Processing method of tough, transparent and adhesive supramolecular hydrogel

Abstract

The invention belongs to but not limited to the technical field of hydrogel, and particularly relates to a processing method of tough, transparent and adhesive supramolecular hydrogel, which comprises the following steps: step 1, preparing a supramolecular hydrogel precursor with a specific shape; step 2, dissolving the prepared precursor in water; step 3, freezing under a low-temperature condition; step 4, standing the frozen supramolecular hydrogel in air or dry inert gas; step 5, cutting and folding the obtained hydrogel, and processing the hydrogel into another shape; and 6, swelling the processed hydrogel in an acid-containing nutrient solution to obtain the final hydrogel. By adopting a supramolecular strategy and utilizing a high-density supramolecular network formed by tannic acid (TA) and polyvinyl alcohol (PVA), the mechanical property, transparency and adhesiveness of the hydrogel are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to but is not limited to the field of hydrogel technology, and in particular to a method for processing a tough, transparent and adherent supramolecular hydrogel. Background Art

[0002] In the field of materials science, hydrogels are widely used in many fields such as biomedicine, electronic devices and soft robotics due to their high water content, softness and biocompatibility. However, traditional hydrogels usually have problems such as poor mechanical properties, high brittleness and difficult processing, which limit their widespread use in practical applications. In order to solve these problems, researchers are committed to developing hydrogel materials with excellent mechanical properties, transparency and adhesion to broaden their application scenarios.

[0003] In recent years, supramolecular hydrogels have attracted widespread attention due to their network structures formed by non-covalent bonds (such as hydrogen bonds, van der Waals forces, π-π interactions, etc.). Supramolecular interactions not only give hydrogels good repairability and self-healing ability, but also enable them to be processed and reshaped at low energy consumption. At the same time, by optimizing the design of supramolecular forces, the mechanical properties of the material can be enhanced, its adhesion can be improved, and a certain degree of transparency can be given to it, which makes supramolecular hydrogels show great application potential in the fields of biomedical adhesives, flexible electronic devices and smart materials.

[0004] Currently, a variety of methods for preparing supramolecular hydrogels have been proposed, such as hydrogel systems formed by multiple hydrogen bond interactions or host-guest chemistry. However, these hydrogels often have deficiencies in adhesion or mechanical properties, and it is difficult to meet the requirements of toughness, transparency and adhesion at the same time. For example, some hydrogels are prone to breakage under high stress, or their transparency is greatly affected by the material structure. In addition, existing processing methods are usually complex and inefficient, making it difficult to achieve large-scale application of hydrogels.

[0005] In view of the above analysis, the technical problems that urgently need to be solved in the prior art are: how to develop a supramolecular hydrogel that has toughness, transparency and adhesion at the same time, and optimize its processing method to simplify the preparation process and improve efficiency. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides a method for processing tough, transparent and adhesive supramolecular hydrogels. By utilizing supramolecular interactions and special network design, the material can exhibit excellent mechanical properties and adhesion while maintaining good transparency, thereby providing a wider range of choices for practical applications.

[0007] The present invention is achieved by a method for processing a tough, transparent and adherent supramolecular hydrogel, comprising:

[0008] Step 1, preparing a supramolecular hydrogel precursor of a specific shape;

[0009] Step 2, dissolving the prepared precursor in water;

[0010] Step 3, freezing under low temperature conditions;

[0011] Step 4, allowing the frozen supramolecular hydrogel to stand in air or dry inert gas;

[0012] Step 5, cutting and folding the obtained hydrogel to process it into another shape;

[0013] Step six, swelling the processed hydrogel in an acid-containing nutrient solution to obtain the final hydrogel.

[0014] Furthermore, the supramolecular hydrogel polymer precursors prepared in step 1 include polysaccharides, polyvinyl alcohol, peptides, polyethylene glycol, and polylactic acid. The supramolecular hydrogel polymer is generated by heating under the action of the precursors and aqueous solution.

[0015] Furthermore, the precursor includes one or more of lipopolysaccharide, Peptides Ubiquitin, polylactic acid (Mw~60,000), PVA (Mw~88000), PVA 1799, PVA (Mw~61000); and the heating temperature is 10℃-80℃.

[0016] Furthermore, in the preparation method of supramolecular hydrogel in step 1, the molar ratio of the precursor to the aqueous solution is 9:1, 5:1, 3:1, and 0.5:1.

[0017] Furthermore, the water dissolution time in step 2 is 1 hour to 24 hours.

[0018] Furthermore, in step three, the operation is performed at low temperature, and the low-temperature manufacturing tools used are tools such as freezers or refrigerators.

[0019] Furthermore, in step 4, the inert drying gas is one or more of nitrogen, helium, and argon, and is dried at room temperature.

[0020] Furthermore, the operation in step five is carried out at room temperature, and the cutting tools used are tools such as scissors or a cutting machine.

[0021] Furthermore, the organic acid in step six comprises one or more of adipic acid, sebacic acid, suberic acid, and dodecanedioic acid.

[0022] Furthermore, in the preparation method of the acid-containing nutrient solution described in step six, the molar ratio of the organic acid to the aqueous solution is 99:1, 99.9:0.1, and 99.99:0.01.

[0023] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0024] First, the present invention proposes a supramolecular strategy to prepare tough, transparent and adhesive hydrogels. This method uses tannic acid (TA) as the core material to form a high-density supramolecular network, thereby giving the hydrogel excellent mechanical properties and multifunctional properties. First, polyvinyl alcohol (PVA) hydrogel is prepared by freeze-thaw cycles and then soaked in a high-concentration tannic acid solution. The polyphenol groups in TA interact with the hydroxyl groups in the PVA chains to construct a tight supramolecular network. At the same time, the high osmotic pressure of the TA solution further compresses the PVA chains, forming a hydrogen-bonded network structure with high toughness.

[0025] This high-density supramolecular network gives the hydrogel excellent mechanical properties, making it extremely resistant to rupture under stress. In addition, the compact network structure eliminates phase boundaries, thereby enhancing the transparency of the hydrogel and allowing light to pass through smoothly. At the same time, the abundant hydroxyl and phenol groups in the hydrogel give it good adhesion, allowing it to tightly bond to the surfaces of a variety of substrates. The hydrogel prepared by this method is not only tough, transparent and adhesive, but also has broad application prospects in the biomedical field (such as surgical sutures and contact lenses) in the future because both PVA and TA have good biocompatibility and degradability.

[0026] The present invention adopts a supramolecular strategy and utilizes a high-density supramolecular network formed by tannic acid (TA) and polyvinyl alcohol (PVA) to significantly improve the mechanical properties, transparency and adhesion of the hydrogel. First, supramolecular interactions give the hydrogel excellent toughness, and the dense hydrogen bond network enables the material to maintain structural stability under high stress and avoid rupture. In addition, the compact structure of the supramolecular network eliminates the phase boundary inside the material, thereby greatly improving the transparency of the hydrogel and ensuring the smooth passage of light.

[0027] Through the processing method of the present invention, the hydrogel also has excellent adhesion. The polyphenol groups in TA interact with the hydroxyl groups in the PVA chain to form a rich hydrogen bond network, which enables the hydrogel to achieve stable adhesion on the surfaces of different substrates. This property greatly broadens the application range of the hydrogel, especially in the fields of biomedicine and flexible electronic devices.

[0028] Compared with the prior art, the present invention adopts a simple and environmentally friendly hydrogel processing method, avoiding high temperature, complex chemical treatment or the use of organic solvents. By using low-cost biomaterials such as PVA and TA, the present invention not only improves the processability of the material, but also has good biocompatibility and degradability, which meets the requirements of current environmental protection policies. In addition, the reversibility of the supramolecular network gives the material good self-repairing ability, further extending its service life.

[0029] Therefore, the present invention has broad application prospects in biomedical devices, electronic component packaging and other application fields requiring high-performance materials.

[0030] Second, as auxiliary evidence of the inventiveness of the claims of the present invention, it is also reflected in the following important aspects:

[0031] (1) The expected benefits and commercial value of the technical solution of the present invention after transformation are:

[0032] The supramolecular hydrogel technology of the present invention has a wide range of commercial application potential due to its unique toughness, transparency and adhesion, especially in high value-added fields such as biomedicine, flexible electronic devices and smart materials. The expected benefits after transformation include the following aspects: 1. Medical field: hydrogels can be widely used in various clinical treatments as surgical suture materials, wound dressings and contact lenses and other medical devices due to their good biocompatibility and mechanical properties, and are expected to significantly improve surgical safety and patient comfort. In addition, the degradability and self-healing properties of hydrogels can reduce the need for secondary surgery or replacement of materials and reduce medical costs. 2. Electronic devices: Since the hydrogel of the present invention has both transparency and adhesion and self-healing ability, it can be used as a packaging material for flexible electronic components. Its transparency makes it suitable for use in high-tech products such as touch screens, waterproof electronic devices, sensors, etc., and has extremely high commercial value. 3. Sustainable development: The present invention uses green materials (such as PVA and TA), whose low cost and environmentally friendly characteristics are in line with the current global environmental protection trend. It is expected to occupy a place in the degradable material market and has a good market prospect.

[0033] By combining with the relevant industrial chain, the hydrogel material of the present invention can not only meet the market demand, but also significantly increase the added value of the product, bringing long-term economic benefits to the relevant enterprises.

[0034] (2) The technical solution of the present invention fills the technical gap in the industry at home and abroad:

[0035] Existing hydrogel technology often cannot strike a balance between toughness, transparency and adhesion, and the processing technology is complicated, making it difficult to promote on a large scale in practical applications. Although there are many studies on supramolecular hydrogel materials at home and abroad, most of them focus on optimizing a single performance, such as improving transparency or adhesion, while ignoring the overall improvement of mechanical properties. The present invention, by introducing a high-density supramolecular network formed by tannic acid and PVA, achieves the simultaneous improvement of these three key properties for the first time, and adopts a simple low-temperature processing method, which greatly simplifies the preparation process.

[0036] This technology fills the gap in the comprehensive performance of mechanical properties, transparency and adhesion in the hydrogel field at home and abroad, and provides a new direction for the research and development and application of multifunctional hydrogel materials.

[0037] (3) The technical solution of the present invention solves the technical problems that people have been eager to solve but have never been able to solve successfully:

[0038] For a long time, researchers have been seeking a hydrogel material that is tough, transparent and adhesive, and can simultaneously meet the application requirements of different fields (such as biomedicine and electronic devices). However, traditional hydrogel materials are prone to breakage under high stress, their transparency is limited by the material structure, and their adhesion is difficult to meet the requirements for application on a variety of substrate surfaces. Through supramolecular interactions, the present invention effectively overcomes these technical difficulties and develops a hydrogel that integrates the three major properties, successfully filling the gap in this field for many years.

[0039] (4) The technical solution of the present invention overcomes technical prejudice:

[0040] The traditional view is that the softness and high water content of hydrogels will inevitably lead to poor mechanical properties, and the pursuit of high mechanical properties usually sacrifices the transparency or adhesion of the material. The present invention breaks through this technical prejudice. By rationally designing the supramolecular network structure, the toughness and transparency of the hydrogel are significantly improved while maintaining a high water content, and the adhesion of the material is improved by introducing tannic acid. This innovative design breaks the trade-off between traditional material properties and provides a new idea for the research and development of hydrogels.

[0041] Third, the present invention solves the deficiencies of supramolecular hydrogels in the prior art in terms of toughness, transparency and adhesion. Traditional hydrogel materials often have problems such as fragile structure, low transparency and easy cracking, especially when subjected to mechanical stress or external environmental changes, the durability and adaptability of hydrogels are poor. In addition, it is difficult for traditional hydrogels to maintain high adhesion, which limits their application in medicine and industry and makes them unable to play a long-term role in complex environments. These problems seriously restrict the effect and service life of hydrogels in practical applications.

[0042] The present invention solves these key problems through unique processing steps, significantly improving the toughness and transparency of the hydrogel. The method of low-temperature freezing and slow thawing is adopted to form a microscopic pore structure inside the hydrogel, which enhances the elasticity and tensile strength of the material and greatly improves its toughness. The molecular arrangement during the freezing process further improves the transparency of the hydrogel, enabling it to meet the application requirements with high transparency requirements. At the same time, this structural design enables the hydrogel to remain stable when subjected to mechanical stress, overcoming the defect of easy brittle fracture of traditional materials.

[0043] In terms of adhesion, the present invention greatly enhances the intermolecular hydrogen bonds and cross-linking degree of the hydrogel through the swelling step of the acid-containing nutrient solution, making it have stronger adhesion and biocompatibility. This innovation enables the hydrogel to better adhere to the surfaces of different materials in multiple fields such as medicine, electronics, and packaging, especially in humid environments and human body surface applications. Compared with traditional hydrogels, the products of the present invention can maintain high adhesion for a long time, significantly improving their industrial applicability and reliability.

[0044] The technical solution of the present invention significantly improves the physical properties and application breadth of hydrogels, and demonstrates superior technological progress in industrial applications. While maintaining the transparency and high strength of the hydrogel, the method achieves good forming and processing performance, enabling it to adapt to a variety of complex forms and application environments, opening up a new direction for the industrial application of hydrogel materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a sample preparation and processing flow chart provided by an embodiment of the present invention;

[0046] Figure 2 It is a schematic diagram of the transparency change of the swollen sample in the TA solution in the implementation cases 1, 2, 3, and 4 provided in the embodiments of the present invention;

[0047] Figure 3 is an adhesion force-displacement curve diagram of the swollen samples in TA solution in Examples 1, 2, 3, and 4 provided in the embodiments of the present invention;

[0048] Figure 4 Schematic diagram showing the adhesion of the swollen samples in Examples 1, 2, 3, and 4 provided in the embodiments of the present invention;

[0049] Figure 5 These are actual sample diagrams of implementation cases 1, 2, 3 and 4 provided in the embodiments of the present invention. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0051] like Figure 1 As shown, the simple environmentally friendly processing method of supramolecular hydrogel provided by the embodiment of the present invention comprises the following steps:

[0052] Step 1, preparing a supramolecular hydrogel precursor of a specific shape;

[0053] Step 2, dissolving the prepared precursor in water;

[0054] Step 3, freezing under low temperature conditions;

[0055] Step 4, allowing the frozen supramolecular hydrogel to stand in air or dry inert gas;

[0056] Step 5, cutting and folding the obtained hydrogel to process it into another shape;

[0057] Step six, swelling the processed hydrogel in an acid-containing nutrient solution to obtain the final hydrogel.

[0058] The present invention provides a method for processing a tough, transparent and adhesive supramolecular hydrogel, which comprises multiple steps to achieve its characteristics. First, in step 1, a supramolecular hydrogel precursor of a specific shape is prepared, which determines the initial shape of the final hydrogel. The precursor can be realized in various shapes, such as block, sheet, etc., through a pre-designed mold, which provides a basis for subsequent dissolution and molding. This step ensures that the supramolecular hydrogel has a stable precursor structure, laying the foundation for the final physical properties.

[0059] In step 2, the prepared supramolecular hydrogel precursor is placed in water to dissolve, so that the precursor gradually forms a uniform gel solution. The dissolution process in this step is critical. Through appropriate dissolution time and temperature control, the molecular chains are ensured to be evenly dispersed in water. This uniform dispersion helps the subsequent gel formation and structural stability, while ensuring that the final hydrogel is transparent and free of bubbles.

[0060] Step three uses low-temperature freezing treatment to quickly freeze the dissolved supramolecular hydrogel solution. Low-temperature freezing can form a microscopic pore structure inside the hydrogel, thereby improving the toughness of the hydrogel. After freezing, the water in the gel will partially crystallize, bringing about an orderly arrangement of the internal structure, making the hydrogel have better elasticity and toughness under the action of external forces. This step is the core step to give the hydrogel tough properties.

[0061] Then in step 4, the frozen supramolecular hydrogel is placed in air or dry inert gas to gradually thaw and form a hydrogel with a certain shape. During this process, the static air or inert gas environment causes the internal water of the hydrogel to evaporate slowly, further strengthening the intermolecular forces of the hydrogel and improving its adhesion ability. This slow thawing method effectively avoids excessive changes in the internal structure, allowing the gel to maintain its shape while obtaining better transparency and stability.

[0062] In step five, the obtained hydrogel is subjected to processing operations such as cutting and folding to adjust it to the desired shape. This step is highly operational and can cut and shape the hydrogel into various forms according to different application requirements to meet specific adhesion or covering requirements. By performing secondary processing on the hydrogel, it can be more flexibly adapted to various complex application scenarios.

[0063] Finally, in step six, the processed hydrogel is placed in an acid-containing nutrient solution for swelling treatment, so that it absorbs the components in the nutrient solution to achieve the predetermined strength and adhesion. The acidic environment makes the supramolecular chains of the hydrogel more active, increases the hydrogen bonding between molecules and the degree of cross-linking of the molecular chains, thereby significantly improving its adhesion and durability. The resulting hydrogel is tough, transparent, and has strong adhesion, and can be widely used in medical, industrial, and bioengineering fields.

[0064] In the present invention, firstly, a polymer and water are mixed, and then heated and stirred at a certain temperature to obtain a supramolecular hydrogel precursor. Then, the hydrogel precursor is treated with ultrasound at room temperature to remove bubbles. After a certain period of time, the hydrogel precursor is taken out of the ultrasound instrument. Then, the mixed solution is stored in a freezer and frozen, and then thawed in air or inert gas at room temperature. After repeating this freeze-thaw cycle, a hydrogel is obtained. Through the same freeze-thaw process, prepared hydrogels with different weight percentages can be prepared.

[0065] To prepare the final hydrogel, a certain volume of the preparatory hydrogel is soaked in an organic acid solution. After a few days, the final hydrogel is formed.

[0066] The present invention preferably selects PVA (Mw-88000) as the polymer, tannic acid as the organic acid, ultrapure water as the solvent, the concentration of PVA dissolved in water is 20wt%, and the content of tannic acid dissolved in water is 1mol%.

[0067] The present invention preferably has a temperature of 95°C, a heating time of 2 hours, a freezing-thawing cycle number of three times, a freezing temperature of -12°C, and a thawing temperature of 25°C.

[0068] The present invention preferentially uses the strip shape as the shape of the initial sample, thereby demonstrating the toughness, transparency and adhesion properties of the PVA supramolecular hydrogel.

[0069] The present invention preferably selects three freeze-thaw cycles, with a freezing temperature of -12°C, a freezing time of 2 hours, a thawing temperature of 25°C, and a thawing time of 2 hours.

[0070] The present invention preferably selects thawing in dry air.

[0071] The present invention preferably uses 1 mol% tannic acid to swell the prepared hydrogel, and the swelling time is 4 days.

[0072] Polyvinyl alcohol (PVA), with an average molecular weight of 89,000-98,000 and a hydration degree of 99%, was used in all our experiments. Both PVA and tannic acid were purchased from Aladdin Chemical Company and used directly without any further treatment.

[0073] Example 1

[0074] A method for preparing a tough, transparent and adherent supramolecular hydrogel comprises the following steps:

[0075] (1) Dissolve 5 g of PVA polymer in 20 g of deionized water and heat at 80° C. Stir at 350 rpm for 70 minutes to obtain a uniform mixed solution A;

[0076] (2) treating the mixed solution A obtained in step (1) with ultrasound at room temperature for 10 minutes to remove bubbles;

[0077] (3) storing the mixed solution A obtained in step (2) in a freezer at -20°C for 12 hours, and then thawing it at room temperature for 6 hours to obtain a hydrogel prototype;

[0078] (4) Repeating the freeze-thaw cycle three times on the hydrogel prototype obtained in step (3) to obtain the final PVA hydrogel;

[0079] (5) processing the hydrogel sample of step (4) into a PVA hydrogel with a length of 3.5 cm, a width of 2 cm, and a thickness of 0.2 cm;

[0080] (6) The sample obtained in step (5) was sealed and immersed in 20 ml of 1 mol % TA solution for 4 days to form a PVA / TA hydrogel;

[0081] (7) The sample obtained in step (6) was adhered to a Teflon plate and the adhesion was tested.

[0082] Example 2

[0083] A method for preparing a tough, transparent and adherent supramolecular hydrogel comprises the following steps:

[0084] (1) dissolving 5 g of PVA polymer in 20 g of deionized water, heating at 80° C., and stirring at 350 rpm for 70 minutes to obtain a uniform mixed solution A;

[0085] (2) treating the mixed solution A obtained in step (1) with ultrasound at room temperature for 10 minutes to remove bubbles;

[0086] (3) storing the mixed solution A obtained in step (2) in a freezer at -20°C for 12 hours, and then thawing it at room temperature for 6 hours to obtain a hydrogel prototype;

[0087] (4) Repeating the freeze-thaw cycle three times on the hydrogel prototype obtained in step (3) to obtain the final PVA hydrogel;

[0088] (5) processing the hydrogel sample of step (4) into a PVA hydrogel with a length of 3.5 cm, a width of 2 cm, and a thickness of 0.2 cm;

[0089] (6) The sample obtained in step (5) was sealed and immersed in 20 ml of 1 mol % TA solution for 4 days to form a PVA / TA hydrogel;

[0090] (7) Adhere the sample obtained in step (6) to an asbestos board and test the adhesion.

[0091] Example 3

[0092] A method for preparing a tough, transparent and adherent supramolecular hydrogel comprises the following steps:

[0093] (1) dissolving 5 g of PVA polymer in 20 g of deionized water, heating at 80° C., and stirring at 350 rpm for 70 minutes to obtain a uniform mixed solution A;

[0094] (2) treating the mixed solution A obtained in step (1) with ultrasound at room temperature for 10 minutes to remove bubbles;

[0095] (3) storing the mixed solution A obtained in step (2) in a freezer at -20°C for 12 hours, and then thawing it at room temperature for 6 hours to obtain a hydrogel prototype;

[0096] (4) Repeating the freeze-thaw cycle three times on the hydrogel prototype obtained in step (3) to obtain the final PVA hydrogel;

[0097] (5) processing the hydrogel sample of step (4) into a PVA hydrogel with a length of 3.5 cm, a width of 2 cm, and a thickness of 0.2 cm;

[0098] (6) The sample obtained in step (5) was sealed and immersed in 20 ml of 1 mol % TA solution for 4 days to form a PVA / TA hydrogel;

[0099] (7) The sample obtained in step (6) is adhered to a glass plate and the adhesion is tested.

[0100] Example 4

[0101] A method for preparing a tough, transparent and adherent supramolecular hydrogel comprises the following steps:

[0102] (1) dissolving 5 g of PVA polymer in 20 g of deionized water, heating at 80° C., and stirring at 350 rpm for 70 minutes to obtain a uniform mixed solution A;

[0103] (2) treating the mixed solution A obtained in step (1) with ultrasound at room temperature for 10 minutes to remove bubbles;

[0104] (3) storing the mixed solution A obtained in step (2) in a freezer at -20°C for 12 hours, and then thawing it at room temperature for 6 hours to obtain a hydrogel prototype;

[0105] (4) Repeating the freeze-thaw cycle three times on the hydrogel prototype obtained in step (3) to obtain the final PVA hydrogel;

[0106] (5) processing the hydrogel sample of step (4) into a PVA hydrogel with a length of 3.5 cm, a width of 2 cm, and a thickness of 0.2 cm;

[0107] (6) The sample obtained in step (5) was sealed and immersed in 20 ml of 1 mol % TA solution for 4 days to form a PVA / TA hydrogel;

[0108] (7) The sample obtained in step (6) was adhered to an aluminum plate and the adhesion was tested.

[0109] These embodiments demonstrate the diverse applications of tough, transparent and adhesive supramolecular hydrogels in biomedicine, such as articular cartilage restoration, electronic skin, bandages, etc., according to the claims. By adjusting the composition and processing conditions of the polymer, the application of different environmental factors can be achieved, thereby meeting a variety of practical application needs.

[0110] The present invention provides a method for processing a tough, transparent and adhesive supramolecular hydrogel, which has excellent mechanical properties, transparency and adhesion through reasonable material selection and processing steps. The method mainly achieves multiple functionalities of the material by regulating the internal molecular structure and external morphology of the hydrogel, and has broad application prospects, especially in the fields of biomedicine, soft robots, wearable devices, etc.

[0111] 1. Preparation of supramolecular hydrogel precursor: In the first step, a supramolecular hydrogel precursor with a specific shape was prepared by selecting suitable monomers and cross-linking agents. Supramolecular hydrogels rely on weak intermolecular forces (such as hydrogen bonds, van der Waals forces, etc.) to form a network structure. This step ensures that the precursor has a certain morphological stability and lays the foundation for subsequent dissolution and processing.

[0112] 2. Dissolving the precursor in water: In the second step, the prepared precursor is dissolved in water. This process softens the gel structure by destroying some weak intermolecular forces in the precursor, allowing water molecules to enter the network. This step provides good operability for subsequent freezing treatment and morphological reshaping.

[0113] 3. Low-temperature freezing treatment: In the third step, the dissolved hydrogel is placed under low-temperature conditions for freezing. The core function of this step is to make the water molecules in the hydrogel crystallize and leave the supramolecular structure network at low temperatures through freeze-thaw action, further strengthening the intermolecular forces inside the gel, thereby improving its mechanical properties and toughness. The low-temperature freezing process also effectively prevents the gel from shrinking or losing transparency during the static process.

[0114] 4. Standing process: The fourth step is to let the frozen supramolecular hydrogel stand in air or dry inert gas. The standing process allows water molecules to further evaporate from the inside of the material, thereby gradually hardening the hydrogel and stabilizing its structure. Through the inert gas drying process, the gel can be prevented from reacting with moisture or oxygen in the external environment, ensuring that the transparency and adhesion properties of the gel are not affected.

[0115] 5. Cutting and folding of hydrogel: In the fifth step, after the gel has been hardened by standing, it has good deformation and processing capabilities. At this time, the gel can be cut, folded and other mechanical processes to form a specific shape. Since the gel has good toughness and flexibility at this stage, the processed gel shape can maintain good stability and is not easy to break or damage during the folding and cutting process.

[0116] 6. Swelling and nutrient solution treatment: The last step is to swell the processed hydrogel in an acid-containing nutrient solution to restore it to a soft state. This step can further activate the functionality of the hydrogel through the action of the acidic solution, such as enhancing its adhesion properties, improving the flexibility of the material, and enhancing its biocompatibility while maintaining transparency. This step ensures the long-term use and functional realization of the final hydrogel in biomedical or other application scenarios.

[0117] Through this series of steps, the processing method of the present invention ensures that the supramolecular hydrogel has the characteristics of toughness, transparency and adhesion, and can be prepared into complex shapes that meet the needs of practical applications through a simple processing process. This method not only simplifies the preparation process of the hydrogel, but also greatly improves the application breadth and stability of the material.

[0118] Example 1: Supramolecular hydrogels for wearable devices

[0119] 1. Precursor preparation: The synthesized polymer containing carboxyl and amino groups is used as the basic material of supramolecular hydrogel, and a suitable cross-linking agent (such as acrylamide) is selected to prepare a precursor with good mechanical strength and elasticity.

[0120] 2. Dissolution and freezing treatment: The precursor was dissolved in deionized water and then placed in a -20°C environment for freezing treatment. After 12 hours of freezing, the hydrogel became tough and had good transparency.

[0121] 3. Static treatment and morphological processing: The frozen hydrogel is placed in a nitrogen environment and allowed to stand for a while. After drying, it is cut and folded. After processing, the hydrogel is cut into the shape of a bracelet, which is suitable for wearable devices.

[0122] 4. Swelling treatment: The hydrogel in the bracelet is placed in an acidic solution containing nutrients for swelling treatment, and finally a soft, transparent hydrogel bracelet with excellent toughness and adhesion is obtained.

[0123] Application effect: The bracelet made of this supramolecular hydrogel has excellent flexibility and comfort, can be worn for a long time, has certain antibacterial properties and good biocompatibility, and is suitable for wearable health devices for monitoring physiological parameters.

[0124] Example 2: Supramolecular hydrogel for wound dressing

[0125] 1. Precursor preparation: Hyaluronic acid and chitosan are selected as the basic materials of supramolecular hydrogel, and ultraviolet light is used to initiate crosslinking to prepare a hydrogel precursor suitable for wound dressing.

[0126] 2. Dissolution and low-temperature freezing: The precursor is dissolved in deionized water to prepare a uniform gel solution, which is then frozen at low temperature (minus 30°C). During the freezing process, the internal structure of the material is enhanced, improving its toughness and tensile strength.

[0127] 3. Standing and folding: The frozen hydrogel is placed in dry air. After a period of drying, a stable layer is formed on the surface of the hydrogel. Subsequently, cutting and folding are performed to obtain a hydrogel sheet suitable for covering the wound.

[0128] 4. Swelling and functional optimization: Finally, the hydrogel sheet is placed in an acidic solution containing an antibacterial agent for swelling treatment to enhance its protective performance against wounds and have good air permeability and anti-infection effects.

[0129] Application effect: This hydrogel is used for wound dressing, which can effectively cover the wound surface, keep the wound moist, and is conducive to tissue regeneration. The transparency of the hydrogel allows doctors to easily observe the wound healing.

[0130] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0131] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a tough, transparent and adhesive supramolecular hydrogel, characterized in that: include: Step 1, preparing a supramolecular hydrogel precursor of a specific shape; Step 2, dissolving the prepared precursor in water; Step 3, freezing under low temperature conditions; Step 4, allowing the frozen supramolecular hydrogel to stand in air or dry inert gas; Step 5, cutting and folding the obtained hydrogel to process it into another shape; Step six, swelling the processed hydrogel in an acid-containing nutrient solution to obtain the final hydrogel.

2. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: In step 1, the supramolecular hydrogel polymer precursors of a specific shape include polysaccharides, polyvinyl alcohol, peptides, polyethylene glycol, and polylactic acid. The supramolecular hydrogel polymer is generated by heating under the action of the precursors and aqueous solution.

3. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: The precursor includes one or more of lipopolysaccharide, Peptides Ubiquitin, polylactic acid, PVA, PVA 1799, and PVA; and the heating temperature is 10°C-80°C.

4. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: In the method for preparing supramolecular hydrogel in step 1, the molar ratio of the precursor to the aqueous solution is 9:1, 5:1, 3:1, and 0.5:

1.

5. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: The water dissolution time in step 2 is 1 hour to 24 hours.

6. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: In step three, the operation is performed at a low temperature, and the low-temperature manufacturing tools used are tools such as a freezer or a refrigerator.

7. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: In step 4, the inert drying gas is one or more of nitrogen, helium, and argon, and is dried at room temperature.

8. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: In step 5, the operation is carried out at room temperature, and the cutting tools used are scissors or cutting machines.

9. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: The organic acid in step six comprises one or more of adipic acid, sebacic acid, suberic acid, and dodecanedioic acid.

10. The method for preparing a tough, transparent and adhesive supramolecular hydrogel according to claim 1, wherein: In the preparation method of the acid-containing nutrient solution described in step six, the molar ratio of the organic acid to the aqueous solution is 99:1, 99.9:0.1, and 99.99:0.01.

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