of action within the gel primarily involves the interaction between the -OH group of starch and the -NH2 group in acrylamide, and the -COO group in [Emim][OAc]. - Hydrogen bonding occurs.

[0067] Next, the quasi-static mechanical properties of the gel were characterized. Figure 9 It was found that the gel exhibited significant differences in mechanical properties between its soft and hard phases, with a 74-fold difference in puncture modulus, a 112.5-fold difference in Young's modulus, and a 33.52-fold difference in compressive modulus. The hard phase possessed higher mechanical strength. The gel's protective effect on fragile items was then investigated. A 535g steel ball was dropped freely from a height of 1.5m, impacting a glass substrate coated with the gel. Simultaneously, the breakage of a fragile object (a raw egg) dropped freely from a height of 1m onto the gel surface was also investigated. The results are as follows... Figure 10 As shown, both Tough and Tough+Soft gels provide good protection for glass plates due to their tough hard layers. However, gels without a soft layer cannot protect raw eggs from breakage. This indicates that the soft layer can buffer the impact by deforming. In the case of hydrogels with only a soft layer, the low modulus makes them ineffective, and both the glass and the raw egg will break. This further demonstrates the advantage of this hard-outer-soft-inner structure in terms of impact resistance.

[0068] Next, by assembling a force sensor with a ball drop apparatus, a 100g ball was dropped freely from a height of 1m to impact a gel placed on the sensor surface. The impact force dissipated by the gel was investigated, and the results are as follows: Figure 11As shown in the figure. Compared with the blank control group without gel as a protective material, gels with different soft-hard phase ratios all provided a certain buffering effect. Specifically, the mass fractions of the gel-modified starch solutions with T:S = 1:1, T:S = 1:2, and T:S = 2:1 were 50%, 30%, and 60%, respectively. Without any protective material, the sensor measured the impact force of the falling steel ball as 4531.95 ± 15.77 N. Under conditions with only the tough and soft hydrogel layers, the impact forces measured were 1363.5 ± 12.02 and 2290.5 ± 180.31 N, respectively. When the soft-tough layer ratio T:S was adjusted to 2:1, 1:2, and 1:1, the measured impact forces were 1011.5 ± 74.25, 1182.5 ± 24.75, and 885.1 ± 49.49 N, respectively. In summary, the synergistic effect of the soft and hard layers of the hydrogel results in better impact resistance. It resists impact loads through the outer tough layer, while the inner soft layer further deforms and dissipates energy. As the drop height changes, the peak impact force increases with height, but the layered hydrogel with a T:S ratio of 1:1 still exhibits excellent impact protection performance, attenuating 82% of the impact force at a drop height of 1m. Subsequently, impact force comparison tests were conducted using various commonly used protective materials at the same impact height. It was found that the peak impact force of the layered hydrogel with an outer hard layer and an inner soft layer is superior to that of commonly used protective materials, exhibiting the smallest peak impact force and demonstrating excellent impact resistance and a significant force attenuation effect.

[0069] The ability of the gel hard phase to resist impact loads was demonstrated using a split Hopkinson bar, and the dynamic impact properties of the gel were evaluated. All specimens were 8 mm in diameter and 4 mm thick, meeting the aspect ratio standard of 1:2. The strain rate range was 1000 s⁻¹. -1 up to 5000s -1 The impact stress-strain curves of the gel hard layer were tested at different strain rates. Figure 12 As shown, the gel exhibits typical impact behavior, with impact stress and strain gradually increasing with increasing impact velocity, reaching a maximum at a strain rate of 5000 s⁻¹. -1 At this point, the hydrogel exhibited an impact stress of 86.83 ± 1.66 MPa and an impact toughness of 20.09 ± 0.32 MJ / m. -3 This indicates that its tough outer layer can effectively resist external impacts.

[0070] Finally, sensor tests were conducted, such as... Figure 13As shown, a resistive pressure sensor was constructed by sandwiching it between conductive copper tapes. The sensing performance of the gel was tested by measuring the relative resistance change (ΔR / R0) under different strains. The results show that the maximum GF value can reach ≈12.04 under small pressure strain, indicating that the soft-hard layered hydrogel has high sensitivity under small strain. Cyclic compression tests were conducted under small strain (1%-5%), medium strain (5%-30%), and falling ball impact conditions. It can be seen that the resistance change of the hydrogel has good stability. It can be repeatedly compressed under small strain and large impact stress, exhibiting good pressure-sensitive stability and impact sensing capability. It can sense and distinguish different impact forces without being damaged. Compared with the piezoresistive sensors reported in previous literature, it has a unique and wider detection range.

[0071] In summary, the preparation process of this invention is simple and efficient, and the materials are inexpensive and readily available. The resulting biomimetic gel exhibits significant differences in mechanical properties. It can resist dynamic impact loads through the outer hard phase and provide good energy dissipation capacity through the inner soft phase, thereby reducing blunt force trauma to the human body and demonstrating excellent impact resistance and buffering effect. At the same time, the gel also has good sensing properties and can be assembled into skin protection devices, which is of great significance in the fields of soft armor, human-computer interaction, and wearable monitoring devices.

[0072] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a starch-based biomimetic impact-resistant gel, characterized in that, include: A solution of silane-grafted modified starch is mixed with an ionic liquid and a gelling component, and then subjected to a layered treatment and gelling reaction to obtain the desired product. The ionic liquid is selected from one of imidazole acetate, imidazole chloride, and imidazole bromide. The gelling component includes a monomer, a crosslinking agent, and a thermal initiator. The monomer is acrylamide, the crosslinking agent is chondroitin sulfate methacrylamide, and the thermal initiator is potassium persulfate. The amount of the ionic liquid added is 10%-20% of the weight of the silane-grafted modified starch solution, the amount of the monomer added is 30-40% of the weight of the silane-grafted modified starch solution, the amount of the crosslinking agent added is 0.1%-1% of the weight of the silane-grafted modified starch solution, and the amount of the thermal initiator added is 0.5%-1% of the weight of the silane-grafted modified starch solution. The layering process includes static layering, with the static temperature at room temperature and the static time being 1-2 hours; In the gelation reaction, the reaction temperature is 70-80℃.

2. The preparation method of starch-based biomimetic impact-resistant gel according to claim 1, characterized in that, The method for preparing the silane-grafted modified starch includes: mixing starch and a silane coupling agent in water and reacting them to obtain the desired result.

3. The preparation method of starch-based biomimetic impact-resistant gel according to claim 2, characterized in that, The silane coupling agent is propyl 3-(trimethoxysilyl)methacrylate; The amount of starch added is 30%-50% of the weight of water, and the amount of silane coupling agent added is 3%-5% of the weight of the silane-grafted modified starch solution. The reaction temperature is room temperature, and the reaction time is 24-48 h.

4. The preparation method of starch-based biomimetic impact-resistant gel according to claim 1, characterized in that, The ionic liquid is 1-ethyl-3-methylimidazolium acetate.

5. The method for preparing starch-based biomimetic impact-resistant gel according to claim 1, characterized in that, The gelation reaction takes 20-40 minutes.

6. A starch-based biomimetic impact-resistant gel, characterized in that, It is prepared by the method described in any one of claims 1 to 5.

7. An application of the starch-based biomimetic impact-resistant gel as described in claim 6, characterized in that, The starch-based biomimetic impact-resistant gel is used to prepare epidermal protective devices.

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