Phytic acid-based super- stretchable, compression-resistant, dual-physical-crosslinking conductive hydrogel, and preparation method and application thereof
By introducing hydrophobic association and hydrogen bonds into the hydrogel to form a dynamic cross-linked network, the problems of poor mechanical properties and low sensitivity of traditional hydrogels are solved, and a super-stretchable and compression-resistant conductive hydrogel is prepared for application in health monitoring and wearable devices.
Patent Information
- Application Number
- CN202411634332.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2026-01-16
- Estimated Expiration
- 2044-11-15
AI Technical Summary
Traditional hydrogels lack mechanical strength and functionality, and their cross-linked structures are easily damaged, resulting in unstable performance under external forces and low sensitivity, which limits their application in fields such as flexible sensing, electronic skin, and health monitoring.
By introducing hydrophobic association and hydrogen bonding, combined with metal coordination, and using materials such as phytic acid, hexadecyltrimethylammonium bromide, lithium chloride, and acrylamide, a dynamic cross-linking network is formed to enhance the mechanical properties and conductivity of the hydrogel, thus preparing a super-stretchable and compression-resistant double-physical cross-linked conductive hydrogel.
It achieves high resilience, excellent mechanical properties and high sensitivity. The hydrogel has good self-healing and conductivity, making it suitable for health monitoring, human-computer interaction and wearable devices.
Smart Images
Figure CN119490624B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of conductive hydrogel materials, and particularly relates to a super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid and a preparation method and application thereof. BACKGROUND
[0002] A hydrogel is a three-dimensional crosslinked network formed by hydrophilic polymer molecular chains dispersed in water through various crosslinking actions. Due to the fact that the hydrogel contains a large amount of water, the soft and wet characteristics endow the hydrogel with many excellent properties, and thus the hydrogel has a wide application prospect in many fields such as flexible sensing, electronic skin, wound dressing, health monitoring and the like. However, the traditional hydrogel lacks mechanical strength, and under the action of external force, the crosslinked structure is prone to permanent damage, and the internal structure of the hydrogel is simple and lacks special functionality, which greatly limits the application of the hydrogel.
[0003] Studies have shown that hydrophobic interaction is crucial in the life system, which can maintain the stability of the cell membrane, promote the folding of the protein chain to maintain the stability of the molecular structure, and also can enhance the toughness of the cartilage connective tissue. The hydrophobic interaction is a typical non-covalent physical interaction, and the hydrophobic association microzone formed by relying on the hydrophobic interaction as a dynamic crosslinking point can endow the hydrogel with good self-healing property and improve the mechanical strength of the hydrogel. SUMMARY
[0004] In view of the defects in the prior art, the purpose of the present application is to provide a super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid and a preparation method and application thereof. The hydrogel realizes high resilience and high sensitivity through hydrophobic interaction, hydrogen bonding and metal coordination, has potential application value in the fields of health monitoring, human-computer interaction and wearable devices, and can effectively solve the problems of low resilience efficiency, poor mechanical property and low sensitivity of the existing conductive hydrogel materials.
[0005] The first aspect of the embodiment of the present application provides a super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid and a preparation method and application thereof, which comprises the following steps:
[0006] 1) Hexadecyltrimethylammonium bromide and lithium chloride are added to water, and a uniform suspension is formed by magnetic stirring, hexadecyl methacrylate is added to the above solution, and stirring is continued until the hexadecyl methacrylate is completely dissolved to obtain a mixed solution A;
[0007] 2) Acrylamide monomer, phytic acid and initiator are added to the mixed solution A, and stirring is uniformly carried out until all are dissolved to obtain a mixed solution B.
[0008] 3) pour the mixed solution B into a mold, and perform a polymerization reaction to obtain a hydrophobically associating conductive hydrogel with high resilience and high sensitivity.
[0009] Further, in step 2), the mixed solution B is further subjected to ultrasonic treatment to remove bubbles therein.
[0010] Further, the ultrasonic treatment time is 3-5 min.
[0011] The ultrasonic treatment time is preferably 3 min, which ensures that the bubbles can be removed and the hydrogel is prevented from being gelled in the container due to the heat effect of the ultrasonic wave.
[0012] Further, the ultrasonic treatment is performed with ice water bath to prevent the solution from being gelled due to overheating.
[0013] Further, in step 3), the polymerization reaction temperature is 40-80℃, and the polymerization reaction time is 2-4 h.
[0014] Further, in step 3), the polymerization reaction temperature is 60℃, and the polymerization reaction time is 3 h.
[0015] The polymerization reaction temperature is preferably 60℃, and the polymerization reaction time is preferably 2 h, which ensures that the hydrogel can be completely gelled.
[0016] Further, in step 1), the mass ratio of cetyltrimethylammonium bromide, lithium chloride and water is (0.5-1.5):(1-3):(10-50), the magnetic stirring time is 20-40 min, and the continuous stirring time is 5-15 min; or
[0017] The magnetic stirring time is 30 min, and the continuous stirring time is 10 min.
[0018] The introduction of cetyl methacrylate can serve as a physical crosslinking point of the hydrogel, and the hydrophobic group is physically crosslinked with the acrylamide chain when the acrylamide is polymerized, so that the hydrogel has a uniform network structure. The addition of lithium chloride not only promotes the dissolution of cetyl methacrylate in the surfactant to form more hydrophobically associating micelles, but also provides free-moving ions, thereby realizing good conductivity of the hydrogel.
[0019] Further, in steps 1) and 2), the mass ratio of acrylamide to phytic acid is (0-2):(0-0.8), the mass ratio of initiator to water is (0.2-0.6):(50-150), and the stirring time is 20-40 s.
[0020] The addition of the inorganic salt can endow the hydrogel with excellent conductivity and frost resistance.
[0021] Further, in step 2), the inorganic salt is selected from sodium perchlorate or lithium chloride; and the initiator is selected from at least one of ammonium persulfate, potassium persulfate, and sodium persulfate.
[0022] The second aspect of the present application also provides a phytic acid-based super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel, which is prepared by the above method, and has a strength of 378.25 kPa, an elongation at break of 859.5%, and a strain response sensitivity value GF of 1.15.
[0023] The third aspect of the present application also provides application of the phytic acid-based super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel to health monitoring, human-computer interaction, and wearable devices.
[0024] Compared with the prior art, the present application has the following beneficial effects:
[0025] (1) The present application introduces hexadecyl methacrylate as a hydrophobic unit in the gel system, and forms dynamic hydrophobic association microzones under the action of cetyltrimethylammonium bromide, and combines with the physical crosslinking network formed by the acrylamide polymer chain, so that the synergistic effect of the two can make the gel have excellent mechanical properties and high resilience (strength of 378.25 kPa, elongation at break of 859.5%).
[0026] (2) The acrylamide molecular chain in the present application contains a large number of amino groups, which can form rich hydrogen bond interactions, and the addition of phytic acid can promote the dissolution of the acrylamide polymer chain to form more hydrogen bonds, and phytic acid itself also provides more hydrogen bond active sites, while also imparting excellent transparency to the hydrogel, and the tight crosslinking network structure in the system makes the hydrogel have fast self-repairing performance.
[0027] (3) The presence of free-moving ions in the hydrogel system of the present application makes the hydrogel have high sensitivity, and can monitor the state changes of different parts of the human body (finger, wrist, elbow, and leg bending), and the flexible touch screen made of the hydrogel can monitor different writing signals, and can distinguish the actions that generate the signals by analyzing the relative resistance change curve, and has good sensing performance.
[0028] (4) The addition of lithium chloride in the present application imparts excellent conductivity to the gel; at the same time, the preparation process provided by the present application is simple, has a short cycle, good controllability, and is easy to realize large-scale application; the prepared conductive hydrogel has high-efficiency self-repairing performance, high sensitivity, and good mechanical properties, and has a wide application prospect in the fields of health monitoring, human-computer interaction, and wearable devices. BRIEF DESCRIPTION OF DRAWINGS
[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description, and it should be understood that, after reading the content of the present application, those skilled in the art can make various modifications or changes to the present application, and these equivalent forms also fall within the scope defined by the appended claims of the present application.
[0030] Figure 1 The figure is a mechanical property detection diagram of the super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid, wherein figure a is a tensile stress-strain curve corresponding to different hexadecyl methacrylate contents, and figure b is a tensile stress-strain curve corresponding to different phytic acid contents.
[0031] Figure 2 The figure is a scanning electron microscope diagram of the super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid in the embodiment 3 of the present application.
[0032] Figure 3 The figure is a strain response sensitivity diagram of the super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid in the embodiment 3 of the present application.
[0033] Figure 4 The figure is a sensing performance detection diagram of the super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid as a flexible touch screen under different strains in the embodiment 3 of the present application, and figures a-d are relative resistance change diagrams corresponding to writing letters A, B, C and D on the hydrogel sensor.
[0034] Figure 5 The figure is a compression performance test diagram of the super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid in the embodiment 3 of the present application. DETAILED DESCRIPTION
[0035] In order to make the person skilled in the art better understand the present application, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.
[0036] Embodiment 1
[0037] A super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid and a preparation method thereof, the steps are as follows:
[0038] 1), 0.8 g of hexadecyl trimethyl ammonium bromide and 0.4 g of lithium chloride are added to 5 ml of deionized water, and a uniform solution is formed by stirring for 30 min with water bath heating, 25 mg of hexadecyl methacrylate is added to the solution, and stirring is continued for 5 min until it is uniformly dispersed, to obtain a mixed solution A; wherein the addition of lithium chloride can promote the dissolution of the hexadecyl methacrylate micelles, and form stronger hydrophobic association;
[0039] 2), 2 g of acrylamide monomer, 0.1 g of phytic acid, and 20 mg of potassium persulfate initiator are added to the mixed solution A and stirred for 30 s to dissolve them completely, and ultrasonic treatment is performed for 3 min to remove the gas bubbles in the solution, to obtain a mixed solution B;
[0040] 3), the mixed solution B is poured into a mold, and after polymerization reaction at 60°C in an oven for 2 h, it is taken out to obtain a super-stretching, compression-resistant, hydrophobically associated conductive hydrogel.
[0041] Example 2
[0042] A phytic acid-based super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel and a preparation method thereof, the steps are as follows:
[0043] 1), 0.8 g of hexadecyl trimethyl ammonium bromide and 0.4 g of lithium chloride are added to 5 ml of deionized water, and a uniform solution is formed by stirring for 30 min with water bath heating, 25 mg of hexadecyl methacrylate is added to the solution, and stirring is continued for 5 min until it is uniformly dispersed, to obtain a mixed solution A; wherein the addition of lithium chloride can promote the dissolution of the hexadecyl methacrylate micelles, and form stronger hydrophobic association.
[0044] 2), 2 g of acrylamide monomer, 0.1 g of phytic acid, and 20 mg of potassium persulfate initiator are added to the mixed solution A and stirred for 30 s to dissolve them completely, and ultrasonic treatment is performed for 3 min to remove the gas bubbles in the solution, to obtain a mixed solution B;
[0045] 3), the mixed solution B is poured into a mold, and after polymerization reaction at 60°C in an oven for 2 h, it is taken out to obtain a super-stretching, compression-resistant, hydrophobically associated conductive hydrogel.
[0046] Example 3
[0047] A phytic acid-based super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel and a preparation method thereof, the steps are as follows:
[0048] 1), 0.8 g of hexadecyl trimethyl ammonium bromide and 0.4 g of lithium chloride are added to 5 ml of deionized water, and a uniform solution is formed by heating in a water bath for 30 min, 75 mg of hexadecyl methacrylate is added to the solution, and stirring is continued for 5 min until it is uniformly dispersed to obtain a mixed solution A; wherein the addition of lithium chloride can promote the dissolution of the hexadecyl methacrylate micelles, forming a stronger hydrophobic association;
[0049] S2, 2 g of acrylamide monomer, 0.1 g of phytic acid, and 20 mg of potassium persulfate initiator are added to the mixed solution A and stirred for 30 s to dissolve them completely, and ultrasonic treatment is performed for 5 min to remove the gas bubbles in the solution to obtain a mixed solution B;
[0050] 3), pour the mixed solution B into a mold, and after polymerization reaction at 60°C in an oven for 3 h, take it out to obtain a super-stretching, compression-resistant, hydrophobically associated conductive hydrogel.
[0051] Example 4
[0052] A super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid and a preparation method thereof, the steps are as follows:
[0053] 1), 0.8 g of hexadecyl trimethyl ammonium bromide and 0.4 g of sodium chloride are added to 5 ml of deionized water, and a uniform solution is formed by heating in a water bath for 30 min, 100 mg of hexadecyl methacrylate is added to the solution, and stirring is continued for 5 min until it is uniformly dispersed to obtain a mixed solution A; wherein the addition of sodium chloride can promote the dissolution of the hexadecyl methacrylate micelles, forming a stronger hydrophobic association;
[0054] 2), 2 g of acrylamide monomer, 0.4 g of phytic acid, and 10 mg of potassium persulfate initiator are added to the mixed solution A and stirred for 30 s to dissolve them completely, and ultrasonic treatment is performed for 5 min to remove the gas bubbles in the solution to obtain a mixed solution B;
[0055] 3), pour the mixed solution B into a mold, and after polymerization reaction at 60°C in an oven for 4 h, take it out to obtain a super-stretching, compression-resistant, hydrophobically associated conductive hydrogel.
[0056] Example 5
[0057] A super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid and a preparation method thereof, the steps are as follows:
[0058] 1), 0.8 g of hexadecyl trimethyl ammonium bromide and 0.4 g of lithium chloride were added into 5 ml of deionized water, and a uniform solution was formed by heating in a water bath for 30 min, 125 mg of hexadecyl methacrylate was added into the solution, and stirring was continued for 5 min until it was uniformly dispersed, to obtain a mixed solution A; wherein, the addition of lithium chloride can promote the dissolution of the hexadecyl methacrylate micelles, and form stronger hydrophobic association;
[0059] 2), 2 g of acrylamide monomer, 0.8 g of phytic acid, and 40 mg of ammonium persulfate initiator were added into the mixed solution A and stirred for 30 s to make them all dissolve, and ultrasonic treatment was performed for 5 min to remove the gas bubbles in the solution, to obtain a mixed solution B;
[0060] 3), the mixed solution B was poured into a mold, and after being placed in an oven for polymerization reaction at 80°C for 3 h, it was taken out, to obtain a super-stretching, compression-resistant, hydrophobically associated conductive hydrogel.
[0061] Example 6
[0062] A phytic acid-based super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel and a preparation method thereof, the steps being as follows:
[0063] 1), 0.8 g of hexadecyl trimethyl ammonium bromide and 0.4 g of lithium chloride were added into 5 ml of deionized water, and a uniform solution was formed by heating in a water bath for 30 min, 75 mg of hexadecyl methacrylate was added into the solution, and stirring was continued for 5 min until it was uniformly dispersed, to obtain a mixed solution A; wherein, the addition of lithium chloride can promote the dissolution of the hexadecyl methacrylate micelles, and form stronger hydrophobic association;
[0064] 2), 2 g of acrylamide monomer, 20 mg of potassium persulfate initiator were added into the mixed solution A and stirred for 30 s to make them all dissolve, and ultrasonic treatment was performed for 5 min to remove the gas bubbles in the solution, to obtain a mixed solution B;
[0065] 3), the mixed solution B was poured into a mold, and after being placed in an oven for polymerization reaction at 80°C for 3 h, it was taken out, to obtain a super-stretching, compression-resistant, hydrophobically associated conductive hydrogel.
[0066] The performance and morphology of the hydrogels prepared in Examples 1-6 were analyzed as follows.
[0067] The phytic acid-based super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel prepared above was cut into a standard sample with a width of 5 mm and a length of 14 mm, and a universal material testing machine (Shenzhen Sanechips Co., Ltd.) was used to test the mechanical properties, and the test speed was 50 mm / min. Figure 1Fig. 1 is a mechanical property detection diagram of the super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid of the present application, wherein Fig. a is a tensile stress-strain curve corresponding to different HMA contents, and Fig. b is a tensile stress-strain curve corresponding to different phytic acid contents. As can be seen from the figures, with the increase of the HMA content and the phytic acid content, the tensile strength of the hydrogel first increases and then decreases, and the elongation at break first increases and then decreases. When the addition amount of HMA is 75 mg and the addition amount of phytic acid is 0.1 g, the hydrogel has the most excellent mechanical properties, wherein the mechanical strength is 378.25 kPa, and the elongation at break is 859.5%.
[0068] Fig. 3 shows the morphology analysis of the conductive hydrogel prepared in Example 3, which shows a good 3D porous structure. Figure 2
[0069] The super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid in Example 3 is connected with a universal testing machine, and the deformation is controlled to be different (100%-500%) with a fixed tensile rate of 50 mm / min. The relative resistance change curve caused by different deformations is recorded in real time by an electrochemical workstation. The detection results are shown in Fig. 4. Figure 3 The strain response sensitivity value of the hydrogel sensor is greater than 1, indicating that the hydrogel has very excellent conductivity and sensitivity.
[0070] The super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid in Example 3 is connected with an electrochemical workstation, and different English letters are written on the gel. The relative resistance change curve caused by different positions and different pressures is recorded in real time by the electrochemical workstation. The detection results are shown in Fig. 5. Figure 4 The hydrogel sensor shows different electrochemical signals for different letters. When the pressure is removed, the sensor can immediately restore the original resistance value, and the relative resistance change maintains good repeatability and stability.
[0071] The super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel based on phytic acid in Example 3 is designed as a cylinder with a diameter of 15 mm and a height of 10 mm, as shown in Fig. 6. Figure 5 The gel is placed on the universal testing machine, and the compression deformation is controlled to be 80%. After 10 cycles, the hydrogel can still restore to the original state, and the prepared hydrogel sensor has good compression resistance.
[0072] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions recorded in the above embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A method for the preparation of a hyper- stretch, compression resistant, dual-physical-crosslinking, conductive hydrogel based on phytic acid, characterized by, The method comprises the following steps: 1) adding cetyltrimethylammonium bromide and lithium chloride into water, forming a uniform solution by magnetic stirring, adding cetyl methacrylate into the solution, and continuing to stir until the cetyl methacrylate is uniformly dispersed to obtain a mixed solution A; 2) adding acrylamide monomer, phytic acid and initiator into the mixed solution A, stirring until all are dissolved to obtain a mixed solution B; 3) pouring the mixed solution B into a mold to perform micellar polymerization to obtain a super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel.
2. The method of making a phytic acid based, ultra-stretched, compression resistant, dual- physically crosslinked, conductive hydrogel according to claim 1, characterized in that: In step 2), the mixed solution B is further subjected to ultrasonic treatment to remove bubbles therein.
3. The method of producing a hyper-stretched, compression-resistant, dual-physically cross-linked, conductive hydrogel based on phytic acid according to claim 2, characterized in that: The ultrasonic treatment time is 3-5 min.
4. The method of making a phytic acid based, ultra-stretched, compression resistant, dual- physically crosslinked, conductive hydrogel according to claim 1, characterized in that: In step 3), the polymerization temperature is 40-80℃, and the polymerization time is 2-4 h.
5. The method of producing a phytic acid based, ultra-stretched, compression resistant, dual-physically cross-linked, conductive hydrogel according to claim 4, characterized in that: In step 3), the polymerization temperature is 60℃, and the polymerization time is 2 h.
6. The method of making a phytic acid based, ultra-stretched, compression resistant, dual- physically crosslinked, conductive hydrogel according to claim 1, characterized in that: In step 1), the mass ratio of cetyltrimethylammonium bromide, lithium chloride and water is (0.5-1.5):(1-3):(10-50), the magnetic stirring time is 20-40 min, and the continuous stirring time is 5-15 min.
7. The method of making a phytic acid based, ultra-stretched, compression resistant, dual- physically crosslinked, conductive hydrogel according to claim 1, characterized in that: In steps 1) and 2), the mass ratio of acrylamide and phytic acid is 2:(0.1-0.8), the mass ratio of initiator and water is (0.2-0.6):(50-150), and the stirring time in step 2) is 20-40 s.
8. The method of making a phytic acid based, ultra-stretched, compression resistant, dual- physically crosslinked, conductive hydrogel according to claim 1, wherein, In step 2), the initiator is at least one selected from ammonium persulfate and potassium persulfate.
9. A hyper-extended, compression-resistant, dual-physically cross-linked conductive hydrogel based on phytic acid, characterized in that: The hydrogel prepared by the method of any one of claims 1-8 has a strength of 350-500 kPa, an elongation at break of 800-1200%, and a strain response sensitivity value GF of 0.8-1.
5.
10. Application of the phytic acid-based super-stretching, compression-resistant, double-physical-crosslinking conductive hydrogel of claim 9 in health monitoring, deformation sensors and wearable devices.