Diffusion-driven specific adhesive hydrogel materials, methods of making, and uses thereof

Abstract

The present disclosure is a diffusion-driven specific adhesion hydrogel material, a preparation method and applications thereof, and belongs to the technical field of hydrogels. The main components of the hydrogel material include monomers, solvents, cross-linking agents and cationic components; the monomers form a monomer solution with the solvents, and the monomer solution is mixed with the cross-linking agent and the cationic component, and then is fully cross-linked and polymerized by heating to form the hydrogel material. The present disclosure utilizes the self-reinforcing effect of the tough adhesion and the adhesion strength that presents time progression caused by the cationic component diffusion at the interface of the hydrogel, significantly improves the mechanical properties of the hydrogel material, improves the fracture toughness of the hydrogel material, and endows the hydrogel material with frost resistance and environmental tolerance characteristics. The reaction conditions in the preparation method are mild, the operation is convenient, specific and high-strength bonding between hydrogels can be achieved, and the present disclosure has a wide application prospect in the fields of intelligent adhesion, wearable devices and soft robots, and provides a new idea for designing high-performance and intelligent gel adhesives.

Description

[0001] This application is a divisional application. The parent application number is 202111008138.2, the application date is August 30, 2021, and the title is: Diffusion-driven specific adhesion hydrogel material, preparation method and application thereof. Technical Field

[0002] This disclosure relates to a diffusion-driven specific adhesion hydrogel material, its preparation method, and its application, belonging to the field of hydrogel technology. Background Technology

[0003] The application and development of adhesive hydrogel materials have attracted widespread attention in many emerging fields, including soft machines, wearable sensors, microfluidics, functional coatings, smart responsive materials, and bioengineering. Achieving robust hydrogel-substrate adhesion is crucial in practical applications. However, the adhesion of water-rich hydrogel materials is challenging due to the susceptibility of the adhesion interface to hydration. In recent years, various strategies have been designed to achieve hydrogel adhesion. On the one hand, based on biomimetic concepts such as mussels, sticky fish, comb jellies, and octopuses, many adhesive hydrogels have been proposed from a structural and material perspective. These hydrogels achieve rapid and repeatable adhesion to various substrate materials through covalent bonds, hydrogen bonds, electrostatic interactions, dynamic chemical bonds, self-hydrophobicity, and solvent displacement. On the other hand, methods such as surface modification and topological bonding have been developed to obtain high-strength adhesion between hydrogels and substrates. Furthermore, hydrogel adhesion can be triggered by external stimuli such as pH, temperature, mechanical forces, magnetic fields, and photothermal effects using stitched polymer networks, and even on-demand deadhesion can be achieved.

[0004] While revolutionary progress has been made in hydrogel adhesion research, there are still shortcomings in the study of hydrogel-to-hydrogel adhesion. First, the adhesion efficiency between hydrogels needs further improvement, and achieving ideal adhesion strength values ​​typically requires a considerable amount of time. Taking topological adhesion as an example, adhesion efficiency is highly dependent on factors such as the pore size and chemical composition of the hydrogel material. If the hydrogel substrate contains a dense cross-linked network, such as crystalline regions, highly hydrophobic bodies, or highly entangled chains, polymer diffusion will be strongly inhibited, leading to a significant reduction in adhesion strength and efficiency. Second, hydrogel-to-hydrogel adhesion usually occurs under mild conditions; extreme conditions, such as temperatures below 0°C or prolonged exposure to air, can cause the gel to freeze or suffer severe dehydration, resulting in adhesion failure. Finally, it is worth noting that current research on hydrogel-to-hydrogel adhesion mechanisms, based on interfacial interactions and polymer diffusion, is spontaneous and uncontrollable. Despite the development of on-demand deadhesion strategies, precise control of hydrogel adhesion strength remains difficult. Therefore, achieving robust, efficient, and controllable hydrogel-to-hydrogel adhesion remains a challenge. Summary of the Invention

[0005] This disclosure aims to provide a diffusion-driven specific adhesion hydrogel material, its preparation method, and its application, to achieve efficient and tunable adhesion between hydrogels.

[0006] To achieve the above objectives, this disclosure provides a diffusion-driven specific adhesion hydrogel material, the main components of which include monomers, solvents, crosslinking agents, and cationic components, wherein: the monomers and the solvents form a monomer solution, and the monomer solution is mixed with the crosslinking agent and the cationic components and then heated to fully crosslink and polymerize to form a hydrogel material; the monomer is acrylic acid, the solvent is deionized water, and the specific adhesion hydrogel material is prepared by the following method: an acrylic acid solution is prepared by using deionized water and acrylic acid; the acrylic acid solution is mixed with the crosslinking agent and the cationic components, and then heated to fully crosslink and polymerize to form a hydrogel material.

[0007] In the above scheme, the monomer is acrylic acid, the solvent is deionized water, and the mass fraction of the acrylic acid solution formed by the monomer and the solvent is 10-20 wt.%.

[0008] In the above scheme, the crosslinking agent is ferric chloride, and the mass ratio of ferric chloride to acrylic acid is 1:10.

[0009] In the above scheme, the mass ratio of the crosslinking agent, the cationic component and the formed hydrogel material is 1:5:15.

[0010] In the above scheme, the cationic component is sodium chloride, potassium chloride or ammonium chloride.

[0011] In the above scheme, the diffusion of the cationic component at the interface of the hydrogel material promotes physical interaction, enabling the hydrogel material to achieve rapid and ultra-high strength adhesion with various gel substrate materials. The adhesion strength exhibits a self-reinforcing effect and adjustable performance as the spatiotemporal dynamics of ion diffusion evolve.

[0012] In the above scheme, the hydrogel and the gel substrate material undergo rapid and specific adhesion in less than 5 seconds; the self-reinforcing time of the interfacial adhesion strength is less than 24 hours; the adjustable interfacial adhesion strength is manifested in obtaining an adhesion strength range of 0.1 MPa to 1.2 MPa according to different hydrated ion concentrations and ion diffusion times; the diffusion-driven ultra-strong interfacial adhesion strength can reach 1.2 MPa when the material is bonded to the gel substrate, and the interfacial adhesion energy exceeds 3000 J / m². -2 .

[0013] To achieve the above objectives, this disclosure also provides a method for preparing a diffusion-driven specific adhesion hydrogel material, comprising: preparing an acrylic acid solution using deionized water and acrylic acid; mixing the acrylic acid solution with a crosslinking agent and a cationic component, and then heating to fully crosslink and polymerize to form a hydrogel material.

[0014] In the above scheme, the mass fraction of the acrylic acid solution is 10-20 wt.%.

[0015] In the above scheme, the crosslinking agent is ferric chloride, and the mass ratio of ferric chloride to acrylic acid is 1:10.

[0016] In the above scheme, the mass ratio of the crosslinking agent, the cationic component and the formed hydrogel material is 1:5:15.

[0017] In the above scheme, the cationic component is sodium chloride, potassium chloride or ammonium chloride.

[0018] In the above scheme, the cationic component diffuses at the interface of the hydrogel material to achieve interfacial adhesion and precisely control the adhesion interface, so that the hydrogel material can quickly and specifically bond with various gel substrate materials, and the bonding strength of the interface exhibits self-reinforcing phenomenon within a specific time.

[0019] In the above scheme, the hydrogel and the gel substrate material undergo rapid and specific adhesion in less than 5 seconds; the self-reinforcing time of the interfacial adhesion strength is less than 24 hours; the interfacial adhesion strength is in situ enhanced by the diffusion of the cationic component in the hydrogel material; the maximum adhesion strength between the hydrogel and the gel substrate material is 1.2 MPa, and the adhesion energy is 3000 J / m². -2 .

[0020] To achieve the above objectives, this disclosure also provides an application of diffusion-driven specific adhesion hydrogel material in the fields of smart adhesion, wearable devices, soft robots, microfluidics, functional coatings, smart responsive materials, and bioengineering.

[0021] In the above scheme, the hydrogel material serves as an injectable, high-performance, and intelligent hydrogel adhesive.

[0022] As can be seen from the above technical solution, this disclosure has the following beneficial effects:

[0023] 1. The diffusion-driven specific adhesion hydrogel material and its preparation method provided in this disclosure, wherein the main components of the hydrogel material include monomers, solvents, crosslinking agents and cationic components, utilize the self-reinforcing effect of the cationic components diffusing at the hydrogel interface to promote tough adhesion and the adhesion strength increasing over time, which significantly improves the mechanical properties of the hydrogel material, enhances the fracture toughness of the hydrogel material, and endows the hydrogel material with antifreeze and environmental tolerance properties, thereby achieving efficient and controllable adhesion between hydrogels.

[0024] 2. The diffusion-driven specific adhesion hydrogel material and its preparation method provided in this disclosure, wherein monomers, solvents, crosslinking agents, and cationic components are fully crosslinked under reaction conditions to obtain a hydrogel with good tensile strength and freeze-thaw resistance. When adhering to gel substrate materials, a strong bond can be rapidly formed without any external stimuli such as ultraviolet radiation, pressure, or pH. Furthermore, high-strength adhesion can be achieved even under mild conditions, low-temperature environments, and adverse environments with long-term exposure to air. Moreover, this hydrogel can achieve rapid and effective (<5 seconds) adhesion to various gel substrates.

[0025] 3. The diffusion-driven specific adhesion hydrogel material and its preparation method provided in this disclosure overcome the problems of easy hydration and stability of the adhesion interface by using entropy-driven (i.e. diffusion-driven) diffusion of cationic components to promote the formation of interfacial interactions. The cationic components not only enhance the mechanical properties of the hydrogel, but also significantly improve the adhesion performance of the hydrogel interface.

[0026] 4. The diffusion-driven specific adhesion hydrogel material and its preparation method provided in this disclosure achieve a self-reinforcing effect at the adhesion interface through entropy-driven diffusion of cationic components, resulting in a maximum adhesion strength of 1.2 MPa and an adhesion energy of 3000 J / m² between the hydrogel and a tough gel substrate. -2 .

[0027] 5. The diffusion-driven specific adhesion hydrogel material and its preparation method provided in this disclosure have mild reaction conditions and are easy to operate. They can achieve specific and high-strength adhesion between hydrogels. They can also achieve rapid and high-strength adhesion between hydrogels in adverse environments such as low temperature and long-term exposure to air.

[0028] 6. The diffusion-driven specific adhesion hydrogel material provided in this disclosure has excellent adhesion properties, high tensile strength, good antifreeze properties and environmental tolerance properties, and has potential application prospects in the fields of smart gel adhesives, wearable devices and soft robots.

[0029] 7. The diffusion-driven specific adhesion hydrogel materials and their adhesion mechanisms disclosed herein provide new ideas for designing high-performance and smart gel adhesives. Attached Figure Description

[0030] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0031] Figure 1 This is a flowchart of a hydrogel preparation method according to an embodiment of the present disclosure.

[0032] Figure 2 This is a schematic diagram of a hydrogel preparation method according to an embodiment of the present disclosure.

[0033] Figure 3 The diagram shows the mechanical properties of the hydrogel according to Embodiment 4 of this disclosure. (a) Tensile curves of hydrogel materials with different cation concentrations; (b) Tensile curves of hydrogel materials with different concentrations of crosslinking agent components; (c) Thermal analysis diagrams of hydrogel materials with different cation concentrations; (d) Environmental resistance of hydrogel materials with different cation concentrations.

[0034] Figure 4 This is a schematic diagram of the hydrogel interface adhesion mechanism driven by the diffusion of cationic components according to Example 5 of this disclosure.

[0035] Figure 5 This is a schematic diagram of the specific adhesion properties of the hydrogel at different times according to Embodiment 5 of this disclosure.

[0036] Figure 6 This is a schematic diagram of the adhesion strength and adhesion energy of the hydrogel adhesion interface under different environmental conditions according to Embodiment 5 of this disclosure. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0038] This disclosure provides a diffusion-driven specific adhesion hydrogel material, its preparation method, and its application. The hydrogel material mainly comprises monomers, solvents, crosslinking agents, and cationic components. The monomers and solvents form a monomer solution, which is then mixed with the crosslinking agent and the cationic components and subjected to heating for complete crosslinking and polymerization to form the hydrogel material. Utilizing the self-reinforcing effect of the cationic component diffusion at the hydrogel interface, which promotes strong adhesion and increases adhesion strength over time, the mechanical properties of the hydrogel material are significantly improved, its fracture toughness is enhanced, and it is endowed with freeze-thaw resistance and environmental tolerance, achieving efficient and controllable adhesion between hydrogels.

[0039] In this embodiment, the monomer may be acrylic acid, and the solvent component may be high-purity water, such as deionized water. The mass fraction of the acrylic acid solution formed by the monomer and the solvent is 10-20 wt.%. The crosslinking agent may be ferric chloride, and the mass ratio of ferric chloride to acrylic acid is 1:10. The mass ratio of the crosslinking agent, the cationic component, and the formed hydrogel material is 1:5:15. The cationic component may be sodium chloride, potassium chloride, or ammonium chloride.

[0040] In this embodiment, the cationic component diffuses at the interface of the hydrogel material to achieve interfacial adhesion and precisely control the adhesion interface, enabling the hydrogel material to rapidly and specifically bond with various gel substrate materials, and the interfacial adhesion strength exhibits self-reinforcing behavior within a specific time. The rapid and specific adhesion between the hydrogel and the gel substrate material takes less than 5 seconds; the self-reinforcing time of the interfacial adhesion strength is less than 24 hours; the interfacial adhesion strength is in situ enhanced by the diffusion of the cationic component in the hydrogel material; the maximum adhesion strength between the hydrogel and the gel substrate material is 1.2 MPa, and the adhesion energy is 3000 J / m². -2 .

[0041] In the embodiments disclosed herein, the hydrogel material, as an injectable, high-performance, and intelligent hydrogel adhesive, has potential applications in fields such as smart adhesion, wearable devices, soft robots, microfluidics, functional coatings, smart responsive materials, and bioengineering, providing new ideas for designing high-performance and intelligent gel adhesives.

[0042] In this embodiment of the invention, the method for preparing the diffusion-driven specific adhesion hydrogel material includes: preparing an acrylic acid solution using deionized water and acrylic acid; mixing the acrylic acid solution with a crosslinking agent and a cationic component, and then heating to fully crosslink and polymerize to form a hydrogel material.

[0043] In this preparation method embodiment, the mass fraction of the acrylic acid solution is 10-20 wt.%, the crosslinking agent is ferric chloride, and the mass ratio of ferric chloride to acrylic acid is 1:10; the cationic component is sodium chloride, potassium chloride, or ammonium chloride, and the mass ratio of the crosslinking agent, the cationic component, and the formed hydrogel material is 1:5:15.

[0044] The following detailed description, in conjunction with the accompanying drawings and embodiments, illustrates the diffusion-driven specific adhesion hydrogel materials, their preparation methods, and their applications provided in this disclosure.

[0045] Example 1

[0046] This disclosure provides a method for preparing a diffusion-driven specific adhesion hydrogel material, such as... Figure 1 and Figure 2 As shown. 1g of acrylic acid was added to 10ml of deionized water and stirred thoroughly with a magnetic stirrer at room temperature to obtain an acrylic acid solution. Then, 0.01g of initiator, 0.5g of ferric chloride, and 2.5g of sodium chloride were added successively, and stirring was continued until the initiator, crosslinking agent, and cationic component were uniformly dispersed in the acrylic acid solution. The solution was poured into a mold and placed in a high-temperature water bath for 30 minutes to allow the polymer network to fully crosslink, resulting in a hydrogel material with good mechanical properties.

[0047] Example 2

[0048] This disclosure provides a method for preparing a diffusion-driven specific adhesion hydrogel material, such as... Figure 1 and Figure 2 As shown, 1g of acrylic acid was added to 10ml of deionized water and stirred thoroughly with a magnetic stirrer at room temperature to obtain an acrylic acid solution. Then, 0.01g of initiator, 1g of ferric chloride, and 2.5g of potassium chloride were added successively, and stirring was continued until the initiator, crosslinking agent, and cationic component were uniformly dispersed in the acrylic acid solution. The solution was poured into a mold and placed in a high-temperature water bath for 30 minutes to allow the polymer network to fully crosslink, resulting in a hydrogel material with good mechanical properties.

[0049] Example 3

[0050] This disclosure provides a method for preparing a diffusion-driven specific adhesion hydrogel material, such as... Figure 1 and Figure 2 As shown. 1g of acrylic acid was added to 10ml of deionized water and stirred thoroughly with a magnetic stirrer at room temperature to obtain an acrylic acid solution. Then, 0.01g of initiator, 1.5g of ferric chloride, and 2.5g of ammonium chloride were added successively, and stirring was continued until the initiator, crosslinking agent, and cationic component were uniformly dispersed in the acrylic acid solution. The solution was poured into a mold and placed in a high-temperature water bath for 30 minutes to allow the polymer network to fully crosslink, resulting in a hydrogel material with good mechanical properties.

[0051] Example 4

[0052] This disclosure provides a diffusion-driven specific adhesion hydrogel material, and its mechanical property test is described as follows: A hydrogel sample with a diameter of 3 mm and a length of 10 mm was taken and its mechanical properties were tested using a universal testing machine. Figure 3The mechanical properties of the hydrogels prepared in Example 1 above are shown. (a) is a tensile curve of the hydrogels with and without cationic components. Compared to the hydrogel without cationic components, the tensile strength of the hydrogel material containing cationic components is significantly improved, reaching 3 MPa at a tensile rate of 100 mm / min. (b) is a tensile curve of hydrogel materials containing different concentrations of ferric chloride. As shown, the hydrogel material exhibits the best mechanical properties when the mass percentage of ferric chloride is 1.5%. (c) is a thermal analysis diagram of the hydrogels with and without cationic components. The samples were first cooled from room temperature to -80°C, and then thermally heated at 10°C / min. -1 The hydrogel was heated to 50°C at a rate of [missing value]. Characterization showed that the hydrogel containing the cationic component exhibited low-temperature resistance (~-20°C), remaining stretchable even at low temperatures with tensile stress and strain closely similar to those at room temperature. (d) shows a schematic diagram of the environmental resistance of hydrogels with and without cationic components. The hydrogel was exposed to air (30% humidity, 20% temperature), and its weight was measured every 24 hours to evaluate its environmental resistance. Compared to hydrogels without cationic components, the environmental resistance of hydrogel materials containing cationic components was significantly improved.

[0053] Example 5:

[0054] This disclosure provides a diffusion-driven specific adhesion hydrogel material, and its adhesion performance test is described as follows: A hydrogel sample with dimensions of 10mm × 20mm × 3mm and a hydrogel substrate material were taken, and the adhesion strength was tested. For each test, the actual adhesion area on the substrate was measured separately to ensure the accuracy of the measurement data. The bonded sample was subjected to a tensile-shear test on a universal testing machine (tensile rate: 50mm min). -1 Adhesion strength is recorded as maximum force divided by the actual bonded area. Hydrogel samples measuring 10mm × 70mm × 3mm and hydrogel substrate materials were used to test adhesion energy. A rigid polycarbonate film (125μm thick) was adhered to the back of each sample as a support to prevent gel deformation. The 180° peel test was performed using a universal testing machine at room temperature and 10mm min. -1 Measurements were taken at a tensile speed. The free end of the sample was fixed to the machine's chuck. Adhesion energy was calculated as twice the average platform force divided by the sample width. The error of each data point was tested using at least five different samples to obtain an average value with a standard deviation.

[0055] Figure 4 A schematic diagram of the hydrogel interface adhesion mechanism driven by cationic component diffusion is shown. To overcome the problems of easy hydration and stability of the adhesion interface, entropy-driven diffusion of cationic components is used to promote the formation of interfacial interactions, thereby achieving tough interfacial adhesion. Figure 5 The specific adhesion properties of the hydrogel, tested in Example 4, are shown at two different time points: <5 seconds and 24 hours. First, the hydrogel described in this disclosure does not exhibit adhesion to substrate materials such as glass, metal, and PDMS; however, it specifically adheres to the hydrogel substrate material. Second, the hydrogel described in this disclosure can achieve rapid adhesion to the hydrogel substrate material (<5 seconds), and the interfacial adhesion strength exhibits a self-reinforcing effect over time, reaching a high adhesion strength at 24 hours. Finally, hydrogel substrate materials with poor mechanical properties fail during the adhesion strength test, meaning the interfacial strength is higher than the fracture toughness of the hydrogel substrate material itself, further demonstrating that the hydrogel described in this disclosure can achieve a tough adhesion interface with the hydrogel substrate material.

[0056] Figure 6 The diagram shows the adhesion strength and adhesion energy of the hydrogel adhesion interface obtained in Example 4 under different environmental conditions. Figure 6 As shown, the hydrogel described in this disclosure adheres to a tough hydrogel substrate material to form an ultra-high strength adhesive interface. The interfacial adhesion strength can reach 1.2 MPa after 24 hours, and the interfacial adhesion energy can reach 3000 J / m. -2 Even in adverse conditions such as low temperatures and prolonged exposure to air, high-strength adhesion can be achieved, and the hydrogel adhesion can be maintained for 48 hours or even longer. These adhesion performance results demonstrate that the specific adhesive hydrogel material described in this disclosure can achieve rapid, tough, freeze-resistant, and environmentally resistant adhesion between hydrogels.

[0057] The specific embodiments described above further illustrate the purpose, technical solutions, and beneficial effects of this disclosure. It should be understood that the above descriptions are merely specific embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A diffusion-driven specific adhesion hydrogel material, the main components of which consist of monomers, solvents, crosslinking agents, and cationic components, wherein: The monomer and the solvent form a monomer solution, and the monomer solution is mixed with the crosslinking agent and the cationic component and then heated to fully crosslink and polymerize to form a hydrogel material. The monomer is acrylic acid, the solvent is deionized water, the crosslinking agent is ferric chloride, and the cationic component is sodium chloride, potassium chloride, or ammonium chloride. The cationic component diffuses at the interface of the hydrogel material to achieve interfacial adhesion and precisely control the adhesion interface, enabling the hydrogel material to bond rapidly and specifically with various gel substrate materials, and the bonding strength of the interface exhibits self-reinforcing phenomenon within a specific time. The specific adhesive hydrogel material is prepared by the following method: an acrylic solution is prepared by mixing deionized water and acrylic acid; the acrylic solution is mixed with a crosslinking agent and a cationic component, and then heated to fully crosslink and polymerize to form a hydrogel material, wherein the mass ratio of the crosslinking agent, the cationic component and the formed hydrogel material is 1:5:15; The hydrogel and the gel substrate material bond rapidly and specifically in less than 5 seconds; the self-strengthening time of the interfacial bond strength is less than 24 hours; the interfacial bond strength is in situ enhanced by the diffusion of the cationic component in the hydrogel material; the maximum adhesion strength between the hydrogel and the gel substrate material is 1.2 MPa, and the adhesion energy is 3000 J / m². -2 .

2. The diffusion-driven specific adhesion hydrogel material according to claim 1, wherein, The mass fraction of the acrylic acid solution formed by the monomer and the solvent is 10~20 wt.%.

3. The diffusion-driven specific adhesion hydrogel material according to claim 2, wherein, The mass ratio of ferric chloride to acrylic acid is 1:

10.

4. A method for preparing a diffusion-driven specific adhesion hydrogel material according to any one of claims 1 to 3, comprising: An acrylic acid solution was prepared using deionized water and acrylic acid. After mixing the acrylic solution with a crosslinking agent and cationic components, the mixture is heated to fully crosslink and polymerize, forming a hydrogel material.

5. The method for preparing the diffusion-driven specific adhesion hydrogel material according to claim 4, wherein, The acrylic acid solution has a mass fraction of 10~20 wt.%.

6. The method for preparing the diffusion-driven specific adhesion hydrogel material according to claim 4, wherein, The crosslinking agent is ferric chloride, and the mass ratio of ferric chloride to acrylic acid is 1:

10.

7. The method for preparing the diffusion-driven specific adhesion hydrogel material according to claim 4, wherein, The mass ratio of the crosslinking agent, the cationic component, and the formed hydrogel material is 1:5:

15.

8. The method for preparing the diffusion-driven specific adhesion hydrogel material according to claim 4, wherein, The cationic component is sodium chloride, potassium chloride, or ammonium chloride.

9. The method for preparing the diffusion-driven specific adhesion hydrogel material according to claim 4, wherein, The cationic component diffuses at the interface of the hydrogel material to achieve interfacial adhesion and precisely control the adhesion interface, enabling the hydrogel material to bond rapidly and specifically with various gel substrate materials, and the bonding strength of the interface exhibits self-reinforcing phenomenon within a specific time.

10. The method for preparing the diffusion-driven specific adhesion hydrogel material according to claim 9, wherein, The hydrogel bonds rapidly and specifically to the gel substrate material in less than 5 seconds. The self-strengthening time of the bonding strength of the interface is less than 24 hours; The adhesion strength at the interface is enhanced in situ as the cationic component diffuses into the hydrogel material. The maximum adhesion strength between the hydrogel and the gel substrate material is 1.2 MPa, and the adhesion energy is 3000 J / m². -2 .

11. The application of a diffusion-driven specific adhesion hydrogel material according to any one of claims 1 to 3 in the fields of smart adhesion, wearable devices, soft robots, microfluidics, functional coatings, smart responsive materials and bioengineering.

12. The application according to claim 11, wherein, The hydrogel material serves as an injectable, high-performance, and intelligent hydrogel adhesive.

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